Gallium-67 scintigraphy in evaluation of malignant lymphoma of the thyroid gland.

During the period from 1982 to 1994, a total of 45 67Ga scintigrams were performed in 12 patients with malignant lymphoma of the thyroid gland. Eight scintigrams were performed before treatment, 12 during the course of radiation therapy, and 25 after treatment. Scintigrams before treatment showed intense uptake in the thyroid masses irrespective of their size. Two of four scintigrams revealed no accumulation in the clinically remaining masses that were given a radiation dose of less than 20 Gy. No accumulation or thyroid masses were observed in cervical regions that received an irradiation dose of 20 Gy or more. Distant involvement in the upper half of the body could be detected by 67Ga scintigraphy in all cases, while there were two false negative lesions in the abdominal or pelvic cavity. Abdominopelvic lesions involving the gastrointestinal tract were observed in four cases, including two autopsied cases. 67Ga scintigraphy is useful for the evaluation of malignant lymphoma of the thyroid gland, but other examinations are recommended when 67Ga uptake is observed in the abdominal or pelvic cavity.