Lichenoid Dermatitis After Hypofractionated Radiation Therapy for Breast Cance

Lichenoid dermatitis is a rare complication after radiation therapy and is often considered as a delayed hypersensitivity reaction. It is different from lichen planus and is characterized by fine white scale (Wickham’s striae). Here, we report a case of lichenoid dermatitis developed after hypofractionated whole-breast radiation therapy followed by breast-conserving surgery. A 60-year-old female patient underwent hypofractionated whole-breast radiation therapy followed by a boost to the tumor bed. Post-radiation course was uneventful, but violaceous, polyangular, and pruritic papules accompanied by the eruption were noted at the boost site. Clinical findings were consistent with lichenoid dermatitis, so steroid ointment and oral antihistamines were administered. Her lichenoid dermatitis was completely relieved in 2 weeks, and there was no sign of relapse during the 5 years follow-up. There are some reports of lichen planus induced after radiotherapy; however, this is the first report that shows lichenoid dermatitis as a possible complication after hypofractionated radiation therapy for breast cancer.