Outcomes of gefitinib therapy for disease recurrence in medically inoperable stage I lung adenocarcinoma patients with active EGFR mutations receiving stereotactic body radiotherapy: a single-institute retrospective study

Abstract

Introduction: Anticancer therapy for disease recurrence in medically inoperable stage I lung adenocarcinoma patients receiving stereotactic body radiotherapy (SBRT) has not been previously reported. Gefitinib is tolerable and effective in patients with active epidermal growth factor receptor (EGFR) mutations who have an advanced age and/or a low performance status, but whether gefitinib improves the survival of such patients with disease recurrence after SBRT remains unclear. Patients and methods: We retrospectively evaluated overall survival after disease recurrence in patients with active EGFR mutations who received gefitinib (GEF group) and patients without active EGFR mutations who did not receive gefitinib (non-GEF group). Results: During a follow-up period with a median time of 36.0 months, disease recurrence occurred in 10 of 20 patients with medically inoperable stage I lung adenocarcinoma who received SBRT (2 cases with local tumor recurrence alone and 8 cases with lymph node and/or distant metastasis). The median age or the median Charlson comorbidity index score were 84 years and 2 in the GEF group (n=4) and 81 years and 2 in the non-GEF group (n=6), respectively. Two cases in the GEF group received chemotherapy after first-line gefitinib therapy. Two cases in the non-GEF group received chemotherapy, but the others received best supportive care alone. The median overall survival time from disease recurrence was significantly different between the 2 groups (27.3 vs. 3.6\u2009mo, P=0.038). Two cases with grade 2 radiation pneumonitis did not have a recurrence of pneumonitis during gefitinib therapy. Conclusions: Gefitinib might be useful as a salvage therapy in patients who desire to continue anticancer treatment.