P1.05-059 Factors Associated with Recurrence and Survival in Patients with Curatively Resected Stage IA Adenocarcinoma of the Lung

Abstract

Even when meticulously clinically and pathologically studied, completely resected stage IA adenocarcinoma of the lung does recur. However, there are few data regarding the patterns of recurrences and their risk factors in this population. Therefore, this study characterizes cancer recurrence and its risks and assesses recurrence-free survival in patients with curatively resected stage IA adenocarcinoma. Between January 1990 and December 2005, a total of 214 patients were given a final diagnosis of pathologic stage IA (UICC-7) adenocarcinoma of the lung. The medical records of these patients were retrospectively reviewed with regard to patient characteristics, tumor pathologic findings and follow up status. Survival was analyzed by the Kaplan-Meier method, log-rank test, and Cox proportional hazards analysis. The median follow up after curative resection was 83 months. Cancer recurred in 28 patients (13%). Among them, local recurrence occurred in 10 patients (5%), whereas distant recurrence occurred in18 patients (8%). Recurrence earlier and later than 5 years after surgery was in 15 patients (7%) and in 13 patients (6%), respectively, with nearly constant risk. At 5 years after index resection, 175 patients (82%) were alive without evidence of cancer recurrence, 11 patients (8%) had experienced recurrence of cancer but still alive and 11 patients (5%) had died with non-cancer causes. Recurrence-free 5- and 10-year survival rates were 92.5 and 70.0%, respectively. Univariate analysis revealed five significant prognostic factors: gender (p=0.0177); lepidic component (p =0.0007); tumor location (p=0.0099); pleural invasion (p=0.0274) and lymphatic or vascular vessel invasion (LVI) (p< 0.0001). Multivariate analysis revealed lepidic component, tumor location, and LVI as significant factors. Hazard ratios for recurrence were 0.381 for having lepidic component (95% CI, 0.147-0.979; p= 0.0451), 0.361 for right sided tumor (95% CI, 0.188-0.692; p= 0.0022), and 2.785 for having LVI (95% CI, 1.392-5.555; p= 0.0038). Surgically “cured” stage IA adenocarcinoma of the lung recurs. Our analyses indicate no-lepidic component, tumor location, LVI as an independent indicator for cancer recurrence. Identifying high-risk patients for recurrence will simplify decision making for postoperative treatment strategies.