Elderly patients are more vulnerable to toxicity from chemotherapy. Activating epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer (NSCLC) are associated with enhanced response to EGFR tyrosine-kinase inhibitors. We studied patients with advanced NSCLC for whom treatment was customized based on EGFR mutation status.
We screened 57 chemotherapy-naïve patients with histologically or cytologically confirmed NSCLC, stage IIIB or IV, aged 70years or older, and with an Eastern Cooperative Oncology Group performance status 0 or 1, for EGFR exon 19 codon 746–750 deletion and exon 21 L858R mutation. Twenty-two patients with EGFR mutations received gefitinib; 32 patients without mutations received vinorelbine or gemcitabine. The primary endpoint was the response rate.
The response rate was 45.5% (95% confidence interval [CI]: 24.4%, 67.8%) in patients with EGFR mutations and 18.8% (95% CI: 7.2%, 36.4%) in patients without EGFR mutations. The median overall survival was 27.9months (95%CI: 24.4months, undeterminable months) in patients with EGFR mutations and 14.9months (95%CI: 11.0months, 22.4months) in patients without EGFR mutations. In the gefitinib group, grade 3/4 hepatic dysfunction and dermatitis occurred in 23% and 5% of patients, respectively. In patients treated with vinorelbine or gemcitabine, the most common grade 3 or 4 adverse events were neutropenia (47%; four had febrile neutropenia), anemia (13%), and anorexia (9%). No treatment-related deaths occurred.
Treatment customization based on EGFR mutation status deserves consideration, particularly for elderly patients who often cannot receive second-line chemotherapy due to poor organ function or comorbidities.
This trial is registered at University hospital Medical Information Network-clinical trial registration (http://www.umin.ac.jp/ctr/index/htm) with the registration identification number C000000436.