digestive disorders
Colorectal Cancer
Diagnosis of Colorectal Cancer
Colonoscopy CT scan if cancer is found Genetic testing for Lynch syndrome People who have symptoms that suggest colon cancer or who have a positive Colorectal Cancer Screening need a diagnostic test to confirm whether they do or do not have cancer. People with blood in their stool require colonoscopy, as do those with abnormalities seen during a sigmoidoscopy or an imaging study. Any growths or abnormalities seen should be completely removed during the colonoscopy. X-Ray Studies of the Digestive Tract may be taken to detect tumors in the lower part of the large intestine. However, colonoscopy is the preferred diagnostic test because during colonoscopy doctors can take tissue samples to see whether a growth is cancerous or not. Once cancer is diagnosed, doctors usually do a Computed Tomography and Magnetic Resonance Imaging of the Digestive Tract of the chest, abdomen, and pelvis and do routine laboratory tests to look for cancer that has spread, to detect a low blood count (anemia), and to evaluate the person’s overall condition. Blood tests are not used to diagnose colorectal cancer, but they can help the doctor monitor the effectiveness of treatment after a tumor has been removed. For example, if levels of the cancer marker carcinoembryonic antigen (CEA) are high before surgery to remove a known cancer but are low after surgery, monitoring for another increase in the CEA level may help detect an early recurrence of the cancer. Colon cancers that were removed during surgery are now routinely tested for the gene mutations that cause Lynch syndrome. People with relatives who developed colon, ovarian, or endometrial cancer at a young age or who have multiple relatives with those cancers should be tested for Lynch syndrome. Diagnosis of MUTYH polyposis syndrome is established by genetic testing. 