Surgical Treatment for Metachronous Lung Cancers

Abstract

Objective. Surgical treatment for metachronous lung cancers should be determined based on curability as well as residual pulmonary function. We reviewed the clinicopathological background, surgical procedure, and corresponding prognoses of patients with metachronous lung cancers. Patients. Of 815 consecutive patients who underwent pulmonary resection for primary lung cancer between April 1994 and December 2005, 22 patients (2.7%) were found to have metachronous lung cancers. Results. The first primary cancer was p-stage IA in 11 patients, p-stage IB in 5, p-stage IIB in 1, p-stage IIIA in 4, and p-stage IV in 1. The second primary cancer was p-stage IA in 14 patients, p-stage IB in 3, p-stage IIB in 2, p-stage IIIA in 1, and p-stage IIIB in 2. Average maximal tumor diameter of the first primary cancer (31.8 mm; 12-77 mm) was greater than that of the second primary cancer (19.3 mm; 5-50 mm) with statistical significance (p=0.001). The surgical procedures for the first primary cancer were lobectomy or more extensive resection in all patients, while those for the second primary cancer were limited operation in 15 patients in order to retain residual pulmonary function. The 5-year survival rate after the second resection was 63.9%. When patients were classified into 2 groups by the pathological stage of the second primary cancer, the 5-year survival rate of patients with a second primary cancer of p-stage IA (92.9%) was greater than that of patients with the second primary cancer of p-stage IB or more advanced diseases (0%), with a significance level of p<0.001. Conclusion. Patients with the second primary cancer of p-stage IA can have a favorable outcome even when they have metachronous lung cancers. Thus we conclude that careful follow up should be continued after the first pulmonary resection, and moreover an aggressive surgical treatment is recommended as long as their performance status or residual pulmonary function allows.