45 yr old presents with a 2.8 cm right upper lobe mass. He has a 20 year history of smoking two packs of cigarettes a day. Physical exam is unremarkable.
CT of the chest reveals ipsilateral mediastinal lymphadenopathy and a moderate right pleural effusion. PET scan shows activity in the right upper lung mass and the ipsilateral mediastinal lymph nodes.
MRI of the brain with gad is unremarkable. PFTs reveal an FEV1 of 2.1 liters. During the course of his evaluation, thoracentesis is done on three occasions for symptomatic pleural effusion. Cytology shows reactive mesothelial cells. The ratio of pleural fluid LDH and protein to serum values is less than 0.5.