Primary pulmonary extranodal NK/T-cell lymphoma: a case report and literature review.

Extranodal natural killer/T-cell lymphoma (ENKTL) is rare lymphoma subtype with a very poor prognosis. ENKTL in the lung is strongly associated with Epstein-Barr virus (EBV) and is extremely rare; only a few cases have been reported. In the present study, we report a case that a 40-year-old male who presented with cough, sputum and intermittent fever for one month. Chest radiograph revealed progressive multiple nodules in both lungs with ground-glass opacities and bilateral pleural effusion. Based on clinical characteristics and computed tomography (CT) findings, he was initially treated with empirical antibiotics. As there was no significant improvement, bone marrow puncture, left axillary mass biopsy and CT- guided percutaneous lung biopsy were conducted. Therefore, a diagnosis of primary pulmonary ENKTL was confirmed by pathology as cells are positive for CD2, cytoplasmic CD3e, CD56. In situ hybridization for EBV-encoded ribonucleic acid (EBER) was positive. Next generation sequencing (NGS) was used to determine potential therapeutic targets, and the missense mutation of signal transducer and activator of transcription 3 (STAT3) was found. However, the patient demonstrated rapid deterioration and refused chemotherapy. He died shortly following diagnosis. In conclusion: A diagnosis of ENKTL should be considered when patients present with fever and expansive consolidation of the lung, which do not respond to antibiotics. To our knowledge, our patient was the first to undergo NGS for primary pulmonary ENKTL.