If you’ve recently turned 50, your doctor has likely recommended you get a colonoscopy. Fifty is the magic age at which people with average risk of colorectal cancer are supposed to be routinely screened for adenomas, abnormal growths that could over time become cancerous. Such growths are removed when detected, long before they might become malignant.

But a new study questions whether 50 is the optimal age for that first colonoscopy after all -- and whether men and women should be screened at different ages.

The research, published Wednesday in the Journal of the American Medical Association, examined data for 44,350 people who’d been screened for colon cancer in Austria between 2007 and 2010.

Among the key findings, men were seen to develop adenomas and advanced adenomas (AAs), growths most likely to become cancerous, far earlier than women did. The prevalence of AAs among men ages 45 to 49 was similar to that among women 55 to 59. In turn, the prevalence of colorectal cancer among 55-year-old men was comparable to that among 65-year old women.

Those numbers suggest that men may need screening earlier in life than women. The current age-50 guideline is based on the facts that precancerous colorectal growths typically take about 10 years to become cancerous and that the prevalence of colorectal cancer increases sharply at age 60. The new data seem to suggest that men should be screened closer to age 45 and women closer to age 55.

The authors say more study, including clinical research, is needed before such a shift can be recommended.