Lyden, Melanie

Introduction Previous studies have demonstrated that C 11 choline positron emission tomography/computed tomography (Choline-PET/CT) can localize abnormal parathyroid glands in the reoperative setting. This study assesses a large volume of patients with primary hyperparathyroidism (1HPT) who underwent Choline-PET/CT to confirm its utility in the setting of negative or equivocal conventional imaging. Methods All patients who underwent Choline-PET/CT for evaluation of 1HPT from July 2017 to July 2024 at a single institution were reviewed. Inclusion criteria were patients who underwent parathyroidectomy and had lab testing to assess for cure (defined as >50% drop from baseline PTH and into normal range, or resolution of hypercalcemia at follow-up). Sensitivity, positive predictive value (PPV), false negative rate (FNR), and accuracy were compared to conventional imaging (neck ultrasound, parathyroid scan, and parathyroid four-dimensional CT (4D-CT)). Subgroup analysis was conducted comparing sensitivity of modalities among index operations and separately in reoperations. Results 84 patients were included for analysis. 61 failed to localize on at least one conventional modality, and 15 failed to localize on all conventional studies. 67 patients (80%) achieved cure, of which 53 were reoperations. Choline-PET/CT outperformed conventional modalities across sensitivity, PPV, FNR, and accuracy. Choline-PET/CT also outperformed conventional modalities when comparing sensitivity in both subgroups. Conclusion C 11 choline-PET/CT is a valuable imaging modality in the reoperative setting and demonstrates utility for index operations. It provides localization when other modalities fail and allows for a high surgical cure rate. Further investigation into its utility as a primary imaging modality is warranted.

Abstract Disclosure: B. Salama: None. O. Hamidi: None. T.S. Wang: None. A. Sada: None. M.A. Habra: None. P. Dogra: None. A.P. Dackiw: None. S.C. Oltmann: None. S. Mirfakhraee: None. I. Lingvay: None. T. Mckenzie: None. T. Foster: None. M. Lyden: None. B. Dy: None. V. Balderrama Brondani: None. I. Bancos: None. Background: Patients with mild autonomous cortisol secretion (MACS) are at risk for adrenal insufficiency (AI) after unilateral adrenalectomy. Guidelines recommend initiating glucocorticoid replacement post-adrenalectomy. However, identifying patients at risk and accurately diagnosing AI can enable individualized management. Objectives: Determine the prevalence, duration and predictors of postoperative AI after unilateral adrenalectomy for MACS and compare baseline and peak cortisol post cosyntropin stimulation test (CST) In diagnosing AI. Methods: We conducted a multicenter retrospective cohort study of patients with MACS who underwent unilateral adrenalectomy and post-operative CST evaluation between January 1, 2013, and August 31, 2024. MACS was defined as cortisol >1.8 mcg/dL following overnight administration of 1 mg dexamethasone (DST-cortisol). AI was diagnosed when post-operative day 1 early morning baseline cortisol was <10 μg/dL and/or CST peak cortisol was <18 μg/dL. Baseline and peak cortisol levels were considered concordant when both met cut-offs. Biochemical (BSS) and clinical (CSS) severity scores were calculated. Results: Among 281 adults with MACS (80% women, median age 57 years, interquartile range [IQR] (47-64), the median adenoma size was 3.0 cm (IQR, 2.3-3.9), and 62 (22%) had bilateral disease. The median BSS was 4 (IQR, 3-5), and the median CSS was 6 (IQR, 2-11). Postoperative AI was diagnosed in 153 (54.5%) patients. A multivariable analysis showed that a higher BSS (OR = 1.17, 95% CI 1.01-1.36) and younger age at diagnosis (OR = 0.64, 95% CI 0.50-0.81), but not sex, BMI, or laterality, were associated with AI. Diagnosis of AI was concordant based on the baseline and peak CST cortisol cutoffs in 78% of patients. Diagnosis of AI was discordant in 22%: in 35 patients (12%), baseline cortisol was <10 μg/dL, but CST peak cortisol was ≥18 μg/dL, and in 28 cases (10%), baseline cortisol was ≥10 μg/dL, but CST peak cortisol was <18 μg/dL. Patients with bilateral MACS were more likely to have discordant results (32% vs. 19%, P < 0.001). During a median postoperative follow-up period of 15.4 months, 108 patients (70.6%) recovered from AI. The median time to recovery was 3.9 months (IQR, 3-5.9), with 41% recovering by 3 months, 60% by 6 months, and 73% by 12 months. The median time to recovery was associated with baseline BSS: mild: 3 months, moderate: 4.7 months, and severe: 14.5 months. Conclusion: We found that more than half of patients with MACS develop postoperative AI, with 50% recovering by 4 months post-surgery. BSS was associated with both the development and duration of AI. Baseline and CST peak cortisol results were concordant only in 78% of patients, thus performing both should be considered for an accurate diagnosis of AI. Presentation: Sunday, July 13, 2025

ABSTRACT Introduction The American Association of Endocrine Surgeons (AAES) drafted Entrustable Professional Activities (EPAs) for Endocrine Surgery (ES) to assess general surgery residents and ES fellows in core topics. Here, we examine learner and teacher concordance of entrustability ratings. Methods Fourteen EPAs were defined (10 “core”–6 with pre‐, intra‐, and post‐operative phases, four single‐phase–and four elective EPAs). Ten institutions collected three‐item micro‐assessments (MAs) of learner EPA performance using a web‐based platform, where entrustment was assessed on observable behaviors using a five‐point scale. Learner provided self‐assessment ratings, while teachers separately assigned ratings for the same activities. Spearman rank correlation tests were applied to compare learner‐teacher ratings for EPAs. Results MAs ( n = 698) were submitted between 7/2022‐9/2023. Programs submitted between 3 and 468 MAs. Among 3‐phase core EPAs, the intraoperative phase was most assessed ( n = 496), followed by pre‐ and post‐operative phases ( n = 108 and 55, respectively). Thirty‐nine single‐phase EPAs were submitted. Learner self‐assessment and teacher ratings were equivalent for 32% of pre‐operative EPAs, 53% of intra‐operative EPAs, 29% of post‐operative EPAs, and 64% of single phase of care EPAs. Spearman rank correlation between teacher and learner ratings for all phases of care combined was 0.66. Correlation was highest for the intra‐operative phase (0.73), followed by single‐phase (0.65), pre‐operative phase (0.27), and post‐operative phase (0.20). Rating concordance did not differ when high and low scores were examined independently. Learners were more prone to underestimate performance than to overestimate it when ratings were discordant. Conclusions Learners' self‐assessment and teacher ratings of endocrine surgery EPAs are strongly concordant with operative technical skills. However, learners often underestimate their performance of pre‐ and post‐operative care compared to faculty ratings when using EPAs.

Abstract Context Data on giant pheochromocytomas (PHEOs), defined based on size 10 cm or greater, are scarce. Objective This work aimed to compare presentation, management, and outcomes of patients with giant vs non–giant PHEOs. Methods A retrospective cohort study was conducted in a referral center from 2000 to 2023. Consecutive patients with giant PHEOs and randomly chosen patients with non–giant PHEO (referents) were studied at a 1:6 ratio. Outcomes included perioperative complications, metastases, and mortality. Results Of 828 patients with PHEOs, 31 (3.7%) had giant PHEO (median size 12 cm, interquartile range [IQR] 10.0-13.5 cm). In comparison to referents (n = 186, median size 4 cm, IQR, 2.9-5.0 cm), patients with giant PHEO had more symptoms of catecholamine excess (median of 2 vs 1; P = .04) and presented with a higher prevalence of severe catecholamine excess (76% vs 30%; P < .0001). Adrenalectomy was performed in 94% of patients with giant PHEOs and 100% of referents. In addition to preoperative α-adrenergic blockade (89%), metyrosine was used in 14 (7%) patients, mostly in patients with giant PHEOs (26% vs 3%; P < .0001). Patients with giant PHEOs had a higher perioperative complication rate (31% vs 10%; P = .004). During a median follow-up of 3 years, metastases developed at a higher rate in patients with giant PHEOs (45% vs 4% in referents; P < .0001). Disease-specific mortality was 7% in patients with giant PHEOs and 0% in referents (P = .02). Conclusion Patients with giant PHEOs compared to referents were more symptomatic, had a higher degree of catecholamine excess, and had a higher rate of perioperative complications. Almost half of patients with giant PHEOs developed metastases, warranting close follow-up.

Background: There is limited long-term follow-up of patients undergoing parathyroidectomy. Recurrence is described as 4% to 10%. This study evaluated persistence and recurrence of hypercalcemia in primary hyperparathyroidism after parathyroidectomy. Methods: Single-institution retrospective (1965–2010) population-based cohort from Olmsted County (MN) of patients undergoing surgery for primary hyperparathyroidism. Patients’ demographic data, preoperative and postoperative laboratory values, clinical characteristics, surgical treatment, and follow-up were noted. Results: A total of 345 patients were identified, 75.7% female, and median age 58.4 years [interquartile range (IQR): 17.6]. In all, 68% of patients were asymptomatic and the most common symptoms were musculoskeletal complaints (28.4%) and nephrolithiasis (25.6%). Preoperative median serum calcium was 11 mg/dL (IQR: 10.8–11.4 mg/dL), and median parathyroid hormone was 90 pg/mL (IQR: 61–169 pg/dL). Bilateral cervical exploration was performed in 38% and single gland resection in 79% of cases. Median postoperative serum calcium was 9.2 mg/dL (IQR: 5.5–11.3). Nine percent of patients presented persistence of hypercalcemia, and recurrence was found in 14% of patients. Highest postoperative median serum calcium was 10 mg/dL (IQR: 6–12.4), and median number of postoperative calcium measurements was 10 (IQR: 0–102). Postoperative hypercalcemia was identified in 37% of patient. Fifty-three percent were attributed to secondary causes, most commonly medications, 22%. Three percent of patients required treatment for postoperative hypercalcemia. Median time to recurrence and death were 12.2 and 16.7 years, respectively. Conclusion: Recurrent hypercalcemia after successful parathyroidectomy is higher than previously reported. Most cases are transient and often associated to other factors with only the minority requiring treatment. Long-term follow-up of serum calcium should be considered in patients after successful parathyroidectomy.

Abstract Objective Cystic adrenal mass is a rare imaging presentation of pheochromocytoma. We aimed to describe the clinical, biochemical and imaging characteristics of patients with cystic pheochromocytoma. Design Single‐centre, retrospective study, 2000−2020. Patients Consecutive patients with cystic pheochromocytoma were identified from our institutional pathology and adrenal tumour database. Results Of the 638 patients with pheochromocytomas, 21 (3.2%) had cystic pheochromocytomas (median age: 57 years, 57% women). Most pheochromocytomas were discovered incidentally (57%) or due to symptoms of catecholamine excess (24%). The median tumour size was 6.4 cm. On imaging, cystic pheochromocytomas were round or oval (90%), heterogeneous lesions (86%) with a thick solid rim (median rim thickness 13.9 mm, unenhanced computed tomography (CT) attenuation 40 Hounsfield units (HU), venous‐phase CT attenuation 83 HU), and a median cystic component of 40% (unenhanced CT attenuation 17.6 HU, venous‐phase CT attenuation 20.4 HU), and rarely with calcifications (15%). All 20 patients with biochemical testing had functioning tumours (adrenergic in 80%, noradrenergic in 20%). Total urinary metanephrine excretion correlated with the volume of the solid component ( R 2 = .75, p < .0001) but not the cystic component ( R 2 = .04, p = .4386). All patients underwent adrenalectomy (48% laparoscopic, 52% open), and the median duration of hospital stay was 4 days. Conclusions Cystic pheochromocytomas are rare, large tumours with a phenotypic appearance that can masquerade as other adrenal cystic lesions. The degree of biochemical abnormality in cystic pheochromocytomas is associated with the volume of the solid component. All patients with adrenal cysts that have a solid component or an unenhanced attenuation >10 HU should undergo biochemical testing for pheochromocytoma.

Background Until 2015, standard of care for low-risk papillary thyroid cancer (PTC) >1 cm was a total or near-total thyroidectomy. Despite changes in guidelines and surgical management of low-risk PTC since 2015, little data are available regarding the effect on the need for additional surgery or risk for development of lymph node metastases. Our aim was to determine outcomes in patients who underwent initial thyroid lobectomy for low-risk PTC at a high-volume tertiary care institution. Methods Retrospective review of patients ≥18 years old with biopsy proven low-risk PTC 1-4 cm who underwent partial thyroidectomy (eg, lobectomy/isthmusectomy) at Mayo Clinic, Rochester, MN, between March 2016 and June 30, 2019. Results From 1481 thyroidectomies performed during study period, 940 contained PTC on final pathology. Of these, 87 (of 123) patients who had an initial thyroid lobectomy met inclusion criteria. Five (6%) of these patients proceeded to completion thyroidectomy (CT), with 3 requiring CT and radioactive iodine in the first postoperative year and 2 undergoing only CT in the second postoperative year. No postoperative complications were reported. No patient in this cohort required additional surgery or treatment for newly discovered lymph node metastases during the follow-up period. 43 (of 72, 60%) patients not on thyroxine therapy preoperatively were started on thyroxine therapy postoperatively. Conclusions Early outcomes for those undergoing thyroid lobectomy for low-risk PTC at our institution have been favorable. These results support the 2015 American Thyroid Association guidelines to offer lobectomy for those with low-risk PTC 1-4 cm.

AbstractObjectiveTo describe the presentation and outcomes of patients with adrenal ganglioneuromas (AGNs).DesignSingle‐centre retrospective cohort study (1 January 1995 to 31 December 2019) and systematic review of literature (1 January 1980 to 19 November 2019).PatientsDiagnosed with histologically confirmed AGN.MeasurementsBaseline clinical, imaging and biochemical characteristics, recurrence rates and mortality. Subgroup analysis was performed on tumours with histologic elements of ganglioneuroma and pheochromocytoma (ie composite tumours).ResultsThe cohort study included 45 patients with AGN, 20 (44%) of which had composite tumours. Compared to pure AGN, patients with composite tumour were older (median age, 62.5 vs. 35 years, p < .001), had smaller tumours (median size, 3.9 vs. 5.7 cm, p = .016) and were discovered incidentally less frequently (65% vs. 84%, p = .009). No recurrences or ganglioneuroma‐specific mortality occurred during follow‐up (range, 0–266 months). The systematic review included 14 additional studies and 421 patients. The mean age of diagnosis was 39 years, and 47% were women. AGNs were discovered incidentally in 72% of patients, were predominantly unilateral (99%) and had a mean diameter of 5.8 cm and an unenhanced computed tomography (CT) attenuation of −118 to 49 Hounsfield units (HU). On imaging, 69% of AGNs were homogenous, 41% demonstrated calcifications, and 40% were lobulated.ConclusionsAGNs are rare benign tumours that present with variable imaging features including large size, unenhanced CT attenuation >20 HU, calcifications and lobulated shape. Imaging characteristics can assist in establishing a diagnosis and avoiding an unnecessary adrenalectomy. The association of pheochromocytomas with AGNs is frequent. Diagnosis should include biochemical testing.

Background In Jan 2018, we began routinely obtaining neck ultrasound (US) with 123I/99Tc-sestamibi (MIBI) for parathyroid gland localization and to identify thyroid pathology in the setting of primary hyperparathyroidism (1HPT). The aim of this study is to assess if routine neck US is a useful adjunct to 123I/99Tc-MIBI in 1HPT. Methods Patients undergoing surgery for 1HPT with both 123I/99Tc-MIBI and US at our institution after implementation of routine US were reviewed. Biopsy and surgical management of thyroid pathology was evaluated. 123I/99Tc-MIBI and US results were compared to intraoperative findings to determine sensitivity and positive predictive value (PPV) for parathyroid localization. Results From January 2018 to September 2019, there were 423 patients (mean, 61 years) that met inclusion criteria (80% women). Thyroid nodules were found on US in 57%, mean size 1.3 + 0.8 cm. Fine needle aspiration (FNA) was performed in 87 patients with nodules (36%). 35 patients (8.5%) required total or partial thyroidectomy for diagnoses/treatment. Papillary thyroid cancer (PTC) was found in 3.5% of the cohort with micro-PTC 53% and PTC 1-2 cm 40%. A successful parathyroid operation for 1HPT was achieved in 98.6% of patients. Positive predictive value for localization of abnormal parathyroid glands was 97% when US and 123I/99Tc-MIBI had concordant findings. Discussion Routine use of US in 1HPT commonly identifies nodules that are benign or low-risk PTC. Ultrasound is less sensitive for parathyroid localization but when used with 123I/99Tc-MIBI, concordant imaging has a high PPV.