Atypical Presentation of Classical Hodgkin Lymphoma as Superior Vena Cava Syndrome With Paraneoplastic Eosinophilia and Rash: A Case Report

A 47-year-old female presented with progressive left-sided facial swelling, exertional dyspnea, and a generalized pruritic rash. Physical examination revealed significant facial edema, cervical lymphadenopathy, and a diffuse maculopapular eruption. Laboratory evaluation demonstrated an absolute eosinophil count of 1.81 x 109/L. Cross-sectional imaging with a computed tomography (CT) scan identified a large anterior mediastinal mass invading the superior vena cava (SVC) and left brachiocephalic vein, supporting the diagnosis of SVC syndrome. Histopathologic evaluation of an ultrasound-guided core cervical lymph node biopsy confirmed classical Hodgkin lymphoma (cHL), nodular sclerosis subtype. This case highlights an uncommon initial presentation of cHL characterized by the convergence of SVC syndrome, eosinophilia, and a paraneoplastic pruritic rash in the absence of classic B symptoms. Prompt identification of these atypical manifestations must be reconciled with the broader clinical context to avoid delays in diagnosis and treatment. Furthermore, this case emphasizes the necessity of obtaining a definitive tissue diagnosis before initiating corticosteroid therapy, which can mask lymphoproliferative architecture and obscure pathologic findings.