What are the types of colorectal cancer?
A type of cancer called adenocarcinoma accounts for more than 95 percent of colorectal cancers. It is the type we focus on in this section. These are other types of cancer that can be found in the colon and rectum, but they are rare. Here is an overview of the types of colorectal cancer: • adenocarcinoma Adenocarcinomas are tumors that start in the lining of internal organs. “Adeno” means gland. These tumors start in cells with glandular properties, or cells that secrete. They can form in many different organs, such as the lung or the breast. In colorectal cancer, early tumors start as small adenomatous polyps that continue to grow and can then turn into malignant tumors. • gastrointestinal stromal tumors (GIST) These are tumors that start in the muscle tissue of the colon. They can be benign (noncancerous) at first, but many do turn into cancer. When this happens, they are called sarcomas. Surgery is the usual treatment. • lymphoma A lymphoma is a cancer that typically starts in a lym
