Outcomes of Parathyroidectomy in Patients with Primary Hyperparathyroidism: A Systematic Review and Meta-analysis

Disparities in the treatment of primary hyperparathyroidism: A scoping review and conceptual model

BACKGROUND

Primary hyperparathyroidism is underdiagnosed and surgical treatment is underutilized and inequitably distributed. We present a review of the current literature on disparities in the treatment of hyperparathyroidism, with a focus on gaps in knowledge and paths forward.

METHODS

We searched PubMed and Scopus for abstracts related to disparities in hyperparathyroidism.

RESULTS

16 articles (of 1541) met inclusion criteria. The most commonly examined disparity was race. Notably, Black, Hispanic, and Asian patients were less likely to undergo surgery after diagnosis, face delays in obtaining treatment, and less likely to see a high-volume surgeon. Similar disparities in care were noted among those without insurance, older patients, and patients with limited English proficiency.

CONCLUSION

There are clear inequities in the treatment of hyperparathyroidism. Current research is in an early "identification" phase of disparities research; a new conceptual model based on established socioecological frameworks is provided to help move the field forward to "understanding" and "intervening" in surgical disparities.

Molecular imaging of thyroid and parathyroid diseases

INTRODUCTION

Molecular imaging of thyroid and parathyroid diseases has changed in recent years due to the introduction of new radiopharmaceuticals and new imaging techniques. Accordingly, we provided an clinicians-oriented overview of such techniques and their indications.

AREAS COVERED

A review of the literature was performed in the PubMed, Web of Science, and Scopus without time or language restrictions through the use of one or more fitting search criteria and terms as well as through screening of references in relevant selected papers. Literature up to and including December 2023 was included. Screening of titles/abstracts and removal of duplicates was performed and the full texts of the remaining potentially relevant articles were retrieved and reviewed.

EXPERT OPINION

Thyroid and parathyroid scintigraphy remains integral in patients with thyrotoxicosis, thyroid nodules, differentiated thyroid cancer and, respectively, hyperparathyroidism. In the last years positron-emission tomography with different tracers emerged as a more accurate alternative in evaluating indeterminate thyroid nodules [18F-fluorodeoxyglucose (FDG)], differentiated thyroid cancer [124I-iodide, 18F-tetrafluoroborate, 18F-FDG] and hyperparathyroidism [18F-fluorocholine]. Other PET tracers are useful in evaluating relapsing/advanced forms of medullary thyroid cancer (18F-FDOPA) and selecting patients with advanced follicular and medullary thyroid cancers for theranostic treatments (68Ga/177Ga-somatostatin analogues).

Normocalcemic primary hyperparathyroidism: From pathophysiology to clinical management

Normocalcemic primary hyperparathyroidism (NPHPT), a variant of primary hyperparathyroidism (PHPT) characterized by persistently elevated parathyroid hormone (PTH) levels and normal serum calcium, has gained recognition as a substantial subset of PHPT cases. Despite its increasing prevalence, the precise pathophysiology and natural progression of NPHPT remain enigmatic. This in-depth literature review explores recent advancements in our understanding of NPHPT, encompassing pathophysiology, clinical presentation, diagnostic approaches, medical and surgical management options. By synthesizing this wealth of information, this review aims to contribute to a more nuanced and informed approach to the treatment of patients grappling with NPHPT. As our understanding of the condition continues to evolve, the knowledge gathered from this review has the potential to significantly enhance the quality of care and outcomes for individuals afflicted with NPHPT, ultimately improving their overall well-being and prognosis.

Identification of novel risk factors for postoperative severe hypocalcemia in patients with primary hyperparathyroidism undergoing parathyroidectomy: a case control study

BACKGROUND

Patients with primary hyperparathyroidism (PHPT) are at risk for severe hypocalcemia (SH) following parathyroidectomy (PTX), but limited data exist on the predictors of SH. We aimed to identify risk factors for early postoperative SH after PTX in patients with PHPT and to evaluate the predictive value of clinical parameters.

METHODS

A retrospective review of patients with PHPT who underwent PTX between January 2010 and December 2022 was performed. A total of 46 patients were included in the study, with 15 (32.6%) experiencing postoperative SH, 19 (41.3%) having calculi in the ureter or kidney, and 37 (80.4%) having osteoporosis. Patients were divided into SH and non-SH groups based on postoperative serum calcium levels. Preoperative biochemical indicators, bone turnover markers, and renal function parameters were analyzed and correlated with postoperative SH.

RESULTS

Statistically significant (P < 0.05) differences were found in preoperative serum calcium (serum Ca), intact parathyroid hormone, serum phosphorus (serum P), serum Ca/P, percentage decrease of serum Ca, total procollagen type 1 intact N-terminal propeptide, osteocalcin (OC), and alkaline phosphatase levels between the two groups. Multivariate analysis showed that serum P (odds ratio [OR] = 0.989; 95% confidence interval [95% CI] = 0.981-0.996; P = 0.003), serum Ca (OR = 0.007; 95% CI = 0.001-0.415; P = 0.017), serum Ca/P (OR = 0.135; 95% CI = 0.019-0.947; P = 0.044) and OC levels (OR = 1.012; 95% CI = 1.001-1.024; P = 0.036) were predictors of early postoperative SH. The receiver operating characteristic curve analysis revealed that serum P (area under the curve [AUC] = 0.859, P < 0.001), serum Ca/P (AUC = 0.735, P = 0.010) and OC (AUC = 0.729, P = 0.013) had high sensitivity and specificity.

CONCLUSION

Preoperative serum P, serum Ca/P and osteocalcin levels may identify patients with PHPT at risk for early postoperative SH after PTX.

Nerve monitoring in endocrine surgery: Practice patterns differ among surgeons for parathyroidectomy and thyroidectomy

BACKGROUND

It is unknown whether intraoperative nerve monitoring is associated with reduced vocal cord dysfunction after parathyroidectomy. We aimed to investigate intraoperative nerve monitoring use among Collaborative Endocrine Surgery Quality Improvement Program surgeons and factors associated with vocal cord dysfunction after parathyroidectomy.

METHODS

Patients who underwent parathyroidectomy included in the Collaborative Endocrine Surgery Quality Improvement Program (2014-2022) were identified. The annual percent change in parathyroidectomies performed with intraoperative nerve monitoring was calculated using joinpoint regression. Multivariable logistic regression was used to compare outcomes between patients undergoing parathyroidectomy with/without intraoperative nerve monitoring. To compare surgeon-specific trends, Collaborative Endocrine Surgery Quality Improvement Program thyroidectomy and parathyroidectomy datasets (2014-2021) were combined. Parathyroidectomies performed by surgeons who used intraoperative nerve monitoring consistently in thyroidectomy were identified. Factors associated with intraoperative nerve monitoring were examined using multivariable logistic regression.

RESULTS

A total of 9,813 patients underwent parathyroidectomy. Intraoperative nerve monitoring was used in 49% of cases (n = 4,818). There was an increase in parathyroidectomies with intraoperative nerve monitoring from 2014 to 2018 (annual percent change 22.2, P = .01), followed by a plateau (2018-2022 annual percent change -0.66, P = .85). Few patients (0.44%, n = 43) developed vocal cord dysfunction. Vocal cord dysfunction was not associated with intraoperative nerve monitoring (adjusted odds ratio 0.92, P = .75). Whereas 41% (n = 56/138) of surgeons used intraoperative nerve monitoring routinely in parathyroidectomy, 65% (n = 90/138) used it routinely in thyroidectomy. Among surgeons who used intraoperative nerve monitoring routinely in thyroidectomy, only 57% used it routinely in parathyroidectomy; factors associated with intraoperative nerve monitoring during parathyroidectomy included reoperation (adjusted odds ratio 2.51, P < .01), secondary/tertiary hyperparathyroidism (adjusted odds ratio 1.42, P = .02), multiglandular disease (adjusted odds ratio 1.76, P < .001), and non-localized disease (adjusted odds ratio 1.65, P < .001).

CONCLUSION

Endocrine surgeons use intraoperative nerve monitoring selectively. Surgeons who routinely use intraoperative nerve monitoring during thyroidectomy are more likely to use it during parathyroidectomy. Future studies should determine who may benefit most from intraoperative nerve monitoring in parathyroidectomy.

Head-to-head comparison of [11C]methionine PET, [11C]choline PET, and 4-dimensional CT as second-line scans for detection of parathyroid adenomas in primary hyperparathyroidism

PURPOSE

Accurate preoperative localization is imperative to guide surgery in primary hyperparathyroidism (pHPT). It remains unclear which second-line imaging technique is most effective after negative first-line imaging. In this study, we compare the diagnostic effectiveness of [11C]methionine PET/CT, [11C]choline PET/CT, and four dimensional (4D)-CT head-to-head in patients with pHPT, to explore which of these imaging techniques to use as a second-line scan.

METHODS

We conducted a powered, prospective, blinded cohort study in patients with biochemically proven pHPT and prior negative or discordant first-line imaging consisting of ultrasonography and 99mTc-sestamibi. All patients underwent [11C]methionine PET/CT, [11C]choline PET/CT, and 4D-CT. At first, all scans were interpreted by a nuclear medicine physician, and a radiologist who were blinded from patient data and all imaging results. Next, a non-blinded scan reading was performed. The scan results were correlated with surgical and histopathological findings. Serum calcium values at least 6 months after surgery were used as gold standard for curation of HPT.

RESULTS

A total of 32 patients were included in the study. With blinded evaluation, [11C]choline PET/CT was positive in 28 patients (88%), [11C]methionine PET/CT in 23 (72%), and 4D-CT in 15 patients (47%), respectively. In total, 30 patients have undergone surgery and 32 parathyroid lesions were histologically confirmed as parathyroid adenomas. Based on the blinded evaluation, lesion-based sensitivity of [11C]choline PET/CT, [11C]methionine PET/CT, and 4D-CT was respectively 85%, 67%, and 39%. The sensitivity of [11C]choline PET/CT differed significantly from that of [11C]methionine PET/CT and 4D-CT (p = 0.031 and p < 0.0005, respectively).

CONCLUSION

In the setting of pHPT with negative first-line imaging, [11C]choline PET/CT is superior to [11C]methionine PET/CT and 4D-CT in localizing parathyroid adenomas, allowing correct localization in 85% of adenomas. Further studies are needed to determine cost-benefit and efficacy of these scans, including the timing of these scans as first- or second-line imaging techniques.

Outcomes of Surgical Management for Parathyroid Adenomas

Aim

Descriptive analysis of patients undergoing parathyroid adenoma surgery at a tertiary care hospital.

Methodology

Patients with parathyroid adenoma operated from January 2016 to December 2020. Serum calcium and PTH were used to establish the diagnosis. Ultrasonography (USG) studies localized the adenoma. NIH criteria was used for decision regarding surgery. Patients were analyzed with regards to pre operative localization, biochemical monitoring and other outcomes.

Results

Of the 15 eligible patients, all were symptomatic, with myalgia (34%) being the commonest symptom. Rome criteria confirmed the adequacy of the procedure by measuring intra operative drop in PTH. Average decrease in serum PTH level was 69.9% and serum calcium was 20.6% after excision of adenoma. The average size of excised adenoma was 2.5 cm. There were no post operative complications and all patients were normocalcemic on follow up.

Conclusion

Parathyroidectomy is a simple, safe and effective solution that reduces the morbidity of symptomatic primary hyperparathyroidism patients. Pre operative localization studies affirm the diagnosis and intra operative biochemical confirmation clinches the adequacy of resection.

Tissue Parathyroid Hormone Washout: A Reliable Method for the Localization and Exclusion of Parathyroid Adenomas

Background and objective Accurate identification of parathyroid adenoma (PA) is essential for minimally invasive treatment of primary hyperparathyroidism (PHPT). The aim of this study is to evaluate the results of parathyroid hormone (PTH) assay in aspirates of suspicious neck lesions and to clarify its reliability in determining whether the lesion is of parathyroid origin. Methods A total of 134 lesions (104 imaging-suspected PA and 30 concomitant thyroid nodules as a control group) of 101 patients were retrospectively analyzed. Patients with positive, negative, or never scintigraphy were included in our study. Ultrasound (US) was performed again and US-guided tissue fine needle aspiration with PTH washout (PTH-WO) was performed from suspicious lesions. A PTH-WO level higher than the patient's serum PTH levels is proposed for a positive test, and a PTH-WO level lower than the upper limit of the laboratory PTH level is proposed for a negative test. A definitive diagnosis was made postoperatively histopathologically. Results PTH-WO levels (median (IQR)) were significantly higher in the positive group (n = 93, 5000 (1600) ng/L) compared to the negative group (n = 11, 17 (13.1) ng/L) and thyroid nodule aspirate group (n = 30, 14 (4.3) ng/L) (p < 0.001). Among 93 PTH-WO-positive lesions, 42 lesions (45.1%) were not identified by parathyroid scintigraphy (PS), 20 (21.5%) lesions were suspiciously PS, and 33 lesions (35.4%) were negative or suspicious by first US findings. Of the 93 patients localized with PTH-WO, two were cystic PAs ablated by aspiration. The final pathology result of 91 operated patients proved PA. The sensitivity, specificity, negative predictive value, and positive predictive value of the PTH-WO were observed as 1.00, 0.82, 0.09, and 0.91, respectively. Conclusion Comprehensive repeated US and PTH-WO from the lesion increase the accurate localization of PAs. PTH-WO is a highly reliable method for differentiating parathyroid lesions from other cervical lesions.

18F-fluorocholine PET/MRI versus ultrasound and sestamibi for the localization of parathyroid adenomas

PURPOSE

Accurate preoperative localization is imperative to facilitate a minimally invasive parathyroidectomy (MIP) in primary hyperparathyroidism (pHPT). This study aims to compare the diagnostic value of standard-of-care localization techniques (ultrasound [US] and 99mTechnetium (99mTc) -sestamibi scintigraphy) to [F-18]-fluorocholine positron emission tomography/magnetic resonance imaging (FCH-PET/MRI) to determine the additional clinical usefulness of PET/MRI in a Canadian cohort.

METHODS

We conducted a prospective, appropriately powered, study to compare the diagnostic value of -FCH PET/MRI to that of the US and 99mTc-sestamibi scintigraphy for localization of parathyroid adenomas in a patient with pHPT. The primary outcome was the per-lesion sensitivity and positive predictive value (PPV) of FCH-PET/MRI, US, and 99mTc-sestamibi scintigraphy. Intraoperative surgeon localization, parathormone levels, and histopathological findings were used as reference standards.

RESULTS

Forty-one patients underwent FCH-PET/MRI of which 36 patients had parathyroidectomy. In these 36 patients, 41 parathyroid lesions were histologically confirmed as adenomas or hyperplastic glands. Per-lesion sensitivity of FCH-PET/MRI was 82.9% and of US and 99mTc-sestamibi scintigraphy combined at 50.0%, respectively. The sensitivity of FCH-PET/MRI was superior to that of US and 99mTc-sestamibi scintigraphy (p = 0.002). In the 19 patients in whom both US and 99mTc-sestamibi scintigraphy were negative, PET/MRI correctly identified the parathyroid adenoma in 13 patients (68%).

CONCLUSIONS

FCH-PET/MRI is a highly accurate imaging modality for localization of parathyroid adenomas in a tertiary center in North America. It is a superior functional imaging modality to 99mTc-sestamibi scintigraphy alone and more sensitive for localization of parathyroid lesions than US and 99mTc-sestamibi scintigraphy combined. This imaging modality could become the most valuable preoperative localization study given its superior performance in localizing parathyroid adenomas.

Update on the current management of persistent and recurrent primary hyperparathyroidism after parathyroidectomy

Primary hyperparathyroidism (pHPT) is the third most common endocrine disease. The surgical procedure aims for permanent cure, but recurrence has been reported in 4%-10% of pHPT patients. Preoperative localization imaging is highly valuable. It includes ultrasound, computed tomography (CT), single-photon-emission CT, sestamibi scintigraphy and magnetic resonance imaging. The operation has been defined as successful when postoperative continuous eucalcemia exists for more than the first six months. Ongoing hypercalcemia during this period is defined as persistence, and recurrence is defined as hypercalcemia after six months of normocalcemia. Vitamin D is a crucial factor for a good outcome. Intraoperative parathyroid hormone (PTH) monitoring can safely predict the outcomes and should be suggested. PTH ≤ 40 pg/mL or the traditional decrease ≥ 50% from baseline minimizes the likelihood of persistence. Risk factors for persistence are hyperplasia and normal parathyroid tissue on histopathology. Risk factors for recurrence are cardiac history, obesity, endoscopic approach and low-volume center (at least 31 cases/year). Cases with double adenomas or four-gland hyperplasia have a greater likelihood of persistence/ recurrence. A 6-mo calcium > 9.7 mg/dL and eucalcemic parathyroid hormone elevation at 6 mo may be associated with recurrence necessitating long-term follow-up. 18F-fluorocholine positron emission tomography and 4-dimensional CT in persistent and recurrent cases can be valuable before reoperation. With these novel advances in preoperative imaging and localization as well as intraoperative PTH measurement, the recurrence rate has dropped to 2.5%-5%. Six-month serum calcium ≥ 9.8 mg/dL and parathyroid hormone ≥ 80 pg/mL indicate a risk of recurrence. Negative sestamibi scintigraphy, diabetes and elevated osteocalcin levels are predictors of multiglandular disease, which brings an increased risk of persistence and recurrence. Bilateral neck exploration was considered the gold-standard diagnostic method. Minimally invasive parathyroidectomy and neck exploration are both effective surgical techniques. Multidisciplinary diagnostic and surgical management is required to prevent persistence and recurrence. Long-term follow-up, even up to 10 years, is necessary.

A 15-year experience: intraoperative parathyroid hormone assay for the management of primary hyperparathyroidism in a UK endocrine surgical unit

PURPOSE

This study aims to evaluate the outcomes of first-time parathyroidectomy for primary hyperparathyroidism using intraoperative PTH (IOPTH) assay in the light of the UK National Institute for Health and Care Excellence (NICE) guidelines for the management of primary hyperparathyroidism.

METHOD

This is a retrospective cohort analysis of a prospectively maintained database of endocrine surgery in a tertiary centre. Preoperative radiological localisation (concordance and accuracy), intraoperative PTH parameters and adjusted serum calcium at minimum 6-month follow-up were analysed. The accuracy of IOPTH to predict post-operative normocalcaemia and the number needed to treat (NNT) within the cohort when IOPTH was utilised were determined. Differences between groups were evaluated with Chi-squared and Fisher's exact test.

RESULTS

Between January 2004 and September 2018, 849 patients (75.4% women), median age 64 years (IQR 54-72), were analysed. The median preoperative adjusted serum calcium was 2.80mmol/l (IQR 2.78-2.90), and the median preoperative PTH was 14.20pmol/l (IQR 10.70-20.25). The overall first-time cure (normocalcaemia) rate was 96.4%. The sensitivity, specificity, positive predictive value and negative predictive values of IOPTH were 96.8%, 83.2%, 97.6% and 78.8%, respectively, with an accuracy of 95.1%. For patients with concordant scans (48.3%), a targeted approach without IOPTH would have achieved a cure rate of 94.1% compared with 98.0% using IOPTH (p<0.01) CONCLUSION: The use of IOPTH assay significantly improved the rate of normocalcaemia at 6 months. The low NNT to benefit from IOPTH, particularly those patients with a single positive scan, and the inevitable reduction in the potential costs incurred from failure and reoperation justify its utilisation.

Parathyroidectomy for adults with primary hyperparathyroidism

BACKGROUND

Primary hyperparathyroidism (PHPT), a disorder in which the parathyroid glands produce excessive amounts of parathyroid hormone, is most common in older adults and postmenopausal women. While most people with PHPT are asymptomatic at diagnosis, symptomatic disease can lead to hypercalcaemia, osteoporosis, renal stones, cardiovascular abnormalities and reduced quality of life. Surgical removal of abnormal parathyroid tissue (parathyroidectomy) is the only established treatment for adults with symptomatic PHPT to prevent exacerbation of symptoms and to be cured of PHPT. However, the benefits and risks of parathyroidectomy compared to simple observation or medical therapy for asymptomatic and mild PHPT are not well established.

OBJECTIVES

To evaluate the benefits and harms of parathyroidectomy in adults with PHPT compared to simple observation or medical therapy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, LILACS, ClinicalTrials.gov and WHO ICTRP from their date of inception until 26 November 2021. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing parathyroidectomy with simple observation or medical therapy for the treatment of adults with PHPT.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. cure of PHPT, 2. morbidity related to PHPT and 3. serious adverse events. Our secondary outcomes were 1. all-cause mortality, 2. health-related quality of life and 3. hospitalisation for hypercalcaemia, acute renal impairment or pancreatitis. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We identified eight eligible RCTs that included 447 adults with (mostly asymptomatic) PHPT; 223 participants were randomised to parathyroidectomy. Follow-up duration varied from six months to 24 months. Of the 223 participants (37 men) randomised to surgery, 164 were included in the analyses, of whom 163 were cured at six to 24 months (overall cure rate 99%). Parathyroidectomy compared to observation probably results in a large increase in cure rate at six to 24 months follow-up: 163/164 participants (99.4%) in the parathyroidectomy group and 0/169 participants in the observation or medical therapy group were cured of their PHPT (8 studies, 333 participants; moderate certainty).  No studies explicitly reported intervention effects on morbidities related to PHPT, such as osteoporosis, osteopenia, kidney dysfunction, urolithiasis, cognitive dysfunction or cardiovascular disease, although some studies reported surrogate outcomes for osteoporosis and cardiovascular disease. A post-hoc analysis revealed that parathyroidectomy, compared to observation or medical therapy, may have little or no effect after one to two years on bone mineral density (BMD) at the lumbar spine (mean difference (MD) 0.03 g/cm2,95% CI -0.05 to 0.12; 5 studies, 287 participants; very low certainty). Similarly, compared to observation, parathyroidectomy may have little or no effect on femoral neck BMD after one to two years (MD -0.01 g/cm2, 95% CI -0.13 to 0.11; 3 studies, 216 participants; very low certainty). However, the evidence is very uncertain for both BMD outcomes. Furthermore, the evidence is very uncertain about the effect of parathyroidectomy on improving left ventricular ejection fraction (MD -2.38%, 95% CI -4.77 to 0.01; 3 studies, 121 participants; very low certainty). Four studies reported serious adverse events. Three of these reported zero events in both the intervention and control groups; consequently, we were unable to include data from these three studies in the pooled analysis. The evidence suggests that parathyroidectomy compared to observation may have little or no effect on serious adverse events (RR 3.35, 95% CI 0.14 to 78.60; 4 studies, 168 participants; low certainty).  Only two studies reported all-cause mortality. One study could not be included in the pooled analysis as zero events were observed in both the intervention and control groups. Parathyroidectomy compared to observation may have little or no effect on all-cause mortality, but the evidence is very uncertain (RR 2.11, 95% CI 0.20 to 22.60; 2 studies, 133 participants; very low certainty). Three studies measured health-related quality of life using the 36-Item Short Form Health Survey (SF-36) and reported inconsistent differences in scores for different domains of the questionnaire between parathyroidectomy and observation. Six studies reported hospitalisations for the correction of hypercalcaemia. Two studies reported zero events in both the intervention and control groups and could not be included in the pooled analysis. Parathyroidectomy, compared to observation, may have little or no effect on hospitalisation for hypercalcaemia (RR 0.91, 95% CI 0.20 to 4.25; 6 studies, 287 participants; low certainty). There were no reported hospitalisations for renal impairment or pancreatitis.

AUTHORS' CONCLUSIONS

In accordance with the literature, our review findings suggest that parathyroidectomy, compared to simple observation or medical (etidronate) therapy, probably results in a large increase in cure rates of PHPT (with normalisation of serum calcium and parathyroid hormone levels to laboratory reference values). Parathyroidectomy, compared with observation, may have little or no effect on serious adverse events or hospitalisation for hypercalcaemia, and the evidence is very uncertain about the effect of parathyroidectomy on other short-term outcomes, such as BMD, all-cause mortality and quality of life. The high uncertainty of evidence limits the applicability of our findings to clinical practice; indeed, this systematic review provides no new insights with regard to treatment decisions for people with (asymptomatic) PHPT. In addition, the methodological limitations of the included studies, and the characteristics of the study populations (mainly comprising white women with asymptomatic PHPT), warrant caution when extrapolating the results to other populations with PHPT. Large-scale multi-national, multi-ethnic and long-term RCTs are needed to explore the potential short- and long-term benefits of parathyroidectomy compared to non-surgical treatment options with regard to osteoporosis or osteopenia, urolithiasis, hospitalisation for acute kidney injury, cardiovascular disease and quality of life.

Comparative utility of preoperative imaging in normocalcemic versus hypercalcemic primary hyperparathyroidism

BACKGROUND

Normocalcemic primary hyperparathyroidism (PHPT) has been shown to benefit from parathyroidectomy. PHPT may be localized preoperatively with various imaging modalities, but the utility of preoperative imaging in normocalcemic PHPT compared to hypercalcemic PHPT is not well defined.

METHODS

Retrospective review was performed on all PHPT patients who underwent parathyroidectomy from 2001 to 2019. Patients were stratified into normocalcemic and hypercalcemic groups. Patient and outcomes data were analyzed.

RESULTS

All 2218 patients in this database were included. 433 patients had normocalcemic PHPT (19.5%) and 1785 had hypercalcemic PHPT (80.5%). Among normocalcemic patients, equivalent cure rates were seen between patients with preoperative imaging versus those without (100% vs 99%). No differences in postoperative complications were demonstrated except for a slightly increase in transient hypocalcemia in patients without imaging.

CONCLUSIONS

Normocalcemic PHPT patients had equivalent cure and similar complication rates with or without preoperative imaging compared to hypercalcemic patients. Routine localization studies in normocalcemic PHPT may be safely omitted in favor of exploration with intraoperative adjuncts by experienced surgeons.

Surgery for primary hyperparathyroidism

Primary hyperparathyroidism (PHPT) is a hypercalcemic disorder that occurs when one or more parathyroid glands produces excessive parathyroid hormone (PTH). PHPT is typically treated with surgery, and it remains the only definitive therapy, whose techniques have evolved over previous decades. Advances in preoperative localization exams and the intraoperative PTH monitoring have become the cornerstones of recent parathyroidectomy techniques, as minimally invasive techniques are appropriate for most patients. Nevertheless, these techniques, are not suitable for PHPT patients who are at risk for multiglandular disease, especially in those who present with familial forms of PHPT that require bilateral neck exploration. This manuscript also explores other conditions that warrant special consideration during surgical treatment for PHPT: normocalcemic primary hyperparathyroidism, pregnancy, reoperation for persistent or recurrent PHPT, parathyroid carcinoma, and familial and genetic forms of hyperparathyroidism.

The value of intraoperative parathyroid hormone monitoring in patients with primary hyperparathyroidism and varying baseline parathyroid hormone levels

BACKGROUND

When applying intraoperative parathyroid hormone monitoring (IOPTH) to patients with primary hyperparathyroidism (PHPT), there are established criteria predicting biochemical cure in patients with basal parathyroid hormone (PTH) levels in the medium range (100-400 pg/ml); however, there is a challenge concerning patients with low (less than 100 pg/ml) or high (more than 400 pg/ml) basal PTH levels. The aim of this study was to investigate the value of the 'Vienna criterion' applied during IOPTH in patients with PHPT and various basal PTH concentrations.

METHODS

Consecutive patients between 1999-2009 with a biochemical diagnosis of PHPT who underwent surgical parathyroidectomy were included. Based on preoperative PTH levels they were divided into three groups: group 1 (low) (<100 pg/ml), group 2 (medium) (100-400 pg/ml) and group 3 (high) (>400 pg/ml) basal PTH. PTH was measured at the start of the operation, when the gland was excised and then at 5, 10 and 15 min after. Calcium and PTH levels were measured at 7 days and 12 months postoperatively. Sensitivity, specificity, positive and negative predictive value, as well as accuracy of IOPTH were calculated for the different groups postoperatively.

RESULTS

675 patients with PHPT were analysed. Sensitivity and specificity were 83.7 per cent and 66.7 per cent in group 1 (n = 187), 90.7 per cent and 69.2 per cent in group 2 (n = 433), and 94.4 per cent and 100 per cent in group 3 (n = 55) to predict cure. Preoperative creatinine (p = 0.002) showed significant statistical difference between the groups but was not related to intraoperative PTH decline. At 12 months follow-up normocalcaemia was documented in 98.9 per cent in group 1, 99.0 per cent group 2, and 98.0 per cent of group 3 patients.

CONCLUSION

Normocalcaemia was predicted intraoperatively by applying the 'Vienna criterion' in 98 to 100 per cent and was confirmed after 12 months follow-up in up to 99.0 per cent of patients. Low specificity and a high false-negative rate in patients with low basal PTH show that other criteria might be better suited for this group.

Readability and Quality of Online Health Information Regarding Parathyroidectomy

Objective

Assessment of the readability and quality of online health information regarding parathyroidectomy.

Study Design

Cross-sectional analysis.

Setting

Websites providing patient-oriented health information regarding parathyroidectomy obtained via the Google search engine.

Methods

The top 75 Google search results for “parathyroidectomy,”“parathyroid surgery,” and “parathyroid gland removal” were reviewed. Websites were categorized by website type and country of origin. Readability was assessed by Flesch-Kincaid Grade Level and Simple Measure of Gobbledygook. Website quality was assessed per JAMA benchmark criteria and the DISCERN instrument.

Results

A total of 74 unique websites were evaluated. The mean readability of the assessed websites exceeded the recommended sixth-grade reading level on the Flesch-Kincaid Grade Level and Simple Measure of Gobbledygook (P < .001). Readability did not vary significantly by website type. Websites originating from the United Kingdom were significantly more readable than those from the United States. The majority of assessed websites were of poor quality (n = 42, 56.8%) on assessment based on the DISCERN instrument. Quality varied significantly by website category on the JAMA benchmark criteria (P < .001) and DISCERN score (P = .049) with commercial websites receiving the highest scores. DISCERN score also varied significantly by country of origin (P = .036) with UK sites receiving highest mean DISCERN scores.

Conclusion

Online health information regarding parathyroidectomy is largely of poor quality and is poorly readable for many patients. Institutions utilizing well-defined guidelines for development of patient educational resources may provide online health information of greater quality and readability.

Long-term outcome of surgical techniques for sporadic primary hyperparathyroidism in a tertiary referral center in Belgium

PURPOSE

Surgery remains the only permanent treatment option for primary hyperparathyroidism (pHPT). To date, the number of long-term outcome studies of parathyroidectomy is limited. This study aims to compare different surgical approaches and evaluate the importance of preoperative localization imaging in the treatment of pHPT.

METHODS

All 200 consecutive patients with a parathyroidectomy for sporadic pHPT without planned concomitant surgery between 09/2009 and 04/2021 in a Belgian tertiary referral hospital were enrolled. All patients underwent at least two preoperative localization imaging studies (neck ultrasound, CT, SPECT, and/or Sestamibi scintigraphy) of the parathyroid glands. The main outcomes were the (long-term) cured proportion and postoperative morbidity (hypocalcemia, recurrent laryngeal nerve palsy, return to theater for bleeding, and wound morbidity).

RESULTS

Most patients were referred with concordant positive imaging (82%, n = 164). Only nine patients (4.5%) had double negative imaging, not revealing a possible adenoma. The remaining 27 (13.5%) were referred with discordant imaging. Parathyroidectomy was performed via traditional cervicotomy (30%), mini-open approach (39.5%), or endoscopic approach (30.5%). Morbidity was low with no persistent hypocalcemia, one return to theater for bleeding, and no 30-day mortality. In the concordant imaging population, 13 patients (8%) had multiglandular disease. Overall, 97.5% was considered cured. Long-term recurrence was 12% with a minimal follow-up of 5 years.

CONCLUSION

This consecutive, single-surgeon, single-center cohort with extensive data collection and long-term follow-up confirms the safety and excellent cured proportions of minimally invasive parathyroidectomy. Disease recurrence becomes more important long after surgery.

Efficacy and safety of radiofrequency ablation for primary and secondary hyperparathyroidism with or without previous parathyroidectomy: a retrospective study

INTRODUCTION

This study aimed to investigate and compare the therapeutic efficacy and safety of ultrasound-guided radiofrequency ablation (RFA), between primary hyperparathyroidism (PHPT) and secondary hyperparathyroidism (SHPT) patients, with or without previous parathyroidectomy (PTX).

SUBJECTS AND METHODS

A total of 21 patients (7 PHPT, 14 SHPT) underwent RFA for hyperparathyroidism (HPT) at Kaohsiung Chang Gung Memorial Hospital, Taiwan. Five of the 14 SHPT patients had previously received PTX. The laboratory data, volume change of each parathyroid nodule, symptomatic scores, and complications were analyzed and compared between all groups at 1 and 7 days, and at 1, 3, 6, and 12 months after RFA.

RESULTS

After RFA, the volume reduction ratio (VRR) for all patients at the last follow-up was 93.76%, and clinical symptoms significantly improved. At 12 months, all PHPT patients achieved successful treatment of intact PTH (iPTH). In SHPT patients, the mean iPTH value significantly decreased 1-day post-RFA, subsequently exhibiting a transient rebound which proceeded to decrease, with 57.1% reaching successful treatment standards. SHPT patients with PTX showed a lower complication score, shorter ablation time, higher iPTH baseline and outcomes, and lower VRR, compared to patients without PTX. The serum calcium level significantly decreased to normal range in 85.7% of all patients at 12 months. Severe hypocalcemia occurred in 23.8% at 1 week, and all were corrected with calcium supplements.

CONCLUSIONS

RFA demonstrates a therapeutic efficacy similar to PTX. It can thus be considered an effective alternative treatment for PHPT, SHPT, or post-PTX patients who are unsuitable for another PTX.

The efficacy and safety of cinacalcet in primary hyperparathyroidism: a systematic review and meta-analysis of randomized controlled trials and cohort studies

Cinacalcet, a positive allosteric modulator of the calcium sensing receptor (CaSR) reduces parathyroid hormone (PTH) secretion by increasing the sensitivity of the CaSR on parathyroid cells. We conducted a systematic review and meta-analysis on the safety and efficacy of cinacalcet in Primary Hyperparathyroidism (PHPT). MEDLINE, Embase, BIOSIS, and the Cochrane Library were searched for published articles (from database inception to Sept 2020). All double-blind RCTs and cohort studies that reported data on the efficacy and safety of cinacalcet therapy in individuals ≥ 18 with PHPT were included. Random effect meta-analysis was performed to estimate the efficacy of cinacalcet in lowering serum calcium and PTH levels compared with placebo. 4 RCTs (177 participants) and 17 cohort studies (763 participants) were eligible for final analysis. Pooled results from the RCTs suggest that, when compared to placebo and administered for up to 28 weeks, cinacalcet normalizes serum calcium (≤ 10.3 mg/dl) in patients with PHPT [RR 20 (95% CI 6.04 - 68.52, I² = 0%, p_{heterogeneity} < 0·00001)]. Serum PTH levels decreased significantly after 2 weeks and up to 28 weeks after treatment with cinacalcet. In the pooled analysis of the 17 cohort studies, serum calcium levels normalized in 76% (95% CI 66% to 86%; I² = 92%, p_{heterogeneity} < 0·00001) of patients regardless of the duration of treatment. In most studies, PTH levels decreased by 13% to 55%. No RCT reported on BMD as a primary or secondary outcome, and no improvement in BMD was noted in the 2 non-randomized studies that reported densitometric findings. No significant difference in urinary calcium was noted with cinacalcet therapy in either the RCTs or non-randomized studies. There was no significant difference in overall adverse events (AE) (RD 0.01, 95% CI -0.07 to 0.26) compared to placebo noted in the RCTs. In the non-randomized studies, pooled weighted AE rate was 45% (95% CI 32 to 59%). Risk of bias was low in 2/4 RCTs and 6/17cohort studies; risk was intermediate in 2/4 RCTs and 8/17 cohort studies, and risk was high in 3/17 cohort studies. In PHPT, cinacalcet lowers serum calcium and PTH with greater effects on calcium than on PTH in the short term. In the doses reported, the drug is safe with tolerable side effects. These findings can help inform targeted medical therapy of PHPT in those for whom lowering the serum calcium is indicated and for whom parathyroidectomy is not an option.

Long-term Cure of Primary Hyperparathyroidism After Scan-Directed Parathyroidectomy: Outcomes From A UK Endocrine Surgery Unit

BACKGROUND

Two-decades ago, the advent of sestamibi scintigraphy led to an enthusiastic acceptance of minimally invasive parathyroidectomy (MIP) in most surgical centres. More recently, concerns have been raised about the efficacy of limited neck exploration and some surgeons proposed bilateral neck exploration to be (once again) the gold standard operation for primary hyperparathyroidism in 2020s.

METHODS

A departmental database was used to identify patients who had MIP after concordant dual localisation with sestamibi scintigraphy and ultrasound scans. Long-term follow-up data were obtained from electronic patient records to ascertain any further treatment for recurrent disease and confirm most recent biochemical status. Patients with negative localisation scans and those with familial disease were excluded from analysis.

RESULTS

Between June 2001 and August 2014 a total of 404 patients (108 M:296F, median age 63 years, range 17-90 years) underwent MIP and had normalisation of calcium in first 6 weeks after the operation. Information on electronic patient records were missing in 14 patients; therefore, data on 390 patients were analysed. During median follow-up of 78 months (IQR: 21.25-111.75 months), 375 patients had normocalcaemia (2.36 mmol/L, IQR: 2.29-2.44 mmol/L) at a median 75 months, (IQR: 20-118 months) after their operation. Overall, 15 (3.85%) patients had biochemical evidence of recurrent disease (2.70 mmol/L IQR: 2.63-2.75 mmol/L) at 92 months (Range: 6-196) after initial operation. Of these, 5 (1.28%) patients underwent a second parathyroid procedure.

CONCLUSION

Recurrence after scan-directed unilateral neck exploration occurred in 4% of patients after a long disease-free interval. Only one patient had recurrent disease within 1-year of primary surgery. The data suggest that bilateral neck exploration at the time of initial operation, in this selected cohort, is unlikely to have uncovered multi-gland disease and prevent disease recurrence. Focused parathyroidectomy in patients with convincing localisation studies should continue.

Sporadic Primary Hyperparathyroidism

Sporadic primary hyperparathyroidism is a common endocrinopathy, particularly afflicting postmenopausal women and both African American men and women. Although classic signs and symptoms of the disease are well appreciated and described, because of the ease and availability and low threshold for screening, the disorder often is diagnosed in patients who are minimally symptomatic or asymptomatic. Surgery conducted by experienced endocrine surgeons has a high cure rate, particularly if guided by concordant imaging. In patients who cannot safely undergo surgery or who fail to be cured, medical therapy with the oral calcimimetic cinacalcet is a validated option for controlling serum calcium levels.

Evaluation and Management of Elevated Parathyroid Hormone Levels in Normocalcemic Patients

Primary hyperparathyroidism is a common endocrine disorder. It used to present as a highly symptomatic disease before the advent of the multichannel autoanalyzer, now usually presenting as mild asymptomatic hypercalcemia. A newer presentation has been increasingly identified in the past two decades, normocalcemic primary hyperparathyroidism, presenting with elevated parathyroid hormone concentrations and consistently normal serum calcium. These patients are usually symptomatic, with parathyroid hormone levels measured in the evaluation for kidney stones or osteoporosis. It is important to exclude causes of secondary hyperparathyroidism. This review will focus on the evaluation and management of elevated parathyroid hormone levels in normocalcemic patients.

Head-to-head comparison among 18F-choline PET/CT, 4D contrast-enhanced CT, and 18F-choline PET/4D contrast-enhanced CT in the detection of hyperfunctioning parathyroid glands: a systematic review and meta-analysis

INTRODUCTION

In primary hyperparathyroidism (PHPT), the localization of hyperfunctioning parathyroid gland (HPTG) allows tailored surgery. Although Four-Dimensional Contrast-enhanced Computed Tomography (4DCeCT) and ¹⁸F-choline Positron Emission Tomography/Computed Tomography (PET/CT) are reported to be promising second-line imaging procedures, no meta-analysis of their comparison exists.

DESIGN

we conducted a systematic review and meta-analysis to find original papers reporting the head-to-head comparison of 4DCeCT, ¹⁸F-choline PET/CT and integrated ¹⁸F-choline-PET/4DCeCT.

METHODS

this systematic review was conducted according to PRISMA. PubMed, CENTRAL, Scopus, and Web of Science were searched until January 2021. Studies comparing the ability of 4DCeCT, ¹⁸F-choline PET/CT and ¹⁸F-choline PET/4DCeCT to identify HPTG in patients with PHPT were selected. A per patient-based analysis of the three procedures was conducted in all patients (detection rate, DR) and in those with histologically confirmed HPTG (sensitivity).

RESULTS

Of the 78 records identified, five articles (153 PHPT patients) published between January the 1st, 2018 and January the 31st, 2021 were included. The pooled DR of ¹⁸F-choline PET/CT, 4DCeCT and ¹⁸F-choline PET/4DCeCT was 0.86, 0.69, and 0.86, respectively, while their pooled sensitivity was 0.89, 0.77 and 0.93, respectively. The analysis of pooled discrepancy showed that the sensitivity of ¹⁸F-choline PET/CT and ¹⁸F-choline PET/4DCeCT was higher than that of 4DCeCT by 0.11 and 0.13, respectively, the sensitivity of ¹⁸F-choline PET/4DCeCT being 0.06 higher than that of ¹⁸F-Choline PET/CT.

CONCLUSIONS

This meta-analysis suggests that the sensitivity of ¹⁸F-choline PET/CT and ¹⁸F-choline PET/4DCeCT is higher than that of 4DCeCT, while only a slight difference was observed between ¹⁸F-choline PET/CT and ¹⁸F-choline PET/4DCeCT.

Safety of parathyroidectomy in older vs. younger patients with primary hyperparathyroidism

BACKGROUND

Primary hyperparathyroidism is a prevalent endocrinopathy for which surgery is the only curative option. Parathyroidectomy is primarily recommended in younger and symptomatic patients, while there are still concerns regarding surgical complications in older patients. We therefore assessed the association of age with surgical outcomes in patients undergoing parathyroidectomy in a large population in Switzerland.

METHODS

Population-based cohort study of adult patients with primary hyperparathyroidism undergoing parathyroidectomy in Switzerland between 2012 and 2018. The cohort was divided into four age groups (<50 years, 50-64 years, 65-74 years, ≥75 years). The primary outcome was a composite of in-hospital postoperative complications. Secondary outcomes were intensive care unit (ICU) admission, unplanned 30-day-readmission, and prolonged length of hospital stay.

RESULTS

We studied 2642 patients with a median (IQR) age of 62 (53-71) years. Overall, 111 patients had complications including surgical re-intervention, hypocalcemia, and vocal cord paresis. As compared to <50 year-old patients, older patients had no increased risk for in-hospital complications after surgery (50-64 years: odds ratio (OR): 0.51 (95% CI, 0.28 to 0.92); 65-74 years: OR: 0.72 (95% CI, 0.39 to 1.33); ≥75 years: OR: 1.03 (95% CI, 0.54 to 1.95), respectively. There was also no association of age and rates of ICU-admission and unplanned 30-day-readmission, but oldest patients had longer hospital stays (OR: 2.38 (95% CI, 1.57 to 3.60)).

CONCLUSION

≥50 year-old patients undergoing parathyroidectomy had comparable risk of in-hospital complications as compared with younger ones. These data support parathyroidectomy in even older patients with primary hyperparathyroidism as performed in clinical routine.

Water clear cell ectopic non-iatrogenic giant parathyroid adenoma in sternohyoid muscle with thyroid nodule and asymptomatic hypercalcemia due to primary hyperparathyroidism: Case report and literature review

Background

Ectopic parathyroid gland is not uncommon, and is associated with primary hyperparathyroidism. Giant parathyroid adenoma (PA) and concurrent presence of enlarged thyroid nodule increases the probability of ectopic location. The combination of a giant PA that is ectopic (within the strap muscle) in the neck is very rare, especially in cases with no previous surgery. The rare histopathological findings of the current case, water clear cell parathyroid adenoma (WCCPA), could explain the patient's presentation, since it has low endocrine function.

Case presentation

A 56-year-old Qatari female on routine visit to primary health care physician for hypertension, was incidentally discovered to be hypercalcemic and was referred to the emergency department of our institution. Neck ultrasound showed a thyroid nodule on the left side, but ^99mTc-sestamibi scintigraphy identified a left PA. FNAC of the thyroid nodule showed that it was a colloid nodule. She underwent left hemithyroidectomy and excision of left PA. Intraoperatively, the PA was giant and in the sternohyoid muscle. Intraoperative monitoring of intact PTH (IOiPTH) confirmed successful excision.

Discussion

Ectopic giant parathyroid adenoma is rare especially with the intramuscular location in sternohyoid muscle in the neck without previous neck surgeries. The presence of thyroid nodule could be a precipitating factor for migration of the PA. Preoperative assessment with the radiological image is crucial for diagnosis but sometimes fail to localized the PA.

Conclusion

Giant asymptomatic PA with long standing low function before hyperfunctioning should raise the suspicion of WCCPA. If diagnosis is confirmed, metastasis from a clear cell renal cell carcinoma should be ruled out.

•

We report a unique rare case of non-iatrogenic ectopic giant water clear cell parathyroid adenoma (WCCPA)

•

A parathyroid adenoma >3.5 gm, asymptomatic and with low function before hyperfunctioning, should raise suspicion of WCCPA.

•

History, examination, ultrasound, sesta-MIBI scintigraphy and immunohistochemical studies are important for diagnosis.

•

High preoperative parathyroid hormone and calcium need monitoring in post-operative period to avoid hypocalcemia.

Morbidity following thyroid and parathyroid surgery: Results from key performance indicator assessment at a high-volume centre in New Zealand

BACKGROUND

Complications following thyroid/parathyroid surgery include recurrent laryngeal nerve (RLN) injury, hypocalcaemia and return to theatre for haematoma evacuation. Rates of these form the basis of key performance indicators (KPI). An endocrine database, containing results from 1997, was established at the North Shore Hospital in Auckland, New Zealand. We aimed to measure complication rates by procedure (thyroid and parathyroid), explore a temporal change in our unit and compare our results against international literature.

METHODS

A retrospective review of the database between July 1997 and February 2020 was performed. The results for each KPI were analysed in total and over consecutive time periods. A review of the literature was carried out to find international complication rates for comparison. A cumulative sum (CUSUM) analysis was performed to give visual feedback on performance.

RESULTS

There were 1062 thyroidectomies and 336 parathyroidectomies from July 1997 to February 2020. Thyroid surgery results found rates of temporary/permanent RLN injury of 1.9%/0.3%, temporary/permanent hypocalcaemia of 22.3/2.5%, and return to theatre for haematoma evacuation of 1.1%. Parathyroid surgery results were, temporary RLN injury of 0.8% (no permanent injury), temporary/permanent hypocalcaemia of 1.7%/0.4%, and return to theatre for haematoma evacuation of 0.3%. CUSUM analysis found KPI results to be comparable with international literature.

CONCLUSION

Our unit's KPI results are comparable to published results in the literature. The use of this clinical database will help in future monitoring of performance and help drive improvement in the service. Embedding prospective data collection as routine practice allows for continuous improvement for the unit.

Effectiveness and Safety of Thermal Ablation in the Treatment of Primary Hyperparathyroidism: A Multicenter Study

CONTEXT

Ultrasound (US)-guided thermal ablation has generated recent interest as minimally invasive treatments of primary hyperparathyroidism (pHPT). But definitive evidence for the efficacy of thermal ablation in treating pHPT is not well characterized.

OBJECTIVE

This work aims to evaluate the effectiveness and safety of thermal ablation for pHPT.

METHODS

From January 2015 to March 2020, data pertaining to patients who received thermal ablation for pHPT at 4 centers were retrospectively analyzed. The median follow-up duration was 18.1 months (interquartile range, 6.5-42.2 months). A cure referred to the reestablishment of normal values of serum calcium and intact parathyroid hormone throughout the entire follow-up period, at least more than 6 months. The technical success, effectiveness, and safety of treatment were analyzed.

RESULTS

A total of 119 patients (mean age, 57.2 ± 16.3 years; 81 female) with 134 parathyroid nodules were enrolled. The mean maximum diameter of the parathyroid glands was 1.6 ± 0.9 cm. Ninety-six patients underwent microwave ablation (MWA), and 23 patients underwent radiofrequency ablation (RFA). The technical success rate was 98.3% and the cure rate was 89.9%. Significant differences were found in the maximum diameter between the cured patients and the patients who did not undergo ablation of the target lesions. Except for cases with pHPT nodules less than 0.6 cm in diameter, the cure rate was 95%. There were no difference in cure rates at 6 months between the MWA and RFA groups (MWA vs RFA, 90.6% vs 87.0%; χ 2 = 0.275, P = .699). The volume reduction rate of the ablation zone was 94.6% at 12 months. The complication rate was 6.7% (8/119). With the exception of one patient with persistent voice impairment, other symptoms spontaneously resolved within 6 months.

CONCLUSION

Thermal ablation is effective and safe for pHPT.

Microwave ablation versus radiofrequency ablation for primary hyperparathyroidism: a multicenter retrospective study

OBJECTIVE

To compare the clinical outcomes of microwave ablation (MWA) and radiofrequency ablation (RFA) in the treatment of primary hyperparathyroidism (pHPT).

METHOD

This retrospective study included 104 pHPT patients treated by MWA or RFA between January 2015 and March 2020 in four centers. The clinical outcomes including effectiveness and complications were compared between the two groups. Ablation cure was defined as the reestablishment of normal values of serum calcium and intact parathyroid hormone (iPTH) at least more than 6 months. Clinical cure was defined as the reestablishment of normal values of serum calcium and iPTH throughout the entire follow-up period.

RESULTS

A total of 77 patients underwent MWA (mean age, 55.5 ± 16.4 years) and 27 underwent RFA (mean age, 58.9 ± 15.6 years). During the follow-up (median, 18.7 months in the MWA group; 12 months in the RFA group), no difference was observed between ablation cure rates (88.3% vs. 88.9%, p = 1.000), clinical cure rates (87.0% vs. 82.3%, p = .880), recurrent pHPT (5.2% vs. 3.7%, p = .447), persistent pHPT (11.7% vs. 11.1%, p = 1.000) and complication rate (9.1% vs. 3.7%, p = .677). A maximum diameter less than 0.7 cm was an independent prognostic factor of uncured pHPT in ablation (hazard ratio, 0.1; 95% confidence interval: 0.02, 0.54; p = .007). Major complication - voice change encountered in five patients (6.5%) in the MWA group and in one patient (3.7%) in the RFA group.

CONCLUSION

Both RFA and MWA are safe and effective techniques for patients with pHPT, with comparable clinical outcomes.

Ambidirectional cohort study on the agreement of ultrasonography and surgery in the identification of parathyroid pathology, and predictors of postoperative hypocalcemia in 47 dogs undergoing parathyroidectomy due to primary hyperparathyroidism

Objective

To investigate (1a) agreement of ultrasonographic, surgical, and histopathologic findings in the diagnosis of a neoplastic etiology underlying primary hyperparathyroidism (PHPT), (1b) the ability of ultrasonographically determined parathyroid gland size to distinguish between malignant (carcinoma) and non‐malignant (hyperplasia, adenoma) pathology, and (2) variables associated with postoperative hypocalcemia in dogs undergoing surgical treatment of PHPT.

Study Design

Ambidirectional cohort study.

Animals

Forty‐seven client owned dogs with PHPT (34 retrospective; 13 prospective).

Methods

Data were extracted from medical records. Method agreements were explored using Cohen's Kappa statistic. A receiver operating characteristic curve (ROC) was used to determine a cut‐off separating parathyroid pathologies. Univariable and multivariable models assessed associations between postoperative hypocalcemia and potential risk factors.

Results

Agreement of ultrasound and surgery for number and side of affected glands was 31/47 (65.9%) and 34/47 (72.3%), respectively. In 37/47 (78.7%) cases, parathyroid tissue was correctly assessed as pathologic by the surgeon. An ultrasonographic cut‐off of ≥8.0 mm (ROC AUC = 0.82) best distinguished malignant from benign pathologies. Dogs with a preoperative serum ionized calcium (iCa) concentration ≥1.75 mEq/L had 7.5 times greater odds of becoming hypocalcemic postoperatively.

Conclusion

A fair agreement existed between ultrasonographic and surgical findings in dogs with PHPT. A parathyroid mass ≥8.0 mm on ultrasonographic examination was suggestive of malignancy, while dogs with a preoperative serum iCa concentration ≥1.75 mEq/L were at increased risk for postoperative hypocalcemia in this study.

Clinical significance

This study supports the use of bilateral cervical surgical exploration to identify abnormal parathyroid glands for the treatment of PHPT.

The EANM practice guidelines for parathyroid imaging

INTRODUCTION

Nuclear medicine parathyroid imaging is important in the identification of hyperfunctioning parathyroid glands in primary hyperparathyroidism (pHPT), but it may be also valuable before surgical treatment in secondary hyperparathyroidism (sHPT). Parathyroid radionuclide imaging with scintigraphy or positron emission tomography (PET) is a highly sensitive procedure for the assessment of the presence and number of hyperfunctioning parathyroid glands, located either at typical sites or ectopically. The treatment of pHPT is mostly directed toward minimally invasive parathyroidectomy, especially in cases with a single adenoma. In experienced hands, successful surgery depends mainly on the exact preoperative localization of one or more hyperfunctioning parathyroid adenomas. Failure to preoperatively identify the hyperfunctioning parathyroid gland challenges minimally invasive parathyroidectomy and might require bilateral open neck exploration.

METHODS

Over a decade has now passed since the European Association of Nuclear Medicine (EANM) issued the first edition of the guideline on parathyroid imaging, and a number of new insights and techniques have been developed since. The aim of the present document is to provide state-of-the-art guidelines for nuclear medicine physicians performing parathyroid scintigraphy, single-photon emission computed tomography/computed tomography (SPECT/CT), positron emission tomography/computed tomography (PET/CT), and positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with pHPT, as well as in those with sHPT.

CONCLUSION

These guidelines are written and authorized by the EANM to promote optimal parathyroid imaging. They will assist nuclear medicine physicians in the detection and correct localization of hyperfunctioning parathyroid lesions.

Hereditary Endocrine Tumors and Associated Syndromes: A Narrative Review for Endocrinologists and Endocrine Surgeons

OBJECTIVE

Hereditary endocrine tumors (HET) were among the first group of tumors where predisposition syndromes were recognized. The utility of genetic awareness is having the capacity to treat at an earlier stage, screen for other manifestations and initiate family cascade testing. The aim of this narrative review is to describe the most common hereditary syndromes associated with frequently encountered endocrine tumors, with an emphasis on screening and surveillance.

METHODS

A MEDLINE search of articles for relevance to endocrine tumors and hereditary syndromes was performed.

RESULTS

The most common hereditary syndromes associated with frequently encountered endocrine tumors are described in terms of prevalence, genotype, phenotype, penetrance of malignancy, surgical management, screening and surveillance.

CONCLUSION

Medical practitioners involved in the care of patients with endocrine tumors, should have an index of suspicion for an underlying hereditary syndrome. Interdisciplinary care is integral to successful, long-term management of these patients and affected family members.

Parathyroidectomy Results in Primary Hyperparathyroidism: Analysis of the Results From a Single Center

Objectives

The curative treatment of primary hyperparathyroidism (PHPT) is surgery. Persistent and recurrent disease may develop after surgical treatment. In this study, we aimed to evaluate the surgical cure rate in patients who underwent surgery for PHPT in our clinic.

Methods

The data of patients who underwent parathyroidectomy for PHPT by two experienced surgeons between 2000 and 2015 in our clinic were retrospectively evaluated. Patients who were followed for at least 6 months after their first parathyroidectomy were included in the study. Surgical cure and persistent and recurrent disease rates were evaluated in patients.

Results

During this period, 368 interventions were performed in 357 patients (293 F and 64 M) who were operated for PHPT in our clinic, with a mean age of 54.9±13.1 years. In the first surgery, 116 patients (32.5%) had bilateral neck exploration, 251 patients (67.5%) had unilateral neck exploration (UNE) or focused parathyroid surgery (FPS). In the first operation, 343 patients (96.1%) had cure, 14 patients (13 F and 1 M) remained persistent. Secondary surgical intervention was performed in 11 patients. UNE or FPS was performed to 10 patients (90.9%); partial sternotomy was performed to one patient. Ten of the patients had cure. Three of these patients had a solitary parathyroid adenoma that was not removed in the first surgery, and seven patients had a second adenoma. Four patients remained persistent (1.1%). Recurrent disease developed in four patients during follow-up (1.1%). Total cure rate was 97.8%.

Conclusion

The only definitive treatment for PHPT is surgery. High surgical cure can be achieved by pre-operative evaluation and appropriate surgical planning. However, persistent PHPT may develop, especially due to double adenoma or ectopic location. Patients with persistent PHPT can be evaluated with repeat imaging methods and with appropriate surgical planning, a high cure rate can be obtained in secondary surgery, which can increase the total surgical cure rate. Recurrence rate is rare.

Focused parathyroidectomy without intraoperative parathyroid hormone measurement in primary hyperparathyroidism: Still a valid approach?

BACKGROUND

Concern regarding suboptimal cure rates has led to some endocrine surgery units abandoning focused parathyroidectomy for primary hyperparathyroidism in favor of open bilateral neck exploration or making intraoperative parathyroid hormone estimation mandatory in focused parathyroidectomy. This study explores whether focused parathyroidectomy for radiologically localized primary hyperparathyroidism without intraoperative parathyroid hormone is still a valid approach.

METHODS

Retrospective review of a tertiary referral endocrine surgery unit database. All parathyroidectomies for primary hyperparathyroidism over 6 years (2013-2019) were included. Lithium-induced hyperparathyroidism, reoperations, familial disease, and concurrent thyroid surgery were excluded. Characteristics and outcomes for focused parathyroidectomy and open bilateral neck exploration were compared by intention-to-treat and treatment delivered. Persistence and recurrence, conversions and complications were analyzed as endpoints.

RESULTS

A total of 2,828 parathyroidectomies were performed and 2,421 analyzed. By intention to treat there were 1,409 focused parathyroidectomies and 1,012 open bilateral neck explorations. Focused parathyroidectomy patients were younger: 63 vs 66 years (P < .01); however, gender (77%, 79% female), preoperative peak serum calcium (2.72, 2.70 mmol/L [P = .23]), and serum parathyroid hormone (11.5, 11.0 pmol/L [P = .52]) did not differ. In total, 229 (16.3%) focused parathyroidectomies were converted to open bilateral neck exploration. Multiple gland disease was confirmed in 54.5% of converted patients. Median follow-up was 41 months (3-60 months). Persistence or recurrence requiring reoperation totaled 2.2% and did not differ between focused parathyroidectomy and open bilateral neck exploration in either intention to treat or final treatment analyses. Complications occurred in 1.2% of focused parathyroidectomy and 3.2% open bilateral neck exploration (P < .01).

CONCLUSIONS

In experienced hands and with a ready-selective approach to conversion, focused parathyroidectomy based on concordant imaging and without intraoperative parathyroid hormone may deliver equivalent cure rates to open bilateral neck exploration with significantly fewer complications. Focused parathyroidectomy without intraoperative parathyroid hormone should therefore be maintained in the endocrine surgeon's armamentarium.

Advances in the diagnosis and the management of primary hyperparathyroidism

The parathyroid glands, one of the last organs to be discovered, are responsible for maintaining calcium homeostasis, and they continue to present the clinician with diagnostic and management challenges that are reviewed herein. Primary hyperparathyroidism (PHPT) comprises the vast majority of pathology of the parathyroid glands. The classic variant, presenting with elevated calcium and parathyroid hormone levels, has been studied extensively, but the current body of literature has added to our understanding of normocalcemic and normohormonal variants of PHPT, as well as syndromic forms of PHPT. All variants can lead to bone loss, kidney stones, declining renal function, and a variety of neurocognitive, gastrointestinal, and musculoskeletal complaints, although the majority of PHPT today is asymptomatic. Surgery remains the definitive treatment for PHPT, and advances in screening, evolving indications for surgery, new imaging modalities, and improvements in intra-operative methods have greatly changed the landscape. Surgery continues to produce excellent results in the hands of an experienced parathyroid surgeon. For those patients who are not candidates for surgery, therapeutic advances in medical management allow for improved control of the hypercalcemic state. Parathyroid cancer is extremely rare; the diagnosis is often made intra-operatively or on final pathology, and recurrence is common. The mainstay of treatment is normalization of serum calcium via surgery and medical adjuncts.

Challenging NICE guidelines on parathyroid surgery

BACKGROUND

National Institute of Clinical Excellence (NICE) recommend against routinely using Intra-Operative Parathyroid Hormone (IOPTH) for first-time parathyroid surgery due to its cost and minimal surgical benefit. The European Society of Endocrine Surgeons differ from this and recommends IOPTH with conflicting pre-operative or single imaging. NICE guidance acknowledged that this may change practice in larger centres. We devised a retrospective single-centre cohort study to analyse the impact of IOPTH on decision-making and cost-effectiveness.

METHODOLOGY

First-time parathyroidectomy procedures for primary hyperparathyroidism were assessed between 2017 and 2019. Ultrasound (US) and Sestamibi with parathyroid single-photon emission with computed tomography (SPECT-CT) were compared with IOPTH. The contribution of IOPTH to cure and cost effectiveness ratio was calculated.

RESULTS

114 cases were included, with IOPTH performed in all cases, SPECT-CT in 112 and US in 108 cases. A cure rate of 99.1% (113/114) was achieved. 11.4% (13/114) of the cure rate was influenced by IOPTH (P 0.01), instigating further exploration when its levels didn't decrease. This included 7.1% (4/56) in the concordant-imaging cohort. IOPTH accuracy (96.5%) was significantly superior (P = 0.03) to both US (80%) and SPECT-CT (81%). Comparing the total costs for IOPTH testing over 2 years (£39,721) with 13 potential re-operative procedures in its absence (£63,536), a positive cost-effectiveness ratio of £1832 per re-operative procedure averted was achieved.

CONCLUSION

Abandoning IOPTH in first-time parathyroid surgery is too ambitious when weighing the cost of re-operative surgery against cost savings obtained by using routine IOPTH to achieve an improved cure rate, even in concordant imaging.

Evaluation of diagnostic efficacy for localization of parathyroid adenoma in patients with primary hyperparathyroidism undergoing repeat surgery

Purpose

Repeat surgery in patients with primary hyperparathyroidism (pHPT) is associated with an increased risk of complications and failure. This stresses the need for optimized strategies to accurately localize a parathyroid adenoma before repeat surgery is performed. However, evidence on the extent of required diagnostics for a structured approach is sparse.

Methods

A retrospective single-center evaluation of 28 patients with an indication for surgery due to pHPT and previous thyroid or parathyroid surgery was performed. Diagnostic workup, surgical approach, and outcome in terms of complications and successful removement of parathyroid adenoma with biochemical cure were evaluated.

Results

Neck ultrasound, sestamibi scintigraphy, C11-methionine PET-CT, and selective parathyroid hormone venous sampling, but not MRI imaging, effectively detected the presence of a parathyroid adenoma with high positive predictive values. Biochemical cure was revealed by normalization of calcium and parathormone levels 24–48h after surgery and was achieved in 26/28 patients (92.9%) with an overall low rate of complications. Concordant localization by at least two diagnostic modalities enabled focused surgery with success rates of 100%, whereas inconclusive localization significantly increased the rate of bilateral explorations and significantly reduced the rate of biochemical cure to 80%.

Conclusion

These findings suggest that two concordant diagnostic modalities are sufficient to accurately localize parathyroid adenoma before repeat surgery for pHPT. In cases of poor localization, extended diagnostic procedures are warranted to enhance surgical success rates. We suggest an algorithm for better orientation when repeat surgery is intended in patients with pHPT.

A retrospective analysis of the diagnostic performance of 11C-choline PET/CT for detection of hyperfunctioning parathyroid glands after prior negative or discordant imaging in primary hyperparathyroidism

Background

Identifying the correct location of a parathyroid adenoma in patients with primary hyperparathyroidism (pHPT) is crucial as it can guide surgical treatment. This study aimed to determine the diagnostic performance of ¹¹C-choline PET/CT in patients with pHPT as a next in-line scan after primary negative or discordant first-line imaging.

Methods

This was a retrospective single-center cohort study. All patients with pHPT that were scanned utilizing ¹¹C-choline PET/CT, after prior negative or discordant imaging, between 2015 and 2019 and who subsequently underwent parathyroid surgery were included. The results of the ¹¹C-choline PET/CT were evaluated lesion-based, with surgical exploration and histopathological examination as the gold standard.

Results

In total, 36 patients were included of which three patients were known to have Multiple Endocrine Neoplasia (MEN) syndrome. In these 36 patients, 40 lesions were identified on ¹¹C-choline PET/CT and 37 parathyroid lesions were surgically removed. In 34/36 (94%) patients a focused parathyroidectomy was performed, in one patient a cervical exploration due to an ectopically identified adenoma, and in one patient a bilateral exploration was performed because of a double adenoma. Overall, per-lesion sensitivity of ¹¹C-choline PET/CT was 97%, the positive predictive value was 95% and the accuracy was 94% for all parathyroid lesions.

Conclusions

In patients with pHPT and prior negative or discordant first-line imaging results, pathological parathyroid glands can be localized by ¹¹C-choline PET/CT with high sensitivity and accuracy.

The utility of intraoperative nerve monitoring in secondary and tertiary Hyperparathyroid surgery

OBJECTIVES

Recurrent laryngeal nerve (RLN) injury is a well-known complication of parathyroid surgery. Despite ample data, there is still uncertainty about the role of intraoperative monitoring (IONM) in mitigating RLN damage.

STUDY DESIGN

A retrospective review.

METHODS

We included all patients presenting for total, subtotal, or completion parathyroidectomy at a tertiary referral hospital from 2013 to 2018. Information about demographics, previous neck surgery, perioperative data, pathology, and possible RLN injury was collected. Two groups were formed for analysis: IONM vs. nonmonitored (NM).

RESULTS

105 patients underwent 107 surgeries with IONM utilized in 71 cases. The groups were similar in demographics, but significantly differed (all P < 0.05) in preincision parathyroid hormone level (IONM = 2091.44 vs NM = 1334.87), surgery type (IONM = 62.9% vs NM = 27.8% subtotal), and surgery length in minutes (IONM = 155.21 vs NM = 182.22). We observed six cases (6/71 = 8.45%) of persistent RLN complaints (three or more weeks postoperatively) and four cases (4/71 = 5.63%) of temporary complaints with the use of IONM compared with only one temporary complaint (1/36 = 2.78%) in unmonitored procedures (P = 0.129).

CONCLUSIONS

These results suggest that the use of IONM does not provide a protective effect on the RLN in patients with secondary or tertiary hyperparathyroidism undergoing total, subtotal, or completion parathyroidectomy. Prospective, randomized studies with pre- and postoperative flexible laryngoscopy are needed to explore the use of IONM in this patient population further.

A Review of Parathyroid Surgery for Primary Hyperparathyroidism from the United Kingdom Registry of Endocrine and Thyroid Surgery (UKRETS)

BACKGROUND

The United Kingdom Registry of Endocrine and Thyroid Surgeons is a national database holding details on > 28,000 parathyroidectomies.

METHODS

An extract (2004-2017) of the database was analysed to investigate the reported efficacy, safety and use of intra-operative surgical adjuncts in targeted parathyroidectomy (tPTx) and bilateral neck exploration (BNE) for adult, first-time primary hyperparathyroidism (PHPT).

RESULTS

50.9% of 21,738 cases underwent tPTx. Excellent short-term (median follow-up 35 days) post-operative normocalcaemia rates were reported overall (tPTx 96.6%, BNE 94.5%, p < 0.05) and in image-positive cases (tPTx 96.7%, BNE 96%, p < 0.05). Intra-operative PTH improved overall normocalcaemia rates (tPTx 97.8% vs 96.3%, BNE 95% vs 94.4%: both p < 0.05). Intra-operative nerve monitoring reduced vocal cord (VC) dysfunction in image-positive tPTx, but not in BNE (97.8% vs 93.2%, p < 0.05). Complications were higher following BNE (7.4% vs 3.8%, p < 0.05), especially hypocalcaemia (5.3% vs 2%, p < 0.05). There was no difference in rates of subjective dysphonia following tPTx or BNE (2.4% vs 2.3%, p > 0.05), nor any difference in VC dysfunction when formally examined (4.9% vs 4.1%, p > 0.05).

CONCLUSIONS

In image-positive, first time, adult PHPT cases, tPTx is as safe and effective as BNE, with both achieving excellent short-term results with minimal complications.

Normocalcaemic primary hyperparathyroidism: An update on diagnostic and management challenges

Normocalcaemic primary hyperparathyroidism is a condition that can present with intermittent hypercalcemia or may evolve into hypercalcemic primary hyperparathyroidism. This milder biochemical entity remains incompletely understood because of a lack of long-term health outcomes regarding both medical and surgical approaches to its management. Medical therapies have shown some efficacy. A limited number of studies have found that bisphosphonates increase bone mineral density, and calcimimetics may decrease the risk of nephrolithiasis in patients with normocalcaemic primary hyperparathyroidism. Studies have also described patient outcomes after applying the same surgical criteria used for patients with hypercalcaemic primary hyperparathyroidism to those with the normocalcaemic form of the disease. These studies suggest that parathyroid surgery appears to be effective in normalizing elevated serum parathyroid hormone concentrations and decreasing adverse renal and skeletal outcomes in patients with normocalcaemic hyperparathyroidism. Given the available data and overall lack of consensus regarding the optimal management of these patients, a reasonable approach is to tailor treatment to the individual patient by considering their risk factors for new or accelerated bone loss, kidney stones, diminished quality of life, and cardiovascular disease.

4D-CT facilitates focused parathyroidectomy in patients with primary hyperparathyroidism by maintaining a high negative-predictive value for uninvolved quadrants

INTRODUCTION

Improved preoperative localization facilitates minimally invasive parathyroidectomy for removal of parathyroid lesions therefore preventing an invasive bilateral neck exploration. As 4D-CT has emerged, its high specificity has helped with preoperative parathyroid lesion localization. A high negative predictive value (NPV) would serve to further confirm parathyroid lesion localization and limit unnecessary surgical exploration. This study's objective was to determine the NPV of preoperative 4D-CT and its facilitation of minimally invasive parathyroidectomy.

METHODS

A retrospective review was compiled for patients undergoing parathyroidectomy for primary hyperparathyroidism with a preoperative 4D-CT. Included patients were sorted into various groups for comparison: those with 4D-CT localizing to a single lesion, localizing to multiple lesions, and those with nonlocalizing findings; multiple hypercellular parathyroid gland versus single gland findings; extent of surgical exploration; lesion location; and patients with concomitant thyroid nodules. Negative predictive value was calculated and used to quantify the ability for 4D-CT to rule out biochemically significant parathyroid lesions.

RESULTS

In our review of 68 patients: sensitivity was 81.3%, specificity was 95.5%, positive predictive value was 87.1%, and negative predictive value was 93.3%. 86% had a single localizing 4D-CT, 7% had a non-localizing 4D-CT, and 7% had a multiple quadrant localizing 4D-CT. NPV for single and multi-localizing 4D-CT were 96.8% and 88.9%, respectively.

CONCLUSION

Preoperative 4D-CT has a high negative predictive value (93.3%), suggesting in the majority of cases, a quadrant with no 4D-CT radiographic findings suspicious for parathyroid is unlikely to harbor biochemically significant parathyroid lesions.

Parathyroid hormone

Parathyroid hormone is an essential regulator of extracellular calcium and phosphate. PTH enhances calcium reabsorption while inhibiting phosphate reabsorption in the kidneys, increases the synthesis of 1,25-dihydroxyvitamin D, which then increases gastrointestinal absorption of calcium, and increases bone resorption to increase calcium and phosphate. Parathyroid disease can be an isolated endocrine disorder or part of a complex syndrome. Genetic mutations can account for diseases of parathyroid gland formulation, dysregulation of parathyroid hormone synthesis or secretion, and destruction of the parathyroid glands. Over the years, a number of different options are available for the treatment of different types of parathyroid disease. Therapeutic options include surgical removal of hypersecreting parathyroid tissue, administration of parathyroid hormone, vitamin D, activated vitamin D, calcium, phosphate binders, calcium-sensing receptor, and vitamin D receptor activators to name a few. The accurate assessment of parathyroid hormone also provides essential biochemical information to properly diagnose parathyroid disease. Currently available immunoassays may overestimate or underestimate bioactive parathyroid hormone because of interferences from truncated parathyroid hormone fragments, phosphorylation of parathyroid hormone, and oxidation of amino acids of parathyroid hormone.

Localization of Parathyroid Disease in Reoperative Patients with Primary Hyperparathyroidism

The localization of persistent or recurrent disease in reoperative patients with primary hyperparathyroidism presents challenges for radiologists and surgeons alike. In this article, we summarize the relevant imaging modalities, compare their accuracy in identifying reoperative disease, and outline their advantages and disadvantages. Accurate localization by preoperative imaging is a predictor of operative success, whereas negative or discordant preoperative imaging is a risk factor for operative failure. Ultrasound is a common first-line modality because it is inexpensive, accessible, and radiation-free. However, it is highly operator-dependent and less accurate in the reoperative setting than in the primary setting. Sestamibi scintigraphy is superior to ultrasound in localizing reoperative disease but requires radiation, prolonged imaging times, and reader experience for accurate interpretation. Like ultrasound, sestamibi scintigraphy is less accurate in the reoperative setting because reoperative patients can exhibit distorted anatomy, altered perfusion of remaining glands, and interference of radiotracer uptake. Meanwhile, four-dimensional computed tomography (4DCT) is superior to ultrasound and sestamibi scintigraphy in localizing reoperative disease but requires the use of radiation and intravenous contrast. Both 4DCT and magnetic resonance imaging (MRI) do not significantly differ in accuracy between unexplored and reoperative patients. However, MRI is more costly, inaccessible, and time-consuming than 4DCT and is inappropriate as a first-line modality. Hybrid imaging with positron emission tomography and computed tomography (PET/CT) may be a promising second-line modality in the reoperative setting, particularly when first-line modalities are discordant or inconclusive. Lastly, selective venous sampling should be reserved for challenging cases in which noninvasive modalities are negative or discordant. In the challenging population of reoperative patients with PHPT, a multimodality approach that utilizes the expertise of high-volume centers can accurately localize persistent or recurrent disease and enable curative parathyroidectomy.

MINIMALLY INVASIVE PARATHYROIDECTOMY FOR PRIMARY HYPERPARATHYROIDISM

Context

Primary hyperparathyroidism (PHPT), characterized by the inappropriate secretion of parathyroid hormone (PTH) with respect to the extracellular calcium concentration. Curative treatment of PHPT is surgery and bilateral neck exploration has been replaced by minimally invasive parathyroidectomy (MIP), with the advanced imaging technologies combined with radio-guided occult lesion localization (ROLL).

Objectives

The present study analyzes the MIP data from 45 patients who underwent surgery for parathyroid adenoma and debates if MIP is a feasible technique for the treatment of PHPT.

Design

The study presents the MIP excision data of 45 hyperparathyroidism patients with a 58-month follow up period.

Results

Forty-five operations were performed for 48 parathyroid adenomas. The mean duration of operation was 22.7 (12-55) minutes. Mean follow-up was 14.2 (6-26) months. All patients had normal postoperative calcium levels and PTH levels were normal in the follow-up period, except for one persistent hyperparathyroidism.

Conclusions

ROLL-guided MIP is a feasible technique for parathyroid surgery and reduces surgeon based failure. It also provides the widespread application of parathyroid surgery by decreasing the need for specific experience.