Risk Factors of Recurrence in Patients With Clinical Stage IA Adenocarcinoma Presented as Ground-Glass Nodule.

BACKGROUND: In this study we aimed to identify the risk factors of recurrence in patients with clinical stage IA adenocarcinoma presented as ground glass nodule (GGN) on computed tomography scans.

PATIENTS AND METHODS: The study included 245 patients with clinical stage IA adenocarcinoma presented as GGN who underwent surgery during 2010 to 2013. All patients were divided into 2 subgroups on the basis of consolidation diameter to tumor diameter (C/T) ratio on lung window: (1) ground-glass opacity (GGO)-dominant subgroup (C/T ≤ 0.5; n = 179); (2) solid-dominant subgroup (C/T > 0.5; n = 66). Recurrence-free survival (RFS) was analyzed to identify independent risk factors of recurrence using the Kaplan-Meier approach and multivariable Cox models.

RESULTS: Patients in the GGO-dominant subgroup had a better prognosis than those in the solid-dominant subgroup (5-year RFS: 98% vs. 87%; P < .001). Multivariate analysis confirmed that C/T ratio was an independent risk factor for RFS in patients with clinical stage IA adenocarcinoma presented as GGN (hazard ratio [HR], 9.47; 95% confidence interval [CI], 1.75-51.1; P = .009). In the analysis of the solid-dominant group, multivariate analysis showed that limited resection was an independent risk factor of recurrence in this subgroup (HR, 6.86; 95% CI, 1.50-31.42; P = .013). Regarding the GGO-dominant subgroup, surgical type was not a risk factor of recurrence.

CONCLUSION: Patients with clinical stage IA solid-dominant adenocarcinoma (C/T ratio > 0.5) had a higher rate of recurrence after limited resection than lobectomy. Thus, limited resection should be performed cautiously in these patients (C/T ratio > 0.5).