Influence of Ground Glass Opacity and the Corresponding Pathological Findings on Survival in Patients with Clinical Stage I Non-Small Cell Lung Cancer.

Introduction: The aim was to clarify the influence on patient prognosis of ground glass opacity (GGO) component in each new TNM stage and propose grouping reflecting the prognosis more accurately.

Methods: We examined the data on 1290 patients who underwent lung cancer resection from 2003 to 2011. The demographics and overall survival of patients with adenocarcinoma with and without GGO, squamous cell carcinoma, and the others were compared according to clinical stage from 0 to IB. In adenocarcinoma, we examined the distribution of histological subtypes of adenocarcinoma with and without GGO in each clinical stage.

Results: Each clinical stage differentiated overall survival well. However, the prognosis of the patients with adenocarcinoma with GGO was considerably more favorable than that of the others in clinical stage IA2 and IA3 but not of those in clinical stage IB. In clinical stage 0 to IA3, patients showing adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive lepidic predominant adenocarcinoma accounted for about 50% of the total number of patients with adenocarcinoma with GGO (stage 0, 16 of 21; stage IA1, 113 of 143; stage IA2, 80 of 157; and stage IA3, 45 of 94). In clinical stage IB, 20% of adenocarcinomas with GGO showed invasive solid predominant adenocarcinoma (IB, seven of 38). Most of the adenocarcinomas without GGO were in clinical stage IA2 to IB, and the distribution of histological subtypes was similar at each clinical stage. Invasive acinar and solid predominant adenocarcinomas were more common in adenocarcinoma without GGO.

Conclusions: Clinical T classification considering GGO component may offer more accurate prognosis for patients with lung cancer less than 3 cm in invasive diameter.