Colon cancer is classified according to different parameters such as growth pattern, histological structure of the tumor, stage of disease, degree of differentiation. All of these divisions of tumors of the colon and classification are of practical importance in the selection of appropriate treatment for cancer.
By type of growth of colon cancer is divided into:
Exophytic form: while the tumor is growing in the lumen of the intestine.
Endophytic form of a tumor growing in the bowel wall thickness.
Saucer-like form: This form combines both of the above happens in the form of tumors, ulcers (hence the name).
Histological classification of colon cancer
According to the International Classification of different types of identify colon cancer:
Tumors of the colon
Muko cellular cancer.
Tumors of the colon
Histologically emit the same types of colon cancer as colorectal, as well as:
Squamous cell carcinoma.
Glandular squamous cell carcinoma.
Basal cell carcinoma.
The most common histological type of cancer is adenocarcinoma of the colon. The frequency of this type of cancer among all its other form is 80%.
Prognosis of colon cancer also depends on the degree of tumor differentiation, depth of germination in the bowel wall and adjacent organs, presence of metastasis, as regional and distant.
Classification of the extent of
According to the prevalence in our country, all malignant tumors are divided into four stages. Colon cancer is not an exception.
Stage I - Tumor affects the mucosa and submucosa.
Stage IIa - the tumor affects the bowel wall less than a semicircle, and does not go beyond it. No regional metastases.
Stage IIb - the same as in IIa, but all the affected bowel wall thickness.
Stage IIIa - Tumor affects more than half the circumference of the colon, it invades the whole wall. No regional metastases.
Stage IIIb - tumors of various sizes with multiple regional metastases.
Stage IV - extensive tumor that penetrates even in the neighboring organs, in combination with multiple regional metastases or tumor of any size with distant metastases.
More informative is now considered an international classification of tumors - so-called system is a system TNM, where each letter stands for a certain characteristic of the tumor and its extent.
T-evaluates the status of the primary tumor. Tx data to assess the primary tumor is not enough. T0 - no primary tumor is detected. Tis (carcinoma "in place"), a tumor in the thickness of the epithelium or the germination of the mucous membrane. T1 - tumor invades to the submucosa. T2 - Tumor invades the muscle layer of intestine. T3 - The tumor has struck all the layers of the intestinal wall. T4 - tumor invades serosal - outside - cover of bowel or directly spread to other organs and tissues. N - assesses the status of regional lymph nodes. N0-regional lymph nodes are not affected. N1 - Metastasis in 1-3 lymph nodes. N2 - Metastasis in 4 or more lymph nodes. M - distant metastasis are defined (in other organs). M0 - no distant metastases. M1 - have distant metastases.