Prognostic factors for stage I lung adenocarcinoma and surgical management of subsolid nodules

This study aims to identify the prognostic factors for stage I lung adenocarcinoma and to evaluate the surgical management of subsolid nodules.

The study included 133 patients (90 males, 43 females; mean age 64.9 years; range, 29 to 82 years) who had undergone operation in our clinic for stage I lung adenocarcinoma between January 2007 and December 2015. Clinical, radiological and pathological data were retrospectively evaluated and their effects on recurrence and survival were examined by Kaplan-Meier and Cox regression analyses.

Comparing the histopathological tumor types according to the pathological tumors size, we determined that the prevalence of invasive adenocarcinoma significantly increased with increasing tumor size (p<0.001). For all nodules, a tumor disappearance rate lower than 25% negatively influenced disease-free survival and a maximum standardized uptake value higher than 5.6 negatively influenced overall survival (p=0.027 for both). The grouping, which was performed considering the maximum standardized uptake value 5.6 as the cut-off value, was an independent prognostic factor for overall survival (hazard ratio: 5.973, 95% confidence interval: 1.186-30.073, p=0.03). Five-year overall survival rate was statistically significantly higher in patients who underwent wedge resection or segmentectomy for subsolid nodules compared to those who underwent lobectomy (100% vs. 79.3%, p=0.044).

Sublobar resections can be safely performed in subsolid nodules smaller than 2 cm in diameter with tumor disappearance rate ≥25% and maximum standardized uptake value ≤5.6.