Objective: The goal of this study was to evaluate the true prevalence of endometrial pathology in asymptomatic postmenopausal estrogen receptor–positive (ER-positive) breast cancer patients and to know whether some patients are particularly at risk.
Methods: A preliminary cross-sectional study was carried out with 130 postmenopausal ER-positive breast cancer patients. Before any treatment, diagnostic hysteroscopy and endometrial biopsy were performed in all women. Histopathological findings were considered the gold standard in estimating the prevalence of endometrial disease, which was analyzed according to different risk factors.
Results: Hysteroscopic evaluation was possible in 118 patients (90.7%). Of these patients, 68.6% were older than 60 years, and 51.4% were obese. Endometrial polyps were found in 35 patients (29.6%; 1 polyp with simple hyperplasia), and simple endometrial hyperplasia was found in 1 patient (0.8%), with an overall morbidity of the endometrium of 31.3%. Among all the well-established individual risk factors for endometrial pathology, only patient age, body mass index, and time since menopause were significant predictors of endometrial pathology and/or polyps. There was no statistical difference in the thicknesses of the endometrial lining, but many patients with an endometrial lining of less than 4 mm had polyps of less than 5 mm.
Conclusions: Asymptomatic postmenopausal women with ER-positive breast cancer have a very high prevalence of baseline subclinical endometrial abnormalities. Therefore, endometrial screening before tamoxifen treatment may be useful in all of these patients, and we believe that it should be performed by hysteroscopy in patients at high risk (obese and older women).