Primary extranodal natural killer/T-cell lymphoma of bronchus and lung: A case report and review of literature

Abstract

Primary pulmonary non-Hodgkin's lymphoma (NHL) is very rare. It represents less than 1% of all NHL, and 0.5-1% of all primary pulmonary malignancies. Almost all cases of primary pulmonary NHL originate from B-cell lineage. We present a case of a 53-year-old man with primary extranodal NK/T-cell lymphoma of the bronchus and lung, presented progressive dyspnea caused by right lower lung consolidation, and pleural effusion. Initial chest computed tomography suggested advanced lung cancer. Bronchofiberscopy showed a polypoid tumor on which a biopsy was performed. Histologically, the diffusely infiltrative atypical cells were positive for cytoplasmic CD3, CD56, granzyme B, and negative for cytokeratin, CD20 immunostains, suggesting NK/T cell lineages. In situ hybridization for Epstein-Barr virus encoded ribonucleic acid (EBER) was positive. Herein, we discuss the clinicopathological features of this case and review the literature on primary extranodal NK/T-cell lymphoma of the lung. Compared with other patients, who died after the first cycle of chemotherapy and/or within three months, our patient had longer survival under aggressive chemotherapy and auto-peripheral blood stem cell transplantation.

Keywords: Lymphoma; lung and/or bronchus; natural killer/T‐cell.

Figure 1

(a) Chest radiograph showed lung consolidation over the right lower lung field with moderate pleural effusion. (b) Chest computed tomography revealed a tumor in the right main bronchus (arrow) and right lower lobe of the lung, with mediastinum and adjacent organ involvement. (c) Bronchofiberscopy showed a polypoid tumor with whitish tissue coating and erosion over the orifice of the right main bronchus. (d) Easy bleeding of the tumor after bronchofiberscopic biopsy.

Figure 2

(a) Tissue showed extensive necrosis (hematoxylin & eosin [H&E] stain, magnification, 100x). (b) The diffusely infiltrative small to medium‐sized tumor cells had irregular nuclear contours, condensed chromatin, inconspicuous nucleoli, and pale cytoplasm. Mitotic figures were easily found, including atypical form (arrow) (H&E 400x). (c) By immunohistochemistry, the tumor cells were positive for cytoplasmic CD3ε (400x). (d) Positive for CD56 (400x). (e) Positive for granzyme B (400x). (f) In situ hybridization for Epstein‐Barr virus encoded ribonucleic acid was positive (400x).