Primary pulmonary
lymphoma is a
rare disease, and non-B
cell lymphomas (
T-cell and
natural killer cell lymphomas) involving the
lung parenchyma are uncommonly reported. The most common radiological feature of pulmonary parenchymal
lymphoma is a single mass or nodule. A 49-year-old
woman with
dyspnea was referred with suspicion of severe
pneumonia. A
chest radiograph showed diffuse nodular infiltration in both
lungs. Acute
respiratory failure was severe and rapidly progressive, so she was managed with a
mechanical ventilator under the impression of
acute respiratory distress syndrome (ARDS). A
bronchoalveolar lavage and
lung biopsy by
video-assisted thoracic surgery revealed NK-
T cell lymphoma. We
report a case of extranodal NK-
T cell lymphoma presenting as ARDS.