Gefitinib Improves Bronchorrhea from Mucinous Bronchioloalveolar Carcinoma and Serum Surfactant Protein-D Levels is a Novel Surrogate Predictor of Treatment Benefit

Abstract

Background. Mucinous bronchioloalveolar carcinoma (BAC) with goblet cell features causes bronchorrhea and pneumonia-like consolidation, and does not produce surfactant protein (SP). This subtype of lung cancer is known to harbor K-ras mutations, resulting in resistance to treatment with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib. Case. However, we report a case in which gefitinib improved bronchorrhea from mucinous BAC with high serum SP-D levels. The tumor cells had an EGFR mutation, and did not show the features of goblet cells. Conclusion. Mucinous BAC is heterogeneous, and high serum SP-D levels may be a useful marker of treatment benefit with gefitinib.