P-208 Pancreatic neuroendocrine neoplasia: Experience of a comprehensive cancer center

Abstract

Pancreatic neuroendocrine neoplasia (Pan-NEN) are rare tumors in which therapeutic options have been increasing over the last decade. However, the effect of implementing these therapies in the real world is poorly understood. We aim to characterize the clinical features and therapeutic strategies of patients with Pan-NEN within a 12-year period in a cohort of patients followed at IPOFG-Porto. We performed a retrospective cohort study of patients diagnosed with Pan-NEN between 2006 and 2017 at the largest NEN reference Portuguese Center. Progression-free (PFS) and overall survival (OS) time estimates were calculated by Kaplan-Meier method. To assess the impact of baseline clinicopathological characteristics on survival, we used univariate and multivariate Cox proportional hazard models. Ninety-seven patients were included. Mean patient age was 59.5±13.55 years-old, with 55 (56.7%) being male. Forty-five patients (48.5%) had an Adjusted Charlson Comorbidity Index >3. Most patients were symptomatic at diagnosis, mainly due to tumor location-related symptoms (n=55, 69.6%), and 12 (15.0%) hormone secretion-related symptoms. Most tumors were well differentiated neuroendocrine tumors (NET) (n=77, 79.9%) according with WHO 2010 classification. NET G1 and NET G2 constituted the majority of cases (n=72, 75.8%). Predominant pancreatic topography was body and tail (n=43, 44.3%) followed by head (n=28, 28.9%). Fifty-two (53.6%) had localized/locoregional disease while 46.4% (n=45) had metastatic disease. Liver was the most frequent site of synchronous metastasis at diagnosis (n=42, 93.3%), followed by non-regional nodal (n=11, 24.4%) and bone (n=11, 24.4%). Globally, 60 (61.9%) surgical procedures were performed, 22 (22.9%) transarterial embolization, 5 (5.2%) other locoregional therapies, 56 (57.7%) somatostatin analogues, 23 (23.7%) Peptide Receptor Radionuclide Therapy, 11 (11.3%) everolimus and 32 (33.0%) chemotherapy. Forty-six patients (47.4%) had potentially curative disease, of which 43 (93.5%) had surgery as primary treatment. Eighteen patients (45.0%) had disease recurrence after surgery. Five-year Disease-free Survival was 61.9%. Seventy-two patients received antineoplastic palliative treatments (51 patients with metastatic/irresectable disease at diagnosis, 18 with disease recurrence and 3 refused curative intention therapy). Of those, twenty-six (36.1%) received 2 lines and 20 (27.8%) ≥3 lines of treatment. Median PFS after first line treatment was 25.0 months (95%CI 18.0-32.0) and median OS was 58 months (95%CI 30.0-86.0). Patients with localized/locoregional disease had a median OS of 160 months and patients with metastatic disease of 29 months, HR 4.55 (95%CI 2.58-8.02), p On univariate analysis, the risk of death was increased in those patients with NEC, metastatic disease at diagnosis, and primary location of the tumor not in the pancreatic body or tail. On multivariate analysis, NEC (HR 2.46 95%CI 1.28-4.73) and metastatic disease (HR 3.44 95%CI 1.85-6.37) were independent prognostic factors. Patients with PAN-NENs analyzed in this study present similar characteristics to other cohorts described in the literature. Therapeutic strategies in PAN-NENs are highly diversified and adapted to histological differentiation, stage, hormone hypersecretory-related symptoms and patients characteristics and preferences. NEC and metastatic disease were associated with a significant increase risk of death.