Forty patients with stage IIIB or IV NSCLC were randomized to receive either a biweekly regimen of GC [ gemcitabine ( 1,000 mg/m ( 2 ) on days 1 and 14 ) and carboplatin ( area under the concentration-time curve , AUC = 3 on days 1 and 14 ) ] every 28 days or a standard regimen of GC [ gemcitabine ( 1,000 mg/m ( 2 ) on days 1 and 8 ) and carboplatin ( AUC = 5 on day 1 ) ] every 21 days .