RESUMO
OBJECTIVES: To assess the effects of amifostine on salivary glands in radioactive iodine-treated differentiated thyroid cancer. METHODS: We searched the MEDLINE, EMBASE and the Cochrane Library for randomized controlled clinical trials which compared the effects of amifostine with those of placebo or acid-stimulating agents. RESULTS: Two randomized controlled clinical trials with a total of 130 patients were included. Both studies had a low risk of bias. There were no statistically significant differences between the effects of amifostine and acid-stimulating agents on the incidence of xerostomia (RR 0.24, 95% CI 0.01 to 9.52), the decrease of scintigraphically measured uptake of (99m)Tc by the parotid (RR 0.30, 95% CI -2.28 to 2.88) or submandibular glands (RR 1.90, 95% CI -1.46 to 5.26) at 12 months, or the reduction in blood pressure (RR 5.00, 95% CI 0.25 to 99.16). Neither of the included trials investigated death from any cause, morbidity, health-related quality of life or costs. CONCLUSION: The results of two randomized controlled clinical trials suggest that amifostine has no significant radioprotective effects on salivary glands in radioactive iodine treatment of differentiated thyroid cancer. The use of acid-stimulating agents to increase salivation should remain the first choice during radioactive iodine treatment of differentiated thyroid cancer. Patients should also be well informed of the importance of hydration and acid stimulation.
Assuntos
Amifostina/farmacologia , Doses de Radiação , Protetores contra Radiação/farmacologia , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/efeitos da radiação , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/radioterapia , Amifostina/efeitos adversos , Animais , Humanos , Radioisótopos do Iodo/uso terapêutico , Protetores contra Radiação/efeitos adversosRESUMO
BACKGROUND: Radioactive iodine treatment for differentiated thyroid cancer possibly results in xerostomia. Amifostine has been used to prevent the effects of irradiation to salivary glands. To date, the effects of amifostine on salivary glands in radioactive iodine treated differentiated thyroid cancer remain uncertain. OBJECTIVES: To assess the effects of amifostine on salivary glands in high-dose radioactive iodine treated differentiated thyroid cancer. SEARCH STRATEGY: Studies were obtained from computerized searches of MEDLINE, EMBASE, The Cochrane Library and paper collections of conferences held in Chinese. SELECTION CRITERIA: Randomised controlled clinical trials and quasi-randomised controlled clinical trials comparing the effects of amifostine on salivary glands after radioactive iodine treatment for differentiated thyroid cancer with placebo and a duration of follow up of at least three months. DATA COLLECTION AND ANALYSIS: Two authors independently assessed risk of bias and extracted data. MAIN RESULTS: Two trials with 130 patients (67 and 63 patients randomised to intervention versus control) were included. Both studies had a low risk of bias. Amifostine versus placebo showed no statistically significant differences in the incidence of xerostomia (130 patients, two studies), the decrease of scintigraphically measured uptake of technetium-99m by salivary or submandibular glands at twelve months (80 patients, one study), and the reduction of blood pressure (130 patients, two studies). Two patients in one study collapsed after initiation of amifostine therapy and had to be treated by withdrawing the infusion and volume substitution. Both patients recovered without sequelae. Meta-analysis was not performed on the function of salivary glands measured by technetium-99m scintigraphy at three months after high dose radioactive iodine treatment due to the highly inconsistent findings across studies (I(2) statistic 99%). None of the included trials investigated death from any cause, morbidity, health-related quality of life or costs. AUTHORS' CONCLUSIONS: 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.