Cost-Effectiveness Research and Radiation Oncology: An Analysis of the Published Literature

Abstract

Purpose/Objective(s): A previous decision analysis compared primary radiation therapy (RT) and androgen deprivation therapy (ADT) to radical prostatectomy (RP) for men 65 years old with resulting QALEs of 9.3 and 8.0 QALYs, respectively (Sher, Cancer, 2012). However, this analysis did not incorporate the use of curative-intent, salvage therapy for local recurrence or treatment cost. Materials/Methods: The base case was a 65 year-old man diagnosed with high-risk prostate cancer (T1c, GS 8-10, PSA >10). This decision analysis compared upfront RT + 2 years of ADT versus RP with selective postoperative RT + 2 years of ADT for postoperative risk factors. Salvage therapy included RP or RT, depending on initial treatment delivered. Assumptions were based on the highest-quality data available: post-operative risk factors from Partin Tables, biochemical failure (BF) post-RP from the Kattan nomogram, BF post-RP + RT + ADT from RTOG 96-01, BF post-RT + ADT from RTOG 92-02, and BF post-salvage RT or RP from retrospective analyses. Treatment-related effects including mortality, acute toxicity, and moderate-to-severe erectile dysfunction, gastrointestinal or genitourinary side effects were incorporated into calculations of QALY. Yearly, age-related mortality estimates were taken from CDC life tables. Costs were estimated from the payer’s perspective using Medicare reimbursements in 2011 United States dollars. A Markov model was developed to model chance events with yearly cycles until death. Microsimulation incorporated parameter uncertainty to estimate QALE while tracking individual patients’ disease history. Results: In the base case, the mean QALE was 10.25 (95% CI, 1.8-20) versus 10.22 (95% CI, 1.3-20) QALYs for RT + ADT versus RP, respectively. The mean cost of treatment was $40,863 (95% CI, 1,401-181,778) versus $36,144 (95% CI, 117-157,556) for RT + ADT and RP, respectively. The mean ICER for RP compared to RT + ADT is 15,578 (95% CI, 1,029,978 812,230). Cost-effectiveness acceptability suggests there is considerable uncertainty about which strategy is optimal. Conclusions: When incorporating salvage therapy for local recurrence of high-risk prostate cancer, there is no clear difference in QALE or ICER between RT + ADT versus RP as primary treatment strategies. Author Disclosure: J.A. Dorth: None. W.R. Lee: None. E.R. Myers: None.