Impact of Fertility Concerns on Tamoxifen Initiation and Persistence

BACKGROUND: Adjuvant tamoxifen reduces breast cancer recurrence risk and mortality; however, initiation and treatment persistence are poor for younger patients. We hypothesized that a unique set of factors, including fertility concerns, would contribute to the poor tamoxifen use among premenopausal patients. METHODS: From 2007 to 2012, 515 premenopausal patients younger than age 45 years, with stage 0 to III hormone receptor-positive breast cancer, for whom tamoxifen was recommended, were identified. Clinical and pathologic tumor characteristics, treatment regimens, and fertility concerns were recorded. Clinical factors associated with tamoxifen noninitiation and discontinuation were identified using univariate and multivariable analysis. After the recommendation for tamoxifen, patient reasons for tamoxifen noninitiation or discontinuation were also documented. All statistical tests were two-sided. RESULTS: Based on multivariable analysis, fertility concerns were statistically associated with both noninitiation (odds ratio = 5.04, 95% confidence interval (CI) = 2.29 to 11.07) and early discontinuation (hazard ratio = 1.78, 95% CI = 1.09 to 3.38) of tamoxifen. Other independent predictors of noninitiation included a diagnosis of ductal carcinoma in situ, declining radiation, and not receiving chemotherapy (stage I-III). Additionally, smoking and not receiving radiation therapy were statistically significant predictors of early withdrawal from therapy. Primary patient reasons for noninitiation and early discontinuation included concerns about side effects and fertility. CONCLUSION: This study provided insight into factors associated with tamoxifen use for reproductive-aged breast cancer survivors, with a new focus on fertility. Fertility concerns negatively impacted tamoxifen initiation and continuation among premenopausal patients. Interventions to optimize treatment initiation and persistence for young cancer patients should include access to fertility preservation options.