Adenocarcinoma is the most common type of colon cancer but there are many other forms as well. Examples include leiomyosarcoma, lymphoma, melanoma, and neuroendocrine tumors. This article provides an overview of each colon cancer type.
Adenocarcinomas are the most common type of colon cancer and originate in glands. Adenocarcinomas account for about 90-95 percent of all colorectal cancers and have two subtypes, mucinous and signet ring cell. The mucinous subtype comprises about 10-15 percent of adenocarcinomas while the signet ring cell subtype comprises less than 0.1 percent of adenocarcinomas. (Learn more about this type of colon cancer.)
This type of colon cancer occurs in the smooth muscle of the colon. Leiomyosarcomas account for less than two percent of colorectal cancers and have a fairly high chance of metastasizing. (Learn more about this type of colon cancer.)
Colorectal lymphomas are rare and are more likely to start in the rectum than in the colon. However, lymphomas that start somewhere else in the body are more likely to spread to the colon than to the rectum. Non-Hodgkins lymphoma accounts for about 0.5 percent of all colorectal cancers and has many forms. (Learn more about this type of colon cancer.)
This type of colon cancer is rare. Usually, it results from a melanoma that started somewhere else and then spread to the colon or rectum. Melanomas account for less than two percent of colorectal cancers. (Learn more about this type of colon cancer.)
Neuroendocrine tumors are divided into two main categories: aggressive and indolent. Large cell and small cell neuroendocrine tumors are considered aggressive, while carcinoid tumors are considered indolent. (Learn more about agressive and indolent neuroendocrine tumors.)Sources:
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