Rectal cancer belongs to tumors the diagnostics of which requires just a routine examination. Unlike other colon tumors, it is sensitive to irradiation and chemotherapy, but the best result is achieved only when these are combined with surgery. As a rule, the tumor occurs in the middle part of the gut called ampulla.
Rectal cancer causes
The main risk factor are polyps, yet not all, but those having a villous structure. In addition, the probability of a polyp malignization is related to its size and duration of existence, the larger the size, the higher the likelihood of cancer, so all polyps must be removed.
Adenocarcinoma more often develops in the peoples of East Asia, and it is assumed that there is a close relationship with their nutrition and genetics. For some reason, the condition is more common in men, but heredity has no significant role.
Rectal cancer diagnostics
Rectal cancer is recognized as a condition that can be detected very early, by visual localization of a malignant tumor. Detection of rectal pathology does not require complex equipment, the surgeon just needs to feel the intestine with a finger from the inside. Digital examination is included in the standard surgical technique, but it is performed very rarely, therefore, the condition is infrequently detected at an early stage.
This cancer manifests itself in unpleasant symptoms, usually a change in defecation character, pain and bleeding, but at the beginning of the malignant neoplasm development there are no clinical signs.
Rectal cancer stages
Previously, the stage of cancer was determined by the tumor size, but it turned out that much more important for the prognosis, and hence for the choice of optimal treatment, are the depth of cancer cells penetration into the intestine wall and existence of metastases in nearby lymph nodes. If the tumor has not yet involved the lymph nodes in the process, then this is early cancer stage I and II.
- At stage I, the tumor is limited to the rectal mucosa.
- Its growth through the entire intestinal wall, but without going beyond the organ limits, takes the process to stage II.
- Metastases in the lymph nodes near the intestine at any size of the primary tumor change the stage to III.
- Stage IV is diagnosed only with metastases in other organs, most often in the liver and lungs.
A very important prognostic sign is the degree of neoplasm malignancy determined by maturity of the cells. The more primitive a cell is, the more aggressive it multiplies. The cancer of the most primitive cells is called undifferentiated, and it quickly metastasizes. The neoplasm with a high differentiation has the lowest malignancy and the best prognosis. Accordingly, a moderately differentiated cancer has an average degree of aggressiveness.