Pathological diagnosis is the gold standard for cancer diagnosis. Other diagnostic tools can only achieve clinical diagnosis and cannot confirm the diagnosis. For example, imaging examinations of colonoscopy including CT or MRI, or even gastroscopy can only be considered as cancer based on imaging manifestations such as the shape of the mass and whether it is enhanced, but the final diagnosis needs biopsy and pathological clarification.
Anatomical location of rectal cancer
Both the initial confirmatory pathology report and the postoperative gross pathology will improve the definite diagnosis of cancer. However, the pathology report of biopsy provides less detailed and comprehensive information than the postoperative gross pathology. However, the pictures on the pathology report are not readable by patients. Even clinicians in general can’t understand it. In fact, it is not necessary to understand, as long as you understand the text description below the picture. The pathologist’s report is a continuous observation of the morphological and structural changes of the cells and groups under the microscope before reaching a conclusion. The pictures attached to the report may be more typical under the microscope.
I attach a real post-operative pathology report of rectal cancer below to give you an idea of the meaning of the report.
Post-operative pathological diagnosis report of rectal cancer
Pathological diagnosis: it is the conclusion of the pathological report.
Rectal cancer resection: this is the overall description of the specimen received by the pathology department, that is, what specimen I am looking at overall (the name of the specimen that the surgeon removed the lesion and organ or the endoscopist biopsied).
— Ulcerated type of medium to low differentiated adenocarcinoma, size 5*4.57 cm.
The ulcerated type is the gross staging of rectal cancer. Gross rectal subtypes: mass type, ulcerated type, and infiltrative type. Mass type: also called medullary carcinoma, cauliflower type carcinoma. It grows into the intestinal lumen and infiltrates less into the surrounding area, so it has a better prognosis. The tumor can grow very large and even block the intestinal lumen, but rarely metastasizes. Ulcerated type: it is common, accounting for more than 50%. It grows deep into the intestinal wall and infiltrates into the surrounding area, with early ulceration and easy bleeding, and this type is less differentiated and metastasizes earlier. Infiltrative type: also called hard cancer or stenosis type cancer, infiltrating along the intestinal wall, narrowing the intestinal lumen, with low differentiation, early metastasis and poor prognosis.
The differentiation degree of rectal cancer is described as the degree of malignancy, and the differentiation degree of rectal cancer is graded as follows: highly differentiated adenocarcinoma, moderately differentiated adenocarcinoma, poorly differentiated adenocarcinoma, and indolent cell carcinoma, and the degree of malignancy increases in order, which is basically the same as that of gastric cancer. Sometimes there are multiple differentiation levels mixed together
For example, high and medium differentiation, low and medium differentiation, and low differentiation with indolent cell carcinoma, and if the cancer cells secrete too much mucus, it will be classified as mucinous adenocarcinoma.
The size area of rectal cancer will be generally described.
— Invasion of plasma membrane by cancerous tissue: This is the T-stage of rectal cancer, which is the depth of tumor infiltration into the stomach wall. The rectal wall is divided into mucosal layer (T1), submucosal layer (T1), muscular layer (T2), subplasma layer (T3), and plasma layer (T4) from inside to outside. the higher the T stage, the more obvious the local progression of the tumor.
—Visible nerve invasion and no vascular cancer thrombus: vascular cancer thrombus is the presence of cancer cells within the blood vessels inside the tumor, and nerve invasion is the infiltration of cancer cells into the nerve fibers inside the tumor. These two indicators are high risk factors for recurrence of rectal cancer after surgery.
— No cancer is seen in the proximal cut margin, distal cut margin and peri-annular cut margin: it means that there is no cancer left in both sides of the severed ends and the surgery is clean. Rectal cancer cutting edge includes not only the distal and proximal ends, but also whether the peri-annular resection is clean.
Rectal cancer pattern diagram
— cancer metastasis visible in lymph nodes: it is the N stage in TNM staging. The staging is divided by the number of metastases.
N1 with 1-3 regional lymph node metastases
N1a with 1 regional lymph node metastasis
N1b with 2-3 regional lymph node metastases
N1c Tumor implantation (TD, tumor deposit) in subplasma, mesenteric, peri-peritoneal colon/rectum tissue without regional lymph node metastasis
N2 More than 4 regional lymph node metastases
N2a 4-6 regional lymph node metastases