Pulmonary Endothelial Impairment During Gefitinib Therapy: A Preliminary Assessment with Iodine-123-Metaiodobenzylguanidine (123IMIBG) Scintigraphy

Iodine-123-metaiodobenzylguanidine ( 123 I-MIBG) kinetics in the lung could serve as a novel diagnostic tool to evaluate endothelial damage. Interstitial lung disease (ILD) associated with gefitinib, an epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), has been reported as a serious adverse effect. This study was performed to examine the possibility that gefitinib induces pulmonary endothelial damage. Serial 123 I-MIBG scintigraphy was performed in 5 patients with non-small cell lung cancer before and one month after initiation of gefitinib treatment. Anterior planar images were acquired 15 min after injection of 123 I-MIBG and the total lung to upper mediastinum ratio (L/M) was calculated in both lungs. None of the patients developed ILD during the study. There were no significant differences in the values of L/M before and after gefitinib therapy. These findings suggest that gefitinib has little influence on the pulmonary endothelium in patients with no signs of ILD.