A Case of Mucous Membrane Pemphigoid Complicated by Malignant Lymphoma

Abstract

Mucosal pemphigus occurring in a background of malignant lymphoma is rare. The patient was a 68-year-old woman who presented with the chief complaints of oral pain and mucosal erosions, and a skin biopsy and blood tests were performed. Serology for anti-BP180, anti-Dsg1, and anti-Dsg3 antibodies was negative. Direct fluorescence testing revealed no IgG deposition, while indirect fluorescence testing revealed anti-basement membrane antibodies. Serology was positive for full-length BP180 ELISA and BP180-C-terminal, based on which we made the diagnosis of mucosal pemphigoid. CT showed a mediastinal tumor and pleural effusion. Pleurocentesis was performed, and a cell block was prepared. Based on the results of cytological examination, we made the diagnosis of diffuse large B-cell lymphoma. The patient was initiated on R-CHOP therapy, which resulted in improvement of the mucocutaneous eruption. She died in a hospice 18 months after the start of treatment. This patient presented as a case of mucosal pemphigoid associated with DLBCL. Mucosal pemphigus is relatively rarely associated with malignant diseases other than solid tumors. Autoimmune bullous disease would be initially suspected in patients presenting with oral mucocutaneous eruption. In addition, malignant tumors can also be associated with autoimmune blistering, and a systematic search should be performed.