LBSAT144 Single-center Experience With Hyperparathyroidism-jaw Tumor Syndrome - Where Do We Stand?

Background Hyperparathyroidism-jaw tumor (HPT-JT) syndrome is a heritable form of primary hyperparathyroidism (PHPT) associated with tumors in parathyroid, jaw, kidney, and uterus. This work aims to provide a natural history of HPT-JT from a long-term follow-up of a large single-institution cohort. Methods We identified patients with HPT-JT seen under the natural history study of parathyroid disorders from 1991-2020 and analyzed their disease manifestations and treatment outcomes. Results Sixty-six patients (50% males) from 32 kindreds with HPT-JT (genotype-positive: 46, presumed genotype-positive: 20). Median age at presentation of index patients was 24 [19-33] years. PHPT was prevalent in 51/61(84%) patients, of which seven had ectopic parathyroid tumors and 20/50 (40%) had multi-gland disease. Eighty-two parathyroid tumors were removed from 52 patients through 66 surgeries -17/66 (26%) unilateral; 23/66 (35%) bilateral neck explorations. Parathyroid cancer (PC) was seen in 16/78 tumors (21%), atypical parathyroid in 2/78(3%), parathyroid adenoma (PA) in 12/78 (15%), hyperplasia in 27/78 (35%) and microscopically normal but enlarged parathyroid in 21/78 (27%). PAs had median tumor size 10 [7-17] mm, PC: 19 [11-25] mm. We found a significant correlation between tumor size and serum PTH (r=0.55, p=0. 007). Uterine tumor was second most common disease manifestation (10/36 females, 28%) - initial manifestation in 5/10. Median age of presentation was 18 [15-21] years with presentations of menorrhagia, abdominal pain, or miscarriage. The histology of uterine tumors included adenomyoma, fibroids or leiomyomata. JT was noted in 5/70 (7%) patients (three mandibular, two maxillary tumors) - initial manifestation in 3/5. Median age of presentation with JTs was 23 [20-31] years. Microscopically, JTs were diagnosed as cysts (n=2), cemento-ossifying fibroma (n=2) and fibro-osteoid lesions (n=1). Kidney tumors were observed in three patients - one presented with abdominal pain, two were diagnosed on surveillance scans. Median age at presentation was 25 [6-44] years. Two related patients had bilateral mixed epithelial and stromal tumors while a 6-year-old male had Wilm's tumor. Median age at last follow-up was 37 [28-49] years. Recurrent PHPT was seen in 5/35(14%) patients with PA or hyperplasia (Median recurrence time: 10[7 - 16] years) and 12/15(80%) with PC (Median recurrence time: 2[1 - 5] yeas. Co-existing psychiatric disorder, mainly depression and anxiety were seen in 16/68 (24%) patients, consistent with published literature for other chronic conditions. Conclusion Most (60%) patients with HPT-JT have single-gland disease with recurrence seen in only a minority of patients (14%) with PAs. JTs are not as common as the name suggests while uterine tumors appear to be relatively frequent. Acknowledgement: This research is supported by the Intramural Research Program of NIDDK and NCI. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.