Changes in Oncology Care Provision Following Safety-Net Hospital Acquisition by Health Systems.

The impact of safety-net hospital (SNH) acquisition by health systems on specialty care delivery remains unclear, with important implications for access and equity. We examined how SNH acquisitions affect oncology service availability, volumes, and patient characteristics among Medicare fee-for-service beneficiaries using claims data from 2008 to 2019. We identified 75 SNH acquisitions from 2011 to 2015 and 151 independently operated SNHs as controls, estimating changes using a weighted stacked event study design. Following acquisition, chemotherapy volumes increased significantly by 99.6 annual claims (95% CI: [21.9, 177.3]), representing an 84% increase from baseline, while advanced imaging, radiation therapy, and cancer-directed surgical volumes showed no significant changes. We observed no changes in service line availability or patient demographics including race and ethnicity, dual eligibility, or age. These findings suggest system integration may lead to selective expansion of scalable or financially favorable oncology services without markedly altering overall service offerings or Medicare populations served by SNHs.