Metallic foreign body or an illusion?

A male patient, aged 70, with a confirmed diagnosis of squamous cell cancer (cT4N2M0) affecting the Right Upper Lobe (RUL) of the lung. A further evaluation using Computerized Tomography (CT) scanning revealed a partial response in the RUL mass, along with the incidental discovery of a FB with a metal density in the Left Main Bronchus (LMB) measuring 640 Hounsfield Units (HU). The individual exhibited no symptoms and did not have any previous indications of foreign body aspiration. The subsequent bronchoscopic assessment revealed the presence of a circular and smooth FB in the LMB, specifically identified as a tablet.