Continuous administration of EGFR-TKIs following radiotherapy after disease progression in bone lesions for non-small cell lung cancer.

BACKGROUND There have been reports suggesting that continuous administration of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is advantageous for patients in which disease progression was observed after the establishment of clinical benefit from EGFR-TKIs. We retrospectively evaluated the clinical course of patients who received continuous administration of EGFR-TKIs after disease progression was detected solely in bone lesions. PATIENTS AND METHODS The medical records of patients administered gefitinib or erlotinib between 2002 and 2010 were reviewed. We evaluated the progression-free survival (PFS) and overall survival (OS) in patients who had bone metastases after the establishment of clinical benefit from EGFR-TKI and who received radiation therapy for the bone lesion and continuous treatment with EGFR-TKI. RESULTS Ten patients were enrolled in this study. The median PFS and OS were 88 days and 330 days, respectively. Furthermore, a longer duration from the start of first EGFR-TKI to detection of bone metastases (p=0.0049) was identified as being significantly associated with a longer PFS. CONCLUSION Our data suggest that continuous administration of EGFR-TKI is a treatment option for patients with bone metastases who previously benefited from therapy with EGFR-TKI.