Gross morphology of colon cancer is divided into categories in the following categories:
(1) bulky: the cauliflower-like mass, broke into the intestine, the surface can be an early rupture, hemorrhage and necrosis associated with secondary infection. Most occurred in the cecum, ascending colon and rectum ampulla. This type of cancer, mostly well differentiated adenocarcinoma, not only less invasive cancer, and its transfer to the deep tissue erosion and always make happen later, so better prognosis.
(2) ulceration: the beginning of the flat-shaped mass, thereafter, was a typical crater-like ulcer, central depression, surrounded by hard and uplift, the bottom of the nodular. This type of poorly differentiated adenocarcinoma, lymph node metastasis is also earlier.
(3) stenosis: wall around this type of tumor growth and spread in the mucosa, contraction of fibrous tissue within the tumor caused by intestinal ring narrow, Guchang cause intestinal obstruction. Most of this type of cancer found in the upper part of the sigmoid colon and rectum. Poor differentiation of cancer cells through lymphatic and blood metastasis always make earlier.
(4) mucus type: this type of cancer cells can produce large amounts of mucus, it is clear cut surface of tumor-like white jelly. This will be seen up to the rectum. Can also be found in the sigmoid colon, cecum and ascending colon. Mucin-type cancer cells containing more amount of mucus, was the ring-shaped extruded nucleus. The slower growth of cancer metastasis later. But more locally aggressive, it is difficult to completely remove, easy to relapse. Poor prognosis.
Results cancer types under the microscope for the following types:
(1) adenocarcinoma: tubular or alveolar cells arranged according to the degree of differentiation can be divided into I, II, III levels. Grade III the worst differentiated cells arranged in sheets or multi-cable strips. Accounted for the majority of colon cancer.
(2) mucinous carcinoma: Most cancer cells secrete mucus, mucus cell nucleus was pushed to one side, there are interstitial mucus and fibrous tissue reaction, but the extent there are differences. Cancer in the large island shaped like mucus. Mucinous carcinoma worse prognosis than adenocarcinoma.
(3) types of undifferentiated colon cancer: small cell, round or irregular in shape, arranged in irregular flakes, infiltration, easy to small blood vessels and lymphatic invasion, the worst prognosis.