EP19 – Sialoadenitis and xerostomia secondary to I-131 therapy in patients with differentiated thyroid cancer and who took sialagogues: a prospective study

•   Wu, Di¹; Turner, Deniek²; Orquiza, Michael³; Burman, Kenneth⁴; Wartofsky, Leonard⁴; Van Nostrand, Douglas⁵ 1 MedStar Health Research Institute, Washington D.C., USA 2 Howard University, Washington D.C., USA 3 Department of Neuroscience, Georgetown University, Washington, DC , USA. 4 Division of Endocrinology, Medstar Washington Hospital Center, Washington D.C., USA 5 Division of Nuclear Medicine, Medstar Washington Hospital Center, Washington D.C., USA   Background/Purpose: The prophylactic use of sialogogues in differentiated thyroid cancer(DTC) patients against salivary side effects(SSE) of I-131 therapy is controversial. Objectives: Our aim was to characterize the frequency, duration and severity of I-131-induced sialoadenitis/xerostomia in patients who took sialagogues prophylactically. Methods: For this prospective study, six surveys were designed to assess the above metrics at pre-therapy (<1month) and post-therapy (i.e., day1&5-7 and month3,6&12).  The inclusion criteria were: ?18yo, DTC, and I-131 therapy as an inpatient at MedStar WashHospitalCtr. Patients were excluded from the sialoadenitis data if they had a preexisting sialoadenitis(PSA) and from the xerostomia data if they had a pre-existing xerostomia(PXE). Results: Ninety-nine patients consented. Of the 88 patients that did not have PSA, 33 reported pain/swelling indicative of sialoadenitis. Peak time of onset was on Day1(20/33 [61%]). Three patients reported sialoadenitis lasting >1 month with the longest duration of 5 months. On an intensity scale, 1/33(3%) rated pain as severe, 20/33(61%) as moderate, and 12/33(36%) as mild. Of the 80 patients that did not have PXE, 35 reported xerostomia. Peak time of onset was on Day1(24/35 [69%]). Six patients reported xerostomia lasting >1 month with the longest duration of 4 months. On an intensity scale, 9/35(26%) rated xerostomia as severe 21/35 (60%) as moderate, and 5/35(14%) as mild. Conclusion: This report describes the frequency, duration and severity of I-131-induced sialoadenitis and xerostomia in DTC patients who took sialogogues. Further prospective studies are needed to evaluate the specific methods of sialogogue administration of that prevents/alleviates SSE.