Impact of overall survival (OS) as a function of facility caseload on feasibility of referral of radical prostatectomy (RP) to higher volume facilities.
363 Background: We recently reported a significant all-cause mortality (ACM) risk reduction associated with higher annual caseload for RP (PMID 31398279). Four volume groups (VG) were defined as VG1: <50th, VG2: 50th-74th, VG3: 75th-89th and VG4: top 10 percentile of caseload. The adjusted OS difference between VG1 and VG4 at 90th percentile survivorship reached 13.2 months, HR 1.30 (p<0.0001). Here we explore this economics of referral to VG4. Methods: Using a Markov model, we designed 4 scenarios (Sc) where 100,000 RPs were performed. In Sc 1 all RPs were performed at VG1; in Sc 2, 3 & 4, all RPs were performed at VG2, 3 &4 respectively. Subjects were followed for up to 20 years after RP. Survival and costs of care for each Sc were recorded. Probabilities of PSA recurrence (PSAR), development of metastatic disease (Met), cancer specific mortality (CSM) and ACM were adjusted for each VG according to the published HRs. Savings resulting from fewer recurrences, avoidance of salvage radiation therapy (SRT) and management of fewer Met were calculated. Standard discounting at 3% were applied to costs and benefits. Survival benefit and costs savings associated with making referrals from VG1, VG2, or VG3 centers to VG4 center were calculated. Using a willingness to pay (WTP) of $50K per life years gained (LYG), the maximum referral costs (MRC) were calculated. Results: Referral from a VG1 to a VG4 center was associated with highest OS benefit of 720 LYG at 20 years of follow up per 1000 referrals (PKR). Within a WTP of $50K, MRC of up to $37K was cost effective- Table. Conclusions: Given the survival benefit associated with performing RP at facility with high annual caseload, significant resources could be allocated to making a referral possible while still remaining within cost effectiveness boundaries.[Table: see text]