Primary pulmonary diffuse large B-cell lymphoma

Authors


  • Conflict of interest: Nothing to report.

A 67-year-old woman, nonsmoker, complained of dyspnoea and weakness accompanied by weight loss of 2 months duration. She suffered from mild asthma for ∼10 years. The patient underwent radiological evaluation including chest radiographs and computed tomography (CT) of chest. CT scans showed bilateral, interstitial pulmonary involvement. Open thoracotomy with wedge resection of intralobar pulmonary was done.

A histopathological examination of pulmonary specimen revealed proliferation of large cells, which pressed the alveolar epithelium and created “pseudofollicular” pattern. In immunohistochemical staining, large cells were CD20, BCL-6—positive and BCL-2, CD10, IRF4/MUM1, CD3, CKA1/A3—negative. MIB1/Ki67 was expressed in about 70% of the nuclei (Image 1 A–D). Diffuse large B-cell lymphoma (DLBCL), nongerminal center B-cell like (non GCB) was diagnosed. On clinical examination, no palpable lymph nodes and no hepatosplenomegaly was found. Serum lactate dehydrogenase (LDH) was 521 U/l (normal value: 100–248). No evidence of extrathoracic disease by clinical staging work-up was confirmed. That includes CT scans of abdomen, pelvis, and bone marrow biopsy. Positron emission tomography–computed tomography (PET/CT) scan was positive in bilateral pulmonary tissues. Maximum standarized uptake value (SUV max) amounted from 8.1 to9.2 (Images 2 and 3). The patient was treated with R-CHOP regimen. She received six cycles and attained complete remission (CR) by negative PET scan with SUV max from 1.1 to 1.3 (Image 4). 1234

Illustration 1.

Morphological and immunohistochemical features of pulmonary lesion. Proliferation of large cells in the airless lung parenchyma (H&E, ×200) (A), the large cells expressing CD20 (B), and showing immunoreactivity for MIB1/Ki67 in about 70% of cells (EnVision stain, ×200) (C), neoplastic cells pressing the alveolar epithelium (CKA1/Amath image) (D). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

Illustration 2.

Chest CT at diagnosis.

Illustration 3.

PET/CT of the lung at diagnosis. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

Illustration 4.

PET/CT of the lung after completion of chemotherapy. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

Primary pulmonary non Hodgkin's lymphoma (NHL) is very rare and accounts 0.4% of all lymphomas. The most common primary pulmonary lymphoma is mucosa-associated lymphoid tissue type (MALT) lymphoma, which represents 70–90% of all primary pulmonary NHL [1–3]. Diffuse large B cell lymphoma occurs only in 10% cases of primary pulmonary NHL [4]. In some cases, transformation from MALT lymphoma to DLBCL may occur. Most of the patients with primary pulmonary NHL have no clinical symptoms. In symptomatic cases, common presentation of primary pulmonary NHL includes systemic symptoms or respiratory symptoms such as dyspnoea. The treatment of primary pulmonary lymphomas is not clearly established [3, 4]. Therapeutic approach should be based on biological features such as histology, stage and performance status. Risk factors for primary pulmonary NHL have not been definited. International Extranodal Lymphoma Study Group proposed some statistically significant adverse prognostic factors such as: Ann Arbor stage IV, increased LDH, extranodal involvement, international prognostic index, intermediate/high risk, or high risk. Therapeutic options in primary NHL of the lung include the following strategies: watch and wait approach, surgery, chemotherapy, and chemotherapy followed by radiotherapy [4–6]. Anthracyclines-based chemotherapy with anti-CD20 monoclonal antibody seems to be optimal therapeutic strategy in patients with primary DLBCL of the lung. Despite negative prognostic factors (non-GCB, primary extranodal DLBCL, and increased LDH) our patient up-to-date remains in CR.

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