Salivary gland protection by amifostine in high-dose radioiodine treatment: results of a double-blind placebo-controlled study. Limited cytoprotective effects of amifostine in high-dose radioactive iodine 131-treated well-differentiated thyroid cancer patients: analysis of quantitative salivary scan.
Salivary gland impairment is a well-recognized side effect following high-dose radioiodine treatment (HD-RIT). Since differentiated thyroid cancer has a good prognosis, reduction of long-term side effects is important. Therefore, the effect of amifostine was studied in HD-RIT.
                Parenchymal function was assessed by quantitative salivary gland scintigraphy performed prospectively in 50 patients with differentiated thyroid cancer before and 3 months after HD-RIT with either 3 GBq iodine ((131)I) (n=21) or 6 GBq (131)I (n=29) in a double-blind, placebo-controlled study. Twenty-five patients were treated with 500 mg/m2 amifostine intravenously before HD-RIT and 25 patients served as controls, who received physiologic saline solution. Xerostomia was graded according to World Health Organization (WHO) criteria.
                Before HD-RIT in 25 control patients, uptake of technetium-99m (99mTc)-pertechnetate was 0.45%+/-0.16% and 0.42%+/-0.16% in parotid and submandibular glands, respectively. Three months after HD-RIT, parenchymal function was significantly (P < .001) reduced by 40.2%+/-14.1% and 39.9%+/-15.3% in parotid and submandibular glands, respectively. Nine control patients developed grade I and two grade II xerostomia. In 25 amifostine-treated patients, uptake of 99mTc-pertechnetate was 0.46%+/-0.16% and 0.43%+/-0.17% in parotid and submandibular glands, respectively. Three months after HD-RIT, parenchymal function of salivary glands was not significantly altered (P=.691) and xerostomia did not occur in any of these patients.
                Parenchymal damage in salivary glands caused by HD-RIT can significantly be reduced by amifostine, which may improve the quality of life of patients with differentiated thyroid cancer. The aim of present study was to investigate the cytoprotective effect of amifostine on salivary glands in 131I-treated differentiated thyroid cancer (DTC) patients using serial quantitative analysis of salivary gland scans.
                Serial quantitative salivary scintigraphies were performed in 80 newly diagnosed DTC patients (9 men, 71 women; mean age, 43.2 years old; range, 21-58 years old). Forty-two patients were assigned randomly to the amifostine treatment group, which received 300 mg/m2 amifostine intravenously before 131I administration.
                In both amifostine-treated and nontreated groups statistically significant declines of functional parameters after 131I treatment were revealed by quantitative salivary scintigraphy in DTC patients. Amifostine pretreatment did not prevent the parenchymal damage to major salivary gland function after 131I treatment (F = 1.37, p = 0.2461). However, the dose of 131I had significant effects on salivary gland function after 131I treatment (F = 9.72, p = 0.0002).
                The present study did not show cytoprotective effects of amifostine for DTC patients treated with 131I.
Results from two randomised controlled clinical trials suggest that the amifostine has no significant radioprotective effects on salivary glands in high-dose radioactive iodine treated differentiated thyroid cancer patients. Moreover, no health-related quality of life and other patient-oriented outcomes were evaluated in the two included trials. Randomised controlled clinical trials with low risk of bias investigating patient-oriented outcomes are needed to guide treatment choice.