Screening colonoscopy finds more cancers in men

Colonoscopy detects cancers and advanced neoplasia at a higher rate in men than in women, according to a cross-sectional analysis of more than 50,000 participants in a Polish national colon cancer screening program.

The findings suggest that screening guidelines should include male sex as a risk factor. The Maria Slkodowska-Curie Memorial Cancer Center, Warsaw, and colleagues analyzed data from 43,042 people aged 50-66 years and 7,106 people aged 40-49 years who had reported a family history of any type of cancer. Participants had been referred by general or family physicians at any of 40 sites in Poland and were excluded if they had colon cancer or clinical signs thereof, or a colonoscopy within the last 10 years.

In the younger cohort, colonoscopy detected 124 advanced neoplasias (ANS) in 2.8% of women and 4.5% of men. Similarly, in patients aged 50 years or older, colonoscopy detected AN in 4.5% of women and 8.5% of men. The number needed to screen to detect AN in the large bowel was lower for men than for women in all age groups: 30 vs. 52, respectively, in the 40- to 49-year-old age group, 18 vs. 31 in the 50-54 group, 12 vs. 23 in those 55-59 years old, and 10 vs. 19 in those aged 60-66 years. We identified male sex as an independent predictor of advanced neoplasia.

This finding suggests that the screening recommendations should be modified in order to ensure the maximal diagnostic yield of the screening and the optimal use of resources. Current screening guidelines, such as those from the American College of Gastroenterology and the U.S. Preventive Services Task Force, call for colonoscopy screening to begin at age 50 and do not make specific recommendations according to sex.