Abstract
We herein describe a male patient in his late 70s who presented with stage IV mantle cell lymphoma (MCL) and left-side-predominant pleural effusion (PE). Lymph node (LN) biopsy revealed diffuse proliferation of medium-sized cells that were positive for CD5, CD20, CD79a, BCL2, cyclin D1, and SOX11 and negative for CD3 and CD10. The cells carried t(11;14)(q13;q32)/IGH::CCND1 and the IGHV gene was minimally mutated. Lymphoma involved the systemic LNs, spleen, head of the pancreas, stomach, duodenum, and bone marrow. After one cycle of bendamustine and rituximab and one cycle of cyclophosphamide, doxorubicin, vincristine, and rituximab, surface lymphadenopathy was reduced in size; however, PE unproportionally persisted. Microscopic examination of Ziehl-Neelsen-stained smears prepared from the pleural fluid disclosed very few acid-fast bacilli, and polymerase chain reaction for Mycobacterium tuberculosis was positive. The patient was treated with rifampicin, isoniazid, pyrazinamide, and ethambutol, readily leading to resolution of PE, confirming a tuberculous origin. At five years after the initial presentation, the patient was free from relapse of both MCL and PE. Because patients with lymphoma are at high-risk of developing tuberculosis, we should note that PEs identified in lymphoma patients are not necessarily malignant effusions.
