History of oral contraceptive use in breast cancer patients: impact on prognosis and endocrine treatment response

Abstract

The purpose was to study oral contraceptive (OC) use in relation to breast cancer events and endocrine treatment response in a prospective population-based cohort, because it is unclear whether history of OC use impacts on prognosis in breast cancer patients. Between 2002 and 2011, 994 primary breast cancer patients without preoperative treatment were enrolled in Lund, Sweden and followed until December 2012. History of OC use was obtained from preoperative questionnaires. Tumor characteristics, clinical data, and date of death were obtained from pathology reports, patient charts, and population registries. Among the 948 patients with invasive cancer and no metastasis detected on the post-operative screen, 74 % had ever used OCs. Patients were followed for up to nine years (median follow-up 3 years), and 100 breast cancer events were recorded. Ever OC use was not associated with prognosis, irrespective of duration. However, any OC use before age 20 was associated with a threefold increased risk for breast cancer events in patients <50 years but not in patients ≥50 years (P interaction = 0.009). In patients ≥50 years with estrogen receptor positive tumors, previous OC use at any age was associated with a significantly decreased risk of breast cancer events among patients who received aromatase inhibitors compared to patients who never used OCs (adjusted HR 0.37: 95 % CI 0.15-0.87). OC use was not associated with tamoxifen-response. If confirmed, history of OC use may yield valuable prognostic and treatment predictive information in addition to currently used criteria.

The prognostic impact of COX‐2 expression in breast cancer depends on oral contraceptive history, preoperative NSAID use, and tumor size

“…OC use prior to age 20 years was significantly associated with lower COX‐2 expression in the present study and low COX‐2 expression was associated with worse short‐term prognosis. In line with this, OC use prior to age 20 years was previously reported to be associated with a worse prognosis among patients younger than 50 years in this cohort . Early OC use may carry long‐term impact on the tumor environment.…”

“…However, any history of OC use prior to diagnosis, and not early OC use modified the association between COX‐2 expression and prognosis. Ever OC use was also associated with improved prognosis among AI‐treated patients 50 years or older in the previous study . However, there was no association between COX‐2 expression and prognosis in AI‐treated patients in the present study.…”

Prognostic Impact of Menopausal Hormone Therapy in Breast Cancer Differs According to Tumor Characteristics and Treatment

“…A prior study using the same cohort has shown that smoking is associated with a higher risk of recurrence and death among AI-treated patients (31). A different study performed within the BCBlood study showed that ever a history of oral contraceptives use led to a lower risk of recurrence among AI-treated patients than non-users of oral contraceptives (43). The interaction between MHT and AI treatment was still significant when adjusted for smoking and ever oral contraceptive use.…”

State of the evidence 2017: an update on the connection between breast cancer and the environment

“…Women who had begun use before the age of 20 and were older than age 50 at the time of diagnosis showed no increased risk compared to age similar cases who began use later (HR = 0.70; 95% CI = 0.33–1.46). Women in this study took contraceptives for an average of 6 years, although the duration of use varied from 2 ½ to 12 years [ 169 ].…”