Pemphigus vulgaris and internal malignancy

Five patients with pemphigus vulgaris representing 12% of the total cases seen at the University of California at Los Angeles Center for the Health Sciences were found to have associated internal malignancies. Three patients developed internal malignancy after receiving corticosteroid therapy for periods of 2–108 months. In approximately 54% of patients surveyed in the literature with this association, the malignancy involved the lymphoid or reticuloendothelial systems. Pemphigus and internal malignancies or thymomas may be related through some intervening variables such as immunosuppressive therapy, the antigenic and cross‐reacting nature of the primary tumor, or as an immunologic consequence of associated autoimmune disease, which occurred in 48% of the cases reviewed. Our observation of five patients with pemphigus and internal malignancies greatly exceeds chance expectations for the Los Angeles area. A review of the literature indicates that pemphigus and internal malignancies are causally related by the criteria employed by Curth.