Quantifying institutional resource utilization of adjuvant brachytherapy and intensity-modulated radiation therapy for endometrial cancer via time-driven activity-based costing

The purpose of this study was to quantify the cost of resources required to deliver adjuvant radiation therapy (RT) for high- to intermediate-risk endometrial cancer using time-driven activity-based costing (TDABC). Comparisons were made for three and five fractions of vaginal cuff brachytherapy (VCB), 28 fractions of intensity-modulated radiation therapy (IMRT), and combined modality RT (25-fraction IMRT followed by 2-fraction VCB). Process maps were developed representing each phase of care. Salary and equipment costs were obtained to derive capacity cost rates, which were multiplied by process times and summed to calculate total costs. Costs were compared with 2018 Medicare physician fee schedule reimbursement. Full cycle costs for 5-fraction VCB, IMRT, and combined modality RT were 42%, 61%, and 93% higher, respectively, than for 3-fraction VCB. Differences were attributable to course duration and number of fractions/visits. Accumulation of cost throughout the cycle was steeper for VCB, rising rapidly within a shorter time frame. Personnel cost was the greatest driver for all modalities, constituting 76% and 71% of costs for IMRT and VCB, respectively, with VCB requiring 74% more physicist time. Total reimbursement for 5-fraction VCB was 40% higher than for 3-fractions. Professional reimbursement for IMRT was 31% higher than for 5-fraction VCB, vs. IMRT requiring 43% more physician TDABC than 5-fraction VCB. TDABC is a feasible methodology to quantify the cost of resources required for delivery of adjuvant IMRT and brachytherapy and produces directionally accurate costing data as compared with reimbursement calculations. Such data can inform institution-specific financial analyses, resource allocation, and operational workflows.