[Pulmonary extranodal natural killer/T-cell lymphoma: clinical analysis of three cases].

To improve the understanding of pulmonary involvement of extranodal natural killer/T-cell lymphoma (ENKTL) by analyzing the clinical manifestations, imaging and pathological features of this disease. Three cases of ENKTL, proven by pathological diagnosis in Fuzhou General Clinical Medical College of Fujian Medical University, were retrospectively analyzed. All of the 3 cases were males, aged 74, 61 and 49 years, respectively. The main clinical symptoms included cold and fever. One patient had nasal congestion and runny nose. Chest CT showed multiple lung nodules (3), masses (2) and patchy shadows (2), with irregular lesions and clear boundaries. The 3 cases had been misdiagnosed as community acquired pneumonia, and treated with intravenous injection of moxifloxacin. ENKTL was confirmed by CT-guided percutaneous biopsy with immunohistochemical staining, which showed that 3 cases were positive for CD(56), CD(2), in situ hybridization for EBV encoded RNA (EBER), while negative for CD(20), and 2 cases were positive for CD(3), Granzyme B; and 1 case was positive for T-cell intracytoplasmic antigen-1. All 3 patients received chemotherapy, but 2 patients died, one of rejection 1 month later after bone marrow transplantation. One patient had improved after chemotherapy with follow-up. ENKTL should be considered when patients presented with fever, multiple lung nodules or consolidations which were non-responsive to antibiotics. Lung biopsy was the key to diagnosis.