Nghiên cứu ứng dụng siêu âm nội soi góp phần chẩn đoán giai đoạn ung thư trực tràng tt tiếng anh

1
Introduction
Rectal Cancer (RC) is a common disease in cancers. In recent
years, although progress has been made in the diagnosis, treatment,
monitoring and screening of cancer, it is still a highly fatal disease
worldwide. According to Globocan (2018), the incidence of color RC
worldwide is more than 1.8 million cases, accounting for 10.2% of
the total number of new cancer cases.
In order to designate RC surgery, which helps predict and benefit
patients, the stage assessment problem, especially to determine the
extent of tumor invasion and regional lymph node metastasis is very
important. Today with the development of science and technology,
endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) at
the sub-frenulum are very meaningful methods. Many studies show that
EUS is recognized as a good value method with accuracy ranging from
63-96%; in lymph node metastasis determination of RC is about 63-85%
compared with computed tomography (65-75%) and MRI (75-85%).
In Vietnam, the official scientific literature on the value of EUS
for diagnosing the stage of cancer is very small. Therefore, we
conduct research on the topic: "Research on application of
endoscopic ultrasound to contribute to the diagnosis of stage of
rectal cancer" with two objectives:
1. Survey of clinical characteristics, endoscopic images,
endoscopic ultrasound and histopathology of rectal cancer.
2. Evaluation of diagnostic results of endoscopic ultrasound in
determining stage of colorectal cancer.
2. The urgency of Thesis
In recent years, the issue of cancer treatment has made certain
progress. However, the effectiveness of the treatment method as well
as the treatment formula depends on the stage of cancer. Staging
assessment of the cancer is usually done by combining clinical

examination, CT, MRI, rectal ultrasound, and EUS. However,
colorectal ultrasound has the disadvantage of blind ultrasound, it is
difficult to fully assess lesions and especially the narrow evaluation
scope, it is not possible to examine rectal tumors at high points. CT
and MRI have the disadvantage of high cost, sensitivity and
specificity in diagnosis of cancer stage only about 60-70%. Many
studies published it has been shown that EUS is recognized as a good


2
value method with high accuracy, so the study of EUS in assessing
the cancer stage is very necessary.
3. New contributions of the thesis
This is the first thesis in Vietnam that applies EUS in stage
diagnosis of rectal cancer. The thesis has initially identified:
- In the diagnosis of tumor invasion from T1 to T4 level, the
general sensitivity, specificity and accuracy of endoscopic ultrasound
are 83.3%, 92.8% and 92%, respectively.
- In the diagnosis of lymph node invasion: The sensitivity,
specificity and accuracy of EUS are 73.7%; 78.6% and 77.3%
respectively.
The study also provides data on the characteristics of Rectal
Cancer on EUS: Most tumors invade the muscle layer (34.7%) and
the serosa (38.7%). 13.3% of tumors invade fat layer and organize it
around. 52% of tumors were in stage T3 and T4; 34.7% in T2; 34.7%
have lymph nodes.
4. Layout of the thesis
The thesis is presented with 112 pages including: 2-page
introduction, 31-page overview, 21-page research objects and
methods, 26-page research results, 28-page discussion, 2-page

conclusions, 1-page the limitations of the thesis, 1-page
recommendations.
The thesis has 37 tables, 6 charts, including 130 references
including 32 Vietnamese documents and 98 English documents.
CHAPTER 1
DOCUMENT OVERVIEW
1.1. Rectal anatomy
1.2. Rectal Cancer epidemiology
1.2.1. In the world
1.3. Pathogenesis pathology Rectal Cancer
1.4. Clinical manifestations
1.5. Methods of diagnosing Rectal Cancer
1.5.1. Endoscopic
Colonoscopy is still an important method for the diagnosis of
color Rectal Cancer so far. The method has the advantage of being
inexpensive, simple technique, but accurately shows the shape, size
and position of the tumor at the edge of the anus. Through endoscopy


3
combined cell aspiration with small needle to increase diagnostic
ability.
1.5.2. Intra-rectal ultrasound
Intra-rectal ultrasound (IRUS) is a procedure that uses an
ultrasound probe to be inserted into the rectum to examine rectal
ultrasound and nearby sub-pelvic organs. In general, IRUS has
similar value to CT in assessing tumors T3 and above, however when
evaluating lymph node metastasis is worse than CT. IRUS is better
than CT to assess surface tumors, while MRI provides a better image
of advanced rectal cancer. IRUS is comparable to CT in indirect

diagnosis of lymph node metastasis.
1.5.3. Computerized tomography scan
Computerized tomography (CT) allows you to identify tumors,
invasive levels, regional lymph node metastases, distal metastases,
metastases in the abdominal cavity, diagnose and identify
complications such as perforation, intestinal obstruction due to tumor.
However, CT does not assess the level of cancer invasion by the
layers of the rectum wall. With small cancers, diagnosing CT will be
very difficult. The ability to detect lymphadenopathy of CT is lower
than rectal ultrasound.
1.5.4. Magnetic Resonance Imaging scan
An MRI scan is a modern method that allows an accurate
assessment of the stage of rectal cancer, including early and recurrent
rectal cancer, from which an optimal treatment plan can be planned.
Numerous studies have shown that EUS and MRI have an additional
role in assessing the stage of the tumor.
1.5.5. PET/CT
1.5.6. CT scan of the colon lining
1.5.7. Other tests
Shooting colon frame
CEA test
Testing for hidden blood in stool (FOBT-Fecal Occult Blood Test)
1.6. Endoscopic ultrasound in diagnosis of rectal cancer
1.6.1. Endoscopy ultrasoound development history
1.6.2. Endoscopy ultrasound operating principle
Today's widely used EUS devices are designed with three types
of ultrasound probes:


4

+ Radial probes are used to diagnostic ultrasound.
+ Linear ultrasound probe is similar in structure to a Radial
probe, the ultrasound beam emanates from the end of the scope in the
shape of a fan strip and is in the same plane as the endoscope. The
transducer, in addition to the function used for diagnostic ultrasound,
also provides guidance for cell aspiration and treatment interventions.
The third type of specially designed transducer looks small like
a biopsy pliers (mini probe) is put through the biopsy channel for
ultrasound during endoscopy. This type of probe has the same
structure as the Radial transducer used for diagnostic ultrasound.
1.6.3. Rectal imaging on endoscopy ultrasound
The rectal wall image on EUS is like the different parts of the
digestive tract, which are divided into 5 layers:
The first layer of superficial mucosa, which appears as a
hyperechoic layer.
The second layer of deep mucosa, which is hypoechoic.
The third layer is hyperechoic submucosa.
The fourth layer is muscularis propria, which appears
hypoechoic.
The fifth layer is adventitial connective tissue, which is
hyperechoic.
1.6.4. Evaluation rectal cancer on endoscopy ultrasoound
Phase evaluation: According to studies of foreign authors, the
accuracy of EUS in diagnosing the level of invasion (T - according to
TNM classification) of rectal cancer ranges from 80-95%; in
identifying lymph node metastases of rectal cancer is about 70-75%.
Performing a small needle biopsy (FNA) under the EUS guidelines
increases the efficiency of diagnosing early T-stage cases and perilymph node suspected around pelvic
Lymph nodes: The accuracy of EUS in the diagnosis of lymph
nodes is lower than that of stage T because it is difficult to

distinguish between inflamed or metastatic lymph nodes as well as
identifying small or distant lymph nodes.
Evaluation of tumor stage after radiotherapy: Studies have
shown that the accuracy of EUS in assessing stage T of tumors after
radiation therapy is only 50%.


5
1.6.5. Endoscopic ultrasound to detect rectal cancer
recurrence
Several studies have shown EUS to be very accurate in detecting
recurrent cancerous tumors. The authors almost agree with the plan to
perform rectal follow-up SANS every 6 months for the first 2 years
after tumor resection surgery.
1.7. Histopathological characteristics and classification of rectal cancer
1.7.1. Histopathological classification
1.7.2. Micro injury
1.7.3. Other forms of cancer of the rectum
1.7.4. Differentiation
1.7.5. Classification of stage rectal cancer according to pathology
1.8. Research situation at home and abroad
CHAPTER 2
SUBJECTS AND METHODS OF THE STUDY
2.1. Research subjects
Includes 75 patients with rectal adenocarcinoma diagnosed by
postoperative pathology, treated at Hospital E from March 2013 to
March 2019.
2.1.1. Standard selection
- Patients with rectal tumors are detected by rectal endoscopy,
biopsy makes diagnosis of rectal carcinoma cells.

- Performing rectal tumor EUS before surgery.
- All patients underwent radical surgery at the General Surgery
Department at E. Hospital.
- Histopathology postoperative result is rectal adenocarcinoma.
- The patient agrees to participate in the study.
2.1.2. Exclusion criteria
- Patients do not meet the selection criteria.
- Patients with bleeding disorders.
- Patients with acute and chronic diseases contraindicated to
perform colonoscopy.
- Patients without surgical treatment.
- Patients who have previously treated (surgery, radiation,
chemicals).
- Patients who do not perform rectal EUS.
2.2. Research Methods


6
2.2.1. Research Methods
- Research cross-sectional description.
- Sample size: Conduct a convenient sample size.


7
2.2.2. Research facilities
- New generation EUS machine: EXERA II CV-180 light source,
EUS Radial GF-UE160 probe 3600, EU-ME1 ultrasound source from
OLYMPUS (Japan) at E Hospital Hospital's Digestive Center.
- Siemens CT device with 64 probes at Hospital Imaging Department E
- Chemicals, equipment and other means of equipment

2.2.3. Steps to proceed
2.2.3.1. Constructs an outline and data collection form
2.2.3.2. Reach patients and collect general information
2.2.3.3. Clinical research
2.2.3.4. Blood drawn for testing
2.2.3.5. Laboratory techniques
2.2.3.6. Endoscopic technique and rectal endoscopy ultrasound
* Prepare the patient
* Technical of conduct
- Rectal EUS is a special technique of ultrasound. In order for the
ray of ultrasound to reach the tissue, it is not like an ordinary
ultrasound, but the ultrasound probe is covered with a rubber ball
before being inserted into the rectum. On the endoscopic image when
the ultrasound probe is brought to the position where the ultrasound
is needed, the rubber ball is fill with water and aspirate air to create a
sound conduction environment that touches the transducer with the
tissue, parallel the water rubber ball also creates a space for the area
to be examined to focus on ultrasound to have the clearest picture.
- Inserting an ultrasound endoscope into the rectum, observing
damage with an endoscope light.
- Pump the water into the rubber ball, suck the air in the rectum
to apply the rubber ball to the wall of the rectum, slowly move the
scope in and out and look for damage on both screens: endoscopy
and ultrasound.
* Identify and evaluate results with rectal cancer
+ The image of the rectum tumor examined is the location, size,
depth of penetration, organization around the rectum and surrounding
lymph nodes.
+ Image of a normal place:
- Thickness of the wall of the rectum <3mm

- The layer structure of the rectum wall


8
- Surround the rectum by organization of fat and adjacent organs
+ Evaluation of invasive lesions on the layers of the rectum wall,
the degree of invasion of the tumor with neigh-boring organs.
+ The structure of lesions originates from the mucosa, the
density of hypoechoic is even or uneven (corresponding to the Tis
stage)
- The structure of the submucosa layer from the edge of tumor to
the central of tumor. When the tumor invades to the submucosa, it
will lose the structure of hyperechoic, instead the layer of the mucosa
thicker than usual, the structure of hypoechoic like tumor
organization (corresponding to stage T1)
- The structure of the muscle layer is evenly hypoechoic. When
the tumor invaded to the muscle layer, the thickness of the muscle
layer was higher than normal, the boundary of the muscle layer with
the submucosa was blurred and the submucosa was breakdown. The
boundary between the muscular layer and the fat around the rectum is
clear (corresponding to stage T2).
- When the tumor invades the serosa, contour structure
hyperechoic the boundary between the muscular layer and the fat
around the rectum is unevenly (corresponding to stage T3)
- The fat layer around the rectum and the structure of the organs
around rectum such as bladder, seminal vesicles, prostate gland in
men, uterus, female appendages has boundary is thin hyperechoic
strip, when see the tumor invades through the serosa layer to these
boundaries (corresponding to stage T4)
+ Evaluation of lymph nodes: lymph nodes around the rectum

on EUS have a hypoechoic structure located next to the rectum,
lymph nodes are oval or round, irregular or irregular banks, no
vascular color structure when Doppler ultrasound. Normal lymph
nodes have a uniform sound structure, regular bank, prominent navel,
normal lymph node diameter <5mm. Lymph nodes are abnormal
when the size of the lymph nodes is ≥ 5mm, the shape of lymph
nodes changes irregularly, the structure of lymph nodes hypoechoic is
unevenly, loss the structure hyperechoic of the lymph node navel
region.
2.2.3.7. CT scan sub-pelvis
Lesion assessed by CT scan:


9
- Shape of the tumor: on CT with contrast injection, the lesion
tumor catches the drug more strongly than the surrounding
organization.
- Invasive in place according to TNM classification of AJCC2010, observing the structure between the muscular layer and the
serosa, indistinguishable mucosa and submucosa.
+ T1, T2: The tumor is in the lumen, the fat layer around the
rectum is intact.
+ T3: the tumor has invaded broadly into the muscle layer, there
is not yet clear invasion of the tumor into the fat layer around the
rectum.
+ T4: there is disruption of the rectum and invasion of organs
around the rectum.
+ Evaluation of lymph nodes: lymph nodes in CT film are
suspected to be metastatic lymph nodes if the lymph nodes edge is
uneven, usually reduce density, do not absorb drugs or dissolve
heterogeneously.

2.2.3.8. Histopathological examination after surgery
The results of anatomical diagnosis are classified by the
World Health Organization, 2000 version.
2.2.4. Research targets
2.3. Data processing
The collected data was processed according to statistical algorithms
used in computerized biomedical biology with SPSS 20.0 software.
CHAPTER 3
RESEARCH RESULTS
3.1. Survey of clinical characteristics, endoscopic images, EUS
and histopathology of rectal cancer
3.1.1. Clinical characteristics
Table 3.1. Distribution by age and gender
Group of Age
< 40
40 - 49
50 - 59
60 - 69
70 - 79

No of Patient (n=75)
1
6
22
19
21

Ratio
1,3
8,0

29,3
25,3
28,0


10
≥ 80
6
8,1
Total
75
100,0
Average of Age
64,3 ± 11,1
Mainly patients aged 50-80 years old accounted for 82.6%; Average
age 64.3 ± 11.1. Male/female ratio = 1.21.
Table 3.2. Clinical of Symptoms
Symptom
Patient (n= 75) Ratio %
Bloody bowel stools
58
77,3
Abdominal pain at hypogastric region
41
54,7
Rectal examination with tumor
32
42,7
Defecation many times
24

32,0
Weight loss
22
29,3
Constipation
5
6,7
The most common clinical symptom was bloody bowel stools with
77.3%; abdominal pain at hypogastric region in 54.7% patients;
defecation many times in 32% of patients. Manual rectal examination
detected rectal tumors in 32 cases accounting for 42.7%.
3.1.2. Some subclinical tests
3.1.3. Rectoscopy images
Table 3.4. Gross Anatomy of rectal tumor
Form
Patients (n= 75)
Ratio %
Fungus
56
74.7
Ulcerative
4
5.3
Infiltrating
7
9.3
Fungus Ulcerative
8
10.7
Total

75
100.0
General images on endoscopy showed that the majority of tumors in
the fungus form accounted for 74.7% and the fungus ulcerative form
accounted for 10.7%.
Table 3.6. The level effected rectal stenosis
Level of effected
Patients (n= 75) Ratio %
Not effected stenosis
0
0
Effected stenosis ≤ ¼ perimeter
23
30.7
¼ perimeter < level of stenosis ≤ ½ perimeter
36
48.0
½ perimeter < level of stenosis ≤ ¾ perimeter
16
21.3
Total
75
100.0


11
100% of tumors cause narrowing of the rectum at different levels, of
which 78.7% of tumors cause narrowing below 1/2 the rectum.

12
3.1.4. Image characteristics of computerized tomography scans
In 75 patients, there are 52 patients accounting for 60.7%
were taken abdominal CT before surgery.
Table 3.8. Characteristics of tumor images on CT scans
Image characteristics
Patients Ratio %
Fungus on inside of rectum
36
69.2
Tumor cell
Infiltrating
16
30.8
morphology
Total
52
100.0
T1 and T2
17
32.7
T3
23
44.2
T Stage
T4
12
23.1
Total
52

100.0
N0
34
65.4
N Stage
N1
18
34.6
Total
52
100
Mostly tumors fungus on the lumen of the rectum (69.2%), in stages
T3 and T4 (67.3%) and 34.6% have surrounding lymph nodes.
3.1.5. Image of endoscopy ultrasound
10.7
17.3

72

Hypoechoic

Hyperechoic

Isoechoic

Figure 3.5. Echo characteristics of tumors on EUS
72% are tumors with Hypoechoic.


13

Table 3.9. Tumor invasive characteristics on endoscopic
ultrasound
Invasive characteristics
Patients (n= 75) Ratio %
To the layer below the mucosa
10
13.3
To muscle layer
26
34.7
To the serosa and below the
29
38.7
serosa
To fat layer and around organs
10
13.3
Total
75
100.0
Most tumors invade the muscle layer (34.7%) and the serosa
(38.7%). 13.3% of invasive tumors surrounding fat organization.
Table 3.10. Characteristics of lymph node metastasis on EUS
Characteristics of lymph node
Patients
Ratio
metastasis
%
No
49

65.3
Lymph
node
Yes
26
34.7
metastasis
Total
75
100.0
1 Node
5
19.2
2 Node
7
26.9
No of Lymph
3 Node
8
30.8
Node
4- 6 Node
6
23.1
Total
26
100.0
Size of Node
0.97 ± 0.17 (0.58 – 1.25) cm
EUS detected 26 cases, accounting for 34.7%.

Table 3.11. Classification TNM by endoscopic ultrasound
Classification TNM
Patients (n= 75)
Ratio %
T1
10
13.3
T2
26
34.7
T3
29
38.7
T
T4
10
13.3
Total
75
100.0
N0
49
65.3
N1
20
26.7
N
N2
6
8.0

Total
75
100.0


14
86.7% of tumors are located in the rectum wall; The rate of lymph
node metastasis also accounts for 34.7%.
3.1.6. Histopathological characteristics after surgery
3.1.6.1. Histopathological characteristics

Severe differentiation

Moderate differentiation

Low differentiation

Figure 3.6. Diagnosis of tumor cell differentiation by histopathology
86.7% have tumors in the degree of moderate differentiation
Table 3.12. Classification of TNM stage by histopathology
Classification TNM
Patients (n= 75)
Ratio %
T1
9
12.0
T
T2
28
37.3

T3
32
42.7
T4
6
8.0
N0
56
74.7
N
N1
18
24.0
N2
1
1.3
M0
75
100.0
M
M1
0
0.0
The percentage of tumors that invaded the serosa (T1-T3) was
92.0%; only 6 cases (8%) invaded outside the rectum wall, lymph
node metastasis rate also accounted for 25.3%; 100% have not
metastasis spread far.
Table 3.13. Diagnosis of stage of disease by histopathology
Stage of disease
Patients (n= 75)

Ratio %
Stage 1
32
42.7
Stage 2
24
32.0
Stage 3
19
25.3
Total
75
100.0


15
Patients in stage 1 account for the highest rate of 42.7%; The number
of patients with stage 2 also accounts for 32%.


16
3.1.6.2. Compare regular endoscopic images with histopathology
Table 3.14. Morphology of the tumor on the endoscope with the
degree of histopathology invasive
Histopathology
Localized
invasions
Total
p
Morphology

n
%
n
%
n
%
Fungus
52
92.9
4
7.1
56 100.0
Ulcerative
4
100.0
0
0.0
4
100.0 0.2
5
Infiltrating
7
100.0
0
0.0
7
100.0
Fungus Ulcerative
6
75.0

2
25.0
8
100.0
Total
69
92.0
6
8.0
75 100.0
100% of tumors in ulcerative and infiltrative form still localized.
Table 3.17. Compare tumor size on endoscopy with the degree of
histopathological invasion
Histopathological Localized
invasions
Total
p
Size
n
%
n
%
n
%
< 4 cm
36 92.3 3
7.7
39 100.0
4 - < 8 cm
30 96.8 1

3.2
31 100.0
0.02*
≥ 8cm
3 60.0 2
40.0
5
100.0
Total
69 92.0 6
8.0
75 100.0
* Test: χ2 test
The invasive rate to surround organization in tumor group with sized
>= 8cm is highest.
3.1.6.3. Compare CT images with histopathology
Table 3.18. Compare tumor shape on Computerized tomography
with degree of invasive on histopathology
Histopathological
Localized
invasions
Total
p
Tumor Shape
n
%
n
%
n
%

Fungus on inside of
31
86.1 5
13.9
36
100.0
rectum
0.65*
Infiltrating
15
93.8 1
6.2
16
100.0
Total
46
88.5 6
11.5
52
100.0
There is no relate between tumor shape on CT scan and degree of
invasive histopathology.


17
Table 3.19. Results of diagnosis of the degree of invasive computerized
tomography on histopathology
Histopathological
Localized
invasions

Total
p
CT scan
n
%
n
%
n
%
Localized
39
84.8
1
16.7
40
76.9
0.002*
invasions
7
15.2
5
83.3
12
23.1
Total
46 100.0
6
100.0
52
100.0

In the diagnosis of invasive rectum wall of CT: Sensitivity: 84.8%;
Specificity: 83.3%; Accuracy: 84.6%; Positive predictive value:
97.5%; Negative predictive value: 41.7%.
Table 3.20. Results of lymph node diagnosis on computerized
tomography with histopathology
Histopathological
Lymph node
lymph node
Total
p
not cancer
metastasis
CT scan
n
%
n
%
n
%
Not see lymph node
30
4
34 65.4
78.9
28.6
0.002*
See lymph node
8
21.1
10

71.4
18 34.6
Total
38
100.0
14
100.0 52 100.0
In the diagnosis of lymph node metastasis of CT scan: Sensitivity:
71.4%; Specificity: 78.9%. Accuracy: 76.9%. Positive predictive
value: 55.6%. Negative predictive value: 88.2%
3.2. Evaluate EUS's diagnostic results in definite the rectal cancer phase
3.2.1. Compare EUS images with some clinical characteristics
Table 3.22. Lymph node metastasis on EUS with clinical characteristics
No
Yes
p
Lymph node metastasis
Clinic
n
%
n
%
Abdominal pain
No
22
44.9
12
46.2
at hypogastric
Yes

27
55.1
14
53.8
0.92*
region
Total
49
100.0
26
100.0
No
9
18.4
8
30.8
Bloody bowel
Yes
40
81.6
18
69.2
0.22*
stools
Total
49
100.0
26
100.0
No

35
71.4
16
61.5
Defecation many
Yes
14
28.6
10
38.5
0.38*
times
Total
49
100.0
26
100.0


18
No
49
100.0
21
80.8
Yes
0
0.0
5
19.2

0.001**
Total
49
100.0
26
100.0
No
36
73.5
17
65.4
Weight loss
Yes
13
26.5
9
34.6
0.46*
Total
49
100.0
26
100.0
No
27
55.1
16
61.5
Rectal
examination with

Yes
22
44.9
10
38.5
0.59*
tumor
Total
49
100.0
26
100.0
Patients with constipation have higher rate of invasive lymph nodes
(p = 0.001).
3.2.2. Compare endoscopic ultrasound images with blood tests
3.2.3. Compare EUS images with regular endoscopy images
Table 3.25. The degree of tumor invasion on endoscopic ultrasound
with normal endoscopic images
Localized
invasions
EUS Image
P
(n=65)
(n=10)
Endoscopic images
n
%
n
%
1/3 Low

20
30.8
3
30.0
Location of
1/3 Mid
23
35.4
4
40.0
0.96*
tumor
1/3 Up
22
33.8
3
30.0
Fungus
49
75.4
7
70.0
Ulcerative
4
6.2
0
0.0
Shape
0.12*
Infiltrating

7
10.8
0
0.0
Fungus Ulcerative
5
7.7
3
30.0
< 4cm
37
56.9
2
20.0
Largest
4 – 8cm
26
40.0
5
50.0
0.003*
diameter
≥ 8cm
2
3.1
3
30.0
¼ perimeter
20
30.8

3
30.0
The degree
of stenosis
½ perimeter
35
53.8
1
10.0
0.003*
¾ perimeter
10
15.4
6
60.0
The rate of invasion of surround organization on EUS gradually
increases with the degree of tumor narrowing on normal endoscopy
(p = 0.003).
Constipation


19
Table 3.26. The degree of invasive lymph node on endoscopic
ultrasound with normal endoscopic images
No (n=49)
Yes (n=26)
EUS Image
Endoscopic images
n
%

n
%

p

1/3 Low
16
32.7
7
26.9
1/3 Mid
17
34.6
10
38.5 0.87*
1/3 Up
16
32.7
9
34.6
Fungus
35
71.4
21
80.8
Ulcerative
4
8.2
0
5.3

Shape
0.03*
Infiltrating
7
14.3
0
0.0
Fungus Ulcerative
3
6.1
5
19.2
< 4cm
28
57.1
11
42.3
Largest
4 – 8cm
20
40.8
11
42.3 0.07*
diameter
≥ 8cm
1
2.1
4
15.4
¼ perimeter

14
28.6
9
34.6
The degree
of stenosis
½ perimeter
28
57.1
8
30.8 0.05*
¾ perimeter
7
14.3
9
34.6
The rate of lymph node detection in EUS is common in tumors that
have fungus or fungus ulcerative (p = 0.03).
3.2.4. Compare endoscopic ultrasound images with CT images
Table 3.27. The results of diagnosis of invasive degree by endoscopic
ultrasound with computerized tomography
EUS
Localized
invasions
p
Kappa
CT
Coefficient
n
%

n
%
Localized
37
86.0
3
33.3
0.003*
0.47
invasions
6
14.0
6
66.7
Total
43
100.0
9
100.0
In the diagnosis of the degree of wall invasion of tumor between EUS
and CT, there is a fairly rather compatible between the two methods
with a suitable coefficient Kappa = 0.47 and p = 0.003.
Location of
Tumor


20
Table 3.28. Diagnostic results of the degree of invasive lymph
node by endoscopic ultrasound with computerized tomography
EUS

No
Yes
p
Kappa
CT
Coefficient
n
%
n
%
No
28
84.8
6
31.6
< 0.001*
0.54
Yes
5
15.2
13
68.4
Total
33
100.0
19
100,.0
The rather level of compatible between the two methods and Kappa
coefficient = 0.54 and p <0.001.
3.2.5. Compare EUS images with histopathological results

Table 3.29. The degree of invasion on EUS with histopathology
Localized
invasions
p
EUS
Histopathology
n
%
n
%
Hight Differentiation
5
7.7
2
20.0
58
89.2
7
70.0
Differen Mid Differentiation
0.25*
tiation
Low Differentiation
2
3.1
1
10.0
Total
65
100.0 10

100.0
1 Stage
30
46.2
2
20.0
2
Stage
22
33.8
2
20.0
Stage of
0.03*
disease 3 Stage
13
20.0
6
60.0
Total
65
100.0 10
100.0
Tumors in stage 3 has trend to invade surround organization on EUS
is much more than stage 1 and 2 (p = 0.03).
Table 3.31. Stage T diagnostic results by EUS with histopathology
Stage T
Histopathology
Threshold
Over

Under
p
EUS
n T1 T2 T3 T4 threshol threshol
d
d
T1
10 8
2
0
0
0%
20%
T2
26 1 22 3
0
3.8%
11.5%
<0.001*
T3
29 0
2 26 1
6.9%
3.4%
T4
10 0
2
3
5
50%

0%
In diagnosing the extent of tumor invasion, EUS tends to diagnose
over threshold for tumors from T2 and above (p <0.001).


21
Table 3.32. The result of diagnosis degree of invasive by EUS
Histopathology
Localized
invasions
Total
p
EUS
n
%
n
%
n
%
Localized
64
92.8
1
16.7
65
86.7
invasions
5
7.2
5

83.3
10
13.3
<0.001*
Total
69
100.0
6
100.0
75
100.0
The sensitivity, specificity and accuracy of EUS in diagnosing tumor
invasion are 83.3%, 92.8% and 92%, respectively.
Positive predictive value: 98.5%, Negative predictive value: 50%.
Table 3.33. Results of diagnosis of stage T1 by EUS with
histopathology
Histopathology
Not T1
T1
Total
p
EUS
n
%
n
%
n
%
Not T1
64

97.0
1
11.1
65
86.7
T1
2
3.0
8
88.9
10
13.3
<0.001*
Total
66
100.0
9
100.0 75 100.0
The sensitivity, specificity and accuracy of EUS in the T1 stage
diagnosis of tumors were 88.9%, 97% and 96%, respectively.
Table 3.34. Results of diagnosis of stage T2 by EUS with
histopathology
Histopathology
Not T2
T2
Total
p
EUS
n
%

n
%
n
%
Not T2
43
91.5
6
21.4
49
65.3
T2
4
8.5
22
78.6
26
34.7
0.03*
Total
47
100.0
28
100.0
75
100.0
*: Test: Fisher’s 2-side.
The sensitivity, specificity and accuracy of EUS in the diagnosis of T2
stage of tumors were 78.6%, 91.5% and 86.7%, respectively.
Table 3.35. Results of diagnosis of stage T3 by EUS with

histopathology
Histopathology
Not T3
T3
Total
p
EUS
n
%
n
%
n
%
Not T3
40
93.0
6
18.8
46
61.3
T3
3
7.0
26
81.2
29
38.7
<0,001*
Total
43

100.0
32 100.0 75
100.0
The sensitivity, specificity and accuracy of EUS in the diagnosis of


22
T3 stage were 81.2%, 93.0% and 88%, respectively.


23
Table 3.36. Results of T4 stage diagnosis by EUS with histopathology
Histopathology
Not T4
T4
Total
p
EUS
n
%
n
%
n
%
Not T4
64
92.8
1
16.7
65

86.7
T4
5
7.2
5
83.3
10
13.3
<0.001*
Total
69
100.0
6
100.0
75
100.0
The sensitivity, specificity and accuracy of EUS in the diagnosis of
T4 stage were 83.3%, 92.8% and 92%, respectively.
Table 3.37. Results of diagnosis of lymph nodes on EUS
Histopathology
Lymph nodes
lymph node
Total
p
not cancer
metastasis
EUS
n
%
n

%
n
%
Not lymph node
44
78.6
5
26.3
49
65.3
0.002*
Lymph node
12
21.4
14
73.7
26
34.7
Total
56
100.0
19
100.0
75 100.0
The sensitivity, specificity and accuracy of EUS in the diagnosis of
lymph nodes are 73.7%; 78.6% and 77.3% respectively. Positive
predictive value: 53.8%. Negative predictive value: 89.8%.
CHAPTER 4
DISCUSSION
4.1. Dissect clinical features, endoscopic images, endoscopic

ultrasound and histopathology of rectal
4.1.1. Age and gender characteristics
4.1.2. Clinical symptoms
A lot of patients in our study group had symptoms of bloody bowel
movements, accounting for 77.3%. Besides, we also encountered
some other symptoms such as lower abdominal pain in 54.7%;
defecation many times in 32% of patients; weight loss was 29.3%
and constipation was only as low as 6.7%. In 75 patients, manual
rectal examination detected rectal tumors in 32 cases accounting for
42.7%. In general, the clinical symptoms of rectal cancer are diverse,
easily confused with the manifestations of other pathologies in the
colon, but are common signs: bloody bowel movements, repeated
bowel movements, stool shape changes.
4.1.3. Subclinical characteristics


24
4.1.4. Endoscopic images
Locations of the tumor on the colonoscopy
Determining the location of a rectal tumor, or more precisely,
the distance of the tumor vs the edge of the anus is essential. With
surgeons to offer suitable surgical methods. Research results of
patients show that the tumor in the middle 1/3 of the rectum accounts
for 36%, 1/3 above (33.3%) and 1/3 below 30.7%.
General image of the tumor
In our study, general images on endoscopy showed that the
majority of tumors in the fungus form accounted for 74.7% and the
fungus haematodes form accounted for 10.7%; ulcerative form of
5.3% and infiltrating form 9.3%. Of which, it is worth noting that the
infiltrates form are easy to miss when colorectal endoscopy

(especially when the colon is not clean and the damage has not
progressed to a level that causes narrowing of the colon and
withdrawal machine too fast). Few cases of this type of infiltration
have been missed at the first colorectal colonoscopy, but thanks to
suspected clinical symptoms, and combine images on the EUS is
quite clear and should be performed colorectal colonoscopy 2nd with
biopsy for more accurate diagnosis lesions.
The size of the tumor
In our study, the largest tumor size <4 cm accounted for
52%; followed by tumors with the size of 4 - <8 cm accounting for
41.3% .100% of tumors cause rectal stenosis at different levels, of
which 78.7% of tumors cause stenosis under 1/2 rectum colon.
4.1.5. Computerized tomography images
In our study, 52 patients had pre-surgery CT scans. The study
results showed that on CT scans, the tumors were mostly in the
rectum (69.2%), in T3 and T4 (67.3%) and 34.6% had surrounding
lymph nodes.
4.1.6. Histopathological characteristics
Degree of differentiation
All patients in this study had histopathological results as
rectal adenocarcinoma. In our study, the histopathological results
showed that the majority of patients had tumors with moderate
differentiation (86.7%), mild differentiation accounted for 4.0% and
severe differentiation was only 9.3%.


25
The degree of tumor invasion compared to the intestinal wall
In our study, the majority of tumors invaded the muscular layer
and the serosa (T2 and T3) accounting for 80%, lymph node

metastasis rate also accounts for 25.3%, There were no cases of
distant metastasis.
Stase division by TNM
In our study the majority of patients in stage I accounted for 42.7%,
the number of patients in stage II accounts for 32%, 25.3% of
patients in stage III. There are no cases in stage IV. Many studies by
foreign authors have found that patients diagnosed early in stages I
and II have a much better prognosis than patients in stages III and IV.
4.1.7. Endoscopic ultrasound image
Echogenic density of the tumor
In our study, the tumor was primarily a hypoechoic (72%).
On EUS the tumor usually appears as a hypoechoic mass. This is a
common sound structure found in neoplasia tumor. The sound density
can also be hyperechoic or mix (that is, there is hyperechoic area
interlaced mixed hypoechoic). A decrease in negative density is an
indication of abnormal neoplasia tissue, blood-rich tissue. However,
if there are many interlaced fibrous organizations in there, making
the structure of tumor tissue will be more hyperechoic.
The extent of tumor invasion
Assessing the extent of tumor invasion by EUS is based on
the degree of tumor invasion compared to the wall of the rectum.
Based on this structure, when conducting EUS for 75 cases of rectal
tumor we found that only 10 patients accounted for 13.3% of the
invasive tumor coming to the submucosal layer; The majority of
tumors invaded the muscular layer and the serosa (34.7% and 38.7%,
respectively). 13.3% of tumors invaded fat and organized around.
Thus, there are no cases where the tumor is localized in the mucous
membrane and mucosa, which means that no patient has been
indicated for mucosal resection through endoscopic and that all have
indications for radically surgery treatment. When dividing the tumor

invasion by TNM stage on EUS, we found that most of the tumors
had invaded to muscle layer of 34.7% (stage T2), to serosa layer and
over serosa layer is 38.7%, only 13.3% tumors in stage T4 and 13.3%