Source: Eur J Nucl Med  |  Posted 9 years ago

The single radioiodine regimen for elderly patients with enlarged thyroid glands and autonomous masses can be based on technetium-99m pertechnetate thyroid uptake under thyrotropin suppression (TcTU[_]s[]).

Researchers from University Hospital Bonn, and other centres in Germany and Switzerland, aimed to optimise treatment of diffuse and nodular toxic goitre using single doses of radioiodine based on TcTU[_]s[]. This acts as a surrogate for non-suppressible iodine turnover and the functional autonomous mass.

The study enrolled 438 patients, average age 70 years, with a mean thyroid volume of 54 ml. Of these, 261 experienced at least one episode of overt hyperthyroidism. The tissue absorbed doses from single radioiodine therapy ranged from 150 Gy for TcTU[_]s[] of between 1.5 and 2.49 percent to 300 Gy for a TcTU[_]s[] of at least 4.5 percent.

Thyroid volume declined by a mean 37 percent a year after treatment. At this time, 96 percent of patients showed normalised TcTU[_]s[] and 92 percent showed normal thyrotropin levels. Only 0.9 percent of patients developed hypothyroidism. Five patients showed recurrent hyperthyroidism.

The authors recommend selecting the dose of single radioiodine therapy based on TcTU[_]s[] for elderly patients with enlarged thyroid glands and autonomous masses, and who are likely to develop iodine-induced hyperthyroidism.