Malignant pleural effusion from lung adenocarcinoma treated by gefitinib.

Small molecule inhibitors targeting epidermal growth factor receptor (EGFR) are known to be active against non-small cell lung cancer (NSCLC) although the pharmacodynamics of these agents on malignant pleural effusion (MPE) remains unclear. Here we describe a case of lung adenocarcinoma with massive MPE treated successfully by gefitinib and chest drainage. Using sequential MPE samples before and during gefitinib therapy, the morphological changes and apoptosis of cancer cells were analyzed. Apoptosis of cancer cells was detected as early as 4 hours on, but not before, gefitinib therapy, suggesting that the pharmacodynamic assessment of such molecular targeting agents might be feasible for MPE.