Association between physician characteristics and the use of 21-gene recurrence score genomic testing among Medicare beneficiaries with early-stage breast cancer, 2008-2011.

PURPOSE: We sought to determine whether physician-level characteristics were associated with 21-gene recurrence score (RS) genomic testing to evaluate recurrence risk and benefit of adjuvant chemotherapy in patients with estrogen receptor-positive, node-negative breast cancer. METHODS: Retrospective cohort study of a nationally representative sample of Medicare beneficiaries using Surveillance, Epidemiology, and End Results program-Medicare data linked with the American Medical Association physician master file. The main outcome was receipt of genomic testing within 1 year of diagnosis as a function of physician-level factors. RESULTS: A total of 24,463 patients met the study criteria; they received care from 3172 surgeons and 2475 medical oncologists. Of 4124 tests ordered, 70% were ordered by a medical oncologist and 16% by a surgeon. In multivariable regression models, multiple variables were associated with receipt of testing, including having a medical oncologist (odds ratio [OR] 2.77; 95% CI 2.00-3.82), a surgeon specializing in surgical oncology (OR 1.20; 95% CI 1.09-1.31), and a female medical oncologist (OR 1.10; 95% CI 1.02-1.20). Having a medical oncologist with 5 or more years in practice was associated with lower odds of testing (OR 0.83; 95% CI 0.76-0.92). Surgical procedures performed at academic centers were associated with higher odds of testing (OR 1.11; 95% CI 1.02-1.20). CONCLUSIONS: Although most RS testing was ordered by medical oncologists, physicians in other specialties ordered roughly one-third of the tests. Physician characteristics, including gender and time in practice, were associated with receiving testing, creating opportunities for targeting interventions to help patients receive optimal care.

Duke Scholars

Author Michaela Ann Dinan Population Health Sciences