Breast cancer recurrence risk after hormonal contraceptive use in survivors of reproductive age

Abstract

ObjectiveTo assess the risk of recurrence with hormonal contraceptive use in breast cancer survivors of reproductive age. Study designIn this retrospective study, women ages 18–51 years who were diagnosed with primary stage 0–3 breast cancer between 2006–2016 and subsequently entered remission were included. Patients with missing information within the cancer registry or electronic medical record and those with a history of hysterectomy and/or sterilization procedure prior to diagnosis were excluded. Hormonal contraception use was defined as being prescribed an oral contraceptive pill (OCP), patch, vaginal ring, medroxyprogesterone injection, etonogestrel implant, or levonorgestrel-releasing intrauterine device (IUD). Women were separated into two groups, hormonal contraceptive users and non-users. Basic descriptive and inferential statistics were used to compare groups as appropriate. The primary outcome reviewed was local or distant breast cancer recurrence. Secondary outcomes included all-cause mortality and pregnancy. ResultsFollowing exclusions, 1370 women remained in the cohort. Ninety-seven women (7.08 %) received a prescription for a form of hormonal contraception. When comparing groups, hormonal contraceptive users were more likely to be between 18−40 years of age (46.39 % vs. 17.99 % non-users;P < 0.01) and never smokers (68.04 % vs. 38.57 % non-users; P < 0.01). Patients did not differ between groups based on any other demographic or cancer-related characteristic, including tumor hormone receptor expression. Overall, 92 patients (6.72 %) experienced local or distant recurrence during the study period. Recurrence did not differ between groups (6.19 % users vs. 6.76 % non-users; P = 0.83). All-cause mortality and pregnancy rates also did not differ between hormonal contraceptive users and non-users. ConclusionThe study shows no increased risk of recurrence associated with hormonal contraceptive use after breast cancer diagnosis and remission.