Dedicated review of sarcoma pathology is necessary for corroborative diagnosis in nearly one half of referred patients.

Abstract

Specialized centers have been shown to improve survival and functional outcomes in patients with sarcoma. The objective of this study was to determine the rate and clinical impact of changes in pathologic diagnosis between high- and low-volume sarcoma centers. We performed a retrospective review of patients discussed at UCLA Multidisciplinary Sarcoma Conference over 1 year. Patients with a pathology report from an outside facility and subsequent formal UCLA pathology review were included. Of 1,350 cases and 877 unique patients presented, 196 patients were identified for analysis. The primary outcome was to assess concordance between pathologic diagnosis at high- and low-volume sarcoma centers. Concordance was defined as either full concordance, minor discordance, or major discordance between the original diagnosis and review by a sarcoma pathology specialist. Of the 196 patients who were included in this study, 44% had full concordance on review of their pathology, 12% had minor discordance, and 44% had major discordance. Major discordance included benign/malignant mismatch (n = 23/87, 26%), discrepancy in histologic subtype (n = 25/87, 29%), change from nondiagnostic to diagnostic (n = 34/87, 39%) and major grading discrepancy (n = 5/87, 6%). After excluding other high-volume centers (n = 18), the major discordance rate increased to 48% (n = 85/178). Nearly one half (44%) of patients had a major change to their diagnosis that would affect prognosis or treatment plan after referral to a high-volume sarcoma center. A coordinated system for pathologic re-review for all potential sarcoma diagnoses could facilitate optimal management of patients with these rare malignancies.