Mucin-producins Lung Cancer and Response to Gefitinib.

A53-year-01d woman who was hypoxemic due to primary lung adenocarcinoma with both pleuritis and pericarditis carcinomatosa was treated with gefitinib，an inhibitor of the epithelial growth factor receptor (EGFR) tyrosine kinase.The tumor seemed to produce mucin because the extremely high serum KL-6 and almost normal Sp-D values on admission.After 3 days of treatment，the patient became asymptomatic and oxygen was discontinued.The response to this drug was remarkable on chest CT findings.Mucin overproduction could offer a candidate marker to determine the patient subset displaying good responseto gefitinib