Pathological prognostic factors of recurrence in early stage lung adenocarcinoma

Histological heterogeneity is thought to be important for prognosis of lung adenocarcinoma. We investigated to determine pathological features with prognostic value for recurrence of early stage lung cancer.

A total of 368 patients who underwent curative surgical resection for early stage lung adenocarcinoma between 2009 and 2012 were enrolled. Pathologic characteristics including the presence of visceral pleural invasion, micropapillary patterns, aerogenous spread, lymphovascular invasion, perineural invasion and necrosis were examined. The correlations between pathological factors and clinical outcomes were analysed to determine prognostic significance.

Mean follow-up was 43.0 months (±14.56, ranging from 0.0 to 73.9 months). Three-year overall survival was 95.2% and disease-free survival was 89.8%. The recurrence rate was 9.0% (33 patients) and the mortality rate was 6.0% (22 patients). The presence of a micropapillary pattern (P < 0.002), lymphatic invasion (P < 0.000), aerogenous spread (P < 0.000), vascular invasion (P = 0.036) and necrosis (P < 0.000) were negative prognostic factors of recurrence in univariate analysis. In multivariate analysis, only aerogenous spread had prognostic value (P = 0.020). The recurrence hazard ratio for the presence of aerogenous spread was 3.2 (95% confidence interval 1.20-8.47).

The presence of aerogenous spread was an independent pathological risk factor of recurrence in stage I lung adenocarcinoma. Micropapillary pattern had prognostic importance for recurrence in univariate analysis, but not in multivariate analysis.