The Salivary Gland Function Of DTC Patients Before And After 131 Iodine Treatment Was Evaluated Semi-quantitatively By ^99mTcO₄^- Salivary Gland Scintigraphy

Objective:1.The salivary gland function of DTC patients before 13 liodine treatment was semiquantitatively analyzed by 99mTcO4-salivary gland scintigraphy.2.99mTcO4-salivary gland scintigraphy was used to evaluate salivary gland function in differentiated thyroid cancer patients treated with different cumulative doses of 131 iodine and its relationship with dose.Material and methods:Section 1:99mTcO4-salivary gland scintigraphy was performed in 41 healthy volunteers and 138 patients with differentiated thyroid cancer before initial 131 iodine-therapy.The regions of interest were delineated in bilateral parotid and submandibular glands,and the time radioactivity curves and semi-quantitative functional parameters were obtained.The main functional parameters were uptake index and secretion fraction after acid stimulation.The range of normal reference values of semi-quantitative functional parameters of healthy volunteers was calculated to evaluate salivary gland function of DTC patients before radioactive iodine treatment more objectively.Mann-whitney U test was performed on 138 DTC patients before 131 iodine treatment and 41 healthy volunteers.Section 2:In order to better evaluate the effects of different 131 iodine-treated cumulative doses on salivary gland function,109 DTC patients treated with 131 iodine-treated DTC were divided into groups.According to their cumulative dose,they were divided into three groups:Group Ⅰ:patients with a cumulative dose of 131 iodine-treated 50-149 mCi;GroupⅡ:131 iodine-treated patients with a cumulative dose of 150-299 mCi;Group Ⅲ:patients treated with 131 iodine at a cumulative dose of ≥ 300 mCi.99mTcO4-salivary gland scintigraphy was performed on these DTC patients 1-2 days before treatment and 3-6 months after treatment.ROI was delineated in bilateral parotid and submandibular glands,and time radioactivity curves and functional parameters（UI and EF）were obtained.99mTcO4-salivary gland scintigraphy was used to semi-quantitatively analyze the changes of salivary gland function in patients 3-6 months after different cumulative doses of treatment,and analyze the correlation between the changes and cumulative doses of treatment.Results:1.Analysis of salivary gland scintigraphy function in DTC patients before 131 iodine treatment1.1 Results of salivary gland scintigraphy function parameters in healthy volunteers.There were no statistically significant differences in gender,UI and EF of bilateral parotid gland and submandibular gland in 41 healthy volunteers（P>0.05）,which were consistent with normal distribution test.The uptake index of left and right parotid glands were 0.25±0.08 and 0.25±0.09,respectively.After acid stimulation,the maximum excretion fraction of left and right parotid glands was 75.33%±8.50%and 75.75%±7.60%,respectively.The uptake index of the left and right submandibular glands were0.28±0.12 and 0.27±0.11,respectively.The maximum secretion fractions of the left and right submandibular glands after acid stimulation were 59.85%± 9.04%and 61.20%± 8.91%,respectively.1.2 Comparative analysis of salivary gland scintigraphy function parameters between DTC patients and healthy volunteers.Among 138 DTC patients,12 showed impaired salivary gland function on salivary gland scintigraphy.The UI and EF of left and right parotid gland and submandibular gland in 138 DTC patients before 131 iodine treatment and 41 healthy volunteers showed no significant difference（P>0.05）.2.Comparative analysis of functional parameters of salivary gland scintigraphy in DTC patients 3-6 months after 131 iodine treatment:2.1 Compared with before 131 iodine treatment,UI and EF of bilateral parotid gland and submandibular gland in DTC patients in group Ⅰ showed no statistical significance 3-6 months after 131 iodine treatment（P>0.05）.In DTC group II,EF of bilateral parotid gland decreased significantly 3-6 months after 131 iodine treatment（P<0.05）,and there was no statistical significance in other bilateral parotid gland UI and bilateral submandibular gland UI and EF（P>0.05）.The UI and EF of bilateral parotid gland and submandibular gland of DTC patients in treatment group Ⅲ were significantly decreased 36 months after 131 iodine treatment（P<0.05）.2.2 Comparison between multiple groups in Ⅰ-Ⅲ group:there was no significant difference in bilateral parotid gland UI（P>0.05）,but there were significant differences in bilateral parotid gland EF and bilateral submandibular gland UI and EF among all groups（P<0.05）.2.3 Pairwise comparison between treatment groups:if the comparison between multiple groups is statistically significant,the comparison between multiple independent samples will be shown:（1）UI comparison:there was no statistical difference between two groups of parotid glands（P>0.05）;Only the treatment of bilateral submandibular gland was significantly different between group Ⅲ and group Ⅰ（P<0.05）,while there was no significant difference between other groups（P>0.05）.（2）EF comparison:There were statistically significant differences between right parotid gland treatment group Ⅲ and group Ⅱ and the treatment group Ⅰ（P<0.05）.There were statistically significant differences between the treatment group Ⅰ and Ⅱ and the treatment group Ⅲ（P<0.05）,while there were no statistically significant differences between the other groups（P>0.05）.Conclusion:1.Some patients may have salivary gland function injury before the first 131 iodine treatment after DTC.Therefore,the patient’s salivary gland history should be inquired in detail before the first 131 iodine treatment,and routine 99mTcO4-salivary gland dynamic scintigraphy should be performed to establish personalized baseline values of salivary gland uptake and excretion functions.For some patients with impaired salivary gland function,more active protective intervention measures in the course of treatment are also helpful to evaluate the effect of 131 iodine treatment on salivary gland function more accurately.2.With the increase of cumulative dose of 131 iodine after DTC treatment,salivary gland function of DTC patients could be damaged to varying degrees,and the degree of damage was aggravated with the increase of cumulative dose.Therefore,99mTcO4-salivary gland scintigraphy should be performed regularly after 131 iodine-treated to detect salivary gland functional damage in time for early intervention.