Nutritional Consequences of Radiotherapy in Nasopharynx Cancer Patients

Abstract

Abstract: 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 (T₀), end-RT (T₁), 2 mo post-end-RT (T₂), and 6 mo post-end-RT (T₃). The BMI at end-RT was 21.5 ± 3.7 kg/m² (range = 13.7-27.9 kg/m²) and was significantly lower than that at pre-RT (P < 0.001). Body weight at T₁-T₃ was significantly lower than that at T₀ (P < 0.001). Mean percentage weight loss was 10.8% at end-RT. Fifty-five percent of patients (20 of 30) had ≥10% 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 T₂ and T₃ were significantly lower than that at T₀ (P < 0.01). Patients' calorie intake generally declined from T₀ to T₁ (from 1,857 P < 411 kcal to 11,68 ± 549 kcal, P < 0.001) and then increased from T₁ to T₃. The calorie intakes at T₂ and T₃ were not significantly different from that at T₀ but were significantly higher than that at T₁. 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.