Purpose: There is as yet no optimal treatment regimen for patients with epidermal growth factor receptor (EGFR) gene wild-type non-small-cell lung cancer (NSCLC) that has progressed despite cytotoxic chemotherapy. This trial was performed to evaluate the efficacy and toxicity of erlotinib, a tyrosine kinase inhibitor of EGFR, in Japanese patients with EGFR wild-type tumors.
Methods: Patients with stage III/IV or postoperative recurrence of NSCLC whose tumors have wild-type EGFR were eligible. Erlotinib (150 mg/day) was administered until disease progression or unacceptable toxicity occurred. The primary end point was disease control rate (DCR).
Results: Thirty-one patients (23 men and 8 women; median age, 71 years; range, 31-89) were enrolled between January 2008 and June 2011. Twenty-one had adenocarcinoma, nine had squamous cell carcinoma, and one had large cell carcinoma. Ten, nine, eight, and four patients showed performance status 0, 1, 2, and 3, respectively. Erlotinib was administered following the median 3.1 regimens of cytotoxic chemotherapies. One patient achieved complete response, four showed partial response, and eight had stable disease. Thus, response rate was 17.2%, and DCR was 44.8%. Skin rash was the most common side effect (80.6%). Two patients developed interstitial lung disease. Nevertheless, all of these events were reversible, and there were no treatment-related deaths. The median progression-free survival and survival times were 2.1 and 7.7 months, respectively.
Conclusion: Erlotinib might be an alternative option for patients resistant to cytotoxic chemotherapy even in those with EGFR wild-type NSCLC.