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Diagnosing Lynch Syndrome (HNPCC)

Genetic Testing

Genetic testing will indicate whether or not you have a mutation in your genes that indicate you have HNPCC. If you have learned through testing that you have HNPCC, then colorectal cancer screening is necessary.

Screening Examinations

The two screening examinations for colorectal cancer, and HNPCC, are sigmoidoscopy and colonoscopy.

Sigmoidoscopy

A sigmoidoscopy is a diagnostic procedure that allows the physician to examine the lower one-third of the large intestine. A short, flexible, lighted tube, called a sigmoidoscope, is inserted into the intestine through the rectum into the lower part of the large intestine. Air is injected into the intestine through the sigmoidoscope to inflate it for better viewing.

Colonoscopy

Colonoscopy is a diagnostic procedure that allows the physician to examine the entire length of the large intestine. An endoscope - a long, flexible, lighted tube (also called a colonoscope), is inserted through the rectum into the colon. In addition to allowing visualization of the internal colon, the colonoscope enables the physician to irrigate, suction, inject air, and access the bowel with surgical instruments. During a colonoscopy, the physician may remove tissue and/or polyps for further examination and possibly treat any problems that are discovered.

Form more information on colorectal and other cancers that can be caused by HNPCC:

Stanford Medicine Resources:

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