How should we manage small focal pure ground-glass opacity nodules on high-resolution computed tomography? A single institute experience

•33 of 89 patients with p-GGO on HRCT underwent surgical resection.•41 of 47 resected p-GGO nodules was adenocarcinoma.•The rate of invasive adenocarcinoma was significantly higher when the tumor size became larger.•The indication or timing of intervention for p-GGO nodules should be carefully considered.

BackgroundAlthough the detection of pure ground-glass opacity (p-GGO) nodules on high-resolution chest computed tomography (HRCT) often implies a diagnosis of lung adenocarcinoma, the management of p-GGO nodules remains under discussion.ObjectiveTo assess the correlation between the radiological and pathological diagnoses of small p-GGO on HRCT.Patients and methodsThis is a single-institution retrospective study. We analyzed 89 consecutive patients, including 33 patients with resected p-GGO nodule(s) equal or less than 20 mm in maximal diameter on axial images of HRCT.ResultsThirty-nine patients underwent locoregional treatment (Treatment group), including surgical resection in 33 and stereotactic body radiation therapy in six. The remaining 50 patients were observed (Observation group) using periodic chest HRCT. The median follow-up time was 30.4 (4.9–102.5) months in the Treatment group and 44.8 (0.4–1125.8) months in the Observation group. During the follow-up period, the p-GGO nodules increased in size in eight patients over a median of 20.6 (12.1–50.6) months, with increased attenuation in three patients over a median of 20.6 (12.1–50.6) months, and either decreased in size or disappeared in four patients over a median of 6.9 (2.0–11.2) months. Thirty-three patients with 47 nodules underwent surgical resection, including 41 adenocarcinomas, one neuroendocrine tumor, three cases of atypical adenomatous hyperplasia and two benign lesions. The frequency of invasive adenocarcinoma was higher among the larger p-GGO nodules.ConclusionsCareful observation and decision making with respect to the timing of intervention in cases of p-GGO nodules are warranted.