摘要:Primary pulmonary non-Hodgkin lymphoma is a rare entity, accounting for 3-4% of extranodal non-Hodgkin lymphomas. Indolent primary pulmonary non-Hodgkin lymphomas are the most frequent types, with the MALT subtype representing majority of cases. Other indolent subtypes of B-cell primary pulmonary lymphomas are rare. We present the case of a 56-year-old patient, non-smoker, who presents for pain in the right hemithorax, worsened by deep inhales. Pulmonary X-ray showed a right paramediastinal superior and medial lobe homogenous opacity with faded contour. Thoracic computed tomography scan described a dense right superior mediastino-pulmonary tumoral mass, the absence of hilar or mediastinal adenopathies. In this context, an ultrasound-guided transbronchial needle aspiration was performed. Histopathology and immunohistochemistry confirmed the diagnosis of primary pulmonary small B-cell non-Hodgkin lymphoma. After 6 chemotherapy cycles, from a clinical and imagistic (thoracic CT scan) point of view, the response was favourable. Positron emission tomography (PET/CT) aspect indicated a complete metabolic response to treatment.