New trends in parathyroid surgery

Temporal research trends in parathyroid surgery

BACKGROUND

Progress has been observed in the pathophysiology of calcium homeostasis, localization studies, and intraoperative adjuncts in parathyroid surgery. The aim of this study is to gain a comprehensive perspective on the research landscape of parathyroid surgery over time.

METHODS

A search of the Web of Science Core Collection was conducted to identify publications on parathyroid surgery from 1985 to 2024. Keywords were manually curated, and their frequencies were calculated based on the publication year.

RESULTS

Publications on secondary hyperparathyroidism have decreased in recent years, but those on calcimimetics, tertiary hyperparathyroidism, and parathyroid cancer have increased. Publications related to sestamibi scans have decreased, while research on four-dimensional computed tomography and positron emission tomography has increased. Research on fluorescence and ablation treatment has recently been on the rise. The citation count per publication was positively correlated with the number of contributing institutions.

CONCLUSION

We provide an overview of contemporary research themes and emerging topics related to parathyroid surgery. The endocrine surgery community could benefit from more inter-institutional partnerships to foster scientific progress.

Impact of successful secondary hyperparathyroidism treatment on cardiovascular morbidity in patients with chronic kidney disease KDIGO stages G3b-5

INTRODUCTION

Chronic kidney disease is common, with a projected increase to 5.4 million people in need of kidney replacement therapy by 2030. As many as 61.7% of patients on hemodialysis have secondary hyperparathyroidism (SHPT). This has been associated with high cardiovascular morbidity. The present study investigates the effect of SHPT treatment success on cardiovascular morbidity in patients with CKD KDIGO stages G3b, 4, and 5.

METHODS

A retrospective single center analysis of 211 chronic kidney disease stages G3b-5 patients undergoing computed tomography for coronary artery calcium (CAC) scoring at the University Hospital of Zurich between 2015 and 2019 was performed. The presence of and control of SHPT was assessed at the timepoint of CAC scoring and 6-12 months prior. Information on left ventricular ejection fraction (LVEF), left ventricular hypertrophy (LVH), and left ventricular myocardial mass index (LVMMI) were calculated from echocardiography values obtained at the timepoint of CAC scoring. Occurrence of major acute cardiovascular events, including acute coronary syndrome (ACS), within 1 year of CAC scoring was drawn from the charts. Independent predictive factors for ACS and LVH were assessed by multivariable analysis.

RESULTS

Thirty-four percent (n=72) of the patients had uncontrolled SHPT, whereas 66% (n=139) had either no (n=18%, n=39) or a controlled SHPT (n=48%, n=100). The CKD stage G3b-5 patients with uncontrolled SHPT had a significantly lower LVEF (p=0.028) and significantly more pronounced LVH (p=0.003) and a higher LVMMI (p=0.002) than the group with either no SHPT or well-controlled SHPT. Uncontrolled SHPT in the observed CKD cohort had a significantly higher risk for developing ACS (p=0.011, HR 2.76, 95%CI 1.26-6.05) compared to no or controlled SHPT patients (41.7% vs 31.7%). While patients with uncontrolled SHPT showed a median CAC score of 290 (IQR 18-866), those with no or controlled SHPT had a lower median CAC score of 194 (IQR 14-869), although not significant (p=0.490). Patients with CAC scores >400 displayed a significantly higher incidence of ACS (56.8% vs 33.1%, p=0.010).

CONCLUSIONS

SHPT is common (82%) in advanced CKD (≥G3b) patients and insufficiently controlled in one-third of patients. Insufficient control of SHPT is associated with higher cardiovascular morbidity, lower LVEF, increased LVH, and a higher incidence of ACS. Thus, increased focus on SHPT control in CKD patients may have a beneficial impact on cardiovascular outcomes.

Sonographic Features of Atypical and Initially Missed Parathyroid Adenomas: Lessons Learned From a Single-Center Cohort

CONTEXT

Awareness of typical and atypical ultrasonographic (US) features of parathyroid adenomas (PAs) is crucial since US is the most widely used first-line imaging modality.

OBJECTIVE

The purpose of this study was to describe the atypical features of PAs on US and other possible factors leading to a false negative examination in a large single-center cohort.

MATERIALS AND METHODS

The US records of 457 PAs in 445 patients with biochemically proven primary hyperparathyroidism (PHPT) were evaluated in a prospectively maintained database. Atypical size, composition, shape, echogenicity, location, and vascular pattern on US were noted. For patients who previously had at least one negative US examination in referring centers, the main possible reason was defined accordingly.

RESULTS

The study group included 359 female and 86 male patients with PHPT. Typical sonographic features were observed in 231 PAs (51%), whereas 226 (49%) had at least one atypical US feature. The most common atypical features were atypical size (29%), followed by atypical echogenicity (19%), shape (8%), location (7%), and composition (7%), respectively. There were 122 initially missed PAs in all groups. The most frequent main atypical US features leading to false negative examinations were atypical size (22.1%) and atypical location (18.8%). Inexperience was third most common reason (16.3%) for false negative US examinations.

CONCLUSIONS

Almost half of PAs have at least one atypical feature on US. Awareness of the high prevalence of atypical US features could increase the accuracy of US examination and potentially decrease demand for more expensive second-line imaging modalities.

Comparison of Medical Management versus Parathyroidectomy in Patients with Mild Primary Hyperparathyroidism: A Meta-Analysis

BACKGROUND

Parathyroidectomy is the definitive cure for patients with primary hyperparathyroidism (pHPT) and has an annual prevalence of 0.2-1% in the United States. Some patients with mild disease are medically managed effectively using calcium-lowering medications and drugs against complications such as osteoporosis; however, many maintain a persistently high calcium level that negatively impacts their skeletal, renal, and psychogenic systems over the long term. This meta-analysis aims to compare the outcomes of medical management versus parathyroidectomy in patients with mild pHPT.

STUDY DESIGN

This meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using PubMed, Embase, and Web of Science by two teams of investigators. Analysis was run using R packages.

RESULTS

A total of 12 publications including seven randomized control, two prospective, and three retrospective trials with a total of 1346 patients were included for analysis. The average follow-up for all patients was 41 ± 23.8 months. Demographics, pre-treatment calcium, PTH, and bone mineral density (BMD) were similar between the medical (N = 632) and surgical (N = 714) cohorts. Post-treatment calcium and PTH levels were significantly higher in the medical cohort (10.46 vs. 9.39, p < 0.01), (106.14 vs. 43.25, p = 0.001), respectively. Interestingly, the post-treatment PTH in the medical cohort increased when compared to pre-treatment (83.84 to 106.14). Patients in the medical cohort had lower BMD in lumbar (0.48 g/cm²; OR = 0.42, 95% CI = 0.21, 0.83), femoral (0.48; OR = 0.42, 95% CI = 0.29, 0.61), and hip (0.61; OR = 0.33, 95% CI = 0.13, 0.85). Incidences of fracture, nephrolithiasis, cardiovascular death, or overall mortality were not significantly different between the cohorts.

CONCLUSIONS

The present study is the most comprehensive meta-analysis on mild pHPT to date. Our findings reflect that parathyroidectomy is the superior option in the treatment of mild pHPT patients as opposed to medical management.

Single-Center Experience of Parathyroidectomy Using Intraoperative Parathyroid Hormone Monitoring

Background and Objectives: Hyperparathyroidism (HPT) is a rare endocrine disease associated with the elevated metabolism of calcium, vitamin D, and phosphate by the hyperfunctioning of the parathyroid glands. Here, we report our experience of parathyroidectomy using intraoperative parathyroid hormone (IOPTH) monitoring in a single tertiary hospital. Materials and Methods: From October 2018 to January 2022, a total of 47 patients underwent parathyroidectomy for HPT. We classified the patients into two groups—primary HPT (PHPT, n = 37) and renal HPT (RHPT, n = 10)—and then reviewed the patients’ data, including their general characteristics, laboratory results, and perioperative complications. Results: Thirty-five of the thirty-seven patients in the PHPT group underwent focused parathyroidectomy, while all ten patients in the RHPT group underwent subtotal parathyroidectomy. IOPTH monitoring based on the Milan criteria was used in all cases. Preoperative and 2-week, 6-month, and 12-month postoperative parathyroid hormone (PTH) levels were within the normal range in the PHPT group, whereas they were higher than normal in the RHPT group. Transient hypocalcemia occurred only in the RHPT group, with calcium levels returning to normal levels 12 months after surgery. Conclusions: Parathyroidectomy with IOPTH monitoring in our hospital showed favorable clinical outcomes. However, owing to the small number of patients due to the low frequency of parathyroid disease, long-term, prospective studies are needed in the future.

Tumor size rather than the thyroid invasion affects the prognosis of parathyroid carcinoma without lymph node or distant metastasis

PURPOSE

This study aimed to explore the prognostic value of thyroid invasion of parathyroid carcinoma without lymph node or distant metastasis.

METHODS

Two hundred and nine cases of parathyroid carcinoma from the SEER (1989-2014) were eligible for this study. A Chi-squared test, t test, X-tile, Kaplan-Meier curves, and multivariate Cox proportional hazard regression were used for analysis.

RESULTS

Thyroid invasion, sex, race, age, radiation, and surgery were not significantly associated with cancer-specific survival by multivariate analysis. However, tumor size ≥ 4 cm was significantly associated with worse cancer-specific survival (P < 0.001).

CONCLUSION

Thyroid invasion, which was the criterion for T₁ and T₂ staging criteria of parathyroid carcinoma according to the AJCC, did not affect the prognosis of patients with parathyroid carcinoma without local lymph node or distant metastasis. Our study indicates that a tumor size ≥ 4 cm may be an appropriate indicator of T₁ and T₂ cancer staging.

Recurrence after successful parathyroidectomy-Who should we worry about?

BACKGROUND

Preventing cervical reoperations is important-especially after parathyroidectomy. We sought to examine early predictors of recurrence of primary hyperparathyroidism after surgical cure.

METHODS

Adult patients with sporadic primary hyperparathyroidism treated with parathyroidectomy between September 1, 1997, and September 1, 2019, with confirmed eucalcemia at 6 months postoperatively were identified. Recurrence was defined as hypercalcemia (>10.2 mg/dL) with an elevated or nonsuppressed parathyroid hormone level on subsequent follow-up.

RESULTS

Parathyroidectomy was performed in 522 patients (median age, 62.1 years, 77% female) with the majority undergoing planned minimally invasive parathyroidectomy (85.4%, n = 446). After a median follow-up of 30.9 months, 13 patients (2.5%) recurred (median time to recurrence 50.2 months, interquartile range 27.9-66.5), all of whom underwent planned minimally invasive parathyroidectomy (n = 13/446, 2.9%). Recurrence was more common in those with higher (but still normal) 6-month calcium (10.1 vs 9.3 mg/dL, P < .001) or parathyroid hormone values (64 vs 46 pg/mL, P < .01). Multivariate analysis revealed that age >66.5 years, calcium ≥9.8mg/dL and parathyroid hormone ≥80 pg/mL at 6 months were associated with increased risk of recurrence. In addition, the presence of at least 1 preoperative imaging study that conflicted with intraoperative findings among minimally invasive parathyroidectomy patients (n = 446) was associated with increased risk of recurrence (hazard ratio 4.93, 95% confidence interval 1.25-16.53, P = .016).

CONCLUSION

Recurrence of sporadic primary hyperparathyroidism after initial surgical cure in the era of minimally invasive parathyroidectomy is 2.5%. Identification of those at risk for recurrence using 6-month serum calcium ≥9.8 mg/dL, parathyroid hormone ≥80 pg/mL, and/or potentially conflicting localization studies may inform surveillance strategies.

Unexpected remission of hyperparathyroidism caused by hemorrhage due to the use of fine-needle aspiration biopsy: two cases report

Hyperparathyroidism is not a rare disease; if a parathyroid adenoma is confirmed, the treatment of choice is the surgical resection. Diagnostic use of fine-needle aspiration biopsy (FNAB) for histological confirmation in patients with hyperparathyroidism is controversial. And spontaneous remission of hyperparathyroidism caused by bleeding or infarction of the adenoma rarely occurs. Here we have reported two cases of hyperparathyroidism in which spontaneous remission occurred due to the use of FNAB for diagnosis. The remission was confirmed after surgical removal and pathological review of the adenoma. The first patient diagnosed with primary hyperparathyroidism (PHPT) had neck pain and severe swelling 4 days after FNAB, and spontaneous remission due to intracapsular hemorrhage was confirmed after surgery. In the second patient receiving hemodialysis treatment for end-stage renal disease, hyperparathyroidism spontaneously resolved after FNAB and the parathyroid hormone (PTH) levels normalized after surgery. The first patient maintained a normal level of PTH for 6 years, and the second patient received kidney transplantation 6 years after surgery, and the normal level of PTH was confirmed for 13 years. Caution is needed while performing FNAB for diagnosis of hyperparathyroidism and during decision making regarding whether to observe the patient or perform surgery after spontaneous remission due to bleeding or infarction.

Image-guided Endoscopic Parathyroidectomy Using the Axillo-breast Approach in the Treatment of Primary Hyperparathyroidism

BACKGROUND

Focused parathyroidectomy is currently performed using minimal access techniques. Here, we aim to evaluate the outcomes of the axillo-breast totally endoscopic approach (ABTEA) in patients with primary hyperparathyroidism caused by a single parathyroid adenoma.

PATIENTS AND METHODS

Ten patients with primary hyperparathyroidism were retrospectively evaluated. In all patients, the presence of a single parathyroid adenoma was confirmed using cervical ultrasonography by an expert radiologist with or without the use of parathyroid scintigraphy. All patients underwent focused parathyroidectomy using ABTEA. Clinicopathologic characteristics, surgical outcomes, biochemical cure rates, and cosmetic outcomes were evaluated.

RESULTS

The parathyroid adenoma was successfully excised in all patients without significant complications and without conversion to open approach. All patients were cured, with ≥6 months of follow-up. Temporary hoarseness of the voice was observed in 1 case. The mean surgical time was 91±17.61 minutes. The mean blood loss was 20 mL. The postoperative pain scores were satisfactory and 90% of patients were extremely satisfied with the procedure.

CONCLUSION

With accurate preoperative sonographic localization of a single parathyroid adenoma, focused parathyroidectomy using ABTEA is a safe and feasible technique even for posteriorly located parathyroid adenomas.

Parathyroidectomy Resolves Tooth Discoloration: A New Presenting Sign of Hyperparathyroidism?

Introduction

We report the resolution of tooth discoloration following parathyroidectomy in an otherwise asymptomatic woman with primary hyperparathyroidism-associated hypercalcemia. Case Report. A 59-year-old Caucasian woman, diagnosed with primary hyperparathyroidism in 2011, nonsmoker with excellent overall oral health. She complained of tooth discoloration starting in 2013. Pigmentation was particularly evident in the necks of the lower central and lateral incisors (Vita Classical score C2). No bleaching was undertaken. Parathyroidectomy was performed five years after primary hyperparathyroidism diagnosis. Six months later, a reduction in pigmentation was strikingly evident, with incisors scoring A1 and A2. The improvement persisted over time. Tooth value also increased compared to baseline.

Conclusions

This is, to our knowledge, the first report that parathyroidectomy might resolve dental discoloration. This outcome deserves investigation in a meaningful sample size and may eventually prompt the inclusion of dental issues among the consequences of primary hyperparathyroidism.

Preoperative localization modalities in primary hyperparathyroidism: Correlation with postoperative cure

BACKGROUND

Accurate preoperative localization is critical to the success of minimally invasive parathyroidectomy. This investigation aimed to assess the correlation among preoperative imaging results, intraoperative findings, and postoperative cure rates in patients undergoing operation for primary hyperparathyroidism.

METHODS

A retrospective review of all patients who underwent operation for primary hyperparathyroidism between June 2010 and March 2016 was performed.

RESULTS

During the study period, 398 patients underwent parathyroidectomy. The overall cure rate was 97.5%. The ultrasonography performed by the surgeon was superior to the ultrasonography performed by the radiologist and to the sestamibi scan in lateralizing the adenoma correctly (80% vs 62% vs 70%, P < .001, respectively), and had the greatest sensitivity (93%) and accuracy (80%) among all tests (P < .001). Age ≥65 was found to be associated with lesser cure rates (94% vs 99.2%, P = .003). The number of positive preoperative studies correlated with cure rate, ranging from 80% for patients with 0 positive studies, to 100% in those with 4 positive studies (P = .0004). In patients with a negative sestamibi and an ultrasonography performed by the radiologist, there was no significant difference in the cure rates among those with no preoperative computed tomography, a positive preoperative computed tomography, or a negative preoperative computed tomography.

CONCLUSION

An ultrasonography performed by an experienced surgeon is an extremely valuable preoperative localization modality. The cure rate obtained is proportional to the number of positive imaging studies. In patients with negative ultrasonography performed by a nonexperienced radiologist and a negative sestamibi scan, the performance of computed tomography does not seem to increase cure rate. Patients with no positive preoperative scans represent a challenging subgroup, with cure rates of approximately 80%.

Management of Primary Hyperparathyroidism: Can We Do Better?

The failure to follow national guidelines in management of various diseases has been previously established. We sought to quantify primary care providers’ familiarity with primary hyperparathyroidism as it affects adherence to the 2009 National Institute of Health (NIH) consensus recommendations in treatment of primary hyperparathyroidism. A large primary care group was surveyed to determine their familiarity with the 2009 NIH consensus recommendations for management of primary hyperparathyroidism (PHPT). Retrospective review of the group's records (2009–2011) was performed to verify compliance. Survey responders included 109 clinicians, 31 per cent were familiar with all criteria for surgical intervention in asymptomatic patients and 34 per cent correctly identified appropriate surveillance testing for patients undergoing observation. Chart review identified 124 patients with PHPT. Of the patients who met NIH criteria, 34 per cent had a parathyroidectomy. Younger age, higher intact parathyroid hormone, hypercalciuria, and history of nephrolithiasis were associated with surgery in multivariable analysis. Of the observed patients, 16 per cent had appropriate surveillance studies. In conclusion, this study confirms suboptimal adherence with consensus recommendations in management of PHPT. A minority of clinicians demonstrated solid familiarity with management strategies, paralleling their treatment approach. Educational efforts may improve adherence with upcoming national recommendations.

Is focused parathyroidectomy appropriate for patients with primary hyperparathyroidism?

Purpose

The aim of this study was to determine whether focused or complete parathyroidectomy was more appropriate and to compare follow-up data in primary hyperparathyroidism (PHPT).

Methods

We retrospectively analyzed 225 operations for PHPT at Yonsei University Health System between 2000 and 2012. After excluding 93 patients, the remaining 132 were divided into 2 groups: those who underwent focused parathyroidectomy (FP) and those who underwent conventional parathyroidectomy (CP). We compared clinicopathological features; preoperative calcium, parathyroid hormone (PTH), phosphorus, vitamin D, 24-hour urine calcium, and alkaline phosphatase levels; postoperative calcium and PTH levels; pathologic diagnosis; multiplicity; and results of a localization study between the 2 groups.

Results

There was no significant difference in the rates of development of postoperative persistent hyperparathyroidism (1/122 FP patients and 1/10 CP patients) between the 2 groups due to a technical reason (FP 0.8% vs. CP 10.0%, P = 0.146). Multiglandular disease (MGD) was uncommon in all cases (6 of 132, 4.5%). All MGD cases were diagnosed using a preoperative localization study. Sestamibi scan and ultrasonography sensitivity were 94.2% and 90.2%, respectively.

Conclusion

We suggest that FP is appropriate in PHPT, except in cases of MGD if detected before the operation using preoperative imaging. Knowledge of hereditary PHPT and improved preoperative localization studies, such as high-resolution ultrasonography, contributed to the decision to perform FP rather than CP in all cases of unilateral results of the localizing study.

No Need to Abandon Focused Unilateral Exploration for Primary Hyperparathyroidism with Intraoperative Monitoring of Intact Parathyroid Hormone

BACKGROUND

We investigated the rate of persistent and recurrent hyperparathyroidism after focused unilateral exploration (UE) with intraoperative monitoring of intact parathyroid hormone (IOPTH).

STUDY DESIGN

A prospective cohort of 915 patients with primary hyperparathyroidism (PHP) underwent parathyroid surgery by a single surgeon from January 2003 to September 2013. A total of 556 patients with at least a single positive preoperative localization by ultrasound (US) and/or sestamibi scan (STS) underwent UE with IOPTH. The criterion for completion of surgery was an IOPTH fall of 50% from the highest intraoperative level and into the normal range 5 to 10 minutes after resection of the localized gland.

RESULTS

Fifteen patients had either persistent or recurrent PHP, yielding a 2.7% (95% CI 1.6% to 4.4%) overall recurrence rate based on the refined Wilson method with continuity correction. Four patients had persistent PHP. Three of these patients were cured with reoperation, and the fourth patient was followed nonoperatively. Eleven patients had recurrent PHP, with 5 corrected by surgery and 6 patients followed nonoperatively. The mean postoperative serum calcium (Ca) level was 9.4 mg/dL over a mean follow-up interval of 44.0 months. Preoperative localization rates by each localization study were: US 74.3% (n = 413), STS 86.9% (n = 483), and US and STS 71.4% (n = 397). There was no difference in the preoperative study that localized the hyperfunctional parathyroid gland in recurrent vs nonrecurrent patients by the Fisher's exact test (US, p =1.00; STS, p =0.65; US and STS, p =1.00).

CONCLUSIONS

The low rate of recurrent PHP after focused unilateral exploration with IOPTH suggests that this procedure should not be abandoned.

Kidney Disease Improving Global Outcomes guidelines and parathyroidectomy for renal hyperparathyroidism

BACKGROUND

Patients with end-stage renal disease develop hypocalcemia, resulting in secondary hyperparathyroidism (SHPT). No clear criterions exist to aid in surgical decision making for SHPT. The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines provide target ranges for serum calcium, phosphate, and parathyroid hormone (PTH) levels in patients with end-stage renal disease. Parathyroidectomy can help achieve these targets. The study purpose was to examine how parathyroidectomy for SHPT impacts KDIGO targets during immediate and long-term follow-up and to evaluate KDIGO categorization with receipt of additional surgical intervention.

METHODS

A retrospective review of a prospective parathyroidectomy database was performed. Included patients had SHPT, were on dialysis, and underwent parathyroidectomy. Calcium, phosphate, and PTH values were classified as below, within, or above KDIGO targets.

RESULTS

Between 2000 and 2013, 36 patients with SHPT met criteria. Subtotal parathyroidectomy was performed in 89%, total parathyroidectomy in 11%. Follow-up time was 54 ± 7 mo. Eight patients (22%) required additional surgery. Twenty-eight patients (76%) were alive at the last follow-up. At the last-follow up, patients had phosphate (46%), and PTH (17%) above KDIGO ranges. Factors associated with reoperation were assessed. Patient PTH within or above target immediately postoperative had a higher rate of reoperation (P < 0.01). At the last follow-up, higher phosphate (P = 0.054) and PTH (P < 0.001) were associated with higher reoperation rates, but calcium (P = 0.33) was not.

CONCLUSIONS

PTH and phosphate levels above KDIGO indices were associated with additional surgical intervention. Many patients had laboratory indices above range at the last follow up, suggesting more patients had persistent or recurrent disease than those who underwent reoperation. Patients may benefit from more aggressive medical and/or surgical management.

Is central lymph node dissection necessary for parathyroid carcinoma?

BACKGROUND

Parathyroid carcinoma is a rare cancer. Unlike other more common malignancies, the importance of lymph node (LN) status remains controversial. The purpose of this study was to determine the relative importance of LN metastases in disease-specific survival (DSS).

METHODS

A retrospective review of the Surveillance, Epidemiology, and End Result database was performed on parathyroid carcinoma cases diagnosed between 1988 and 2010.

RESULTS

We identified 405 parathyroid carcinoma patients. Among 114 patients with LNs examined at operation, only 12 (10.5%) had positive LNs. Sensitivity analysis found that a tumor size threshold of 3 cm best divided the cohort by DSS. Only tumors ≥ 3 cm and distant metastasis but not LN metastases were independent prognostic factors on multivariate analysis. When examining factors associated with LN status, only tumors ≥ 3 cm predicted LN metastasis. LN metastases were 7.5 times more likely in patients with tumors ≥ 3 cm than those with tumors <3 cm.

CONCLUSION

Tumors ≥ 3 cm were associated with LN metastases in parathyroid carcinoma, but positive LN status was not associated with DSS. Tumor size can potentially risk stratify patients by their risk of LN metastases.

Primary hyperparathyroidism: an analysis of failure of parathyroidectomy

BACKGROUND

Preoperative imaging in patients undergoing surgery for primary hyperparathyroidism (PHPT) is used primarily to facilitate targeted parathyroidectomy. Failure of preoperative localisation mandates a bilateral exploration. It is thought that the results of imaging may also predict the success of surgery. The aims of this study were to assess whether the findings on preoperative localisation influenced outcomes following parathyroidectomy for PHPT and to explore factors underlying failure to cure at surgery.

METHODS

We analysed outcomes of all patients who underwent first-time surgery for PHPT in two centres over a 5-year period to determine an association with demographic characteristics and findings on preoperative imaging. Records of patients not cured by initial surgery were reviewed to explore factors underlying failure to cure.

RESULTS

The failure rate (persistent disease) in the entire cohort was 5 % (25/541) (bilateral neck explorations, 5 %; unilateral exploration, 7 %; targeted approach, 4 %), while two patients developed recurrent disease. In patients who had undergone dual imaging with an ultrasound scan and (99m)Tc-sestamibi scintigraphy, failure rates with "lateralised and concordant" imaging, "nonconcordant" imaging, and "dual-negative" imaging were 2, 9, and 11 %, respectively (p = 0.01). Of the 25 patients with persistent disease, multigland disease (MGD) was present in 52 % (13/25) and ectopic adenoma in 24 % (6/12).

CONCLUSIONS

Patients with PHPT who do not have lateralised and concordant dual imaging are at higher risk of persistent disease. A significant proportion of failures are due to the inability to recognise the presence and/or extent of MGD.

Mild primary hyperparathyroidism: a literature review

The biochemical profile of classic primary hyperparathyroidism (pHPT) consists of both elevated calcium and parathyroid hormone levels. The standard of care is parathyroidectomy unless prohibited by medical comorbidities. Because more patients are undergoing routine bone density evaluation and neck imaging studies for other purposes, there is a subset of people identified with a biochemically mild form of the pHPT that expresses itself as either elevated calcium or parathyroid hormone levels. These patients often do not fall into the criteria for operation based on the National Institutes of Health consensus guidelines, and they can present a challenge of diagnosis and management. The purpose of this paper is to review the available literature on mild pHPT in an effort to better characterize this patient population and to determine whether patients benefit from parathyroidectomy. Evidence suggests that there are patients with mild pHPT who have overt symptoms that are found to improve after parathyroidectomy. There is also a group of patients with biochemically mild pHPT who are found to progress to classic pHPT over time; however, it is not predictable which group of patients this will be. Early intervention for this group with mild pHPT may prevent progression of bone, psychiatric, and renal complications, and parathyroidectomy has proven safe in appropriately selected patients at high volume centers.

Predictors of recurrence in primary hyperparathyroidism: an analysis of 1386 cases

OBJECTIVE

The purpose of this study was to determine whether the operative approach independently influenced recurrence and to identify perioperative predictors of recurrence.

BACKGROUND

Intraoperative parathyroid hormone (IoPTH) monitoring has enabled surgeons to perform minimally invasive parathyroidectomy (MIP). Yet, the long-term durability of this approach has recently been questioned.

STUDY DESIGN

A retrospective review was performed, and cases of initial neck surgery for nonfamilial primary hyperparathyroidism were selected for analysis. Cases were classified as either open parathyroidectomy (OP) when both sides of the neck were explored or MIP when only one side was explored. Kaplan-Meier estimates were plotted for disease-free survival, and a Cox proportional hazards model was developed to evaluate factors associated with recurrence for both the entire cohort and the MIP subset. Further comparisons were made between those who recurred and those who did not recur.

RESULTS

In the past 10-year period, 1368 parathyroid operations for primary hyperparathyroidism were performed at our institution. A total of 1006 were MIP whereas 380 were OP. There were no differences in recurrence between the MIP and OP groups (2.5% vs 2.1%; P = 0.68), and the operative approach (MIP vs OP) did not independently predict recurrent disease in our multivariate analysis. The percentage decrease in IoPTH was protective against recurrence for both the entire cohort (hazard ratio = 0.96; 95% confidence interval = 0.93-0.99; P = 0.03) and the MIP subset. A higher postoperative PTH also independently predicted disease recurrence.

CONCLUSIONS

Operative approach does not independently predict recurrent hyperparathyroidism. The percentage decrease in IoPTH is one of many adjuncts the surgeon can use to determine which patients are best served by bilateral exploration whereas the postoperative PTH can guide follow-up after parathyroidectomy.

Minimal benefit to subsequent intraoperative parathyroid hormone testing after all four glands have been identified

BACKGROUND

Modern tools, such as intraoperative parathyroid hormone (IoPTH) assay, reduce operative time and extent of parathyroidectomy. However, the utility of a subsequent final set of IoPTH after all four glands are visualized remains questionable. This study was designed to determine the added value of IoPTH assay following parathyroidectomy with four-gland visualization in patients with primary hyperparathyroidism (PHPT).

METHODS

A retrospective review of patients who underwent parathyroidectomy for PHPT between July 2001 and February 2012 by two experienced endocrine surgeons was performed. Included were patients with operative reports indicating that all four parathyroid glands were identified. Following four-gland visualization a subsequent final set of IoPTH was measured to confirm cure. Cure was defined as at least 50 % fall by 5, 10, or 15 min postexcision compared with preincision levels.

RESULTS

Of 1,838 patients that underwent parathyroidectomy, four glands were visualized in 238 cases (13 %). Of those patients meeting inclusion criteria with four glands visualized, the final set of IoPTH fell to cure criteria in 235 patients (98 %). An inadequate drop was documented in three (2 %) patients all of which were found to have multigland disease. Only in one patient (0.4 %) was a fifth parathyroid gland identified and resected. In all three cases, the subsequent final IoPTH did not affect the ultimate outcome or cure rate.

CONCLUSIONS

When experienced surgeons visualize all four parathyroid glands, drawing a subsequent final set of IoPTH rarely changes the operative course and therefore serves a limited role.

Multigland disease and slower decline in intraoperative PTH characterize mild primary hyperparathyroidism

BACKGROUND

Many patients with primary hyperparathyroidism (PHPT) present with less severe biochemical parameters. The purpose of this study was to compare the presentation, operative findings, and outcomes of these patients with "mild" PHPT to patients with "overt" disease.

METHODS

A retrospective review of a prospectively collected parathyroid database was performed to identify cases of PHPT undergoing an initial neck operation. Patients were classified as mild when either the preoperative calcium or PTH was within the normal limits. Comparisons were made with the Student's t test, Chi-squared test, or Wilcoxon rank-sum test where appropriate. Kaplan-Meier estimates were plotted for disease-free survival and compared by the log-rank test.

RESULTS

Of the 1,429 patients who met inclusion criteria, 1,049 were classified as overt and 388 (27.1 %) were mild. Within the mild group, 122 (31.4 %) presented with normocalcemic PHPT and 266 (68.6 %) had a normal PTH. The two groups had similar demographics and renal function. Interestingly, the mild group had more than double the rate of kidney stones (3.1 vs. 1.3 %, p = 0.02). The mild group was less likely to localize on sestamibi scan (62.4 vs. 78.7 %, p < 0.01). Intraoperatively, more mild patients exhibited multigland disease (34.3 vs. 14.1 %, p < 0.01). When examining intraoperative PTH (IoPTH) kinetics where single adenomas were excised, the IoPTH fell at a rate of 6.9 pg/min in mild patients compared with 11.5 pg/min in the overt group (p < 0.01). Accordingly, 62.2 % of patients in the overt group and 53.3 % in the mild group were cured at 5 min postexcision (p < 0.01). There was no difference in the rates of persistence or recurrence between the groups, and disease-free survival estimates were identical (p = 0.27).

CONCLUSIONS

Patients with mild PHPT were more likely to have multigland disease and a slower decline in IoPTH, but these patients can be successfully treated with surgery.

Radioguided parathyroidectomy effective in pediatric patients

BACKGROUND

Radioguided parathyroidectomy (RGP) has been shown to be effective in adult patients with hyperparathyroidism (HPT), but the utility of RGP in pediatric patients has not been systematically examined. It is not known if adult criteria for radioactive counts can accurately detect hyperfunctioning parathyroid glands in pediatric patients. The purpose of our study was to determine the utility of RGP in children with primary HPT.

MATERIALS AND METHODS

A retrospective review of our prospectively maintained single-institution database for patients who underwent a RGP for primary HPT identified 1694 adult and 19 pediatric patients aged 19 y or younger. From the adult population, we selected a control group matched three to one for gland weight and gender and compared pre- and postoperative laboratory values, surgical findings, pathology, and radioguidance values between the control and the pediatric groups.

RESULTS

Excised glands from pediatric patients were smaller than those in the total adult population (437 ± 60 mg versus 718 ± 31 mg, P = 0.0004). When controlled for gland weight, ex vivo counts as a percentage of background were lower in the pediatric group (51% ± 5% versus 91% ± 11%, P = 0.04). However, ex vivo radionuclide counts >20% of the background were found in 100% of pediatric patients and 95% of the adult-matched control group.

CONCLUSIONS

All pediatric patients met the adult detection criteria for parathyroid tissue removal when a RGP was performed, and 100% cure was achieved. We conclude that RGP is a useful treatment option for pediatric patients with primary HPT.

Significance of rebounding parathyroid hormone levels during parathyroidectomy

BACKGROUND

Using minimally invasive parathyroidectomy (MIP), most surgeons require a 50% decline in intraoperative parathyroid hormone (IoPTH) to determine cure, but the significance of IoPTH kinetics occurring after this drop remains unknown. The aim of this study was to determine the impact of IoPTH levels that first meet criteria for cure, but then increase again, or rebound, between 10 and 15 min postexcision.

METHODS

We conducted a retrospective review of patients undergoing initial parathyroidectomy for primary hyperparathyroidism at our institution from 2001 to 2011. Rebound IoPTH was defined as an increase in parathyroid hormone ≥5 pg/mL after achieving the 50% drop required for cure. Comparisons were evaluated with the Student t-test, chi-square test, or Fisher exact test where appropriate.

RESULTS

Of the 1386 patients who met selection criteria, 86 (6.2%) patients exhibited rebound IoPTH. The mean magnitude of rebound was 13.8 ± 3.6 pg/mL. Compared with those not displaying rebound, more patients with rebound IoPTH were treated with open parathyroidectomy rather than MIP (10.8% versus 4.5%, P < 0.01). The recurrence rate among those with rebound IoPTH was more than double that of the patients without rebound IoPTH (5.8% versus 2.2%, P = 0.03). Magnitude of rebound, however, did not correlate with recurrence. The rate of persistent disease was not different between those with and without rebound IoPTH. Rebound was a much better indicator of recurrence than patients whose final IoPTH levels were not within the normal range.

CONCLUSIONS

Rebound IoPTH is more common in patients who develop recurrent hyperparathyroidism. Therefore, surgeons should closely monitor patients with rebound IoPTH for disease recurrence.

Surgical treatment of primary hyperparathyroidism: description of techniques and advances in the field

Primary hyperparathyroidism is a disease commonly seen in patients above 60 years of age. It is the most common cause of asymptomatic or symptomatic hypercalcemia, usually found incidentally on routine check-ups. Surgical treatment is the only definitive treatment of choice in the symptomatic patient; however, it can also be employed in asymptomatic patients. First described in 1925, bilateral neck exploration is the gold standard of treatment for primary hyperparathyroidism. The recent interest in minimally invasive surgeries has led to better and improved techniques of neck exploration with improved cosmetic results and lesser chances of transient or permanent hypoparathyroidism due to inadvertent removal of normally functioning parathyroid tissue. These include unilateral neck explorations, minimally invasive parathyroidectomies and minimally invasive radio-guided parathyroidectomy. The intact parathyroid hormone assays have greatly added to the detection of normal and abnormal functioning glands, hence better surgical outcomes.

Early-phase technetium-99m sestamibi scintigraphy can improve preoperative localization in primary hyperparathyroidism

BACKGROUND

In hyperparathyroidism, dual-phase technetium-99m sestamibi scintigraphy is important for parathyroid adenoma localization. We hypothesized that reviewing early-phase scans can increase localization in patients with primary hyperparathyroidism (PHPT).

METHODS

We reviewed our prospectively maintained database for patients with sestamibi scans before parathyroidectomy for PHPT from 2001 to 2011. Early-phase scans were read and compared with the location of the gland(s) removed at operation.

RESULTS

Of 902 patients identified, radiologists read 693 scans as positive. Of 209 negative scans, 141 (67%) were positive in the early phase; 135 (96%) correctly identified the side of the adenoma. Using radiologist reads, 35% of patients with negative scans and 41% of patients with falsely localized glands required bilateral exploration compared with 5% of patients with correctly localized glands.

CONCLUSIONS

A review of early scans in patients with negative imaging increases accurate adenoma localization and allows for minimally invasive operations in more patients.

Intrathyroidal parathyroid glands: small, but mighty (a Napoleon phenomenon)

BACKGROUND

Intrathyroidal parathyroid adenomas (ITPAs) are a rare entity. The aim of this study is to describe the experience of 2 endocrine surgery centers and to distinguish characteristics of intrathyroidal parathyroid adenoma and nonintrathyroidal parathyroid adenomas.

METHODS

We included patients who had undergone operations for primary hyperparathyroidism who had intrathyroidal parathyroid adenomas. Patients with single intrathyroidal parathyroid adenomas were also compared to age- and sex-matched controls with nonintrathyroidal parathyroid adenomas.

RESULTS

Of 4,868 patients who underwent parathyroidectomy between January 2002 and June 2011, we identified 53 (1%) patients with intrathyroidal parathyroid adenoma. Sestamibi and ultrasound scans correctly identified the adenoma in 35 (70%) and 11 (61%) cases, respectively. Single adenomas were identified in 44 (83%) patients, double adenomas in 4 (8%) patients, and hyperplasia in 5 (9%) patients. Lobectomy was performed in 17 (32%) patients; enucleation was used in 36 (68%) patients. Cure was achieved in all patients and no patients experienced a recurrence. Patients with single intrathyroidal parathyroid adenomas had significantly smaller glands than patients with nonintrathyroidal parathyroid adenomas (325 ± 47 vs 772 ± 61 mg; P < .0001); however, no significant difference was identified between the groups with regard to demographics, symptoms, preoperative laboratory values, or outcomes.

CONCLUSION

Single intrathyroidal parathyroid adenomas are smaller than nonintrathyroidal parathyroid adenomas, but patients with intrathyroidal parathyroid adenomas present with similar laboratory values and symptoms. Recognition of this rare entity can lead to a successful surgical outcome.

Is minimally invasive parathyroidectomy associated with greater recurrence compared to bilateral exploration? Analysis of more than 1,000 cases

BACKGROUND

The durability of minimally invasive parathyroidectomy (MIP) has been questioned, and some advocate for routine open parathyroidectomy (OP). This study compared outcomes between patients treated with MIP compared with OP for primary hyperparathyroidism (PHPT).

METHODS

A retrospective review was performed to identify cases of PHPT with single adenomas (SA) between 2001 and 2011. Operations were classified as OP when both sides were explored. Kaplan-Meier estimates were plotted and compared by the log-rank test.

RESULTS

We analyzed 1,083 patients with PHPT with SA; 928 (85.7%) were MIP and 155 (14.3%) were OP. There was no difference in the rates of persistence (0.2% MIP vs 0% OP, P = .61) or recurrence (2.5% MIP vs 1.9% OP, P = .68) between the 2 groups. The Kaplan-Meier estimates did, however, began to separate beyond 8 years' follow-up. The OP group did experience a greater incidence of transient hypocalcemia postoperatively (1.9% vs 0.1%, P = .01).

CONCLUSION

MIP appears equivalent to OP in single-gland disease. Although patients undergoing OP experienced more transient hypocalcemia, patients undergoing MIP appear to have a greater long-term recurrence rate. Therefore, proper patient selection and counseling of these risks is necessary for either approach.

Improved localization of sestamibi imaging at high-volume centers

OBJECTIVES/HYPOTHESIS

Sestamibi imaging can provide critical information regarding the location of suspected parathyroid adenomas. However, this modality can be challenging to perform and interpret reliably. The impact of experience on the localizing efficacy of sestamibi scanning was assessed.

STUDY DESIGN

Prospective analysis of a consecutive series of patients undergoing parathyroidectomy was undertaken after institutional review board approval was obtained.

METHODS

Patients undergoing parathyroid surgery from October 2003 through June 2011 were considered. Inclusion criteria represented primary surgery for primary hyperparathyroidism, in which a single adenoma was excised and cure obtained. Sestamibi scan results, performed at our institution and at outside imaging centers, were compared to intraoperative findings.

RESULTS

There were 389 parathyroidectomies performed; 188 patients met inclusion criteria. Fifty-four patients had sestamibi scans performed at outside institutions; 36 (67%) were localizing and 18 (33%) were nonlocalizing. Among localizing studies, half identified the correct quadrant and half recognized the correct side. At our institution, 147 patients underwent sestamibi imaging; 121 (82%) localized and 26 (18%) did not. Among localizing studies, the correct quadrant was reported in 64% and the correct side in 36%. Of the 147 scans performed at our institution, 13 represented repeat scans of patients with nonlocalizing outside scans. All 13 of these localized; six identified the correct quadrant and seven the side of the adenoma.

CONCLUSIONS

A high volume of experience may improve the yield of sestamibi imaging. Repeating this study at a high-volume center when it was nonlocalizing elsewhere may provide useful additional information.

Incidence of concomitant hyperparathyroidism in patients with thyroid disease requiring surgery

BACKGROUND

Thyroid disease and hyperparathyroidism (HPT) are among the most common endocrine disorders, however, their association has not been well established. The aim of the present study was to determine the incidence of concomitant HPT in patients with thyroid disease requiring surgery, because a single definitive surgery should ideally be performed.

METHODS

We retrospectively reviewed a prospectively maintained database of patients who underwent thyroidectomy at a single institution. Data collected included the patients' initial indication for surgery, preoperative workup, and operative findings.

RESULTS

Of the 1,049 patients who underwent thyroidectomy, 56 (5%) had concomitant HPT and underwent simultaneous parathyroidectomy. Of these 56 patients, 36 initially presented with thyroid disease and 20 with HPT. The mean age was 59 ± 2 years, and 79% were women. The mean preoperative calcium and parathyroid hormone levels were elevated at 10.4 ± 0.1 mg/dL and 87 ± 7 pg/mL, respectively. Most of these patients had primary HPT (n = 54, 96%). Of the 36 patients presenting initially with thyroid disease, 26 had an elevated calcium or parathyroid hormone value and were preoperatively diagnosed with HPT. The remaining 10 patients had normal laboratory findings; however, a pathologically enlarged parathyroid gland was found at thyroidectomy. The overall cure rate for HPT within our series was 96%.

CONCLUSION

The incidence of concomitant HPT in patients with thyroid disease requiring surgery is significant at 5%. Recognition of concurrent disease is important, because it allows for a single definitive surgery to treat both pathologies.

Should 'mild primary hyperparathyroidism' be reclassified as 'insidious': is it time to reconsider?

Primary hyperparathyroidism (PHPT) is a common incidental finding on routine biochemical testing, affecting around 1% of the population. The majority of individuals will be asymptomatic at diagnosis, with no evidence of end organ damage, and unless individuals aged <50 years at diagnosis, they are often considered to have 'mild' PHPT, as they do not meet published criteria for parathyroidectomy (PTX). However, there is increasing evidence that 'mild' PHPT is associated with adverse health outcomes. Long-term observational studies describing the natural history of 'mild' PHPT suggest that even though biochemistry may be relatively stable in the majority, bone mineral density (BMD) does decline after approximately 10 years of observation, whereas significant improvements in BMD are seen following PTX. Recent large European record linkage studies of 'mild PHPT' demonstrate significantly increased all-cause and cardiovascular mortality, similar to rates published for patients with PHPT who meet the NIH surgical criteria. 'Mild' PHPT was also associated with increased admissions for nonfatal cardiovascular disease, renal failure, renal stones, fractures, hypertension, psychiatric disease, cancer and diabetes, suggesting that 'insidious' PHPT may be a more appropriate description, or at least that the term 'mild' should be abandoned. Randomized controlled trials (RCTs) have begun to explore the benefits of PTX in this condition, demonstrating improvements in BMD and some psychiatric outcomes at approximately 2 years of follow-up. However, larger, adequately powered, long-term, RCTs will be required to determine whether PTX improves potential long-term morbidity and mortality in patients with PHPT who do not meet standard surgical criteria.