Surgical treatment of metachronous nonsmall cell lung cancer.

PURPOSE We report surgical results of metachronous nonsmall cell lung cancer (NSCLC). METHODS We report mortality and analyze prognostic factors for overall survival in patients with metachronous NSCLC at Nippon Medical School from July 1982 to July 2008. RESULTS Thirty-three out of 1726 patients (1.9%) who underwent lung resection had metachronous NSCLC. Mortality rate was 10%. On univariate analyses, the different histologies at the first and second operations were the only significant poor prognostic factor. Twenty-two patients (73%) had the same histology at the first and second operations: adenocarcinoma in 18 (60%) and squamous cell carcinoma in 4 (13%). Their actuarial 5- and 10-year overall survivals were both 71%, compared to 47% and 16% for patients with different histology (p = 0.0174). Sex (p = 0.1742), locations of the first and second cancers (p = 0.3957), operative procedures in patients with p-stage I at the second operation (p = 0.2782), pathological stage at the first operation (p = 0.5958), and pathological stage at the second operation (p = 0.0609) were not prognostic factors. Different histology at the first and second operations was significant based on a multivariate analysis (Hazard ratio: 3.918; p value: 0.0269; 95% confidence interval: 1.169-13.131). The actuarial 5- and 10-year overall survivals for the first cancer was 86% and 64%, compared to 65% and 45% for the second (p = 0.0609). CONCLUSIONS Our study shows that a surgical approach is beneficial for patients with metachronous NSCLC. Good prognosis in patients with the same histology may support the current criteria of metachronous NSCLC mainly based on the histology.