MEASUREMENTS OF RESTING ENERGY-EXPENDITURE AND BODY-COMPOSITION BEFORE AND AFTER TREATMENT OF SMALL-CELL LUNG-CANCER

Background: Many patients with small cell lung cancer are reported to lose weight, but the mechanism of this effect is unclear. Patients and methods: Measurements of resting energy expenditure (REE), using indi rect calorimetry and body composition (fat, fat-free mass and organ ma ss), using dual energy X-ray absorptiometry (DXA) and abdominal CT sca ns were measured in 38 patients with newly-diagnosed small cell lung c ancer. Twenty-eight patients were restudied at the end of treatment. R esults: In those who responded to treatment there was no change in bod y weight, but a decrease in REE of 15.7+/-11.7 kJ/kg fat free mass/day , whilst in the non-responders body weight decreased by 4.33+/-5.4 kg, but REE was unchanged.Conclusions: This study provides evidence for t umour-induced hypermetabolism which is independent of changes in gross body composition, although the absolute increase is small, approximat ely 0.8 MJ/day. However since body weight was maintained in those pati ents who responded to treatment either total energy expenditure was de creased, implying decreases in physical activity, or energy intake was increased.