The combination of gemcitabine and cisplatin is one of the most active chemotherapy regimens against non-small cell lung cancer (NSCLC). This study was designed to evaluate the efficacy and safety of gemcitabine combined with cisplatin in a 3-week cycle regimen for patients with operable, early stage NSCLC. Gemcitabine at a dose of 1000 mg/m(2) on days 1 and 8 of each 21-day cycle for 3 cycles, followed by cisplatin at a dose of 75 mg/m(2) on day 1 was administered to patients with previously untreated, operable, early stage (IB-IIIA) NSCLC. A total of 47 patients (46 male, mean age 56.0+/-8.0 years) who met the eligibility criteria were enrolled. The pathological complete response rate was 5.3% of operated patients and 4.3% of total patients. At visit 4, 57.1% of the patients had partial response, 38.1%, stable disease and 4.8%, progressive disease. The main toxicities - leukopenia, neutropenia and thrombocytopenia - were usually clinically asymptomatic and did not require hospitalization. Non-hematological toxicities were minimal and manageable. Disease free and 12-month overall survival rates were over 70% and 80%, respectively. This study demonstrates that the administration of gemcitabine and cisplatin combination for 3 cycles is effective and tolerable for patients with operable, early stage NSCLC. Low toxicity profile and promising survival outcome suggest that this regimen has an encouraging activity in this subset of patients.