Testicular Plasmacytoma as the First Manifestation of Systemic Multiple Myeloma

Multiple myeloma is a hematological malignancy characterized by clonal proliferation of plasma cells, usually confined to the bone marrow. Extramedullary disease (EMD) occurs in 7-18% of patients during the disease course and is associated with poor prognosis. Among extramedullary sites, testicular involvement is extremely rare, with an incidence of less than 2%. We present a rare case of testicular plasmacytoma as the first manifestation of systemic multiple myeloma, highlighting its imaging features and clinical implications.