Major Prognostic Role of Ki67 in Localized Adrenocortical Carcinoma After Complete Resection

Background: Recurrence of adrenocortical carcinoma (ACC) even after complete (R0) resection occurs frequently. Objective: The aim of this study was to identify markers with prognostic value for patients in this clinical setting. Design, Setting, and Participants: From the German ACC registry, 319 patients with the European Network for the Study of Adrenal Tumors stage I–III were identified. As an independent validation cohort, 250 patients from three European countries were included. Outcome Measurements and Statistical Analysis: Clinical, histological, and immunohistochemical markers were correlated with recurrence-free (RFS) and overall survival (OS). Results: Although univariable analysis within the German cohort suggested several factors with potential prognostic power, upon multivariable adjustment only a few including age, tumor size, venous tumor thrombus (VTT), and the proliferation marker Ki67 retained significance. Among these, Ki67 provided the single best prognostic value for RFS (hazard ratio...