Topical Phenytoin Versus Placebo in the Management of Acute Radiation-Induced Dermatitis in Patients with Breast Cancer: A Double-Blind Randomized Controlled Trial

Background: Acute radiodermatitis (ARD) is a common side effect of breast cancer radiotherapy. It includes erythema, burning sensation, swelling, epilation, desquamation, ulceration, or necrosis. So far, there has been no consensus about the best practice in preventing /treating ARD. Objectives: This is the first study to assess the efficacy of topical phenytoin in the prevention and treatment of ARD. Methods: This prospective randomized double-blind trial was a placebo-controlled study. A total of 70 patients with breast cancer were included. They were referred for breast radiotherapy after breast conservative surgery. Patients were randomly assigned to either the topical phenytoin or placebo group. Both ointments were applied twice and daily on affected areas of the chest. Acute radiodermatitis was evaluated every week, for 5 weeks, during radiotherapy. A blinded-to-treatment physician used the "(radiation therapy oncology group) RTOG dermatitis scoring" to do so. Results: During the first 3 weeks, ARD was neither severe (RTOG < 2) nor statistically different between the two treatment groups (P > 0.05). However, after the 3rd week, the ARD score was lower in phenytoin group than in the placebo group (P < 0.05). Conclusions: Phenytoin topical ointment could postpone the occurrence and/or decrease the severity of ARD in patients with breast cancer.