A Case of Severe Refractory Pemphigus Vulgaris in a Patient With Stable Esophageal Malignancy

Pemphigus is a broad term that is used to describe a group of bullous autoimmune diseases affecting the skin and mucous membranes; the pathogenesis involves autoantibodies directed against various cell junction desmosomal proteins. In patients with a history of malignancy who present with bullous lesions, the differential diagnosis may include, but is not limited to, paraneoplastic pemphigus (PNP) and pemphigus vulgaris (PV) secondary to a primary autoimmune process, or induced by chemotherapy or radiation therapy. In this report, we present a case of refractory PV in a patient with stable esophageal cancer, five years after undergoing radiation therapy. He was poorly responsive to corticosteroids and intravenous immunoglobulin (IVIG). PNP or PV in a patient with stable esophageal malignancy has not been previously reported. PNP and PV can have overlapping autoantigens [desmoglein types 1 and 3 (DSG1 and DSG3)] as well as similar presentations. Thus, distinguishing between the two may be challenging in a patient with a history of cancer. More research must be done to determine if PNP can be seen in a patient with stable esophageal malignancy and, similarly, if PV can be precipitated by stable esophageal malignancy. Such research would aid in determining whether or not similar presentations are more severe or refractory to standard treatment regimens, thereby contributing to improve treatment strategies.

Follicular dendritic cell sarcoma with paraneoplatic pemphigus: Rare case and a brief review of literature

Paraneoplastic pemphigus (PNP) is often a fatal autoimmune bullous disease characterized by severe stomatitis, polymorphous skin eruptions, and underlying neoplasms. We describe a patient with PNP associated with follicular dendritic cell sarcoma (FDCS), a rare neoplasm originating from follicular dendritic cells, which are non-lymphoid, non-phagocytic accessory cells of the lymphoid system and play an integral role in regulation of the germinal center reaction and present antigens to B-cells. The presence of rich vascularity around the tumor and few hyalanized vascular follicles found in histopathological examination gives the clue that the tumor might have developed from Castleman's disease (CD). As for the mechanisms by which CD induces PNP, it has been proposed that autoantibodies secreted from the Castleman's tumor play pivotal role. This hypothesis seems to be supported by the present case, in which CD may have triggered both the FDCS and the PNP.