Malignant Tracheoparenchymal Fistula in Primary Mediastinal B-Cell lymphoma detected on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

Acquired tracheobronchial fistulas are a relatively uncommon complication. Among them, tracheo-mediastinal-parenchymal fistulas are particularly rare. Most of the reported cases are associated with concurrent chemoradiotherapy in lung cancer. It has not been reported in lymphomas. These fistulas are associated with high mortality due to infection and bleeding, and there is no consensus on a definitive optimal therapy. Here, we present a case of tracheoparenchymal fistula in a follow-up primary mediastinal B-cell lymphoma case. This case highlights the utility of fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in the initial diagnosis and follow-up of lymphoma. The PET/CT could show demonstrate the residual disease and differentiate it from other therapy-related benign changes.