Radioprotection of salivary glands by amifostine in high-dose radioiodine therapy investigated in a new rabbit animal model

english

1997

volume 31, issue 3

Onkološki inštitut Ljubljana

Salivary gland damage following high-dose radioiodine treatment (HD-RIT) is a well known side effect. Since differentiated thyroid cancer (DTC) has a very good prognosis, the reduction of long-term side effect is of major interest. Therefore, the radioprotective effect of amifostine was investigated in a rabbit animal model. Quantitative salivary gland scintigraphy was performed on5 rabbits prior to and up to 3 months after HD-RIT applying 1 GBq I-131. Theuptake of Tc-99cm-pertechnetate was calculated as a measure of parenchymal function. Three animals received 200 mg/kg amifostine prior to HD-RIT, and twoserved as controls. Salivary glands were examined histopathologically. In two control rabbits HD-RIT significantly (p<0.001) reduced pertechnetate uptake by 63% and 46% in parotid and submandibular glands, respectively, and lipomatosis was found histopathologically. In contrast, in three rabbits treated with amifostine parenchymal function was not decreased significantly (p=0.953), and lipomatosis was negligible. In conclusion, salivary gland impairment induced by HD-RIT can be evaluated quantitatively by salivary glandscintigraphy in rabbits, and amifostine significantly reduced salivary gland damage induced by HD-RIT. These encouraging results need furtner evaluation in patients since in may help to increase the quality of life of patients with diffentiated thyroid cancer.

10.11.2023