Are endometrial polyps true cancer precursors?

OBJECTIVE: The purpose of this study was to assess whether endometrial polyps (EMPs) represent cancer precursors. STUDY DESIGN: Age standardized incidence ratios (SIRs) of histologically verified endometrial cancers (EmCas) were estimated in women with EMPs and in women with uterine leiomyomata, which is a condition that is unrelated to endometrial carcinogenesis. SIRs were calculated as the ratio of observed to expected EmCas based on age-specific incidence rates for female Montreal residents during the same period. RESULTS: Of 1467 women with EMPs, 125 (8.5%) had EmCa. Of 1138 patients with uterine leiomyomata, 133 (11.7%) had EmCa. The SIRs of EmCa for women with EMPs (odds ratio, 8.0; 95% confidence interval, 6.6-9.5) were significantly lower than that in women with leiomyomata (odds ratio, 19.1; 95% confidence interval, 16.0-22.6). Abnormal uterine bleeding was the main reason for evaluating patients with EMP with or without associated EmCa. CONCLUSION: The findings of higher EmCa incidence are consistent with enhanced detection opportunity rather than with the endometrial cancer precursor potential of EMPs.