Risk Factors for Endometrial Lesions Detected by Hysteroscopy in Breast Cancer Patients Taking Tamoxifen

Abstract

Background Breast cancer has become the most common malignant tumor threatening the health of Chinese women in recent years. The use of tamoxifen (TAM) has successfully reduced the recurrence and progression of estrogen receptor-positive breast cancer, however, it also increases the risk of endometrial lesions. Objective To explore the risk factors for endometrial lesions in breast cancer patients taking TAM, determine the optimal threshold value of endometrial thickness, and improve the positive detection rate of hysteroscopy. Methods Breast cancer patients taking TAM (20 mg/d) who underwent hysteroscopic endometrial biopsy admitted to the Department of Gynecology of the First Affiliated Hospital with Nanjing Medical University from January 2015 to January 2022 were retrospectively selected as the study objects and divided into the negative hysteroscopic endometrial biopsy group (normal endometrium) and positive hysteroscopic endometrial biopsy group (endometrial lesions including endometrial polyps, endometrial hyperplasia without atypia, endometrial atypical hyperplasia and endometrial carcinoma). Clinical data of the patients were collected, including age, BMI, history of hypertension and diabetes, delivery times, presence of menopause and abnormal uterine bleeding/postmenopausal bleeding (AUB/PMB), receiving of chemotherapy, duration of TAM treatment, use of gonadotropin-releasing hormone agonists (GnRH-a), endometrial thickness, echo features of intrauterine lesions. Multivariate Logistic regression analysis was used to explore the risk factors for endometrial lesions in breast cancer patients taking TAM. The receiver operating characteristic (ROC) curve of endometrial thickness for predicting endometrial lesions detected by hysteroscopy was plotted, and the area under the ROC curve (AUC) and its 95%CI were calculated to determine the optimal cut-off value of endometrial thickness for receiving hysteroscopic surgery. Results The proportion of patients with AUB/PMB, duration of TAM treatment≥24 months, intrauterine hyperechoic lesions and endometrial thickness in the positive hysteroscopic endometrial biopsy group were higher than those in the negative hysteroscopic endometrial biopsy group (P<0.05). Multivariate Logistic regression analysis showed that AUB/PMB〔OR=7.731, 95%CI (1.949, 30.699), P=0.004〕, endometrial thickening〔OR=1.223, 95%CI (1.091, 1.371), P=0.001〕 and intrauterine hyperechoic lesions〔OR=13.383, 95%CI (2.751, 65.103), P=0.001〕were independent risk factors for endometrial lesions detected by hysteroscopy in breast cancer patients taking TAM. The AUC of endometrial thickness for predicting endometrial lesions detected by hysteroscopy in breast cancer patients taking TAM was 0.753〔95%CI (0.638, 0.868), P<0.001〕, with the Youden index of 0.54, optimal cut-off value of 9.15 mm, sensitivity and specificity of 0.755 and 0.786, respectively. Conclusion The risk of endometrial lesions is increased in breast cancer patients taking TAM with AUB/PMB, endometrial thickness≥9.15 mm suggested by ultrasound and intrauterine hyperechoic lesions, when the hysteroscopy and endometrial biopsy should be actively considered.

Keywords

• breast neoplasms|tamoxifen|endometrial hyperplasia|hysteroscopy|endometrial lesions|endometrial thickness|risk factors