Gefitinib as a first-line therapy of advanced or metastatic adenocarcinoma of the lung in never-smokers.

Abstract

A subset of patients with adenocarcinoma of the lung who had never smoked cigarettes showed excellent tumor responses to gefitinib therapy. To evaluate the efficacy of gefitinib as a first-line therapy in this subgroup of patients, we conducted a phase II study. Eligible patients had no smoking history, stage IIIB or IV adenocarcinoma, Eastern Cooperative Oncology Group performance status 0 to 2, and adequate organ functions. Treatment consisted of daily oral administration ofF 250 mg gefitinib for 28 days until disease progression. Responses were assessed after every two cycles of therapy. Of 37 patients enrolled, 36 were assessed for response. Twenty-five patients (69%) had partial response, 4 (11%) had stable disease, and 7 (19%) had progressive disease. Of 10 patients with evaluable brain metastases, 7 had objective responses in both intracranial and extracranial lesions, 1 had stable disease in the brain and dramatic response in the extracranial lesions, and 2 had progressive disease in both sites. After a median follow-up of 48 weeks (range, 4-70 weeks), 26 patients had disease progression, with median progression-free survival of 33 weeks, and 9 patients died, all due to disease progression. The median survival time has not been reached yet but the estimated 1-year survival rate was 73%. Common toxicities were skin rash and mild diarrhea but there was no significant hematologic toxicity. Gefitinib showed very dramatic antitumor activity, even in the brain, with unprecedented survival outcome in never-smoker adenocarcinoma patients. These data support the use of gefitinib as a first-line therapy in this particular subgroup.