Differentiating pre- and minimally invasive from invasive adenocarcinoma using CT-features in persistent pulmonary part-solid nodules in Caucasian patients

• We analyzed CT-features of part-solid ground glass nodules in Caucasians.
• These CT-features were compared to pathology on full resection specimen.
• Several CT-features can help differentiating invasive adenocarcinoma.
• A solid component larger than 5 mm had 100% sensitivity for invasive adenocarcinoma.

ObjectiveTo retrospectively investigate the diagnostic value of pre-operative CT-features between pre/minimally invasive and invasive lesions in part-solid persistent pulmonary ground glass nodules in a Caucasian population.Materials and methodsRetrospective review of two pre-operative CTs for 31 nodules in 30 patients. There were 10 adenocarcinomas in situ, 1 minimally invasive adenocarcinoma, 20 invasive adenocarcinomas. We analyzed the correlation between histopathology and the following CT-features: maximal axial diameter, maximal orthogonal axial diameter, height, density, size of solid component, air bronchogram, pleural retraction, nodule mass, disappearance rate and their evolution during follow-up.ResultsIn univariate analysis, invasive adenocarcinomas had a higher maximal height, density, solid component size, mass, a lower disappearance rate and presented more often with pleural retraction (p < 0.05). After logistic regression performed with the uncorrelated parameters using a method of selection of variables, only the size of solid component remained significant, with 100% sensitivity for invasive adenocarcinoma when larger than 5 mm.ConclusionPreoperative CT-features can help differentiating in situ and minimally invasive adenocarcinomas from invasive adenocarcinomas in Caucasian patients. A solid component larger than 5 mm in diameter had 100% sensitivity for the diagnosis of invasive adenocarcinoma.