Clinical characteristics and work-up of small to intermediate-sized pulmonary nodules in a Chinese dedicated cancer hospital

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.