Studys About The Best Time Of Giving Vitaminec After Radiododine-131Therapy In Patients With Differentiated Thyroid Cancer

Objective This study is to explore the best time of using vitamin Cto protect salivary gland radiation injury in patients with differentiatedthyroid cancer after131I therapy.Methods120total cases of thyroidectomy of differentiated thyroidcancer were randomly divided into group A or B (n=60), which wereadministrated with vitamin C in either2hours or24hours after treatmentof131I in order to reduce damage caused by radioactivity of131I. Salivaryglands dynamic images were taken six months later and time-activitycurves were drawn; then parotid and submandibular region of interest (ROI)and appropriate organization as background correction were lain out;finally, gland uptakes ratios (UR) and excretory index at maximumsecretion (MSR) were calculated.Result UR and MSR of left parotid gland are3.16±1.12,61,13%±13.85%in group A and2.84±1.10,58.56%±12.26%in group B; UR andMSR of right parotid gland are3.08±1.02,63.70%±14.12%in group Aand2.82±0.95,59.40%±12.27%in group B; UR and MSR of leftsubmandibular gland are2.10±1.01,47.52%±12.74%in group A and2.15±0.97,49.92%±12.93%, in group B; UR and MSR of right submandibular gland are2.21±1.05,49.98%±13.20%in group A and2.15±0.97,49.37%±13.04%in group B. The differenence of the result in group A andB was not statistically significant (P>0.05).Conclusion Salivary stimulation with vitamin C in both2and24hours after131I administration has no effect on salivary protection indifferentiated thyroid cancer patients.