Based on early clinical evidence of potential mucosal protection by granulocyte-macrophage colony stimulating factor (GM-CSF), the Radiation Therapy Oncology Group conducted a double-blind, placebo-controlled, randomized study to test the efficacy and safety of GM-CSF in reducing the severity and duration of mucosal injury and pain (mucositis) associated with curative radiotherapy (RT) in head-and-neck cancer patients.
Eligible patients included those with head-and-neck cancer with radiation ports encompassing >50% of oral cavity and/or oropharynx. Standard RT ports were used to cover the primary tumor and regional lymphatics at risk in standard fractionation to 60-70 Gy. Concurrent cisplatin chemotherapy was allowed. Patients were randomized to receive subcutaneous injection of GM-CSF 250 microg/m2 or placebo 3 times a week. Mucosal reaction was assessed during the course of RT using the National Cancer Institute Common Toxicity Criteria and the protocol-specific scoring system.
Between October 2000 and September 2002, 130 patients from 36 institutions were accrued. Nine patients (7%) were excluded from the analysis, 3 as a result of drug unavailability. More than 80% of the patients participated in the quality-of-life endpoint of this study. The GM-CSF did not cause any increase in toxicity compared with placebo. There was no statistically significant difference in the average mean mucositis score in the GM-CSF and placebo arms by a t test (p = 0.4006).
This placebo-controlled, randomized study demonstrated no significant effect of GM-CSF given concurrently compared with placebo in reducing the severity or duration of RT-induced mucositis in patients undergoing definitive RT for head-and-neck cancer.