Abstract
We report a very rare case of primary endobronchial peripheral T-cell lymphoma (PTCL) not otherwise specified (NOS), which presented as an endobronchial tumor obstructing the main airway. An 81-year-old man was referred to our hospital for a 1-month history of productive cough and wheeze. Computed tomography revealed chronic pyothorax with calcified foci in the right lung and a mass inside the bronchus intermedius. Flexible bronchoscopy identified an endobronchial tumor obstructing the bronchus intermedius. The biopsy specimen showed an infiltration composed predominantly of small atypical lymphocytes. Immunohistochemical analyses demonstrated that the proliferating cells were positive for CD3, CD4, and CD5 and negative for CD8 and CD20. Pathological tests confirmed that the case was PTCL-NOS. PTCL-NOS should be considered in the differential diagnosis of endobronchial tumors.