Primary lung intravascular large B-Cell lymphoma clinically mimicking sarcoidosis: A rare case report and review of literature.

We present a case of a 73-year-old male who initially presented with night sweats, intermittent fever, worsening dry cough and shortness of breath. CT scans revealed atelectasis and calcified mediastinal lymphadenopathy, raising a suspicion for sarcoidosis. Multiple lung biopsies were performed. Microscopically, atypical lymphocytes were identified within capillaries, small arteries and veins. These lymphocytes were large with prominent nucleoli. Immunohistochemical staining demonstrated tumor cells positive for CD20, CD79a, Pax-5, CD10 and Mum-1, while negative for CD3, cytokeratin, S100, and CD34. LDH serum level was increased (480 IU/L). Extra pulmonary lymphoma was not detected elsewhere in the patient. These findings support the diagnosis of primary lung intravascular large B cell lymphoma (IVLBCL). Literature review of 52 cases demonstrated occurrence of primary lung IVBCL in patients between the ages (35-85) with a slight male predominance (1.167:1). The most common clinical presentation was fever associated with dyspnea.