A recent retrospective analysis mentioned that 23% of Non-Small Cell Lung Cancer (NSCLC) patients those who acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) demonstrated ‘disease flare’ after discontinuation of EGFR-TKI. However, two thirds of patients enrolled in the analysis were treated with EGFR-TKI in the adjuvant setting, maintenance therapy, or combined with cytotoxic chemotherapy.Methods
To clarify the details of disease flare in the metastatic NSCLC, we reviewed the clinical records of EGFR mutated, advanced adenocarcinoma patients who were treated with gefitinib monotherapy in our hospital between January 2007 and December 2010. Disease flare was defined as unexpected interventions (e.g. radiation therapy, or pleural drainage), hospitalization, or death attributable to disease progression after gefitinib discontinuation.Results
Five of 63 patients (8%; 95% CI: 3–17%) experienced disease flare. The flare group demonstrated shorter median progression-free survival with gefitinib than no flare group (231 versus 328 days, P < 0.01). Patients with pleural involvement at the time of disease progression tended to have disease flare. Among the flare group, the median survival time after gefitinib discontinuation was 97 days (73–123 days). Nineteen of 63 patients continued gefitinib beyond radiological progression, and none of them experienced disease flare.Conclusion
Our analysis demonstrated a lower incidence of disease flare after gefitinib discontinuation compared with the previous report. Clinical factors associated with disease flare were almost similar to that.