Peer Review #1 of "Clinicopathological characteristics and prognosis of pulmonary large cell neuroendocrine carcinoma aged ≥65 years (v0.2)"

Abstract

Objective: The present study was designed to better characterize the clinicopathological features and prognosis in patients aged ≥ 65 years with pulmonary LCNEC. Methods: Eligible patients with pulmonary LCNEC were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database between January 2004 and December 2013. The primary endpoints included cancer specific survival (CSS) and overall survival (OS). Results: Data of 1,619 eligible patients with pulmonary LCNEC were collected. These patients were subsequently categorized into two groups: 890 patients in the older group (age 65 years), and 729 in the younger group (age < 65 years). More patients were of white ethnicity, stage I, married, and with tumor size ˂5 cm in the older group in comparison to the younger group. However, there were a significantly lower proportion of patients undergoing surgery, chemotherapy and radiotherapy in the older group. The 5-year CSS rates of the younger group and older group were 23.94% and 17.94% (P =0.00031), respectively, and the 5-year OS rates were 20.51% and 13.47% (P ˂ 0.0001), respectively. Multivariate analyses indicated that older age