[Thallium-201 and gallium-67 scintigraphies in the diagnosis of pneumoconiosis combined with lung cancer].

Thallium-201 (201Tl) and Gallium-67 (67Ga) scintigraphies were performed on 62-year-old male with silicosis combined with lung cancer (squamous cell carcinoma). In 67Ga and early 201Tl images, radiotracer uptakes were observed in both sites of cancer and silicosis, and thus, it was impossible to differentiate cancer mass from the large opacity of pneumoconiosis. On the other hand, in the 201Tl delayed images, 201Tl was localized only in cancer mass, while it was washed out from the large opacity. Our findings indicated that 201Tl early and delayed scintigraphy findings were very useful to differentiate lung cancer from silicosis.