In order to assess the hysteroscopic, histopathologic, and ultrasonographic aspects of uterine monitoring in postmenopausal breast cancer patients with or without abnormal uterine bleeding (AUB), as well as to calculate the risk of endometrial cancer in women with or without AUB.

20-25% of postmenopausal women undergoing tamoxifen (TAM) therapy develop polyps, according to recent studies. Many large (>2 cm) and molecularly changed uterine polyps are usually seen in these women. Furthermore, a number of studies have demonstrated that TAM therapy raises the risk of endometrial cancer in both premenopausal and postmenopausal women. Studies suggest that women who use TAM may also have an increase in the prevalence of uterine sarcomas. In addition, the duration of TAM administration appears to increase the risk of endometrial cancer and uterine sarcoma.

This multicentric cohort study will compare the ultrasonographic, hysteroscopic, and histopathologic findings in postmenopausal women treated for breast cancer with or without AUB in order to increase the robustness of a still ambiguous literature on the subject. It will estimate the risk of endometrial cancer in women with AUB according to various covariates related to the breast neoplasm or the ultrasonographic and hysteroscopic features.

Inclusion Criteria:

• In case of AUB: ultrasonographic endometrial thickness >5 mm at transvaginal ultrasound
• In case of non-AUB group ultrasonographic suspicion of endometrial or myometrial abnormalities

Exclusion Criteria:

• severe comorbidities (cardiovascular, metabolic, endocrine, and immunological disorders)
• receiving any other form of pharmacologic therapy

Women undergoing gynecological examinations for endometrial surveillance related to selective estrogen receptor modulators, aromatase inhibitors or other hormone therapy for breast cancer