Diffuse bony uptake of thallium-201-chloride in the granulocyte colony-stimulating factor-producing lung carcinoma

Diffuse uptake of 201TI in the axial bone is reported in a patient with large cell carcinoma of the lung who showed leukocytosis and an increased concentration of granulocyte colony-stimulating factor (G-CSF) in plasma. The abnormal bony uptake of 201TI disappeared in association with normalization of the elevated plasma G-CSF level after complete tumor resection. The production of G-CSF was confirmed by immunoperoxidase staining of the tumor tissue.