Acceptance of adjuvant chemotherapy recommendations in early-stage hormone-positive breast cancer.

Background: The role of systemic chemotherapy in early-stage, estrogen receptor (ER)-positive, and Her2-negative breast cancer remains an area of active investigation. The decision to recommend chemotherapy is multifactorial, and some patients decline recommended chemotherapy. We sought to identify patient factors leading to refusal of adjuvant therapy.

Materials And Methods: Data were collected from National Comprehensive Cancer Network Outcomes database and used to identify patients with primary, unilateral, T1-T2, N0, ER+, Her2-disease diagnosed from 2005-2011. Patient and clinical characteristics were analyzed for associations with physician recommendation for chemotherapy and patient acceptance of chemotherapy. A logistic regression model was used to identify patient and tumor characteristics associated with recommendation for and acceptance of chemotherapy.

Results: A total of 329 patients were identified. Chemotherapy was recommended in 191 patients (58.1%) and not in 138 (41.9%). Young age (odds ratio [OR]: 3.9, 95% confidence interval [CI]: 1.2-12.7), large tumor size (6.69, 95% CI: 3.31-13.5), and high Oncotype DX scores (11.2, 95% CI: 4.5-27.9) were more likely to receive a recommendation. About 71 patients (37.1%) refused chemotherapy. Patients younger than age 50 (20.9, 95% CI: 2.5-172.0), larger tumor size (3.4, 95% CI: 1.3-8.7), Oncotype DX score > 31 (31.3, 95% CI: 3.3-295.0), privately insured (8.2, 95% CI: 1.9-34.7), and Hispanic ethnicity (5.2, 95% CI: 1.6-16.8) were more likely to accept chemotherapy.

Conclusions: Physician recommendations for adjuvant chemotherapy for early-stage ER + breast cancer varied by commonly considered factors. Patient acceptance varied by similar factors but was also influenced by race and insurance status. This may be explained by cultural or social factors not well understood or not overcome by physician guidance.