The role of facility variation on racial disparities in use of hypofractionated whole breast radiotherapy
Laucis AMB, Jagsi R, Griffith KA, Dominello MM, Walker EM, Abu-Isa EI, Dilworth JT, Vicini F, Kocheril PG, Browne CH, Mietzel MA, Moran JM, Hayman J, and Pierce LJ. The role of facility variation on racial disparities in use of hypofractionated whole breast radiotherapy. J Clin Oncol 2019; 37.
J Clin Oncol
Background: Concerns about racial disparities in the adoption of medical advances motivate investigation of the use of hypofractionated radiotherapy, a less burdensome and less costlyapproach that is efficacious for most patients with early-stage breast cancer. Methods: A prospectively collected statewide quality consortium database from 25 institutions was queried for breast cancer patients who completed hypofractionated (HF) or conventionally fractionated whole breast radiotherapy (RT) from 1/2012-12/2018. We used patient-level multivariable modeling to evaluate associations between HF use and race, controlling for patient and facility factors, and multilevel modeling to account for patient clustering within facilities. Results: Of 10,318 patients analyzed, 80% self-reported their race as White, 18% as Black, and 2% as Asian, similar to statewide and national distributions. 31% of Whites were treated at academic centers compared to 65% of Blacks and 65% of Asians. In 2018, HF was utilized in 75% of Whites versus 60% of Blacks and 68% of Asians. On patient-level multivariable analysis (see Table), Black and Asian race were significantly associated with a lower likelihood of HF receipt, despite accounting for treatment year, age, laterality, BMI, breast volume, comorbidities, stage, triple-negative status, IMRT use, academic center treatment, and 2011 ASTRO Hypofractionation Guideline eligibility. On multilevel analysis, race was no longer significantly associated with HF receipt. Conclusions: We observed thatBlack and Asian patients receive hypofractionated RT less often, despite more frequent treatment at academic centers. Multilevel modeling eliminated this disparity, suggesting that differences in facility-specific HF use may contribute. Further inquiry is needed to determine if reduction of facility-level variation may reduce disparities in accessing HF treatment.