OUTLINE: This is a randomized, double-blind, placebo-controlled, multicenter study. Patients are stratified according to primary cancer (lung vs gastrointestinal vs other), severity of weight loss in the past 2 months (less than 10 pounds vs 10 pounds or more), planned concurrent chemotherapy (yes vs no), age (under 50 vs 50 and over), and prognosis (good vs bad vs unsure). Patients are randomized to 1 of 3 treatment arms.