Analytic morphometrics: Assessing the role of sarcopenia and abdominal fat measurements in predicting survival for mRCC patients undergoing cytoreductive nephrectomy.

603 Background: Analytic morphomics have emerged as promising biomarkers of post-surgical outcomes. Decision-making in patients with mRCC is nuanced, as benefits of cytoreductive nephrectomy (CN) must be balanced against risks of delaying or forgoing systemic therapy. We sought to identify if pre-operative morphometrics predict survival in patients undergoing CN. Methods: We reviewed clinical, histopathologic, and radiographic data for patients who underwent CN at our institution from 2006-2012. Pre-operative cross-sectional images of T12 to L4 were assessed. Subcutaneous fat content (average distance from skin to fascia in midline); visceral fat (average distance from fascia to anterior vertebral body); and total body fat (visceral + subcutaneous fat) were quantitated. Psoas muscle area and density at L4 were indexed. Primary outcomes were OS and DSS. Results: 62 patients had complete data for review. Median age at surgery was 60 years (range 40-77), Charlson score was 1 (0-5), and ECOG PS was 0 (0-2). T...