Objectives: Curative resection is not indicated for non-small cell lung cancer (NSCLC) with pleural seeding, which is classified as stage IV (M1a) disease. However, some patients with a presumably resectable main tumor are diagnosed with localized pleural seeding during surgery.
Methods: A retrospective analysis was performed of 3,975 patients who underwent surgery for NSCLC from 2000 to 2011. Among these cases, 78 (2.0%) patients had unexpected pleural seeding detected during surgery. Exploration with pleural biopsy was performed in 42 of these patients (exploration-only group) and pulmonary resection, including for the main tumor, was performed in 36 cases (resection group; sublobar resection in 12, lobectomy in 21, and pneumonectomy in 3 patients). Survival and cancer progression rates were estimated using the Kaplan-Meier method. Cox proportional hazard regression was used to evaluate prognostic factors associated with survival.
Results: Adenocarcinoma was the predominant histological type in both the exploration and resection groups (88.1 and 86.1%, respectively). Epidermal growth factor receptor expression was detected in 22 (52.4%) patients of the exploration group and 21 (58.3%) patients of the resection group. Baseline characteristics including age, sex, comorbidity, pulmonary function, and clinical T/N status were not significantly different between the two groups. There were no postoperative deaths in either group but postoperative complications occurred in two (4.8%) patients of the exploration group and three (8.3%) patients of the resection group. The overall 3- and 5-year survival rates in the exploration group were 41.1 and 15.2%, respectively, with a median survival time (MST) of 33 months, whereas they were 66.7 and 42.7%, respectively, in the resection group, with a 52-month MST (p = 0.012). Local and regional progression-free rates were significantly different (p < 0.001 and p = 0.029, respectively) between groups, whereas no difference was seen in the distant metastasis rates (p = 0.957). In multivariate survival analysis, surgical resection was the only significant prognostic factor (p = 0.01).
Conclusions: Pulmonary resection including the main tumor, regardless of resection extent, may increase long-term survival for NSCLC patients with localized pleural seeding first detected during surgery, without a significant increase in hospital mortality or morbidity.
Georg Thieme Verlag KG Stuttgart ยท New York.