We analyzed tamoxifen use as a malignancy risk factor in women with endometrial polyps.
This retrospective study included 675 women who underwent hysteroscopic polypectomy in 2010 to 2015 at the University of Campinas. Women were divided into tamoxifen use (n = 169) and no tamoxifen use (n = 506) groups. The primary outcome was endometrial cancer prevalence. Dependent variables included age, parity, years since menopause, presence of abnormal uterine bleeding, endometrial pattern on hysteroscopy, and endometrial thickness.
There were seven cases of endometrial cancer in the tamoxifen use group (4.14%) and 41 in the no tamoxifen use group (8.1%; P = 0.083). On performing multivariate analysis, tamoxifen use was not a risk factor for endometrial cancer (prevalence ratio 0.51, 95% confidence interval [CI] 0.23-1.14, P = 0.101). The no tamoxifen use group had an increased prevalence of malignancy when women presented with abnormal uterine bleeding (prevalence ratio 3.9, 95% CI 2.08-7.29, P < 0.001), age >60 years (prevalence ratio 2.1, 95% CI 1.12-3.93, P = 0.021), or nulliparous status (prevalence ratio 3.13, 95% CI 1.55-6.35, P = 0.002). The tamoxifen use group had increased prevalence of malignancy when women were >60 years (prevalence ratio 7.85, 95% CI 1.05-58.87, P = 0.006) or nulliparous (prevalence ratio 8.36, 95% CI 2.32-30.11, P < 0.001).
Tamoxifen use was not related with a higher prevalence of endometrial cancer in women with endometrial polyps. Abnormal uterine bleeding, age > 60 years, and nulliparous status were associated with malignancy.