Radiation Recall Dermatitis after Bortezomib Therapy.

Introduction: Radiation recall dermatitis (RRD) is an inflammatory skin reaction at a site of previous radiation therapy after the administration of a medication, usually a chemotherapeutic agent. A radiation recall reaction has not been previously reported with bortezomib.

Case Report: A seventy-year-old man with stage III IgD multiple myeloma was treated with bortezomib after previous treatments with pulse decadron and cyclophosphamide. The patient was treated ten years earlier for a chest wall sarcoma with a local resection and radiation therapy to the tumor bed. After receiving bortezomib therapy for multiple myeloma, the patient developed erythema, desquamation, and ulceration only at the site of radiation therapy ten years prior. The patient received a dose reduced second infusion, causing a similar reaction.

Discussion: RRD is an inflammatory skin reaction that develops in a previously irradiated area after administration of certain promoting agents, most often with chemotherapy. Unlike radiation enhancement, there may be a long interval between the eruption and the administration of the causative agent. A number of drugs have been associated with this phenomenon, particularly the anthracyclines. Bortezomib has not been previously described as a causative agent for RRD. Erythema is the most common sign, which may be painful. Vesiculation, desquamation, and ulceration have also been reported. Histologically, the involved areas reveal epidermal dysplasia, necrotic keratinocytes, mixed inflammatory reaction, and sometimes psoriasiform dermatitis. Dose reduction, and the use of corticosteroids have been used to prevent recurrence of RRD, although rechallenge with the same agent may not lead to RRD again. The pathogenesis of this local phenomenon is not well understood, although an idiosyncratic drug hypersensitivity reaction has been proposed.