Objectives: Cisplatin remains the pivotal chemotherapy in squamous cell carcinoma of the head and neck (SCCHN), with nephrotoxicity considered the dose-limiting toxicity. The purpose of our study was to propose an outpatient high-dose cisplatin protocol aimed at preventing nephrotoxicity and to analyze the results of its utilization in patients with SCCHN treated with concurrent radiotherapy.
Materials and methods: We retrospectively evaluated 82 SCCHN patients treated with outpatient high-dose cisplatin concurrent with radiotherapy at our institution. Acute kidney injury (AKI) and chronic kidney disease were defined by Kidney Disease Improving Global Outcomes criteria. Associated factors were identified using analysis of covariance models for categorical variables and adjusted Pearson correlations for continuous variables.
Results: The incidence of AKI during treatment was 34.2%. With a median follow-up of 25.7 months, the average decrease in estimated glomerular filtration rate was 12.57 mL/min/1.73 m (SD=18.58). At 1 year and at last follow-up, 5.4% and 4.4% of patients had estimated glomerular filtration rate <60 mL/min/1.73 m. Predictors associated with AKI and chronic kidney disease were: lower baseline weight and creatinine, higher baseline creatinine clearance, smoking, female sex, African American race, hypertension, and increased hydration and magnesium replacement requirements.
Conclusions: We encountered limited early and late nephrotoxicity. Importantly, nephrotoxicity was not the main dose-limiting toxicity. Our results emphasize the importance of close monitoring and additional replacement of water and electrolytes as needed. A consistent method of measuring and reporting chemotherapy-induced nephrotoxicity would be a valuable contribution to the literature.