Efficacy and safety of granulocyte macrophage-colony stimulating factor (GM-CSF) on the frequency and severity of radiation mucositis in patients with head and neck carcinoma

Abstract

Based on the clinical evidence of mucosal protection by GM-CSF during cytotoxic chemotherapy, a pilot study was undertaken to determine the safety and mucosal reaction of patients receiving GM-CSF while undergoing definitive conventional fractionated radiotherapy in head and neck carcinoma. Patients were considered eligible if buccal mucosa and oropharynx were included in the teleradiation field. Ten adult patients with squamous cell carcinoma of head and neck (buccal mucosa--8 and posterior 1/3 tongue--2) were entered into the trial. Radiation therapy was delivered with telecobalt machine at conventional 2 Gy fraction and 5 fractions/week. The radiation portals consisted of two parallel opposing lateral fields. GM-CSF was given subcutaneously at a dose of 1 microg/kg body weight, daily, after 20 Gy until the completion of radiation therapy. Patients were evaluated daily for mucosal reaction, pain, and functional impairment. The median radiation dose was 66 Gy. Eight patients received > or = 60 Gy. The tolerance to GM-CSF was good. All 10 patients completed the planned daily dose of GM-CSF without interruption. Mucosal toxicity was Grade I in four patients till the completion of radiotherapy (dose range 50-66 Gy). Six patients developed Grade II reaction, fibrinous mucosal lesions of maximum size 1.0-1.5 cm, during radiotherapy. None developed Grade III mucositis. The maximum mucosal pain was Grade I during GM-CSF therapy. In two patients after starting GM-CSF the pain reduced in intensity. Functional impairment was mild to moderate. All patients were able to maintain adequate oral intake during the treatment period. Total regression of mucosal reaction occured within 8 days following completion of radiotherapy. GM-CSF administration concurrently with conventional fractionated radiotherapy was feasible without significant toxicity. The acute side effects of radiotherapy namely mucositis, pain, and functional impairment were nil to minimal. The results are suggestive of mucosal protection by GM-CSF during radiotherapy and warrants further study in randomized double blind trial.