Men need colon cancer screening earlier than women: Study

By Dr. Ananya Mandal, MDSep 28 2011

A new study finds that men are at a higher risk of colon cancer than women and should get their first colonoscopy to screen for the disease at age 45, five years earlier than the current recommendation.

Researchers found that men were 1.8 times more likely than women to have advanced adenomas, which are polyps or lesions most susceptible to turning malignant, and twice as likely to have colon cancer. The findings also showed that men got precancerous polyps and colon cancers 10 years earlier than women, according to the study published today in the Journal of the American Medical Association.

“We have to create awareness for the sex-specific differences and have to underline the value of early screening colonoscopy,” said Monika Ferlitsch, lead author of the study and associate professor of medicine at the Medical University of Vienna. Ferlitsch said men have higher rates of colon cancer and precursor lesions, or polyps, than women because of a combination of lifestyle causes and genetics. Women should still get their first colonoscopy at age 50, the current recommendation, she warned.

Researchers in the study looked at 44,350 people who were part of a national screening colonoscopy program in Austria from 2007 to 2010. They were looking for the most appropriate age for the first colonoscopy to occur in both men and women. Across all ages, 24.9% of men and polyps or lesions and 8% had advanced polyps, vs. 14.8% and 4.7% of women. Looking at colon cancer itself, the incidence was 1.5% among men and 0.7% in women.

More studies are needed to look at the effectiveness of implementing sex-specific screening guidelines based on the development of colorectal cancer and deaths from the disease in the general population, said Ferlitsch, who heads the Quality Assurance Working Group for the Austrian Society for Gastroenterology and Hepatology.

More than 141,000 people in the U.S. will be diagnosed with colorectal cancer this year and almost 50,000 will die from the disease, according to the American Cancer Society. The numbers of men who get colon cancer and die from the disease are about 35 percent to 40 percent higher than women, according to the cancer society.

Only about half of people at least 50 years old who are recommended to have screenings actually get tested for colon cancer, according to the cancer society. Joel Brill, a gastroenterologist in Phoenix, Arizona, and chief medical officer of the American Gastroenterological Association's Digestive Health Outcomes Registry, said that there may be a benefit for starting colon cancer screenings earlier, though today's study alone shouldn't change at what age screening begins based on sex.

“Whether we recommend starting screening at age 45 or at age 50, it's important for physicians to educate their patients,” said Brill, who wasn't involved in the study. “If it comes down to one takeaway lesson it is screening is effective. The best test for colorectal cancer is the test that gets done. If we can get them screened, we can detect lesions, and if we can detect them and remove them before they become cancerous, we've won the battle.”

The U.S. Preventive Services Task Force recommends screening for adults aged 50 to 75 using a fecal occult blood test, sigmoidoscopy or colonoscopy. The American Cancer Society has similar recommendations. (People with a strong family history of the disease or other risk factors may be advised to start earlier.) In July the CDC credited colorectal-cancer screening with about half the decline in deaths from the disease seen over the last several years.