Sometimes a biopsy, in which the doctor removes a sample of tissue to determine if there are any malignant cells, is performed. Scientists expect to develop a blood test to screen for these genes within a year, making early detection and intervention easier for those with a family history of colon cancer. An accurate blood test for the general population is further away. If any of these tests indicate a problem, other exams, such as a colonoscopy and a colon x-ray may be needed. Your internist can do a digital rectal exam and fecal occult blood test during your annual physical.
Some internists can also perform the other tests.
If your doctor can't, you'll need to go to a gastroenterologist. Unlike with other cancerous tumors, in the case of colon cancer the size of the tumor has little influence on prognosis and method of treatment. Unless the cancer is small enough to be removed by colonoscopy, surgery, or colectomy, is the primary therapy. The extent of the colon removed, and the use of additional therapy depends on the degree of the tumor's penetration into the bowel wall, the involvement of regional lymph nodes and how far the cancer has spread. In surgery the tumor and any affected surrounding tissue, including lymph nodes, are removed through an abdominal incision.