Use of bone scans during initial prostate cancer (CaP) workup, downstream procedures, and associated Medicare costs.

Abstract

5040 Background: Bone scans are not recommended in the routine workup for patients with apparent low and intermediate risk CaP. We quantified the use of bone scans in low and intermediate risk patients, uses of other imaging and procedures after the bone scan, and costs to Medicare. Methods: Patients in the Surveillance Epidemiology and End Results (SEER)-Medicare database diagnosed with CaP from 2004 to 2007 were included. PSA, Gleason score and clinical T stage were used to define D’Amico risk categories. Patients with metastatic disease were included because the decision to order a staging bone scan for patients with apparent low and intermediate risk cancers occurs before knowledge about metastasis. We report use of bone scans from the date of diagnosis to the earlier of treatment or 12 months. In patients who received bone scans, we report use of X-ray, CT, MRI, and bone biopsy following bone scan to the earlier of treatment or 12 months. Cost was estimated using Medicare reimbursement rates. Results: 28% and 47% of patients with apparent low- and intermediate-risk prostate cancer received a bone scan (Table); <1% of these patients were found to have metastatic disease after work-up. A high proportion of patients had other imaging studies or biopsies after bone scan. For low and intermediate risk patients, the combined cost to Medicare of bone scan, X-ray, and bone biopsy as part of initial workup is estimated at $11,000,000 per year. The cost from CT and MRI after bone scan costs Medicare approximately $15,400,000 per year. Conclusions: Overuse of bone scans is common in workup of apparent low and intermediate risk CaP, even with an almost 0% risk of metastatic disease. X-rays, bone biopsies, and perhaps additional scans such as CT and MRI may result from bone scan findings, which are mostly false positives for these patients. These unnecessary procedures are costly to Medicare. [Table: see text]