Paraneoplastic pemphigus: A retrospective case series in a referral center in northern Taiwan

Background/Objectives Paraneoplastic pemphigus (PNP) is a rare mucocutaneous disease with a high mortality rate. It is defined by polymorphic mucocutaneous manifestations, particular histological features, characteristic results of direct and indirect immunofluorescence examinations, presences of specific autoantibodies, and associations with underlying neoplasms. However, currently, there is no existing study regarding the characteristics of PNP patients in Taiwan. In this study, we report a case series and try to determine the specific presentations of PNP patients in Taiwan. Materials and methods PNP patients treated in a referral center in northern Taiwan from 1998 to 2012 were retrospectively recruited. The clinical manifestations, histopathological features, findings of direct and indirect immunofluorescence, results of immunoblotting, and all relevant clinical information were collected. Results Eleven patients were identified with an average age of 62 years. Polymorphic mucocutaneous manifestations were observed in almost all patients. The most common presentation was pemphigus-like lesions, followed by lichen planus-like lesions. All patients had recalcitrant oral mucosal lesions. Five and four patients had genital and eye involvements, respectively. The mostly associated neoplasm is Castleman's disease, followed by malignant thymoma. Acantholysis is the mostly observed histological features, followed by lichenoid dermatitis and interface dermatitis. Depositions of immunoglobulins or complements on the surface of keratinocytes or along basement membrane zone were found in eight and seven patients, respectively. Respiratory symptoms presented in eight patients. Despite intensive treatments, seven patients expired. Conclusion PNP in Taiwanese patients has a high association with Castleman's disease or malignant thymoma. Complete laboratory examinations and thorough investigations for occult neoplasms are mandatory to establish a diagnosis in patients with clinical suspicions of PNP. ? 2013, Taiwanese Dermatological Association. Published by Elsevier Taiwan LLC. All rights reserved.