"I was diagnosed with stage IIA colorectal cancer last August, a few months before my 31st birthday...I worry because few people develop this cancer as early as I did. There is no history of cancer in my family. I have been a lacto-ovo vegetarian since I was 18 years old. Do you have any recommendations for how I can prevent recurrence? Could this have been a fluke?"
Differences in Colorectal Cancer in the Young and Old
There is a slight correlation between age at diagnosis and the types of genetic mutations present in colorectal cancer. Cancer in younger people also tends to occur more often on the right side of the colon than the left. We used to think that colorectal cancers in younger people were more aggressive, but this has not proven to be the case. These slight differences don't change the fact that most people diagnosed with colorectal cancer do not have a family history of it and do not have an inherited syndrome associated with it.Prevention
The problem faced currently is diagnosis of precancerous polyps and cancers in people under the age of 50 who have no family history, because people in this category are not generally being screened with endoscopy. The guidelines for screening put forth by every major organization with an interest in this area do not recommend screening colonoscopy or sigmoidoscopy in this group of patients. For this reason, we rely on this group of patients to be evaluated when they have symptoms that suggest a potential problem such as blood in the stool, unintentional weight loss, loss of appetite, or chronic anemia. Many investigators are working on DNA tests that would help to identify patients at higher risk of colorectal cancer, but these are still early in development.At the current time, the ways of preventing polyps and colorectal cancer do not differ between young and old patients. Regular surveillance with endoscopy if a patient has a history of colon cancer or polyps is critical. In addition, patients with a history of breast, ovarian, endometrial cancer, or inflammatory bowel disease may be at higher risk for colon cancer and should be screened. All patients with a family history, personal history, or other risk factors for polyps or cancer should discuss with their physician the appropriate tests and intervals for cancer surveillance. In the abscence of risk factors, most organizations recommend initial screening of the colon at age 50.
For chemoprevention, see the previous blog, Chemoprevention and Colorectal Cancer.
