Time-Driven, Activity-Based Cost Analysis of Radiation Treatment Options for Spinal Metastases

Several treatment options for spinal metastases exist, including multiple radiation therapy (RT) techniques: three-dimensional (3D) conventional RT (3D-RT), intensity-modulated RT (IMRT), and spine stereotactic radiosurgery (SSRS). Although data exist regarding reimbursement differences across regimens, differences in provider care delivery costs have yet to be evaluated. We quantified institutional costs associated with RT for spinal metastases, using a time-driven activity-based costing model.

Comparisons were made between (1) 10-fraction 3D-RT to 30 Gy, (2) 10-fraction IMRT to 30 Gy, (3) 3-fraction SSRS (SSRS-3) to 27 Gy, and (4) single-fraction SSRS (SSRS-1) to 18 Gy. Process maps were developed from consultation through follow-up 30 days post-treatment. Process times were determined through panel interviews, and personnel costs were extracted from institutional salary data. The capacity cost rate was determined for each resource, then multiplied by activity time to calculate costs, which were summed to determine total cost.

Full-cycle costs of SSRS-1 were 17% lower and 17% higher compared with IMRT and 3D-RT, respectively. Full-cycle costs for SSRS-3 were only 1% greater than 10-fraction IMRT. Technical costs for IMRT were 50% and 77% more than SSRS-3 and SSRS-1. In contrast, personnel costs were 3% and 28% higher for SSRS-1 than IMRT and 3D-RT, respectively (P < .001).

Resource utilization varies significantly among treatment options. By quantifying provider care delivery costs, this analysis supports the institutional resource efficiency of SSRS-1. Incorporating clinical outcomes with such resource and cost data will provide additional insight into the highest value modalities and may inform alternative payment models, operational workflows, and institutional resource allocation.