MON-781 Reoperative Parathyroidectomy: Recognizing Unique Risk Profiles

Abstract Disclosure: S. Xie: None. T. Gruen: None. T. Hu: None. A. Sinha: None. C.B. Jensen: None. D.T. Hughes: None. S.C. Pitt: None. H.J. Underwood: None. Background: Reoperative parathyroidectomy (R-PTX) for patients who previously underwent parathyroidectomy (PTX), thyroidectomy (TX), or a non-endocrine cervical procedure (NECP) is more complex and has a higher risk-profile compared to initial parathyroidectomy. Despite this, limited data exist examining how the index cervical operation uniquely affects outcomes after R-PTX. This study aimed to characterize outcomes after R-PTX based on index operation including surgical failure, permanent hypoparathyroidism, parathyroid autotransplantation, and recurrent laryngeal nerve (RLN) injury. Methods: This retrospective cohort study examined adult patients who underwent R-PTX (CPT 60502) for primary hyperparathyroidism at a single academic tertiary referral center from 2016-2024. Patients were stratified by index cervical procedure (PTX, TX, and NECP). Immediate biochemical cure was defined as absolute post-excision intraoperative PTH level <65 pg/mL, and surgical failure was defined as final intraoperative PTH >65 pg/mL. Permanent hypoparathyroidism was defined as PTH <6 pg/mL greater than 6 months post-operatively. Operative notes were reviewed to identify recurrent laryngeal nerve injury, loss of nerve signal, and parathyroid autotransplantation. Results: Among 242 patients who underwent R-PTX, 173 (71.5%) previously underwent PTX, 59 (24.4%) TX, and 10 (4.1%) NECP. Patients who underwent prior PTX were more likely to undergo parathyroid autotransplantation (p<0.001) or have surgical failure/persistent disease (p=0.005) than those with history of TX or NECP. Patients with a history of prior subtotal PTX had increased odds of undergoing autotransplant (OR 9.5, 95%CI 2.6-35.8), while younger patients had increased odds of surgical failure (OR 1.06, 95% CI 1.01 - 1.12). Patients who underwent prior PTX had less time between R-PTX and their index surgery (p<0.001). RLN injury occurred in 6 (2.5%) patients with no difference by index procedure (p=0.731). Rates of permanent hypoparathyroidism after R-PTX were similar among groups and occurred in 29 (16.7%) of patients who underwent prior PTX, 5 (8.5%) patients who underwent TX, and no patients with NECP (p=0.386). Conclusions: R-PTX has a unique risk profile based on the patient’s index operation. Patients who underwent previous PTX experience higher rates of surgical failure and parathyroid autotransplantation than patients with prior TX or NECP. Surgeons should tailor preoperative risk counseling for patients undergoing R-PTX based upon index procedure. Presentation: Monday, July 14, 2025