Colorectal/Colon Cancer
Colorectal cancer is a cancer of the colon or rectum, which starts in the digestive system. Cancer can develop in any of the four sections of the colon or in the rectum. Each of these layers has a wall that is composed of many layers of tissue. Tumors spread from the inner sheets of these walls and can grow into additional regions.
More than 95% of colon and rectal cancers are cancer of the cells that line the inside of the colon and rectum, or adenocarcinomas. The majority of colorectal tumors start out as a polyp, or a growth of tissue that begins in the lining and then spreads toward the middle of the colon and rectum.
Common symptoms of colorectal cancer include diarrhea, constipation, feeling your bowel doesn't empty completely, bloody stool, narrower stool, gas pains and cramps, spontaneous weight loss, fatigue, nausea, and vomiting. Other health problems can cause the same symptoms, but anyone with these symptoms should see a physician.
The four methods of treatment for colorectal cancer are surgery, radiation therapy, chemotherapy, and monoclonal antibodies, which are newer, targeted therapies. Treatment is based on the cancer stage. After determining the stage of the disease, a doctor may decide to use two or more types of treatment together, or one after the other.
An Introduction to the CEA Test in Colorectal Cancer
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Colon Cancer Alliance 
Nonprofit organization of colon and rectal cancer survivors, their families, caregivers, people genetically predisposed to the disease, and the medical community. Provides support and information for people affected by colorectal cancer.
National Cancer Institute — Diagrams and Summary
Government resource for the newly diagnosed including diagrams and helpful information; summary of definitions, stages, overview, and treatment options.
National Cancer Institute — Clinical Trials, Prevention and More
Government resource for clinical trials, tips on prevention, helpful tools for screening and testing, plus up-to-date statistics and research.
National Digestive Diseases Information Clearinghouse
Easy-to-read, illustrated guide to "What I need to know about colon polyps."
Medline Plus 
Developed by government agencies and other health organizations, this site contains information about drugs, an illustrated medical encyclopedia, lots of interactive patient tutorials, and the latest health news. Also features a "guide to healthy web surfing."
MayoClinic.com
Not-for-profit hospital offers an introduction for those newly diagnosed with cancer; includes step-by-step information about signs and symptoms, causes, risk factors, and screening techniques.
