Objectives:To evaluate the characteristics and work-up of small to intermediate-sized pulmonary nodules in a Chinese dedicated cancer hospital.Methods:Patients with pulmonary nodules 4-25 mm in diameter detected via computed tomography (CT) in 2013 were consecutively included.The analysis was restricted to patients with a histological nodule diagnosis or a 2-year follow-up period without nodule growth confirming benign disease.Patient information was collected from hospital records.Results:Among the 314 nodules examined in 299 patients,212 (67.5％) nodules in 206 (68.9％) patients were malignant.Compared to benign nodules,malignant nodules were larger (18.0 mm vs.12.5 mm,P ＜ 0.001),more often partly solid (16.0％ vs.4.7％,P ＜ 0.001) and more often spiculated (72.2％ vs.41.2％,P ＜ 0.001),with higher density in contrast-enhanced CT (67.0 HU vs.57.5 HU,P =0.015).Final diagnosis was based on surgery in 232 out of 314 (73.9％) nodules,166 of which were identified as malignant [30 (18.1％) stage Ⅲ or Ⅳ] and 66 as benign.In 36 nodules (11.5％),diagnosis was confirmed by biopsy and the remainder verified based on stability of nodule size at follow-up imaging (n =46,14.6％).Among 65 nodules subjected to gene (EGFR) mutation analyses,28 (43.1％) cases (EGFR19 n =13;EGFR21 n =15) were identified as EGFR mutant and 37 (56.9％) as EGFR wild-type.Prior to surgery,the majority of patients [n =194 (83.6％)] received a contrast-enhanced CT scan for staging of both malignant [n =140 (84.3％)] and benign [n =54 (81.8％)] nodules.Usage of positron emission tomography (PET)-CT was relatively uncommon [n =38 (16.4％)].Conclusions:CT-derived nodule assessment assists in diagnosis of small to intermediate-sized malignant pulmonary nodules.Currently,contrast-enhanced CT is commonly used as the sole diagnostic confirmation technique for pre-surgical staging,often resulting in surgery for late-stage disease and unnecessary surgery in cases of benign nodules.