Radiation recall reaction to idarubicin resulting in vaginal necrosis

Radiation recall reactions are uncommon delayed tissue reactions seen in previously irradiated sites following treatment with cytotoxic agents. We evaluated a 64-year-old who developed two episodes of acute vulvitis and vaginal necrosis after receiving idarubicin therapy for acute myelogenous leukemia. Three years earlier she had undergone successful radiotherapeutic treatment of a stage I squamous cell carcinoma of the vagina. Her symptoms and examination findings resolved with local therapy and discontinuation of idarubicin. Recall reactions have been associated with the antitumor antibiotics actinomycin D and doxorubicin and, more recently, the mitotic inhibitors vinblastine and Taxol. The mechanism of this phenomenon is poorly understood but may be related to sequential stem cell injury or depletion. Because physical and biopsy findings are nonspecific, the diagnosis must be suspected on the basis of the patient's history and the location of the reaction within the prior treatment field.