Cancer Types


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Colon and Rectal Cancer Basic Information

Start with what is colon or rectal cancer?   Then read the NCI booklet, and the Cancer Net Patient sites for colon and rectum, and a review about the cause of colon and rectal cancer here and good patient information from up-to-date here and the other good colon and rectal cancer links.

Diet and cancer here.

And see what are the most common locations for cancer and here.    

Age and colon and rectal cancer.

Go here for a review on symptoms and evaluation.

Main colon and rectal anatomy section go here, and for pictures of CT or PET Scans go here

See the screening or prevention (here and here) or the section about genetics or hereditary colon cancer

Anatomy point: see detailed anatomy picture of the colon and rectum (and note that the rectum is below the peritoneal reflection pic #1 and pic#2) or a cancer on a barium enema.

Radiation is more commonly used for cancers of the rectum than colon. Measured from  the anal verge the anus is the most distal 4cm, the rectum is then from 4 to 16cm (12cm in length) the sigmoid starts at roughly 17cm and is about 40cm in length.( so extends 17 to 57cm from the anal verge.)

The typical sigmoidoscope only reaches the lower part of the colon



colonoscopy_adam.jpg (13940 bytes) One-Time Screening for Colorectal Cancer with Combined Fecal Occult-Blood Testing and Examination of the Distal Colon
D. A. Lieberman and Others  NEJM 2001:345:555-560

A total of 2885 subjects returned the three specimen cards for fecal occult-blood testing and underwent a complete colonoscopic examination. A total of 23.9 percent of subjects with advanced neoplasia had a positive test for fecal occult blood. Sigmoidoscopy identified 70.3 percent of all subjects with advanced neoplasia. Combined one-time screening with a fecal occult-blood test and sigmoidoscopy identified 75.8 percent of subjects with advanced neoplasia. Conclusions One-time screening with both a fecal occult-blood test with rehydration and sigmoidoscopy fails to detect advanced colonic neoplasia in 24 percent of subjects with the condition.