Co-occurrence of Primary Tracheal Diffuse Large B-Cell Lymphoma and Pulmonary AA Amyloidosis: A Unique Case Report.

Primary tracheal diffuse large B-cell lymphoma (DLBCL) is a rare, aggressive, but potentially curable malignancy that is difficult to diagnose and treat. We herein report a 93-year-old Japanese man diagnosed with primary tracheal DLBCL after presenting with progressive dyspnea due to severe upper tracheal stenosis during follow-up for pulmonary amyloidosis. Following the diagnosis, the patient was treated with corticosteroids, followed by R-CHOP chemotherapy, resulting in a therapeutic response. The patient's history of pulmonary amyloidosis may have contributed to the development of tracheal DLBCL. An evaluation of the risks and benefits of various therapeutic interventions is crucial for providing optimal patient-specific care.