Malignant minor pleural effusion detected on thoracotomy for patients with non–small cell lung cancer: is tumor resection beneficial for prognosis?

Background. This study attempts to clarify the benefit of surgery for non–small cell lung cancer (NSCLC) with malignant minor pleural effusion that is detected at thoracotomy. Methods. Records of surgical patients with NSCLC were reviewed, with a definition of minor pleural effusion as less than 300 mL. The patients were divided into three groups as follows: (1) group C consisted of patients who underwent grossly complete resection; group I, patients with incomplete tumor resection; and group E, patients who underwent exploratory thoracotomy only. Results. There were 196 patients who had minor pleural effusion; of these, 96 (46%) underwent an examination to define the malignancy status of pleural effusion after surgery. In 43 patients (45%), the effusion was found to be malignant. The median survival time and 5-year survival rate, respectively, were 13 months and 9% for group C (n = 11); 34 months and 10% for group I (n = 14; p = 0.3); and 17 months and 0% for group E (n = 18; p = 0.8). Conclusions. Tumor resection is not beneficial for the survival of patients with NSCLC who have a minor malignant pleural effusion.