EBUS-guided Cryobiopsy-Proven Anthracotic Mediastinal Lymph Node Mimicking Malignancy on FDG PET-CT: A Case Report.

Anthracotic mediastinal lymph nodes are an uncommon cause of intense fluorodeoxyglucose (FDG) uptake on positron-emission tomography-computed tomography (PET-CT), often mimicking malignancy and leading to diagnostic uncertainty. Here, we report the case of a 67-year-old Asian male with FDG-avid mediastinal lymphadenopathy that was highly suspicious for metastatic disease. Subsequent endobronchial ultrasound-guided lymph node sampling demonstrated anthracosis without evidence of malignancy or infection. Recognition of this rare benign entity prevented cancer upstaging and unnecessary treatment. This case highlights the importance of histopathological confirmation of PET-positive mediastinal lymph nodes, particularly in patients with suspected or known malignancy, to ensure accurate diagnosis and appropriate clinical management.