Radiation-Induced Pemphigus or Pemphigoid Disease in 3 Patients With Distinct Underlying Malignancies
The cutaneous lesions of radiation-induced pemphigus or pemphigoid disease may resemble other skin diseases, including recurrent underlying cancer. We performed a computerized search of Mayo Clinic (Rochester, Minnesota) archives and identified 3 cases of pemphigus or pemphigoid disease that occurred after radiation therapy for breast, cervical, and metastatic malignancies, respectively. In 2 of these patients, the disease was initially confined to the irradiated field but subsequently disseminated to other parts of the patients’ bodies, including mucosal surfaces. In all 3 patients, the blistering disease occurred 5 to 14 months after the onset of radiation therapy. All 3 were treated with corticosteroids and demonstrated complete recovery of the skin eruption after radiotherapy was discontinued. Although the precise mechanism of this cutaneous eruption is unknown, clinicians should be alert for this potentially serious complication and evaluate all cutaneous eruptions developing during and after radiotherapy.
Practice Points
- The use of radiation therapy is increasing because of its therapeutic benefit, especially in advanced-stage cancer patients.
- Although there is a wide range of adverse effects associated with radiation therapy, pemphigus or pemphigoid disease is rare and needs to be distinguished from other skin diseases or even recurrent underlying cancer.
- The precise mechanism of radiation-induced pemphigus or pemphigoid disease is unknown, but clinicians should be alert to this potentially serious complication, and all cutaneous eruptions developing during and after radiation therapy should be evaluated with routine histologic examination in conjunction with direct immunofluorescence, serum for indirect immunofluorescence, and enzyme-linked immunosorbent assay.
In summary, radiation-induced pemphigus or pemphigoid disease, a rare but serious adverse effect of radiation therapy, should be considered in patients with new-onset blistering or erosive skin disease who have recently undergone irradiation. The accurate diagnosis of pemphigus or pemphigoid disease is important because such diseases often require long-term immunosuppressive therapy. A thorough history and skin examination must be obtained from all patients who receive radiation therapy and subsequently have blisters or eruptions on the skin, mucous membranes, or both. Appropriate diagnostic studies, including routine biopsy for histologic evaluation and direct immunofluorescence, serum for indirect immunofluorescence, and enzyme-linked immunosorbent assay, should be performed to exclude pemphigus or pemphigoid disease.
