Professor MD Wolfgang Hoffmann
Large intestine, or large bowel, is a lower part of gastrointestinal tract including cecum, colon, rectum and anal canal. Sometimes there is confusion here as many sources refer to the colon as “large intestine” that can be taken in certain limits but is not completely correct. Though the colon is a main part of the large intestine but not the same as it is.
As it was mention above, large intestine consist of the following sections:
The most of cancerous tumors of the large intestine are developed in the colon and rectum. There is a term used for the cancer in those sections which is “colorectal cancer”.
Colorectal cancer is the third most common cause of the cancer deaths (in women even second one) after lung cancer and liver cancer. It often starts from non-cancerous neoplasm called polyps that after can turn into malignant tumor. The majority of colorectal cancers are adenocarcinomas. Among the rarer types of cancer in the colon and rectum are lymphomas, stromal tumors of the large intestines, carcinoids, leiomyosarcomas and melanomas.
The sigmoid colon and rectum are the sites where colorectal cancer occurs especially often. For more information on colon cancer please check main article "Colon Cancer".
Cecum cancer happens rarer than cancers in the other sections of the large intestine. It counts only 15-20% of all the cases. It is quite difficult to detect and may develops for years asymptomatically. Most of malignant lesions in the cecum are carcinoid tumor. Sometimes, appendiceal carcinoid tumors can be found in the appendix adjacent to the cecum.
Most anal cancers develop from the cells of mucosa but adenomarcinonas also can occur. Anal cancer is quite rare.
In early stages large intestine cancer causes fewer symptoms. You may notice appearing the signs as:
If you have rectal cancer you may feel that your bowel has not been completely evacuated after defecation. Also, the feeling of fullness of the rectum can be present.
Unlike colorectal tumors, cancer in cecum may not cause any discomfort of bowel habits changes and that is the reason why most of cecum cancers are diagnosed in advanced stage.
On advances stages of large intestine cancer you may feel general weakness, get tied quickly and have symptoms of nausea and vomiting. The last symptoms may be the signs of obstruction, or blockage in the bowel. This is a clinical condition which requires immediate hospitalization. Anemia and weight loss are also can be the signs of advanced cancer.
In early stage surgery is an effective way of large intestine cancer. For early detection of bowel cancer is recommended routing screening if you are older than 50.
Colonoscopy is a common procedure for diagnostics and surgery of the large intestine cancer. The bowels are screened with colonoscope, a special optical tube, which is introduced into intestine through the anus. During colonoscopy a surgeon can view the situation inside the large intestine and remove any neoplasm found. The procedure of polyps removing is known as polypectomy.
After the procedure the samples of removed tissues are sent for cytological analyses. If any malignancy is found you may need associated treatments as chemotherapy or radiotherapy. Every cancer is individual, so only after studying your personal situation it can be decided if you need further treatment.
In later stages you may need other kind of large intestine surgery as below: