ARM I: Patients receive gemcitabine hydrochloride intravenously (IV) over 30 minutes on days 1 and 8, cisplatin IV, and placebo IV over 30-90 minutes on day 1. Treatment repeats every 21 days for 6 courses in the absence of disease progression or unacceptable toxicity. Patients then receive placebo IV over 30-90 minutes every 21 days in the absence of disease progression or unacceptable toxicity.