Purpose: To compare compliance with and efficacy of intravenous (IV) and subcutaneous (SC) amifostine for the treatment of patients undergoing radiotherapy for head and neck cancer.
Patients and methods: Patients with newly diagnosed squamous cell carcinoma of the head and neck, who were eligible for radiotherapy and who were not receiving concurrent chemotherapy, were randomly assigned to receive either IV amifostine (200 mg/m(2) daily for 3 minutes, 15 to 30 minutes before irradiation) or SC amifostine (500 mg; two sites; 20 to 60 minutes before irradiation). The primary end point was late xerostomia at 1 year as indicated by unstimulated and stimulated salivary flow rates, a patient benefit questionnaire score, and Radiation Therapy Oncology Group (RTOG) late toxicity grade.
Results: Results for IV (n = 143) versus SC (n = 148) administration were as follows. There was no significant difference in compliance (69% for IV v 71% for SC) in patients receiving a full dose of amifostine. Reasons for dose reduction were acute toxicity (25% for IV v 27% for SC; P = .51) and logistics (18% for IV v 9% for SC administration; P = .09). Acute toxicity differed significantly in terms of grade 1 to 2 hypotension (19% for IV v 8% for SC; P = .01), grade 1 to 2 skin rash (9% for IV v 21% for SC; P = .01), and local pain (0% for IV v 8% for SC; P = .003). The incidence of grade 2 or greater xerostomia was significantly higher for patients who received amifostine via SC administration (37% for IV v 62% for SC; P = .005) in the 127 patients (n = 67, IV; n = 60, SC) evaluable at 1 year but not at 2 or 3 years (36% for IV v 51% for SC administration; P = .19; 32% for IV v 41% for SC; P = .63). A generalized linear mixed-model analysis of all data revealed no significant difference in patient self-assessment of salivary function (P = .25), unstimulated or stimulated salivary flow rates (P = .054 and .82, respectively), or grade 2 or greater xerostomia (P = .23).
Conclusion: SC amifostine administration was not significantly superior to IV amifostine administration in terms of patient compliance or efficacy.