Ebook Diagnostic breast imaging - Mammography, sonography, magnetic resonance imaging and interventional procedures: Part 2

161
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II Appearance


162
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9.lightThe
Normal Breast

í Anatomy

nective tissue or stromal tissue. A lobule comprises approximately 30 terminal branches (acini
or ductules) that form the parenchymal part of
the lobule. Acini and terminal ducts are surrounded by loose mesenchyma. The lobule with

The mammary gland consists of 15 to 20 lobes
with varying numbers of ducts and lobules. These
structures are surrounded by collagenous con-

Fig. 9.1 Schematic diagram and terminology of
the lactiferous duct system1

Porus excretorius
Mamilla

Areola

Pars infundibularis
Sinus lactifer

Ductus lactifer
Lobulus

Peripheral duct
Fibrous tissue
(interlobular
stroma)

ITD
Ductules
(acini)
Fibrous tissue
(intralobular stroma)

Extralobular
terminal duct
(ETD)
Intralobular
terminal duct
(ITD)
Ductules
(acini)

Terminal
ductal
lobular unit
(TDLU)

The Mature Female Breast
its light
terminal
branches, its short intralobular and
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longer extralobular duct form the terminal ductulobular unit (TDLU; Fig. 9.1). All terminal ducts
open into a lactiferous duct that runs toward the
nipple. The 15 to 20 main lactiferous ducts open
in the nipple (Fig. 9.1).
The body of the gland is imbedded in fatty
tissue. It is supplied by a network of blood and
lymph vessels and is supported in the subcu-

taneous fatty tissue by connective-tissue structures known as Cooper ligaments. These ligaments arise from the stromal tissue of the body of
the gland and insert into the prepectoral fascia
and the skin. The body of the gland, which can
vary greatly in form, size, and composition, converges toward the nipple, is generally symmetrical, and is particularly pronounced in the upper
outer quadrants.

The Adolescent Female Breast
í Histology
Histologically, the prepubescent breast consists of
lactiferous ducts with adventitial alveoli comprised primarily of connective tissue and small
amounts of fatty tissue. During puberty, the ducts
increase in length, and the terminal alveoli increase in number. These later develop into
lobules. Ductal growth triggers mesenchymal
metaplasia and formation of connective tissue.

í Clinical Examination
On palpation the breast is uniformly firm with

readily palpable glandular tissue with a total absence of any nodular or finely granular consistency.

í Mammography
The underdeveloped glandular body initially appears as a small nodule, later as a small tree-like
glandular structure. The lactiferous ducts and

connective tissue appear as a homogeneously
dense, milky structure surrounded by a narrow
layer of subcutaneous fatty tissue. Substructures
are not usually discernible with the exception of
some vessels and Cooper ligaments within the
subcutaneous tissue (Fig. 9.2).

í Sonography
The immature glandular tissue is initially relatively hypoechoic. The nodule of glandular tissue
may appear as a hypoechoic nodule and should
not be confused with a tumor. Even the developed
glandular body is still relatively hypoechoic in adolescence and cannot always be distinguished
from the surrounding hypoechoic fat. The echogenicity of the glandular tissue increases with
maturity. However, local differences in the maturity of breast tissue can occur, producing alternating areas of predominantly hypoechoic and predominantly
hyperechoic
glandular
tissue
(Fig. 9.3 a and b).

The Mature Female Breast
í Histology

í Clinical Examination

Under the influence of estrogen, progesterone,
prolactin, STH, ACTH, and corticoids, the ductal
system becomes increasingly branched. A treelike glandular structure with glandular lobules
develops. This process of growth and differentiation continues until about age 30. The highest
proportion of lobules are located far from the
nipple along the periphery, particularly in the
upper outer quadrant.

Physical examination of the normal female breast
can vary considerably. Large, fatty breasts generally have a soft consistency. In rare cases,
however, even fatty breasts will be firm and
nodular on palpation. Glandular tissue with a
high proportion of parenchymal or connective
tissue usually feels firm. Generally, there will be
less glandular tissue in the inner half of the breast
than in the outer half. Therefore the breast is
generally firmer in the upper outer quadrant due
to the increased proportion of parenchymal tissue

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164 9. The Normal Breast
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b
Fig. 9.2 a and b
Mammography is usually not indicated in asymptomatic
adolescent patients. An oblique single-view mammogram
was obtained in this 15-year-old patient because of

brownish discharge from the left nipple and because of a
sonographic indeterminate hypoechoic finding behind
the nipple
a Mammography reveals no abnormalities and shows the
typical homogeneously dense breast tissue of a 15-yearold female
b Sonography: a hypoechoic area measuring 21 mm was
noted about 1 cm behind the nipple. Considering the
brownish discharge, the symptoms might well be compatible with juvenile papillomatosis, which typically cannot
be discerned from the surrounding tissue mammographically. Further workup (puncture, cytology of the discharge) was refused by the patient

a

a

b
Parenchyma
Fat

Skin
Subcutaneous fat

Thoracic wall
and fascia

Fig. 9.3 a and b Sonography
of the adolescent breast
a The subcutaneous layer of
fat seen here is narrow as in
many adolescent breasts. The
glandular tissue is still relatively hypoechoic and thus

more difficult to differentiate
from the subcutaneous fat
than in an adult breast
b Diagram for Figure 9.3 a


The Mature Female Breast
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Fig.light
9.4 Normal
glandular tissue appears as a milky
density. Cooper ligaments appear as fine
arcs or stripes of increased density
(arrow)

in this region. If fibrocystic changes develop, the
uniformly soft to firm consistency of the breasts
may change from a finely granular to coarsely
nodular pattern on palpation.
The glandular tissue undergoes cyclical fluctuations, which may become apparent to the
woman in the second half of the menstrual cycle
as increased tissue tension or pain and enlargement of the breasts. This is due to the cyclical
swelling of the lobular tissue. Temporary enlargement of the acini also occurs. For this reason, the
glandular tissue of the breast in the second half of
the cycle and especially immediately prior to
menstruation will usually be firmer, more sensitive to pressure, and more painful.

í Mammography
Normal glandular tissue (Fig. 9.4) will appear as a
summation image of all microscopic parenchymal

and connective-tissue structures, i. e., it will produce a homogeneous mammographic appearance. This homogeneous pattern will be interspersed with islands of fatty tissue appearing as
round or curved radiolucencies in a wide variety
of individual configurations. Often increased
opacity corresponding to the physiologic distribution of parenchymal tissue will be seen in the
upper outer quadrants.
Cooper ligaments appear in the mammogram
as curved to linear densities. They extend from
the cone of breast tissue through the fatty tissue
to the skin. Depending on the specific composi-

tion of the breast, the glandular, connective, and
fatty tissues, and the ligaments can be distinguished more or less clearly. Generally, Cooper
ligaments are most prominent in the subcutaneous fatty tissue along the superior margin of
the parenchyma on the oblique or mediolateral
mammogram and in the prepectoral space.
The lactiferous duct system will not be visualized except for the large lactiferous ducts converging in the retroareolar region, where they are
visible as band-like structures.
The density of the parenchyma may vary with
the menstrual cycle. It may be denser in the premenstrual phase than in the postmenstrual
phase. This means that the mammographic appearance of the parenchyma may vary both in
terms of its structure and with respect to the
phase of the menstrual cycle.
Parenchymal structures are always more
easily discerned and their regular arrangement
converging at the nipple more easily demonstrated when fatty tissue is present. Where less
fatty tissue is interspersed, the parenchymal
structures tend to blend into a homogeneous pattern of density that can hide small pathologic lesions.
In those women with increased premenstrual
pain with resulting diminished compressibility of
the glandular tissue and the increased premenstrual density with resulting poor visualization,

mammography may be best performed in the
postmenstrual phase of the cycle.

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166 9. The Normal Breast
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í light
Sonography
(Figs. 9.5 a–i)
Glandular tissue generally appears hyperechoic,
although its sonographic appearance may vary
from moderately to highly echogenic. Surrounding or interspersed fat is hypoechoic. Rotating the
transducer will usually identify these interspersed fat lobules as oblong hypoechoic areas to
be distinguished from hypoechoic tumors. Sometimes a connection between the fat lobules and
the subcutaneous fatty tissue allows their identification. Depending on the imaging plane, hypoechoic tubular or punctate structures traversing
the glandular parenchyma will occasionally be
visible. These structures are arranged regularly in
the tissue and probably correspond to small ductal structures with periductal fibrosis or small foci
of adenosis. Such findings represent a normal variant and do not require further workup. The examiner should verify that the layer of fatty tissue
surrounding the body of the gland is completely
intact and unchanged.

Cooper ligaments are hyperechoic and permeate the layer of fatty tissue, appearing as fine
linear structures. Due to their orientation (almost
parallel to the direction of sound propagation),
Cooper ligaments can produce acoustic shadows
that occur when the sound is reflected away from
the transducer. These acoustic shadows can be

recognized by the fact that they originate from
Cooper ligaments. They can generally be eliminated by compression and do not represent a
pathologic finding.
The skin itself appears as a hyperechoic line
or, depending on the resolution of the transducer,
as a double contour whose thickness generally
does not exceed 3 mm except at the areola.
Since the retroareolar ducts run nearly parallel to the direction of sound propagation and periductal fibrosis is frequently present, the sound
waves will often be reflected away from the transducer or absorbed behind the nipple. The acoustic
shadow (“nipple shadow”) thus produced does
not represent a pathologic finding but a normal
structure that can vary. This nipple shadow may
impair visualization of the retroareolar region.

Fig. 9.5 a–i Sonography of the adult breast. Significant
individual variations can occur both in the relative proportion of hyperechoic glandular tissue and more hypoechoic
fatty tissue and in the echogenicity of the glandular tissue
itself
a Breast with dense hyperechoic glandular tissue surrounded by a narrow layer of fat. The subcutaneous fascia
is only partially visible. The prepectoral fascia is readily discernible
b Diagram for Figure 9.5 a

a

b
Subcutaneous fascia
Skin
Subcutaneous
fat
Retromammary

fat
Retromammary fat

Prepectoral fascia


167

The Mature Female Breast
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d

c

e

f
c In this breast, the hyperechoic glandular tissue (D) is
permeated with extremely regular tubular hypoechoic
structures. This image also represents a normal finding.
The hypoechoic structures probably correspond to small
ductal structures with periductal fibrosis or small foci of
adenosis. Subcutaneous and retromammary fat (F) are
visible as wide and very narrow hypoechoic strips. The
subcutaneous fascia (arrowhead) is partly visible as a fine
line of more distinct echoes
d This partially involuted breast contains abundant
hypoechoic fatty tissue in addition to a smaller amount of
remaining hyperechoic glandular tissue (D). Permeating

this fatty tissue are thin hyperechoic ligamentous structures, which can produce discrete acoustic shadows (SS)
depending on the direction of sound propagation. On the
right, a fine Cooper ligament inserting into the skin (arrows) is visible
e Extremely fatty breasts appear hypoechoic on sonography. The hypoechoic fat is transversed only by thin hyperechoic linear ligamentous structures

f–i Sometimes it may be difficult to distinguish normal
structures from pathologic changes. This may be the case
for the nipple shadow (f), for acoustic shadows posterior
to Cooper ligaments (g and h), or for interspersed fat
lobules (i)
f The dense ductal structures posterior to the nipple
often absorb sound or, if they lie parallel to the direction
of sound propagation, reflect sound energy away from the
transducer. This can produce a nipple shadow (arrow). In
contrast to the shadow posterior to a mass, the nipple
shadow begins posterior to the nipple and can vary in intensity. This shadow represents a normal structure.
Lesions in this poorly visualized area should always be
carefully excluded by careful palpation and, if necessary,
by tilting the transducer


168 9. The Normal Breast
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g

h
Fig. 9.5 g If hypoechoic fat lobules (F) are interspersed in
the glandular tissue, they may simulate a tumor (T). The
shown tumor proved to be a fibroadenoma. It is surrounded by multiple interspersed fat lobules (F). The main

criteria for differentiation include:
1. Fat lobules are easily compressible
2. In the vertical plane, the fat lobules will generally appear as long structures that often are connected to
the subcutaneous fat (see also Fig. 4.5)
h Acoustic shadows (SS) can occur at Cooper ligaments
(arrowheads) if they are parallel to the direction of sound
propagation. These shadows can be distinguished from
pathologic shadows by their point of origin. These
shadows also generally disappear when compression is increased or the transducer is tilted, i. e., they are not constant
i The same breast as in Figure 9.5 h with increased compression applied. The open arrowhead shows a Cooper
ligament that does not cause an acoustic shadow regardless of whether compression is applied. The other Cooper
ligaments produce obvious acoustic shadows without
compression, which disappear when compression is applied

i

í Magnetic Resonance Imaging
(Figs. 9.6 a–d)
MRI is not necessary for imaging the normal
breast. However, normal breast tissue will often
be incidentally visualized on MR images, or normal tissue will be diagnosed after a suspected
pathologic change has been ruled out.
In T1-weighted spoiled-gradient echo
sequences (FLASH, T1 FFE, and SP GRASS), fat has
moderate signal intensity, whereas all glandular
and ductal structures and fibrous connective
tissue (with Cooper ligaments) are visualized
with low signal intensity. After intravenous injection of the contrast medium gadolinium-DTPA,
glandular, fatty, and connective tissue do not nor-

mally enhance, i. e., these structures appear identical in precontrast and postcontrast images. Only
vascular structures can be traced through the images as small enhancing worm-like structures or
punctate cross sections of high signal intensity.
Contrast enhancement of the nipple itself occurs
in approximately 50% of all patients and should
not be regarded as pathologic in the absence of
suggestive clinical findings. Occasionally, a milky
or patchy diffuse enhancement, sometimes even
focal enhancement, can appear in normal glandular tissue. This enhancement is probably due to
hormonal changes and usually occurs in young
patients with active glandular tissue or in postmenopausal patients receiving hormone therapy
(particularly where preparations with a high pro-


The Mature Female Breast

169

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a

b

c

d
Fig. 9.6 a–d Contrast-enhanced MRI of a normal breast.
a On the T1-weighted transverse slice of the breast
(FLASH 3D), glandular and connective tissue (D) are visualized with low signal intensity, as is muscle (M). Fat (F)

shows moderate signal intensity.
b After application of contrast, normal glandular tissue
and fatty tissue only enhance slightly at the beginning of
the menstrual cycle (between the 6th and 16th days) and
in the postmenstrual phase. This means that the signal intensity hardly changes at all in comparison to the plain
image (a). Only the band of artifacts caused by blood
flowing through the heart (A) significantly increases in sig-

nal intensity, as do the vessels (arrow) that can be traced
through the images after contrast application as winding
or punctiform structures of high signal intensity
c and d In the second half of the menstrual cycle, slight to
intense diffuse or nodular enhancement patterns are
often seen in normal glandular tissue
c Comparable image of the same breast as in Figure 9.6 a
in the second half of the cycle before application of contrast
d After application of contrast in the second half of the
cycle, moderate diffuse enhancement may be seen (arrows indicate vascular structures)

gesterone content are used). It is usually transient
and more pronounced before and during menstruation. Since this enhancement can interfere
with the exclusion of malignancy and can lead to
false positive findings, we recommend to perform
contrast-enhanced MRI between day 6 to day 17

of the menstrual cycle, whenever possible. Also, it
should be performed in young patients (those
below the age of 30–35 years in whom the incidence of malignancy is typically very low and the
glandular tissue tends to be metabolically more
active) only if definitely indicated.2, 3

170 9. The Normal Breast
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Involution

í Histology

The findings of the clinical examination vary considerably, depending on the extent of the
parenchymal involution, the presence of structural changes due to benign breast disorders, and
the extent of fibrosis.

are replaced with fat as involution progresses. The
body of the gland itself becomes considerably
more radiolucent and fibrous tissue, vascular
structures, and remaining glandular lobules become more readily discernible, as do the large retroareolar ectatic lactiferous ducts (Fig. 9.7).
Involution begins in the inner half of the
breast and involves the upper outer quadrant and
the retroareolar region later. Thus mammography
in the older woman will reveal residual glandular
tissue primarily in the retroareolar region and in
the upper outer quadrant. Involution improves
the visualization of the breast. In a completely involuted fatty breast, the sensitivity of mammography approaches 100%.

í Mammography

í Sonography

The formerly dense epithelial and mesenchymal

parts of the glandular tissue that absorb radiation

The fatty involuted breast appears hypoechoic on
sonographic examination (Fig. 9.5 e). Only remaining islands of hyperechoic connective tissue and
Cooper ligaments traverse the hypoechoic fatty
tissue. Residual parenchyma generally appears as
moderately echogenic islands in hypoechoic fat.
Over 90% of breast carcinomas are hypoechoic
(similar to fatty tissue). Only some breast carcinomas have a distinctive posterior acoustic
shadow or a hyperechoic peripheral rim. This
comprises the sensitivity of ultrasonography in the
fatty breast. Islands of fatty tissue with or without
posterior shadowing due to fibrous septa can also
be mistaken for tumors. To avoid both false positive and false negative calls the sonogram should
generally be read in conjunction with mammography.
With the excellent sensitivity of mammography applied to the involuted breast, sonography is
not necessary for detecting or excluding malignancy. However, it is indicated for differentiating
cysts from solid masses since simple cysts can reliably be diagnosed even in the fatty breast.

As ovarian function decreases, involution of the
glandular body sets in. Lactiferous ducts, lobules
and parenchyma become atrophic, and fatty and
fibrous tissue dominate. Often ectasia of the large
excretory ducts occurs.

í Clinical Examination

í Magnetic Resonance Imaging

Fig. 9.7 Involution. Radiolucent glandular body only delineating Cooper ligaments, few glandular and ductal as

well as vascular structures (MLO view)

In MR images, fatty tissue has high signal intensity before and after intravenous administration
of
contrast
medium,
whereas
residual
parenchyma and connective-tissue structures
have low signal intensity. Due to the high sensitivity of mammography, contrast-enhanced MRI
is not generally needed in the fatty breast.


Asymmetry
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í light
Summary
–

The breast of an asymptomatic patient over
the age of 40 is generally examined clinically
and mammographically. In the presence of uncertain palpable and mammographic findings,
ultrasound can provide additional information. Ultrasound as the first diagnostic imaging procedure is only indicated in younger
women.
The physician should verify the clinical absence of:
–
–
–
–

–

Furthermore, imaging studies serve to verify
the absence of:
–
–
–

Palpable pathologic findings
Asymmetry
Skin or nipple retraction
Pathologic discharge

Masses and densities
Architectural distortion
Suspicious microcalcification

Comparison with the contralateral breast is
important both in light of the immense variety
in size, arrangement, and density of the
parenchyma among patients, and because
clinical, mammographic, and sonographic detection of abnormality will depend on the recognition of sometimes subtle structural abnormalities. Comparison with previous diagnostic imaging studies (where available) is
even more important.

In diagnostic imaging studies, special attention should be given to:
–
–
−

Symmetrical distribution of the body of

the gland
Regular configuration of ductal structures
converging at the nipple

Uniform skin thickness
Visualization of fine Cooper ligaments
Visualization of an undisturbed subcutaneous and retromammary layer of fat

Abnormalities
í Definition

Breasts may vary considerably with respect to
size, shape, and consistency. The following conditions are regarded as abnormalities:

–
–
–
–

Asymmetry
Macromastia
Polymastia (for example in the axillary tail or
axilla)
Inverted nipple

Asymmetry
í Clinical Examination
The most frequent abnormality is asymmetry in
breast size (anisomastia).4, 5 Depending on the
severity of this condition, which can vary greatly,

the difference in size will be more or less apparent
upon visual inspection. The difference in palpable
findings between the two breasts can vary accordingly. Patients will typically have long been aware
of the asymmetry and, apart from cyclical fluctuations, no significant changes will be observed over
time. This distinguishes anisomastia from pathologic asymmetry in size, such as can occur in the
presence of benign masses (cysts, fibroadenomas,
or phyllodes tumor) or when the consistency of one

breast gradually changes as a result of a disseminated malignant process. When this is accompanied by retraction and loss of volume—which in
fact is typical for scirrhous breast cancers—malignancy must be considered highly probable until
proven otherwise.
Asymmetry must always be assessed carefully
because it may be the presenting sign of malignancy.

í Mammography
Mammography will reveal asymmetric parenchymal distribution correlating with the clinical and
anatomic asymmetry (Figs. 9.8 a–d).

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172 9. The Normal Breast
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a

b

c

d
Fig. 9.8 a–d Glandular tissue in the axillary tail and ectopic glandular tissue (Fig. 9.8 b–d from 6)
a Glandular tissue in the axillary tail will generally have
the same structure as glandular tissue within the breast. In
the presence of regular architecture, mammography at
usual follow-up intervals will generally be sufficient (negative sonography supports this diagnosis)
b–d In the presence of irregular structure, further
workup with MRI or needle core biopsy is appropriate
b Irregularly shaped tissue is visualized in the axillary tail.

Its eccentric location did not allow its visualization in other
imaging planes. It could not be identified sonographically
c Transverse MR section through the lesion prior to administration of contrast medium
d The same slice after intravenous injection of Gd-DTPA.
In the absence of enhancement, malignancy could be excluded with a high degree of certainty. Follow-up examinations over 4 years even showed a slight decrease in density
The finding is compatible with residual asymmetric glandular or benign breast tissue


Accessory Breast Tissue (Polymastia) 173
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Macromastia
í Clinical Examination
Macromastia is a condition in which breast
volume exceeds the physiologic value by 50%, i. e.,
when the weight of the breast exceeds 600 g.
Macromastia occurs most frequently during
puberty and is rare during pregnancy. A significant increase in breast size can accompany
general obesity as increased fatty deposits are
found in the breast. The same differences in tissue

consistency are encountered as in normal
patients. However, increased breast size can render clinical examination of deeper-lying tissue
difficult or even impossible.

í Mammography
Depending on the tissue composition, the mammographic appearance will vary between radiolu-

cent in fatty breasts to radiopaque in breasts with
a high proportion of glandular and connective
tissue. Whereas mammography can achieve close
to 100% sensitivity in detecting pathologic
changes in the fatty breast, the sensitivity of
mammography in dense and voluminous tissue is
significantly reduced.

í Sonography
The diagnostic value of sonography is often
limited, particularly in very large breasts. It is difficult and often even impossible to image the entire glandular tissue. Furthermore, acoustic
shadows and limited sound penetration may not
permit sufficient visualization of the deeper-lying
tissue. For this reason, sonography in large breasts
should be used exclusively to assess focal findings.

Accessory Breast Tissue (Polymastia)
Circumscribed
development
of
glandular
parenchyma in the axilla is the most common site
of accessory breast tissue. This tissue is either

completely separate from the rest of the
parenchyma (Figs. 9.8 a–d) or connected with the
parenchymal tissue in the axillary tail. Glandular
tissue extending far into the axillary tail can occur
on one or both sides. Since breast cancer can also
occur in ectopic glandular tissue, this tissue
should always be carefully examined.
Supernumerary mammary glands are found
along the milk line (mamma accessoria) and may
or may not have an associated nipple (mamma
aberrata). Polythelia refers to the presence of supernumerary nipples without mammary tissue.

í Clinical Examination
Palpation will reveal what appears to be a soft
tumor in the axilla, which may be isolated or adjacent to the glandular tissue in the axillary tail or
at other locations. Sometimes the patient will report tenderness and fluctuations in size related to
her menstrual cycle. Swelling may also occur
during pregnancy and lactation.

í Mammography
Corresponding parenchymal densities can be
visualized mammographically with an oblique
view in the axillary tail or in the axilla on an axillary view (Figs. 9.8 a and b). The criteria for
assessment are the same as those for glandular
tissue within the breast.

í Sonography and Magnetic
Resonance Imaging
Sonography (Figs. 9.8 c and d) also visualizes the
asymmetrical configuration of normal or mastopathic glandular tissue. The same applies to MRI,

where normal tissue and benign proliferative
breast disorders normally will not enhance.
Due to its high sensitivity in detecting malignancy, MRI may be used for differential diagnostic
problems caused by asymmetric tissue.


174 9. The Normal Breast
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Inverted
Nipple
(Figs. 9.9 a–d)

í Clinical Examination
Unilateral or bilateral inverted nipples may represent normal variants. It is, however, important
that the inversion exists since birth or is longstanding (unchanged for years). Recently occurring retraction and/or inversion can be the result
of chronic inflammatory or malignant processes.
Therefore, careful history is required to determine
the need for workup of this finding.

í Mammography
Depending on the projection, the inverted nipple
can appear as a round, smooth-contoured mass
mammographically. However, in most cases, the
skin will be clearly seen to dip into this mass. The

risk of confusing this condition with a lesion is
minimal if the examiner is familiar with the clinical findings. Failure to image the nipple in profile
may result in a false mammographic picture of
nipple inversion.

í Sonography
The inverted nipple itself can appear as a hypoechoic nodule with or without an acoustic shadow.
Here, too, the risk of confusion is minimal if one
knows the clinical findings and is familiar with
the typical sonographic findings.

í Magnetic Resonance Imaging
In MR imaging studies, the examiner should bear
in mind that the normal inverted nipple can enhance.

a

d

c

e
Fig. 9.9 a–d Inverted nipple
a and b Mammographically, the inverted nipple typically
appears as a funnel-shaped density (a) or a mass (b)

c and d Sonographically, the inverted nipple can produce
a pronounced nipple shadow (e) or it may appear as a
hypoechoic nodule (d)


Pregnancy and Lactation 175
Roman
í light
Summary

Asymmetry and polymastia are congenital conditions that will generally be identified with a
careful history. The examiner must exclude significant changes that are not due to hormonal
influences (i. e., pregnancy or menstrual cycle).
If the breast examination is normal (revealing
just increased glandular tissue, but no change in
consistency, and no retraction) and mammographic appearance is normal (composition
corresponds to normal glandular tissue), then it
is highly probable that the condition represents
a normal variant.

In the presence of uncertain densities, further
diagnostic studies (mammography, ultrasound, MRI, and/or percutaneous biopsy) are
indicated (see also Chapter 22).
Congenital inverted nipple is another normal
variant which cannot be confused with a mass
if the examiner is aware of the history and
physical examination. This condition should
be distinguished from recently occurring
nipple inversion. Here, particular care should
be taken to exclude malignancy.

Pregnancy and Lactation
í Histology
During pregnancy, proliferative changes occur,
with lobular hyperplasia, hyperemia, and fluid
retention in breast tissue. Lactogenesis, the milk
synthesis in the glandular cell, begins in the second half of pregnancy. Toward the end of pregnancy, the alveoli begin to secrete and
parenchyma largely displaces the stromal tissue.

í Clinical Examination

During pregnancy, the breast increases in size and
acquires a firmer consistency, accompanied by
hyperpigmentation of the areola and nipple and
by prominent veins. The firmer consistency of the
breast makes palpation more difficult.
The proliferative stimulation can cause existing fibroadenomas to increase rapidly in size,
typically leading to smooth-contoured, mobile,
and round or oval palpable findings with a firmer
consistency than that of the surrounding glandular tissue (see p. 211). Nevertheless malignancy,
which can occur during pregnancy, needs to be
excluded with great care.
Milk retention can develop during lactation.
This can lead to focal thickening, inflammation, or
formation of a galactocele (see pp. 205−6).

í Mammography
(Fig. 9.10 a)
Mammographically, the body of the gland appears very dense with heterogeneously coarse,

a
Fig. 9.10 a–e Lactating breast
a Mammography reveals an extremely dense, heterogeneous, coarse, nodular parenchymal structure. Mammographic evaluation is impaired


176 9. The Normal Breast
b Alight
34-year-old
pregnant patient with a highly suspicious
Roman
palpable finding in the left upper inner quadrant, which

core biopsy confirmed as a carcinoma. Mammography on
the second day after delivery: The mammogram reveals a
second focal lesion with an irregular border and a highly
suspicious cluster of microcalcifications in the upper outer
quadrant. The microcalcifications are visible in greater
detail on the magnification mammogram (c)

b

c

d

e
d Prepartum heterogeneous tissue changes in the glandular body (arrowheads) during late pregnancy (normal
findings):
Whereas the peripheral glandular body appears extremely
hypoechoic like fat, the tissue posterior to the nipple is primarily hyperechoic yet interspersed with hypoechoic
tubular structures

e During lactation (different patient, normal findings),
most of the glandular tissue shows a finely granular
hypoechoic pattern. Individual expanded ducts are discernible


Breast Response with Hormone Replacement Therapy
nodular,
light confluent
Roman densities and minimal fatty
tissue. This severely limits the diagnostic value of

mammography. If clinical examination and mammography become necessary during the nursing
period, the examination should be performed
after breast feeding or pumping since the breast
then has a softer consistency and is less
radiodense. Screening mammography is usually
not performed during pregnancy or lactation. It
should be delayed for 3 to 6 months after the cessation of lactation to allow the breast density to
decrease. Diagnostic mammography may be indicated during pregnancy or lactation if clinical
suspicion exists. Although mass lesions may not
be discernible because of the increased radiodensity of the breast tissue, microcalcifications typical of malignancy can be detected even in extremely dense breasts (Figs. 9.10 b, c).
When mammography is performed during
pregnancy, the abdomen should be shielded with
lead aprons despite the fact that most of the extremely soft radiation will be absorbed in soft tissues of the abdomen and almost no radiation will
reach the fetus.

í Sonography
(Fig. 9.10 c)
In light of the limited diagnostic value of mammography during pregnancy and lactation, ultrasound is extremely helpful in evaluating palpable
findings.
Normally, the echogenicity of the breast tissue
decreases somewhat during pregnancy and lactation. The echo pattern generally appears homogeneous and finely granular. Particularly in late
pregnancy and lactation, the distended lactiferous ducts are discernible as tubular, extremely
hypoechoic or anechoic structures (Fig. 9.10 d and
e).

í Magnetic Resonance Imaging
MRI is not indicated during pregnancy and lactation since strong generalized contrast enhancement is expected in the engorged breast tissue
and therefore identification of malignant
processes would be difficult.

Breast Response with Hormone Replacement Therapy
The number of women receiving hormone replacement therapy, either for relief of menopausal symptoms or as prophylaxis against osteoporosis and cardiovascular disease* has increased
within the past few years. Due to the hormonal
proliferation stimulus, breast size increases in
some of these women, occasionally accompanied
by a sensation of fullness and breast pain.
Hormone replacement has an impact on the
mammographic image7−12:
–

–

–
–

A generalized increase in the extent and density of partially involuted parenchyma is
possible.
In older women, single or multiple cysts, fibroadenomas, and other benign breast
changes can develop in one or both breasts.
Cysts and fibroadenomas can enlarge and
simulate a malignant process.
After breast-conserving treatment of a mammary carcinoma, the extent and density of the
parenchyma of the healthy breast can increase
unilaterally since the irradiated fibrosed
breast tissue generally does not respond to
hormones.

* The value of HRT for this particular indication is debated.

The degree of increased density and appearance

of masses appears to be more pronounced for
hormone replacement therapy with estrogenprogesterone combinations than for estrogen
alone.11,12
Discontinuing hormone replacement therapy
generally leads to involution of the proliferative
parenchymal effects.
Increasing evidence exists that hormone replacement therapy thus has a negative effect on
the accuracy of mammography, at least in some
patients.13−15

í Mammography
(Figs. 9.11 a−f)
Where previous mammograms are available for
comparison, the examiner may observe a unilateral or bilateral increase in the extent and density of the parenchyma due to hormone replacement therapy. This increase can be diffuse or
patchy. Generally, the specific architecture will
still be discernible.
The increase in density can be so profound that
mammographic interpretation is impaired. Under
hormone replacement therapy, new cysts and fi-

177


178 9. The Normal Breast
light Roman

a

b
Fig. 9.11 a and b Changes under

hormone replacement therapy
a Normal, partially involuted breast
in a 59-year-old patient
b After 12 months of hormone replacement, the patient complained
of a sensation of fullness and breast
enlargement. Mammography reveals extensive generalized nodular
proliferation of glandular tissue.
Mammographic evaluation is impaired under hormone replacement
therapy compared to before
c−d In some patients new masses
may develop during hormone
replacment therapy
c Baseline mammogram before
hormone replacement therapy in a
66-year old patient
d Two years later. The patient has
been on hormone replacement
therapy for 6 months. Note that
there is a proliferation of glandular
tissue in the breast. The mass in
the upper breast was shown to be a
simple cyst on sonography

c

d


179

Breast Response with Hormone Replacement Therapy
light Roman

e

f
e−f Sometimes breast density may increase asymmetrically during hormone replacement therapy. Striking cases
such as this one require further workup.
(Diagnosis proven by vacuum biopsy and follow-up)

e Oblique mammograms before hormone replacement
therapy
f Oblique mammograms 14 months later, 7 months after
the onset of hormone replacement therapy


180 9. The Normal Breast
broadenomas
can develop or existing ones can inlight Roman
crease in size, representing an exception to the rule
that any new occurrence or increase in size of a
focal lesion in a postmenopausal patient represents a sign of malignancy. Thus, particular care is
necessary in further diagnostic workup of increasing densities. Multiple or single cysts or fibroadenomas can develop bilaterally or unilaterally.

include an increase in the amount and density
of parenchymal tissue, and a new occurrence or
an increase in the size of focal densities. Mammographic evaluation is limited instead of improved with increasing patient age and breast
involution. The additional information from
sonography may be helpful in older women undergoing hormone replacement therapy. Percutaneous or excisional biopsy may be indicated for further workup of focal findings
during hormone replacement therapy.

í Sonography
Sonography is an important diagnostic procedure
in
assessing
mammographically
dense
parenchyma and as an adjunct in diagnosing
probably benign focal findings detected mammographically, especially those that have recently
developed or increased in size. The glandular
tissue under hormone stimulation will generally
appear homogeneous and moderately hyperechoic. However, variations such as those seen in
breast dysplasia are possible.
If a simple cyst is diagnosed sonographically,
no further workup will be required. Upon consultation with the patient, solid focal lesions that are
not definitely benign mammographically and
sonographically usually require biopsy to assess
for malignancy. If they are suspected to represent
a process due to hormonal stimulation, the
patient may be given the option of discontinuing
hormones for 2 or 3 months, then reimaging the
breast to determine if the lesion has regressed.

í References
1
2

3

4

5
6

7

8

í Magnetic Resonance Imaging
MRI is not indicated for diagnosing changes occuring under hormone replacement therapy. The
resulting proliferative changes can be expected to
enhance with MR contrast agents, impairing both
detection and exclusion of malignancy.

í Percutaneous Biopsy
This method can be used to diagnose uncertain
focal findings developing during hormone placement therapy.

í Summary
Knowledge of hormone replacement therapy
is extremely important for interpreting diagnostic imaging studies. This underscores the
value of taking a thorough history.
Hormone replacement therapy can produce
significant parenchymal changes which can

9

10

11

12

13

14

15

Bässler R. Pathologie der Brustdrüse. Pathol Anat. 1978; 11
Beck R, Heywang-Köbrunner SH, Untch M et al. Contrastenhancement of proliferative dysplasia in MRI of the
breast due to the menstrual cycle. ECR ’93. Book of Abstracts. Springer International; 1993:151
Kuhl CK, Seibert C, Kneft BP et al. Focal and diffuse contrast enhancement in dynamic MR mammography of
healthy volunteers. Radiology. 1995;193(P):121
Vorherr H. The Breast. New York: Academic Press; 1974
Kopans DB, Swann CA, White G et al. Asymmetric breast
tissue. Radiology. 1989;171:639
Heywang-Köbrunner SH, Beck R. Contrast-enhanced MRI
of the breast. 2nd ed. Berlin, New York, Heidelberg:
Springer 1996
Stomper PC, Van Vorrhis BJ, Ravnikar VA et al. Mammographic changes associated with postmenopausal hormone replacement therapy: a longitudinal study. Radiology. 1990;174:487
Laya MB, Gallagher JC, Schreiman JS et al. Effect of postmenopausal hormonal replacement therapy on mammographic density and parenchymal pattern. Radiology.
1995;196:433−7
Lundstrom E. Wilczek B, von Palffy Z et al. Mammographic
breast density during hormone replacement therapy:
differences according to treatment. Am J Obstet Gynecol.
1999;181:348−52
Sterns EE, Zee B. Mammographic density changes in perimenopausal and postmenopausal women: is effect of hormone replacement therapy predictable? Breast Cancer
Res Treat. 2000;59:125−32
Greendale GA, Reboussin BA, Sie A et al. Effects of estrogen
and estrogen-progestin on mammographic parenchymal

density. Postmenopausal Estrogen/Progestin Interventions (PEPI) Investigators. Ann Intern Med. 1999;130:262−
9
Marugg RC, van der Mooren MJ, Hendriks JH et al. Mammographic changes in postmenopausal women on hormonal replacement therapy. Eur Radiol. 1997;7:749−55
Laya MB, Larson EB, Taplin SH et al. Effect of estrogen replacement therapy on the specificity and sensitivity of
screening
mammography.
J
Natl
Cancer
Inst.
1996;88:643−9
Litherland JC, Stallard S, Hole D et al. The effect of hormone replacement therapy on the sensitivity of screening
mammograms. Clin Radiol. 1999;54:285−8
Kavanagh AM, Mitchell H, Gilles GG et al. Hormone replacement therapy and accuracy of mammographic
screening. Lancet 2000;355:270−4


181
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10.
Benign Breast Disorders

í Definition

In contrast to the age-related physiologic changes
in the mammary gland, benign breast disorders
involve hormonally mediated, increased qualitative and quantitative tissue transformation prior
to and during menopause. Approximately 30% of
the time these changes involve ductal and lobular
epithelial hyperplasia. Only these are significant

for their relation to possible cancer in the future.
Breast disorders characterized by epithelial hyperplasia belong to the group of proliferative or
hyperplastic changes. Breast disorders without
epithelial hyperplasia belong to the group of nonproliferative fibrocystic changes. The distinctions
between normal findings, variations, and fibrocystic changes are blurred, as are the distinctions between individual types of this disorder.

í Pathogenesis
The causes of benign breast disorders lie in hormonal imbalances and in the interactions of
several substances (estrogens, progesterone, prolactin, thyroxin, and insulin), which trigger two
important mechanisms:
1. Hormonally induced secretion (with retention
of the secreted substance) and development
of duct ectasia and cysts
2. Endocrine-stimulated proliferation of the
ductal and lobular epithelium with development of various patterns and degrees of
epithelial hyperplasia in the form of adenosis,
epitheliosis, or atypical hyperplasia

í Incidence
Data on the frequency of benign breast disorders
vary considerably and depend on the study group.
According to statistics, the frequency of benign
disorders lies between 50% and 70% for all types
and 30% for types with epithelial proliferation.

A diagnosis of a benign breast disorder is significant for three reasons:
1. Even a benign disorder can be accompanied
by clinical symptoms (such as pain or palpable
findings) that frighten patients and can arouse
clinical suspicion of malignancy.

2. Benign disorders are generally characterized
by increased radiodensity, occasionally microcalcifications, and often nodular or firm palpable findings. Therefore mammographic visualization is limited in comparison with fatty
breasts. Locally pronounced benign changes
may mimic a focal lesion suggestive of a
malignant process.
3. Most cases of benign breast disorder (approximately 70%) do not have an increased risk of
cancer in comparison with the normal population. A portion of these cases (approximately 25%) show an increased risk of cancer
(by a factor of 1.5–2). From 3 to 5% of cases of
benign disorder are associated with an increased risk of cancer (by a factor of 4–5).

í Histopathology
Benign breast disorders involve a variety of
parenchymal and stromal changes thought to
originate in the terminal ductal lobular segment.
Small cysts containing secretion develop in the
lobules. As these increase in size, they involve the
immediately adjacent ductules (acini). The appearance of cysts, whose occurrence and growth
is further conditioned by proliferative changes in
the ducts and lobules as well as the presence of
edema and fibrotic changes in the stroma lead to
the clinical syndrome of benign breast disorder.
Benign breast disorders can involve the entire
mammary gland or may be focal. They can form a
complex with numerous histologic components,
or present as more limited entities such as
sclerosing adenosis or a radial scar. The histopathologic diagnosis of a benign breast disorder
involves the following components:


182 10. Benign Breast Disorders

í Cysts
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Roman

The breasts can form microcysts measuring
1–2 mm diameter and macrocysts (which may be
simple or multiloculated cysts), as well as multiple and solitary cysts (see Chapter 11).
í Adenosis

This term refers to parallel arrangements of
bundle-shaped nonneoplastic proliferations of
terminal ductal segments. The most frequent
forms include:

í Focal Fibrosis

Focal fibrosis is a proliferation of mammary stromal tissue in younger women (age from 25 to 40
years) that is associated with focal parenchymal
atrophy and leads to induration. The mean focus
size measures 1–3 cm in diameter. Mammography shows increased density without microcalcifications.
í Forms of Epithelial Hyperplasia

¼ Ductal hyperplasia (epitheliosis): By defini-

Blunt duct adenosis: Small cystic expansions of
ductules containing secretion, lined with a flattened or slightly hyperplastic epithelium are typical of this frequent form of adenosis. The
clustered arrangement of the ductules is suggestive of adenosis originating in the glandular
lobules as opposed to the ductal segments.
Sclerosing adenosis: Sclerosing adenosis refers to

focal, generalized, and tumor-like proliferations
(i. e., adenosis tumor) of the epithelium and myoepithelium that originate in the glandular lobules
and are accompanied by desmoplasia. Sclerosing
adenosis is frequently, but not always, associated
with other benign breast disorders. It can also
occur in the stromal tissue of fibroadenomas,
papillomas, or ductal adenomas. It can be associated with atypical lobular hyperplasia or a
lobular carcinoma in situ. The relative risk of
malignancy is increased by a factor of 1.5–2.

¼

¼

Microglandular adenosis: This rare benign form
of adenosis is characterized by densely packed,
isomorphic, small-diameter tubules that grow
into the connective and fatty tissue either resembling a tumor or occasionally as a generalized
process.
Radial scar: This term refers to single or multiple
occurrences of nonneoplastic focal tubular proliferative adenosis developing around a fibrous
elastoid center that radiate outward and are associated with areas of intraductal epithelial hyperplasia.
The radial scar is particularly significant as its
spiculated form simulates an invasive carcinoma
both macroscopically and in diagnostic imaging
studies. Areas of atypical hyperplasia, and tubular,
ductal, or lobular carcinomas can develop within
radial scars.

–

–

tion, benign intraductal proliferations of the
epithelium are seen in widespread or focal
areas whose pattern and extent can vary.
Particularly in American medical literature,
the term papillomatosis is used in the same
sense as epitheliosis. In Europe the term
papillomatosis is used to describe particular
villous epithelial structures oriented along
septa of connective tissue.
Lobular hyperplasia: It is characterized by an
enlargement of the lobule due to extensive
acinar hyperplasia in the sense of adenosis but
also due to hyperplasia of the epithelium similar to epitheliosis of the extralobular ducts.
Atypical hyperplasia (atypia): Ductal atypical
hyperplasia occurs in ducts, and lobular atypical hyperplasia in the lobules in approximately 3.6% of all biopsies. Histopathologically, these areas show some but not all of the
histologic characteristics of carcinoma in situ.
Histologic and cytologic assessment of these
lesions is difficult even for experienced
pathologists in comparative studies, and these
lesions represent a gray area in diagnosis. The
relative risk of degeneration into carcinoma is
from 4 to 5 times higher than in the normal
population and increases with age. The absolute risk with atypical hyperplasia is 8–10% in
10 years; with a history of cancer in the family,
it will increase to about 25% in 10 years. Forms
of atypical hyperplasia include:
Atypical ductal hyperplasia is primarily observed in postmenopausal patients and corresponds to a lesion with some but not all of the

characteristics of ductal carcinoma in situ.
Atypical lobular hyperplasia, likewise, has
some but not all of the characteristics of lobular carcinoma in situ. Here, the size of the
lobule (in contrast to a fully developed carcinoma in situ) is not measurably enlarged.


10. Benign Breast Disorders 183
To light
assess Roman
the risk of malignancy of benign breast
disorders, the results of long-term studies of
Prechtel1, 2 and of studies by Dupont and Page3, 4
have proven valuable. With similar goals, a consensus meeting of American pathologists5 recommended a slightly modified classification system:
Mild epithelial hyperplasia (ductal or lobular
hyperplasia) is defined as a proliferation of a
layer 2–4 cells thick. There is no increased risk
of malignancy. The disorder can occur as adenosis, cystic disease, or duct ectasia corresponding to Prechtel’s Grade I benign disorder. Frequency is about 70%. It may also
occur in fibroadenomas, adenomas, and in
mastitis.
2. Florid epithelial hyperplasia is defined as hyperplasia exceeding 4 layers of cells without
atypia. The risk of malignancy is slightly increased to 1.5–2. It occurs as solid or papillary
hyperplasia (epitheliosis), corresponding to
Prechtel’s Grade II benign disorder. Frequency
is about 25–30%, also as papilloma with a
stromal component.
3. Atypical epithelial hyperplasia (ductal and
lobular hyperplasia) is defined as cellular atypia with disturbance of regular epithelial layering, where the myoepithelial layer and basal
membrane remain intact, corresponding to
Prechtel’s Grade III benign disorder. The relative risk of malignancy is increased by a factor
of 4 or 5. Frequency is about 4%.

¼ In some cases, discharge may accompany

¼

1.

The risk of malignancy for Grade I and Grade II
disorders clearly differs from that of Grade III. In
light of this, the overriding clinical consideration
is: does the benign disorder involve atypical hyperplasia or nonatypical hyperplasia, and is there
a history of cancer in the family?

í Clinical Findings
¼ Benign breast disorders can be completely
asymptomatic.

¼ They can cause pain (mastodynia).
–

–
–

Breast pain due to a benign disorder will typically be more pronounced in the premenstrual phase (i. e., premenstrual tension or
sensitivity to touch).
The pain usually is bilateral.
Most often it will occur as generalized pain in
the upper outer quadrants. Localized pain that
is not due to a cyst is not typical of benign
breast disease (see also p. 273).

benign breast disease. This will usually occur
bilaterally and involve several excretory ducts.
The color of the discharge is usually clear or
amber-colored, occasionally yellowish green
or greenish black.
The palpable findings in the presence of a
benign breast disorder can vary greatly from
patient to patient.

Typical findings in the presence of a benign breast
disease include:
–
–
–

–

The tissue has a firmer consistency.
Palpation reveals finely to coarsely nodular
changes.
The firmer consistency and nodular transformation are most often symmetrical and particularly pronounced in the upper outer quadrants.
Cysts are usually palpable as round, elastic
lumps. Deeper-lying cysts or cysts that are not
completely filled may not be palpable.

Some benign breast disorders can also be associated with unilaterally firmer consistency or formation of focal lumps. With focal findings, it can be
difficult or even impossible to distinguish the disorder from a malignant process. Further diagnostic
workup (diagnostic imaging, percutaneous biopsy,
or perhaps excisional biopsy) is indicated.

í Diagnostic Strategy and Objectives
Benign breast disorders can only be classified histologically. Palpation, mammography (structural
changes, radiodensity, microcalcifications), or
sonography (hyperechoic glandular tissue with or
without cysts or dilated ductal structures) can be
suggestive of a benign breast disease, but cannot
prove it.
Since there is insufficient correlation among
mammographic, sonographic, or MRI findings
and cellular proliferations or the degree of cellular atypia present, it is not possible to assess the
risk of carcinoma based on diagnostic imaging studies. However, it is a general rule that the majority of benign breast disorders (70–80%) are associated with no risk or only a slight risk of carcinoma.
The increased radiodensity and firmer nodular consistency associated with typical cases of
benign breast disorders limit diagnostic accuracy
in comparison to a fatty breast. Mammographic
and clinical examination can, therefore, be more


184 10. Benign Breast Disorders
difficult
these women. Annual mammography
light inRoman
is strongly recommended to improve detection of
small carcinomas, which are more difficult to discern in dense tissue6, 7.
Additional diagnostic methods are not indicated in the presence of typical findings of benign
breast disease without an increased risk or
without mammographically or clinically suggestive findings. Where clinical examination reveals
suspicious findings (i. e., palpable findings, uncertain palpable asymmetry, or atypical discharge),
mammography is indicated as the first step in additional workup.
Mammography can detect a carcinoma at the

site of the palpable findings, or at another unexpected location, by revealing a typical density or
typical microcalcifications. The absence of microcalcifications or densities typical of malignancy in
radiodense tissue does not exclude a malignancy
suspected on the basis of clinical findings.
Therefore in the presence of clinically suggestive findings or suspected cysts in radiodense
tissue, sonography is indicated as an adjunctive
modality to mammography. Ultrasound is particularly helpful when it can identify a simple cyst as
the cause of uncertain palpable findings, uncertain
mammographic densities, or asymmetry. Aside
from this, most palpable carcinomas in radiodense
tissue are also discernible as hypoechoic mases. For
this reason, sonography is also used to confirm suspected malignant findings.
Some small carcinomas, and particularly carcinomas in situ, cannot be reliably identified by
sonography. Therefore the absence of ultrasound
findings does not exclude a malignancy suspected
on the basis of clinical or mammographic evidence.
Percutaneous biopsy is the next most important
diagnostic step and most valuable alternative to
open biopsy in the diagnosis of probably benign
palpable findings or changes detected at mammography.
Open biopsy is indicated as a diagnostic and
therapeutic method when a malignancy is suspected, and as the diagnostic method if the finding is not readily accessible (i. e., a small deep lesion), if core biopsy yielded a borderline lesion
(atypical hyperplasia), or if results of the existing
diagnostic studies or of imaging versus percutaneous biopsy are contradictory.

í Mammography
The mammographic appearance of benign breast
disease (Figs. 10.1 a–e) is characterized by the following features:

¼ Structural changes and/or increased density

in the parenchyma

¼ Calcifications

These changes can occur individually or in combination.

í Structural Changes and/or Increased Density

These changes include:
– Coarsened structure.
– Finely to coarsely nodular densities, usually
relatively uniform, often found along the treeshaped structure of the mammary gland.
– Areas of increased density or generalized increased density.
– In some cases, the structures appear indistinct
and not readily discernible. This is probably
due to increased water retention.
– Fibrosis and/or secondary inflammatory
processes can produce random and irregular
densities.
Structural changes or densities are suggestive of a
benign breast disorder, although they are not conclusive.
Benign changes are typically generalized and
symmetrical. When this is the case, the findings
are characteristic of benign breast disorders and
cannot usually be confused with changes typical
of malignancy. However, in the presence of generalized and symmetrical benign changes, detection
or exclusion of carcinomas without microcalcifications is more difficult because they may easily
be obscured by the surrounding dense tissue. Diagnostic problems occur with increased density,
architectural distortion, or even a smooth or irregular mass:
–

–

Asymmetrically, or
As a focal lesion (Figs. 10.1 f–i).

Nodular, irregular, or spiculated masses can occur
in certain benign breast diseases and characteristically also in the rare tumorous form of sclerosing adenosis.
Note:
– Irregular foci of benign breast disease and
radial scars will often produce palpable findings smaller and less pronounced than the
findings expected with a carcinoma of comparable size
– Radial scars may produce an architectural distortion with a „star-like“ pattern. The center


10. Benign Breast Disorders 185
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a

c

b

d
Fig. 10.1 a–i
a Relatively uniform, finely nodular benign breast
parenchyma of increased density
b Nodular parenchymal pattern with multiple disseminated calcifications appearing as round or linear structures
c This breast tissue shows a coarsely nodular structure in
the upper part. One coarse and some smaller calcifica-

tions are seen. The curved arrows point to calcifications
with a typical „teacup“ appearance, indicating benign microcystic changes
d This breast exhibits a coarsely nodular structure. The
nodules partially correspond to cysts, partially to well-circumscribed hyperechoic lesions (e. g., fibroadenomas) on
ultrasound