Endometrial thickening in postmenopausal breast cancer patients taking tamoxifen: a cross-sectional study

To determine the prevalence of endometrial thickening (endometrial thickness > 5 mm) in postmenopausal breast cancer patients taking tamoxifen.

Cross-sectional descriptive study.

Srinagarind Hospital, Faculty of Medicine, Khon Kaen University.

Total of 37 postmenopausal breast cancer patients receiving 20-40 mg/day of tamoxifen treatment for at least 6 months were included in the study.

Thorough history taking and physical examination as well as transvaginal ultrasonography (TVS) were conducted in all patients.

Among the 37 patients included in this study, the mean age was 56.35 years. The mean body weight and mean body mass index was 60.88 kg and 26.03 kg/m2, respectively. The mean age at diagnosis of breast cancer was 51.84 years. The majority of patients (75.68%) had stage II disease while the rest of patients were diagnosed with stage III (16.22%), I (5.40%) and IV (2.70%), respectively. The mean +/- SD of endometrial thickness (ET) found in this study was 7.53 +/- 5.16 mm. The prevalence of thickened endometrium (defined as ET > 5 mm from TVS) was 59.46%. Other pelvic pathologies detected by ultrasonography were multiple small hypoechogenic areas in the endometrium (32.43%), and myoma uteri (5.41%).

The prevalence of thickened endometrium in postmenopausal breast cancer patients taking tamoxifen found in this study was extraordinarily high. Therefore it seems to be justified to propose a transvaginal ultrasound screening in all postmenopausal breast cancer patients taking tamoxifen to detect endometrial thickening and possibly pathologies which could be resulted from tamoxifen treatment.