A patient with stage IV malignant melanoma treated with daily radiotherapy and low-dose (100 mg/m2) daily gemcitabine developed a blistering skin eruption, fever and neutropenia consistent with overlap Stevens–Johnson syndrome/toxic epidermal necrolysis (SJS/TEN). The diagnosis was confirmed by skin biopsy of an affected area. The case history is described, and the literature relating to the development of SJS/TEN in association with chemotherapy and radiotherapy administration is reviewed. This report describes a serious potential complication of concurrent gemcitabine and radiotherapy.