Metabolic abnormalities associated with wt loss during chemo-RT of HN cancer

Abstract

5554 Purpose/Objective: Concurrent chemo-irradiation (chemo-RT) of head and neck (HN) cancer often leads to significant wt loss due to acute mucositis and dysphagia. We studied the metabolic consequences of wt loss during chemo-RT. Materials/Methods: 96 pts with locally advanced HN cancer were treated from 1995–2001 with 1–3 courses of induction cisplatin/5-FU followed with RT (70 Gy over 7 wks) concurrent with cisplatin (100 mg/m2 q3wks) (chemo-RT). Primary sites included larynx (48 pts), oropharynx (40 pts), hypopharynx (3 pts), and oral cavity (5 pts). Stages were III (38 pts) and IV (58 pts). Baseline wt, creatinine clearance, and metabolic laboratory evaluation was obtained prior to initiation of induction chemo and prior to chemo-RT. During the course of chemo-RT, weekly weights and laboratory evaluation were measured. Results: During induction chemo 2% of pts had >10% body wt loss and significant changes were found in BUN (p=0.04), BUN:creatinine ratio (p=0.03), HCO3- (p=0.01), Mg2+ (p=0.004), and albumin (p=0.001). There were no significant changes in wt (p=0.19), creatinine (p=0.93), K+ (p=0.79) or Na+ (p=0.43). During chemo-RT significant increases in BUN, creatinine, BUN: creatinine ratio, and HCO3- as well as significant decreases in wt, Mg2+, albumin, K+ and Na+ (all with p<0.0001) were observed. These changes were all significantly greater than those observed during induction chemo (p=0.001). During chemo-RT, 35% patients had >10% body wt loss. 5% had an increase in creatinine of more than x2 pre-chemo-RT values, all had a wt loss of >10%. There was a significant correlation between % body wt loss and % creatinine and BUN rise during the course of chemo-RT (R=0.40, p<0.0001). Conclusions: Significantly more metabolic alterations were observed during chemo-RT compared with induction chemo, including worsening of kidney function, which was significantly correlated with wt loss. While these findings do not establish a cause-effect relationship, they emphasize the importance of aggressive supportive measures of hydration and nutrition during chemo-RT. No significant financial relationships to disclose.