The American Gastroenterological Association is a non-profit organization with more than 14,500 physician and scientist members who research, diagnose and treat disorders of the gastrointestinal tract and liver.

The American Society of Colon and Rectal Surgeons is a national association of colon and rectal surgeons focused on the treatment of diseases and disorders affecting the colon, rectum and anus.

A non-profit education and research organization that assists and supports people affected by gastrointestinal (GI) disorders.

A resource for information on diseases of the colon and treatment options for patients with colon cancer.

The National Digestive Diseases Information Clearinghouse (NDDIC) is an information dissemination service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). NDDIC was established to increase knowledge and understanding about digestive diseases.

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