Nasopharynx cancer (NPC) occurs frequently in southern China. Radiotherapy (RT) is the standard treatment for this cancer and weight loss is commonly observed during and for a prolonged period after RT The determinants of this phenomenon are not well known. The nutritional status of 38 NPC patients was assessed serially before and for a 6-mo period after RT Body weight, body composition (by dual X-ray absorptiometry), basal metabolic rate (BMR, by indirect calorimetry), and calorie intake (by 3-day dietary record) were documented at pre-RT (To), end-RT (T-1), 2 mo post-end-RT (T-2), and 6 mo post-end-RT (T-3). The BMI at end-RT was 21.5 +/- 3.7 kg/m(2) (range = 13.7-27.9 kg/m(2)) and was significantly lower than that at pre-RT (P < 0.001). Body weight at T-1-T-3 was significantly lower than that at T-0 (P < 0.001). Mean percentage weight loss was 10.8% at end-RT Fifty-five percent of patients (20 of 30) had greater than or equal to10% weight loss by the end of RT BMR corrected for body weight did not change significantly among the four time points, but BMRs corrected for lean body mass at T-2 and T-3 were significantly lower than that at T-0 (P < 0.01). Patients' calorie intake generally declined from To to T, (from 1,857 +/- 411 kcal to 11,68 +/- 549 kcal, P < 0.001) and then increased from T-1 to T-3. The calorie intakes at T-2 and T-3 were not significantly different from that at To but were significantly higher than that at T-1. Patients were in negative energy balance before, during, and up until 6 mo after RT The recovery in body weight lagged behind the recovery of dietary intake. Eighty-two percent of NPC patients had significant weight loss and was in negative energy balance at the end of RT which persisted for at least 6 mo. This finding suggests that there is room for improvement in the nutritional status of patients with NPC treated with RT.
