Because early detection of colon cancer and rectal cancer directly impacts outcomes,
it is important to gain an understanding of symptoms, types, stages and risk factors of these diseases.
Types of colorectal cancer
A type of cancer called adenocarcinoma accounts for more than 95 percent of colorectal cancers.
- Adenocarcinomas are tumors that start in the lining of internal organs. 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.
These are other types of cancer that can be found in the colon and rectum, but they are rare.
- Gastrointestinal stromal tumors (GIST) start in the muscle tissue of the colon. They can be benign at first, but may turn into cancer. When this happens, they are called sarcomas.
- Lymphoma is a cancer that typically starts in a lymph node, which is part of the immune system. It can also start in the colon or rectum. Lymphomas fall into two categories – Hodgkin disease and non-Hodgkin lymphoma.
- Carcinoids are tumors caused by hormones. They start in special hormone-producing cells in the intestine. Often they cause no symptoms.