Cancer Treatment Centers of America

Biopsy for colorectal cancer

Biopsy for colorectal cancer

Biopsies may be critical in helping diagnose colorectal cancer. A gastroenterologist performs a biopsy by retrieving polyps and other tissue samples from the colon or rectum during a colonoscopy. Tissue samples may also be retrieved during other endoscopic procedures, such as a sigmoidoscopy or endoscopic ultrasound. The polyps and samples are then sent to a laboratory to be analyzed under a microscope to check for cancer cells.

What is a biopsy?

During a biopsy, a doctor removes a sample of tissue or fluid from the body. A pathologist inspects the cells under a microscope to see if they are cancerous. 

Some biopsies are performed under image guidance, such as ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI). This allows your doctor to collect cells from deeper inside the body. Depending on the type of biopsy performed, you will receive an anesthetic to reduce discomfort.

Compared with other diagnostic tests for cancer, biopsies often provide a more definitive diagnosis. A biopsy may help determine whether the cancer began at the site of the biopsy sample, or if it started somewhere else in the body and spread to the site of the biopsy sample.

Some sites that are commonly biopsied include the breast, skin, bone marrow, GI tract, lung, liver, bladder, colon and lymph nodes. Our doctors determine the most appropriate method of biopsy based on several factors, such as the size, shape, location, and characteristics of the abnormality.

Biopsy medical animation