EP1.12-30 Clinicopathological Features and Survival of Lung Neuroendocrine Tumors

Lung neuroendocrine tumors (NETs) are a heterogenous group of malignances classified into four histological types, being small cell lung cancer (SCLC) the most frequent and mortal. Due to the rarity of the disease, limited clinical data is available for NTEs. Herein we aim to describe the epidemiology, clinical features and survival of this group of neoplasms. This is a retrospective analysis of patients diagnosed with lung NETs between 2010 and 2014 at Instituto Nacional de Enfermedades Neoplasicas (INEN) in Lima, Peru. Demographic characteristics, possible predisposing factors, histological type and stage were collected from clinical files. Survival analysis was calculated with Kaplan-Meier method. Prognostic factors were analyzed with Cox regression method. We identified 69 patients with lung NETs, which corresponds to the 2.8% of lung cancers diagnosed in the same time period. Median age at diagnosis was 62 years and 59.4% of patients were male. Possible risk factors described were smoking history (50%) and familiar history of cancer (23.2%). Mean time from onset of symptoms to diagnosis was 3 months. Frequent symptoms at diagnosis were cough (75%), chest pain (59%), dyspnea (50%), weight loss (49%), hemoptysis (28%), hyponatremia (19.6%) and superior vena cava syndrome (13.8%). Between NETs, SCLC was the most common histological type (82.8%), followed by typical carcinoid (12.1%) and large cell neuroendocrine carcinoma (5.2%). Almost all patients (91.8%) had unresectable disease at diagnosis (21.3%, stage III; 70.5% stage IV) according TNM classification. Among SCLC, 60.4% had an extensive disease according to the IASLC classification, with extra thoracic compromise in bone (25.6%), brain (23.1%), suprarenal gland (21.1%) and liver (15.8%). The preferred systemic treatment was cisplatin/etoposide (93%) in the metastatic setting. The median overall survival for all histological types was 6.7 months (range 4.1 – 9.2) (Differences by histological grade in Table 1). Among clinical factors, weight loss at diagnosis emerged as a prognostic factor associated with survival of high-grade NETs (HR 3, 95% CI 1.6 – 5.5).Tabled 1IIIIIIIVmOSCarcinoids40%0%30%30%87m (40.4 – 133.6)High-grade NETs8.8%0%21.1%70.2%4.5m (2.6 – 6.4) Open table in a new tab Lung NETs have a heterogenous clinical presentation with unresectable disease at diagnosis in almost all cases. SCLC is the most frequent histology, however, this proportion regarding of the total cases of primary lung neoplasms is markedly lower than what is reported in the literature, probably to our lower frequency of smokers. The survival of this group of patients is poor in comparison to other series being weight loss at diagnosis an important prognostic factor in this series.