Recurrence-free survival analysis in locally advanced pheochromocytoma: first appraisal.

Abstract

CONTEXT\nLocally advanced pheochromocytoma (LAP) behavior remains unknown.\n\n\nOBJECTIVE\nTo characterize this population and its recurrence-free survival (RFS).\n\n\nDESIGN\nA retrospective multicentric study run within the ENDOCAN-COMETE network and GTE from 2003 to 2018.\n\n\nSETTING\n11 French Referral centers.\n\n\nPATIENTS\nPatients with LAP as defined by capsular invasion, vascular invasion, adipose tissue invasion and/or positive locoregional lymph nodes at diagnosis without evidence of distant metastasis.\n\n\nMAIN OUTCOME MEASURES\nRecurrence was defined as the reappearance of the tumor, including local site and/or distant metastasis. The primary endpoint was RFS analysis. The secondary endpoints were characterization, overall survival (OS) and prognostic factors of recurrence.\n\n\nRESULTS\nAmong 950 patients, 90 exhibited LAP criteria (9%). 55 met the inclusion criteria (median age: 53 years-old, 61% males, 14% with a germline mutation, 84% with a catecholamine excess). LAP was defined by 31 (56%) capsular invasions, 27 (49%) fat invasions, 6 (11%) positive lymph nodes and 22 (40%) vascular invasions. After a median follow-up of 54 months (range, 6-180), 12 patients (22%) had recurrences and 3 (5%) died of a metastatic disease. Median RFS was 115 months (range, 6-168). The recurrences were local in 2 patients, distant in 2 and both local and distant in 8 patients. Median OS of patients was not reached. Size above 6.5cm (p=0.019) and Ki-67>2% (p=0.028) were identified as independent significant prognostic factors in multivariate analysis.\n\n\nCONCLUSIONS\nLAP represents 9% of pheochromocytoma s population and is characterized by a metastatic behavior. This study paved the way of a future pathological TNM classification.