Assessment of Salivary Gland Function Using Salivary Scintigraphy in Pre and Post Radioactive Iodine Therapy in Diagnosed Thyroid Carcinoma Patients

Thyroid carcinoma represents less than 1% of all cancers. The first line of treatment for thyroid cancer is partial/total thyroidectomy. High-dose Iodine(131) therapy using Iodine radioisotopes is commonly used in patients with well differentiated thyroid carcinoma after total thyroidectomy. In this process, the non-thyroidal tissues, such as, salivary gland, stomach and breast tissues also take up radioactive iodine. Salivary gland scintigraphy is widely accepted as a sensitive and valid method for evaluation of salivary gland dysfunction after Radioactive Iodine(131) Therapy (RIT). To assess and compare the salivary flow rates, relative uptake and ejection fractions in parotid and submandibular glands just before and one month after Iodine(131) therapy. The study was conducted on 24 patients diagnosed with well differentiated thyroid carcinoma who underwent partial/total thyroidectomy and were due for radioactive iodine therapy. These patients were divided into two groups based on the lesion based dosimetry (Group A: 60-100Gy; Group B: 100-150Gy). Salivary gland assessment was done by salivary gland scintigraphy before and after RIT. The data collected was tabulated and statistically analysed using SPSS software version16 using paired t-test and individual sample t-test. A statistically significant difference in the uptake percent and ejection fraction percent in the parotid and submandibular glands before RIT and one month after RIT was observed in the study. We inferred from the study that there was an overall decrease in uptake percent and ejection fraction percent one month post RIT in both parotid and submandibular glands. Also, a statistically significant difference was noted in the uptake and ejection fraction percent between Group A and Group B concluding the fact that the damage is dose related.