TSH stimulation and other ways to increase the uptake in normal and tumorous thyroidal tissue

The use of bovine TSH is still the most important means for increasing the radioiodine uptake in functionally active tissue. The increase is more marked in normal thyroid tissue (where 2.5 fold increase of the initial value can be expected); but the tumorous tissue reacts to the stimulation, though less substantially (mean increase to 1.5). In intact thyroid gland the increase of uptake is more pronounced with lower uptake in the remaining thyroid tissue; in functionally active tumor this relation cannot be proved. With very low uptake in the tumorous tissue (below 2.5%/24 h) the chance to achieve practically significant increase is negligible. The complications with TSH administration appear especially with repeated application, the proportion of more serious side effects being low. The use of diuretic regime with the iodine depletion simultaneously with TSH stimulation is rather pretentious for the patient; it substantially increases the uptake in the tumorous tissue (again to 2.6 times), although more markedly decreases the iodine excretion in the urine what leads to higher danger of complications caused by radioiodine therapy. The use of TSH stimulation to increase the uptake in the tumorous tissue had not yet been shown to be useful.