Colorectal cancer develops in the colon or rectum. Cancer that develops in the colon is called colon cancer, and cancer that starts in the rectum is called rectal cancer.

It can be of several types and depending on the cell type in the region where it starts:

Adenocarcinomas

Responsible for 95% of colorectal cancers, cancers that build upon mucus-producing cells and lubricate the inside of the colon and rectum; adenocarcinomas can be of two types: mucous tumors and serum tumors (ring-shaped tumor tumors).

Carcinoid tumors

Starts from specialized cells producing hormones in the gut; carcinoid is a slow-growing tumor type, called neuroendocrine tumor, that grows in the hormone-producing tissue, usually the digestive system.

Gastrointestinal stromal tumors

Start from specialized cells in the colon wall, called Cajal\’s interstitial cells.

Lymphomas

Cancers of the immune system cells that usually start from the lymph nodes, but also from the colon, rectum or other organs.

Sarcomas

Start from blood vessels, muscle cells or collecting tissues in the wall of the colon or rectum.