Abstract P1-15-07: Evaluation of menopausal status among breast cancer patients with chemotherapy-induced amenorrhea: A prospective study in China
Authors: Zhang B , Zheng R , Zhang Q , Wang X 
Published: February 2018

Abstract
Background
Many pre-menopausal patients faced an unclear status of menstruation after chemotherapy, which makes it difficult for oncologists to determine the endocrinotherapy plan. This study aimed to establish a model that predicts and classifies the menstruation status of patients with CIA (chemotherapy-induced amenorrhea).
Methods
This is a hospital-based prospective study of female breast cancer patients. Inclusion criteria included patients diagnosed with breast cancer with a complete medical record of menses. Multivariate models were adjusted for established and potential confounding factors including age, serum concentration of estradiol (E2) and follicle-stimulating hormone (FSH), feeding, pregnancy, parity, abortions, and body mass index (BMI). The hazard ratios and 95% confidence intervals of different risk factors were estimated.
Results
From 2013 to 2016, 1,796 breast cancer patients were included in this study. Among them, 1,175 (65.42%) were pre-menopausal and 621 (34.58%) were post-menopause. The average age of natural menopause was 49.99 ± 3.24.
550 patients were included in CIA analysis, and 449 patients (81.64%) had CIA. As patients older than 60 years were defined as post-menopausal and low proportion of post-menopausal patients among people under 45 years old (4.83%), the target population of menopausal status estimation of patients focused on 1,142 patients aged 45 to 60 years old in this study. Age was found to be associated with menopausal status (OR: 1.856, 95% CI: 1.732-1.990). Other factors included, serum concentrations of E2 (OR: 0.976, 95% CI: 0.972-0.980) and FSH (OR: 1.060, 95% CI: 1.053-1.066), menarche age (OR: 1.074, 95% CI: 1.009-1.144) and number of abortions (OR: 0.829, 95% CI: 0.736-0.933). According to multivariate analysis, menopausal status was correlated with age, serum concentration of E2 and FSH. The model is: Logit (p) = -28.396+0.536Age-0.014E2+0.032FSH. When P is greater than 0.5, then the patient's menstrual state will be classified as post-menopausal. The areas under the ROC curve (AUC) were 0.9220, 0.8561 and 0.8769, respectively for the single factors of age, E2 and FSH, but the comprehensive model's AUC reached 0.9678. To examine the performance of this model, sensitivity analyses and model validation were conducted using external validation cohort (n=3,073), Leave-One-Out Cross Validation test, 10%, 20%, 30%- fold cross validation check, and Back substitution check. The results show that the sensitivities for different methods were about 85%, and the specificities were higher than 89%.
According to the estimation of National Center Cancer Registry of China and the result of a national-wide Chinese retrospective study, about 137.7 thousands newly diagnosed female breast cancer aged 45-60 each year. Among them, 30.72% was hormone receptor positive, and 41.4 thousands (14.85%) patients annually probably be influenced by chemotherapy and decisions regarding endocrine therapy must be concerned.
Conclusions
The discriminative model obtained from this study for predicting menstrual state is important for pre-menopausal breast cancer patients with CIA. This model has high levels of specificity and sensitivity. A large numbers of patients probably be benefited from this study.
Citation Format: Zhang B, Zheng R, Zhang Q, Wang X. Evaluation of menopausal status among breast cancer patients with chemotherapy-induced amenorrhea: A prospective study in China [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-15-07.