Colon and Rectal Cancer

What Is Colon and Rectal Cancer

Colon cancer is the third most commonly diagnosed cancer in the United States, and is the second leading cause of cancer death in both men and women. The American Cancer Society estimates that close to 140,000 will be diagnosed this year with colorectal cancer, and that more than third—about 50,000—will die from it.

Colon cancer is cancer of the large intestine, or colon, which is the lower part of the digestive system. Rectal cancer is cancer of the last several inches of the colon, or rectum. Together, they’re often referred to as colorectal cancers.

Most cases of colon cancer begin as small, noncancerous, or benign, clumps of cells that are called adenomatous polyps. Some of these polyps, however, develop into cancer over time. Polyps may be small and produce few, if any, symptoms. For this reason, doctors recommend regular screening tests to help prevent colon cancer by identifying polyps before they become colon cancer.

There are several types of cancer that can start in the colon or rectum.

  • Adenocarcinomas: This is the most common type of colorectal cancer—with 95% of all colorectal cancers are adenocarcinomas—and is generally what doctors are referring to when they speak about colorectal cancer.

As well, there are other, less common types of tumors, which may also begin in the colon and rectum. Among them:

  • Carcinoid tumors: Specialized hormone-producing cells in the intestine can sometimes become cancerous tumors.
  • Gastrointestinal stromal tumors (GISTs):  Specialized cells in the wall of the colon called the interstitial cells of Cajal can become cancerous; while some are benign others are malignant. These tumors are usually found anywhere in the digestive tract, and are unusual in the colon, though they do occur.
  • Lymphomas: Cells that typically start in lymph nodes can form into lymphomas, a cancer of the immune system that can start in the colon, rectum, or other organs.
  • Sarcomas: This rare type of cancer of the colon or rectum can start in blood vessels, as well as in muscle and connective tissue in the wall of the colon and rectum.


What Causes Colon and Rectal Cancer

Risk Factors For Colon and Rectal Cancer

Diagnosing Colon and Rectal Cancer

Symptoms of Colon and Rectal Cancer


Living With Colon and Rectal Cancer



Medication And Treatment

Complementary and Alternative Treatment

Care Guide

When To Contact A Doctor

Questions For Your Doctor

Questions For A Doctor