Localization of Tc-99m sestamibi and TI-201 in an unsuspected calcified intrathoracic mass.

Tc-99m MIBI and TI-201 uptake have been reported in benign and malignant lesions. However, concordant uptake of both radiotracers has been described infrequently. The authors report a patient with a case history of tuberculosis and breast cancer who underwent a TI-201 cardiac stress/planar study initially for complaints of angina pectoris, and 3 years later a follow-up Tc-99m MIBI cardiac study was completed for similar complaints. These studies incidentally revealed uptake of TI-201 and Tc-99m MIBI in a large left lung mass unchanged in size between the two studies. CT with intravenous contrast performed 2 months after the Tc-99m MIBI study revealed a 9 cm calcified soft-tissue mass in the left lung with adjacent pleural calcifications.