Endometrial pathology in breast cancer patients: Effect of different treatments on ultrasonographic, hysteroscopic and histological findings

Breast cancer patients have an increased risk of endometrial pathology. To investigate whether the incidence of endometrial abnormalities and their clinicopathological features were affected by receiving tamoxifen (TAM), non‑-steroidal aromatase inhibitors (AIs) or no treatment (NT), 333 peri/postmenopausal breast cancer patients, who were referred to the Department of Gynecological, Obstetrical Sciences and Reproductive Medicine for gynecological assessment, were reviewed retrospectively. Transvaginal ultrasonographic (TVUS), hysteroscopic and histological findings were investigated. Endometrial histological findings included: atrophy in 61, 94.3 and 55.6% of cases in the TAM, AIs and NT groups, respectively; polyps in 30.9, 31.4 and 42.2% of cases in the TAM, AIs and NT groups, respectively; hyperplasia in 3% of patients in the TAM group and 11.1% of patients in the NT group; and cancer in 3.8% of cases in the TAM group and 11.1% of cases in the NT group. There was a significant correlation between the duration of TAM treatment and the severity of endometrial pathology. In all groups, there was a significant correlation between hysteroscopic and histological findings with regard to the diagnosis of endometrial atrophy, polyps, hyperplasia and cancer (P<0.001). In conclusion, these data revealed that there was a higher incidence of endometrial pathology in the NT group compared with the TAM group, which was significant for endometrial hyperplasia and cancer. The chance of developing high-risk histological subtypes of endometrial cancer was independent of TAM use. Lastly, although there was no significant difference in recurrent vaginal bleeding and mean endometrial thickness between the TAM and AIs groups, patients receiving AIs did not exhibit hyperplastic, dysplastic or neoplastic changes in the endometrium. This study indicates that breast cancer patients require screening for endometrial pathology; TVUS alone is useful in asymptomatic patients, however, in patients where the endometrial line is irregular or its thickness is >3  mm, hysteroscopy with directed biopsy is the appropriate diagnostic method.