Metabolic abnormalities associated with weight loss during chemoirradiation of head-and-neck cancer

Purpose: Weight loss caused by acute mucositis and dysphagia is common during concurrent chemoirradiation (chemo-RT) of head-and-neck (HN) cancer. The metabolic consequences of weight loss during chemo-RT were investigated. Patients and Methods: Ninety-six patients with locally advanced HN cancer were treated from 1995 to 2001 on protocols that consisted of 1 to 2 cycles of induction cisplatin/5-fluorouracil followed by irradiation (70 Gy over 7 weeks) concurrent with cisplatin (100 mg/m² every 3 weeks). Body weights and metabolic evaluations were obtained before and during induction chemotherapy and chemo-RT. Greatest percent changes in weight and in the laboratory values were calculated for each phase of therapy. Results: During induction chemotherapy, significant changes were found in BUN, BUN:creatinine ratio, HCO₃, Mg, and albumin, but not in creatinine, Na, K, or weight. During chemo-RT, significant additional changes were observed in all parameters measured, including increases in BUN, creatinine, BUN: creatinine ratio, and HCO₃ and decreases in Mg, albumin, Na, K, and weight. The magnitude of most of these changes was significantly greater during chemo-RT than during induction chemotherapy. During chemo-RT, 35% of the patients had more than 10% body weight loss and 6 patients had an increase in creatinine of more than 100%, including 5 patients with Grade 2 nephrotoxicity, all of whom had weight loss 10% or more. Significant correlations were found between weight loss and creatinine (p < 0.0001) or BUN (p = 0.0002) rises, but not with BUN:creatinine ratio or other metabolic changes. Age, gender, tobacco history, hypertension, and diabetes mellitus were not significant predictors of nephrotoxicity. Conclusions: Weight loss during cisplatin-containing chemo-RT was found to be associated with reduced kidney function. These findings do not establish cause-effect relationships; however, they highlight the importance of intensive supportive measures of nutrition and hydration beyond standard hydration during cisplatin administration. These intensive measures should be enacted before a 10% weight loss is reached.