Colorectal cancer symptoms may be minor or non-existent during the early stages of the disease, although there may be some early warning signs. The symptoms of colorectal cancer may not develop until the disease has progressed into stage II or beyond. Regular screening tests for cancer of the colon or rectum, especially with a colonoscopy, is recommended as part of a health plan for those over 50 years old or those under 50 who are at high risk or have a family history of the disease or other cancers. Talk with your doctor about when you should start regular colorectal cancer screening.
Several tests may be used to diagnose colorectal cancer. These tests may include a colonoscopy, or other endoscopic procedures, stool tests, or other lab tests, or an MRI, CT scan or PET/CT scan. In many cases, a biopsy may be required. These imaging and laboratory tests may also be used to track the size of tumors and monitor response to treatment.
Rectal cancer often does not have symptoms in the early stages. When it does have symptoms, they vary from person to person. Most rectal cancers begin as polyps, small non-cancerous growths on the rectum wall that can grow larger and become cancer.
Many people with colon cancer experience no symptoms in the early stages of the disease. When symptoms appear, they'll likely vary, depending on the cancer's size and location in your large intestine.
Make an appointment with your doctor if you have symptoms suggesting rectal cancer, particularly blood in your stool or unexplained weight loss.