Cancer of the colon

Cancer Of. the Colon • Major public health problem • In developed countries • epidemiologists, molecular biologists, nutritionists, • gastroenterologists, prevention experts, surgeons, radiation • therapists, nurses, medical oncologists,

Gross Anatomy • Colon and the rectum • intraperitoneal or extraperitoneal.

• rectal cancers, which usually have no serosal covering and are surrounded by fat, bone, nerves, blood vessels, and viscera

Gross Anatomy • The cecum, transverse colon, and sigmoid loop are the intraperitoneal portions of the colon • Ascending colon, descending colon, splenic and hepatic flexures, sigmoid colon -surface in the retroperitoneum.

Epidemiology • Third in frequency in men and second in women • fourth leading cause of cancer mortality • better prognosis than more common cancers.

• 5-year survival rate of 41% to 42%

Etiology • Genetic change in the epithelial cells of the colonic mucosa.

• Mutagen exposure and genetic constitution • Reduced glutathione S-transferase (GSH transferase), DT-diaphorase, and Nacetyltransferase..

Fecal Mutagens • fecapentaenes, 3-ketosteroids, and heterocyclic amines • Changes in the fecal microflora • Altering extracellular superoxide formation.

• Intake of antioxidants • Changes in intestinal transit

Etiology • • • • • • •

Meat Intake Bile Acids Vitamin and Mineral Intake Fecal pH tobacco and alcohol use Dietary Factors Hormone Replacement in Women

Clinical Risk Factor