Risk of colorectal cancer death following adenoma removal greater in women vs men

There appears to be a sex-specific difference in the risk of colorectal cancer death after adenoma removal, with women being at higher risk than men, according to a study.

Researchers identified 40,293 individuals who had adenomas removed in Norway between 1993 and 2007, with follow-up through 2018. They calculated standardized incidence ratios (SIR) and incidence-based mortality ratios (SMR) for colorectal cancer in women and men using the female and male population comparators. High-risk adenomas were defined as ≥2 adenomas, villous component, or high-grade dysplasia.

Over a median follow-up of 13.0 years, 1,079 women (5.5 percent) and 866 men (4.2 percent) developed colorectal cancer. Of these, 328 women (1.7 percent) and 275 men (1.3 percent) died of their disease.

Analyses confirmed that the incidence of colorectal cancer was significantly greater in women (SIR, 1.64, 95 percent confidence interval [CI], 1.54–1.74) than in men (SIR, 1.12, 95 percent CI, 1.05–1.19). Meanwhile, colorectal cancer-related mortality was elevated only in women (SMR, 1.13, 95 percent CI, 1.02–1.26) and reduced in men (SMR, 0.79, 95 percent CI, 0.71–0.89).

Specifically, women with high-risk adenomas were at heightened risk of colorectal cancer death (SMR, 1.37, 95 percent CI, 1.19–1.57). The risk was similar among women with low-risk adenomas (SMR, 0.90, 95 percent CI, 0.76–1.07) and men with high-risk adenomas (SMR, 0.89, 95 percent CI, 0.76–1.04) but much lower among men with low-risk adenomas (SMR, 0.70, 95 percent CI, 0.59–0.84).

The findings suggest the consideration of sex-specific surveillance recommendations after adenoma removal.