Follicular dendritic cell sarcoma with paraneoplatic pemphigus: Rare case and a brief review of literature
A 20-year-old boy presented with 7 months history of multiple polymorphous vesiculobullous mucocutaneous eruptions around the lips and subsequently in buccal mucosa causing dysphagia. He later developed conjuntivitis associated with blurred vision and atypical targetoid lesions with crusts surrounded by erythema scattered on the trunk and extremities including prepuce and perianal region []. He lost 5 kg during this period. Direct immunoflorescence of biopsy specimen from Skin lesion showed deposition of Immunoglobulin G (+) and C3 in the intercellular region of epidermal cells mainly in the suprabasal region. Linear deposition of IgG is also seen in dermo-epidermal junction suggestive of PNP. Computed tomography (CT) scan revealed a well defined intensely enhancing mass lesion with central necrosis in the right hemipelvis, 6 cm in size, abutting the right obturator internus muscle and displacing the urinary bladder anteriorly. Engorged vessels were seen around the mass []. Exploratory laprotomy was done but the mass was found to be unresectable. Histopathlogy of the mass showed oval to spindle cells in a background of vascular stroma infiltrated by lymphocytes. The cells were immunopsitive for CD21, CD35, CD23, S-100, Claustrin, CD34, CD31, S-100; Leucocyte common antigen, and H uman leukocyte antigen-DR were also positive in some cells. Hyaline-vascular follicles were identified at the peripheral portion or occasionally scattered in the center of the tumor. Rich vascularity was highlighted by the CD34 immunostaining [Figures and ]. Overall features favoured FDCS. The presence of rich vascularity around the tumor and few hyalanized vascular follicles found in histopathological examination (HPE) gave the clue that the tumor might have developed from CD. He tested negative for human immunodeficiency virus. He was started on systemic steroids. His truncal lesions marginally improved after steroids but there was no improvement in arm lesions. He was then given Rituximab, cyclophosphamide, Adriamycin, vincristin, prednisolone. He expired post 1st course of chemotherapy due to pseudomonas infection.