Abstract
BACKGROUND: Standard of care for glioblastoma multiforme (GBM) involves surgical resection plus chemoradiation. We recently published a survival model demonstrating personalized estimates of median survival that vary with patient-specific characteristics. We wished to build an econometric model to assess the costs of therapies for GBM. METHODS: Cost data from publicly available sources were used to construct a cost model based on our personalized predictor of GBM patient survival. We used the model to estimate median survival and cost of therapy for patients of various ages (40-90 years), Karnofsky Performance Scores (50-90), and extents of resection (0-100%). We analyzed surgery plus several adjuvant therapies (steroids, radiotherapy [XRT], temozolamide [TMZ], and XRT + TMZ). Cost effectiveness was calculated as cost per week of survival and cost per quality adjust life year (QALY). RESULTS: For surgery plus steroids, mean survival was 113 days (range 34-291), mean cost was $21,892 (range $15,167-23,782), mean cost per week of therapy was $1,614 (range $572-3,666), and mean cost/QALY was $130,149 (range $33,144-382,305). For surgery + XRT, mean survival was 155 days (range 46-399), mean cost was $35,017 (range $23,702-37,040), mean cost per week of therapy was $1,923 (range $552-4,283), and mean cost/QALY was $155,010 (range $32,009-446,611). For surgery + TMZ, mean survival was 184 days (range 48-476), mean cost was $58,732 (range $33,157-103,840), mean cost per week of therapy was $2,489 (range $1,527-5,440), and mean cost/QALY was $197,842 (range $88,472-472,753). For surgery + XRT + TMZ, mean survival was 253 days (range 76-653), mean cost was $82,018 (range $50,711-143,670), mean cost per week of therapy was $2,542 (range $1,541-4,695), and mean cost/QALY was $202,089 (range $89,283-489,670). CONCLUSION: Cost effectiveness of treatments for GBM is influenced by patient age, functional status, and extent of surgical resection. For many patients the estimated cost/QALY exceeds commonly-stated thresholds for cost-effective care, a finding that may inform future debate on GBM therapy.