Use Of Intraoperative Parathyroid Hormone Research Articles

Test Minimally Invasive Parathyroidectomy Under Local Cervical Block Anesthesia for Primary Hyperparathyroidism and Parathyroid Adenoma

With both improvement in preoperative parathyroid tumor identification and the use of intraoperative parathyroid hormone (PTH) assay, minimally invasive parathyroidectomy (MIP) is now performed more frequently in patients with primary hyperparathyroidism (pHPT) compared to both historically and to cervical exploration. Still, many institutions are not familiar with performing MIP under regional or local anesthesia. We present such an operation under local cervical block anesthesia.

Use of intraoperative parathyroid hormone measurements during parathyroidectomy to predict postoperative parathyroid hormone levels in patients with renal hyperparathyroidism: meta-analysis.

BackgroundSeveral studies have reported on the use of intraoperative parathyroid hormone (ioPTH) measurements during parathyroidectomy (PTX) for renal hyperparathyroidism (rHPT), but there is no consensus on whether it is helpful and, if so, what protocol should be used. Therefore, the literature was systematically reviewed to assess a correlation between ioPTH and early postoperative parathyroid hormone (PTH) levels in patients undergoing PTX for rHPT, separately for those on dialysis and those with a functioning renal transplant.MethodsA systematic literature search was performed in electronic databases. Quality assessment was performed using the Quality In Prognosis Studies tool. Mean ioPTH values were calculated at different time points and correlated to the postoperative PTH levels within 1 month. Fixed-effect and random-effects models were performed to assess the mean ioPTH levels at 10 or 20 min after resection (T10 and T20). Stratified analyses were performed for patients on dialysis and those with a functioning renal transplant.ResultsOf the 3087 records screened, 14 studies were included, including some 1177 patients; 1091 were on dialysis and 86 had a functioning kidney transplant. Risk of bias was moderate for most studies. For patients on dialysis, T10 and T20 mean ioPTH levels were 32.1 (95 per cent c.i. 24.3 to 39.9) pmol/l and 15.4 (95 per cent c.i. 7.8 to 22.9) pmol/l) in the random effects meta-analysis. Between individual studies, ioPTH ranged from 4.0–65.1 pmol/l at T10 and 8.6–25.7 pmol/l at T20. T10 and T20 ioPTH were 9.6 and 4.1 times the postoperative PTH—after T20 ioPTH stabilized in those on dialysis. In patients with a functioning renal transplant, ioPTH levels seemed to plateau after 10 min and measured 2.6 times the postoperative PTH.ConclusionThere is a strong correlation between ioPTH and early postoperative PTH levels, indicating that ioPTH is potentially a useful instrument during PTX in patients with rHPT. For patients on dialysis, at T20 ioPTH levels have stabilized and are approximately four times the postoperative PTH. Therefore, it is recommended to use ioPTH 20 min after resection in patients on dialysis, which might be longer than necessary for those with a kidney transplant.

Outcomes in patients with and without intraoperative parathyroid hormone testing for primary hyperparathyroidism: A retrospective observational analysis

ObjectivesThe use of intraoperative parathyroid hormone (ioPTH) monitoring has been recommended as an adjunct to improve likelihood of successful parathyroid surgery. We sought to compare the surgical outcomes as well as operative times and associated costs in patients with and without ioPTH in the setting of co-localizing studies for primary hyperparathyroidism. MethodsA retrospective review was conducted of patients undergoing surgery for nonfamilial primary hyperparathyroidism at a single institution from January 2013 to April 2019. Patients with a suspected single adenoma that co-localized on sestamibi and ultrasound were included resulting in 141 patients, of which 110 (78%) had ioPTH testing (group 1) while 31 (22%) did not (group 2). Time driven activity-based cost (TDABC) analysis was performed incorporating physician and staff compensation and anesthetic usage to determine the cost differential between groups. Study DesignRetrospective chart review. ResultsIn group 1, the use of ioPTH prompted re-exploration in 2 patients (1.8%). In both cases, the initial gland identified was normal parathyroid and persistent elevation of ioPTH resulted in additional dissection and removal of the adenoma. All but two group 1 patients had normal post-operative calcium levels at last follow up for an overall success rate of 97.3%. One group 2 patient (3.2%) was found to have recurrent hyperparathyroidism 33 months later with an adenoma identified in the same location as the initial excision. Otherwise all group 2 patients were eucalcemic at last follow-up for an overall success rate of 96.8%. The average time for the procedure in group 1 was 91.7 ± 28.1 minutes compared to 52.3 ± 16.9 minutes in group 2 (p<0.001). Mean TDABC for group 1 was $900.93 ± 261.49 compared to $487.52 ± 157.93 for group 2 (p<0.001). ConclusionsIn patients with co-localizing sestamibi scan and ultrasound and concordant operative findings, the use of ioPTH did not improve the success rate of minimally invasive parathyroid surgery, while increasing operative times and cost.

Use of Intraoperative Parathyroid Hormone in Minimally Invasive Parathyroidectomy for Primary Hyperparathyroidism

Intraoperative parathyroid hormone (ioPTH) is a surgical adjunct that has been increasingly used during minimally invasive parathyroidectomy (MIP). Despite its growing popularity, to our knowledge a meta-analysis comparing MIP with ioPTH vs MIP without ioPTH has not yet been conducted. To evaluate the safety and efficacy of MIP with ioPTH for treatment of primary hyperparathyroidism. A systematic search of the databases PubMed, Embase, Scopus, Web of Science, and Cochrane Collaboration was performed to identify studies that compared MIP with and without ioPTH. Data were analyzed between August and September 2019. Inclusion criteria consisted of randomized clinical trials and observational studies with a retrospective/prospective design, comparing MIP using ioPTH vs MIP not using ioPTH for treatment of primary hyperparathyroidism. Eligible studies had to present odds ratio (OR), risk ratio, or hazard ratio estimates (with 95% CI), standard errors, or number of events necessary to calculate these for the outcome of interest rate. Studies involving patients with secondary or tertiary hyperparathyroidism or those with multiple endocrine neoplasia syndrome were excluded. Two reviewers independently reviewed the literature according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Dichotomous variables were pooled as ORs while continuous variables were compared using weighted mean differences. Quality assessment was performed using the Newcastle-Ottawa Scale. The primary outcome was rate of cure. Secondary outcomes included need for reoperation, need for bilateral neck exploration, morbidity, and length of surgery. A total of 12 studies, involving 2290 patients with primary hyperparathyroidism, were eligible for inclusion. The median (SD) age of participants was 60.1 (11.8) years and 77.3% of participants were women. The median Newcastle-Ottawa score was 7. Patients who underwent MIP with ioPTH had higher cure rates (OR, 3.88; 95% CI, 2.12-7.10; P < .001). There was a greater need for reoperation in the group of patients who had surgery without ioPTH (OR, 0.40; 95% CI, 0.19-0.86; P = .02). There was a trend toward longer operating times/increased duration of surgery in the ioPTH group; however, this did not reach statistical significance (weighted mean difference, 21.62 minutes; 95% CI, -0.93 to 44.17 minutes; P = .06). The use of ioPTH was associated with higher rates of bilateral neck exploration (OR, 3.55; 95% CI, 1.27-9.92; P = .02). Use of ioPTH is associated with higher cure rates for patients with primary hyperparathyroidism undergoing MIP. Minimally invasive parathyroidectomy performed without ioPTH is associated with less conversion to bilateral neck exploration at initial surgery but with lower cure rates and an increased risk for reoperation. PROSPERO identifier: CRD42020148588.

Critical analysis of the intraoperative parathyroid hormone decrease during parathyroidectomy for secondary and tertiary hyperparathyroidism

BackgroundThis study aims to determine whether intraoperative parathyroid hormone monitoring helps to predict early surgical outcomes in patients with renal hyperparathyroidism and evaluate the impact on decision making during surgery. MethodsA prospective study was conducted. Serial samples of the intraoperative parathyroid hormone were collected; 2 of these were taken before the excision, and 2 were taken after the planned parathyroid resection (10 minutes and 15 minutes). We tested the criterion of an intraoperative parathyroid hormone percentage decay ≥80% of the highest value of the basal samples as a predictor of success. ResultsOf the 228 patients, parathyroidectomy achieved success in 92.1%. In patients with secondary hyperparathyroidism, the failure group showed a tendency to stabilize or even increase the intraoperative parathyroid hormone values from the 10-minute measure (577 pg/mL) to the 15-minute measure (535 pg/mL) (P = .903). Conversely, intraoperative parathyroid hormone continued to drop in those with a successful outcome: 245 pg/mL (10 minutes) and 206 pg/mL (15 minutes) (P < .001). The failure group had a significantly lower percentage decay (P < .001) from baseline when compared with the success group. The intraoperative parathyroid hormone influenced the surgical management in up to 7% of the cases. The intraoperative parathyroid hormone dosage method showed an accuracy of 86%, a sensitivity of 88%, and specificity of 67%. ConclusionIn patients with renal hyperparathyroidism undergoing parathyroidectomy, the use of intraoperative parathyroid hormone may help to predict an early therapeutic outcome with high sensitivity and accuracy by indicating the operation's success when there is an 80% reduction of baseline intraoperative parathyroid hormone 15 minutes after removal of the enlarged glands, an associated continuous decrease in serum intraoperative parathyroid hormone levels between 10 and 15 minutes, and achievement of plasma target values <500 pg/mL.

Surgical treatment in patients with single and multiple gland primary hyperparathyroidism with the use of intraoperative parathyroid hormone monitoring: extensive single-center experience.

To evaluate a single-center extensive experience and effectiveness in surgical treatment of primary hyperparathyroidism (pHPT) with the use of rapid intraoperative parathyroid hormone (ioPTH) monitoring in patients with single gland (SGpH) or multiple gland (MGpH) disease. This retrospective, single-center cohort study included 214 patients with pHPT treated from January 2010 to June 2017. In total, 172 patients fulfilled the inclusion criteria having at least one preoperative localization image study and measurement of ioPTH. Statistical analysis was made by the chi-square test and Student's t tests. Of the 172 patients, 146 were women (85%) and 26 men (15%), with a mean age of 56.9years; 153 (89%) had SGpH and 19 (11%) MGpH. The mean follow-up was 41.8months. A total of 153 surgical procedures were performed as minimal invasive parathyroidectomy (MIP) based on a SGpH diagnosis; operative success was achieved in 150 cases (98%), according to ioPTH concentrations. The remainder (19 procedures) were performed as bilateral neck exploration (BNE) based on a MGpH diagnosis; operative success was achieved in 16 cases (84%). ioPTH correctly modified the initially planned operation in 26.3% of patients with MGpH. ioPTH enables the surgical treatment of patients with pHPT with focused approaches and excellent results, as it helps the surgeon to identify cases of MGpH. ioPTH adds value to cases where preoperative imaging failed to detect the affected gland or the results are inconclusive. According to the literature, its application seems to be of marginal benefit in cases in which there are two concordant preoperative imaging studies.

Intraoperative Parathyroid Hormone Monitoring in Parathyroidectomy for Tertiary Hyperparathyroidism

BackgroundTertiary hyperparathyroidism (THPT) is characterized by hypercalcemia and hyperparathyroidism after renal allograft. Limited data exist regarding the use of intraoperative parathyroid hormone (IOPTH) for THPT. We examined our series of parathyroidectomies performed for THPT to determine clinical outcomes with respect to IOPTH. Materials and methodsPatients who underwent parathyroidectomy for THPT (1999-2017) were identified for inclusion. Retrospective chart review was performed. Cure was defined as eucalcemia ≥6 mo after surgery. Statistical analysis was performed. ResultsOf 41 patients included in the study, 41% (n = 17) were female. The median duration of dialysis before renal allograft was 34 mo (interquartile interval [IQI]:6-60). Preoperatively, the median calcium level was 10.4 mg/dL (IQI:10.0-11.2), median parathyroid hormone was 172 pg/mL (IQI:104-293), and renal function was minimally abnormal with median glomerular filtration rate 58 mL/min/1.73 m2 (IQI:49-71). At surgery, the median final IOPTH was 40 pg/mL (IQI:29-73), and median decrease in IOPTH was 78% (IQI:72-87), with 88% (n = 36) of patients demonstrating >50% decrease. Median calcium level ≥6 mo after surgery was 9.4 mg/dL (IQI:8.8-9.7), and only one patient had recurrent hypercalcemia. Failure to achieve >50% decrease in IOPTH was not significantly associated with recurrent hypercalcemia (P = 1.000). With a median follow-up time of 41 mo (IQI:25-70), only three patients had graft failure. The positive predictive value of IOPTH for cure was 89% (95% confidence interval: 0.752-0.971), with 0% negative predictive value and 87% accuracy (95% confidence interval: 0.726-0.957). ConclusionsSubtotal parathyroidectomy is a successful operation with durable cure of THPT. IOPTH fails to predict long-term cure in THPT despite minimally abnormal renal function.

Focused Parathyroidectomy Using Accurate Preoperative Imaging and Intraoperative PTH: Tertiary Care Experience.

Introduction:The cure rate after focused parathyroidectomy (FP) is dependent upon two critical adjuncts- concordant preoperative imaging and intraoperative parathyroid hormone (PTH), a technique which can reliably determine whether any other hyperfunctioning gland or glands are still present after resection of the lesion shown by imaging. We wanted to see the cure rate of FP by using these two adjuncts. We also sought to discern whether utilizing the central lab rapid PTH assay will lead to wider acceptance of this FP with intraoperative PTH in resource-constrained countries. This analysis was also undertaken to find out cost-effective way of doing intraoperative PTH by minimizing the samples for intraoperative PTH study.Result:Data were collected on 83 patients with sporadic primary hyperparathyroidism (PHPT) who underwent parathyroidectomy in two tertiary centers between '2009 and 2017'. A total of 75 patients had concordant imaging, while seven had discordant imaging. The sensitivity and specificity of intraoperative PTH in FP was 100%. All the 78 patients who had fall in intraoperative PTH (50%) at 10 min also had fall of more than 50% at 5 min except one patient (98.7%).Conclusion:We strongly advocate routine use of intraoperative PTH in all patients undergoing minimally invasive parathyroidectomy, as this adjunct offers maximum safety for the patient and confidence for the surgeon. Cost can be minimized by utilizing the central laboratory and reducing the number of samples.

Surgical Management of Primary Hyperparathyroidism in the Era of Focused Parathyroidectomy: A Study in Tertiary Referral Centre of North India.

Background:Despite the benefits of focused parathyroidectomy (FPTx), few studies have questioned its durability with lower long-term cure rates than bilateral or conventional parathyroidectomy (CPTx). The objective of this study is to bring out the information on the type of surgical management versus cure rate, recurrence, and role of intra-operative parathyroid hormone (IOPTH) level monitoring of PHPT patients.Material and Methods:This was a retrospective study of all PHPT patients treated at our center based on operative approach (CPTx vs FPTx) or use of IOPTH. Treatment failure was divided into persistent or recurrent disease, based on documentation of hypercalcemia in combination with an inappropriate PTH within 6 months or more of surgery, respectively.Results:Overall, 50.78% patients underwent CPTx and 49.32% FPTx. 29 FPTx were converted to CPTx. Intention to treat analysis between CPTx and FPTx showed that the persistence rate was not statistically different at 2.54% and 4%, respectively (P = 0.98). Furthermore, when the persistence rate was scrutinized by a treatment received (TR) instead of ITT analysis, the persistence rate was higher for the patients who underwent TR-CPTX than for the patients subjected to TR-FPTX (3.22% vs 1.08%) but not significant statistically. We further analyzed the outcome of FPTx with IOPTH (n = 213) and FPTx without IOPTH (n = 28). The outcome did not differ between two groups statistically.Conclusion:FPTx yields a similar success rate as compared to CPTx even in symptomatic PHPT patients and can be performed safely even without intra-opeartive adjunct IOPTH in selected patients.

Management of undetectable and lost parathyroid adenoma

The introduction of new technologies and the improvement of localization diagnostics have led to a change of strategy in the surgery of primary hyperparathyroidism (pHPT). Focused approach to a preoperatively located parathyroid adenoma and the use of intraoperative parathyroid hormone (IOPTH) determination improve the quality of the surgical procedure and reduce morbidity. Nevertheless, the success rate of approximately 95–99% in the initial intervention could not be improved by the new or further developed technologies. The parathyroid adenoma, which cannot be found intraoperatively, is still a surgical problem today. Advances in preoperative imaging and use of IOPTH levels are even more important for the approach to re-operative parathyroidectomy. Diagnosis of persistent and recurrent pHPT is dependent on the quality and duration of follow-up, as well as the availability of biochemical data in centralized repositories. The consequence are the high cost to the patient of missed or inadequate initial operation, physical effects of remaining hyperparathyroid, additional time off work, potentially invasive localization testing, reoperative surgery, increased risk of complication and expense. To reduced failure rate is essential the correct indication, timing and type of surgery, availability of intact parathyroid hormone (iPTH) assay and the improvement of preoperative localizing studies.

Intraoperative Parathyroid Hormone Monitoring in Guiding Adequate Parathyroidectomy.

Background:Parathyroidectomy has been traditionally performed through bilateral neck exploration (BNE). However, with the use of intraoperative parathyroid hormone (IOPTH) assay along with preoperative localization studies, focused parathyroidectomy can be performed with good surgical success rate, multiglandular disease can be predicted, and hence recurrence and surgical failure can be prevented. Furthermore, it predicts eucalcemia in the postoperative period. The aim of this study was to evaluate the usefulness of IOPTH assay in guiding adequate parathyroidectomy in patients of primary hyperparathyroidism.Materials and Methods:Between year 2015 and 2017, 45 patients of primary hyperparathyroidism underwent parathyroidectomy with IOPTH assay employed as an intraoperative tool to guide the surgical procedure. Blood samples were collected: (1) at preincision time, (2) preexcision of gland, (3) 5-min postexcision of gland, and (4) 10-min postexcision of gland. On the basis of the Irvin criterion, an intraoperative PTH drop >50% from the highest either preincision or preexcision level after parathyroid excision was considered a surgical success. Otherwise, BNE was performed and search for other parathyroid glands done.Results:Ten-min postexcision PTH levels dropped >50% in 34 (75.6%) patients. True positive among them were 31 (68.8%), true negative 8 (17.7%), false positive 3 (6.6%), and false negative 3 (6.6%). We performed focused exploration at the outset in 40 (88.9%) patients and bilateral exploration for five patients as guided by preoperative localizing studies. Hence, IOPTH was helpful in guiding further exploration in 8 (17.7%) patients and prevented further exploration in 32 (71.1%) patients and also was able to predict eucalcemia in 97.7% patients at 6 months. Thus, IOPTH was able to obviate or to ask for additional procedure in 88.8% of patients. However, in three (6.6%) patients, IOPTH would guide unnecessary exploration and in equally, that is, three (6.6%) patients may require reoperation for unidentified parathyroids.Conclusion:IOPTH in adjunct with other localizing studies is very helpful for carrying out successful parathyroidectomy in uniglandular disease and predicting postoperative eucalcemia. However, more importantly, its role is valuable in equivocal imaging, in such cases, it prevents unnecessary exploration or helps in adequate parathyroidectomy.

Intraoperative Parathyroid Hormone is a Valuable Indicator of Long Term Cure in Primary Hyperparathyroidism

Background: The use of intraoperative parathyroid hormone (ioPTH) during surgery for primary hyperparathyroidism (PHPT) has become widely available as a tool to monitor the success of the procedure. The aim of our study was to correlate the decrease of ioPTH with long term outcome in patients with PHPT. Methods: During a 10 year period, in 137 consecutive patients with PHPT, serum PTH was measured during surgery at baseline and 5, 10 and 20 minutes after excision of the suspected parathyroid gland. Surgery was considered successful if a 50% drop in ioPTH was observed after 10 minutes. Two groups were defined - with normal (I) and above normal (II) PTH after 10 minutes. Calcium and PTH were monitored at 1.5, 3, 6 and 12 months of follow-up. Results: Group I had significantly lower median weight of glands (1.4 vs 3.0 g), maximum pre-operative calcium (11.1 vs 11.7 mg/dL) and ioPTH at 10 minutes (30.1 vs 124.9 pg/mL) than group II - P < 0.05. Serum PTH levels at 3 and 6 months of follow-up were also significantly lower in group I than group II (55.0 vs 124.5 pg/mL and 55.9 vs 83.1 pg/mL, respectively) - P < 0.05. At 6 months, 74.3% of the patients in group I presented normal calcium and PTH, whereas in group II normal calcium and high PTH was the predominant pattern (59.1%) - P = 0.01. Conclusions: Obtaining normalization of ioPTH during surgery is important in addition to the classic criterion of 50% decrease from baseline to predict cure of PHPT. doi: http://dx.doi.org/10.4021/jem189w

Surgery for Primary Hyperparathyroidism in Patients with Preoperatively Negative Sestamibi Scan and Discordant Imaging Studies: The Usefulness of Intraoperative Parathyroid Hormone Monitoring

The aim of this study was to evaluate the impact of intraoperative parathyroid hormone (PTH) monitoring on surgical strategy, intraoperative findings, and outcome in patients with negative sestamibi scintigraphy and with discordant imaging studies. We divided our 175 patients into 3 groups: group A was methoxyisobutylisonitrile (MIBI)-positive and ultrasonography positive and was concordant (114 patients), group B was MIBI-positive and ultrasonography-negative (50 patients), and group C was MIBI—and ultrasonography-negative (11 patients). The overall operative success was 99.12% in group A, 98% in group B, and 90.91% in group C, with an incidence of multiglandular disease of 3.5% in group A, 12% in group B, and 9.09% in group C. Intraoperative PTH monitoring changed the operative management in 2.63% of patients in group A and 14% in group B. The use of intraoperative PTH achieves to obtain excellent results in the treatment of primary hyperparathyroidism in high-volume centers, even in the most difficult cases, during MIBI-negative and discordant preoperative imaging studies.

Point-of-care rapid intraoperative parathyroid hormone assay of needle aspirates from parathyroid tissue: a substitute for frozen sections

Background The intraoperative parathyroid hormone (IOPTH) assay is an important tool that facilitates targeted parathyroidectomy and may increase surgical cure rates. We sought to evaluate the utility of a point-of-care assay to distinguish parathyroid adenomas from nonparathyroid tissues, which can sometimes pose a challenge during parathyroidectomy and is commonly achieved with the use of frozen sections. We hypothesized that point-of-care rapid IOPTH assays of needle aspirates from suspected adenomas would be faster and equal in accuracy to frozen sections. Methods Parathyroid and nonparathyroid lesions were excised, and the tissues were needle aspirated, diluted in saline, and submitted to a rapid IOPTH assay located in the operating room. Frozen sections were simultaneously sent for analysis. The time intervals to result availability were tracked and compared using a paired t test. Results Point-of-care IOPTH assays of needle aspirates were available in a mean (±SD) of 11.6 ± 1.5 minutes compared to 18.7 ± 4.0 minutes for frozen sections ( P = .005). The findings were concordant 100% of the time for both parathyroid (mean parathyroid hormone [PTH] > 3338.9 pg/mL) and parathyroid tissues (mean PTH = 8.7 pg/mL). Conclusion Point-of-care IOPTH assay of needle aspirates is an accurate method of distinguishing parathyroid from nonparathyroid tissues. It is suggested that this would be particularly useful in instances where use of IOPTH is planned for assessment of a drop in serum PTH.

Intraoperative parathyroid hormone monitoring to determine long‐term success of total parathyroidectomy for secondary hyperparathyroidism

Use of intraoperative parathyroid hormone (ioPTH) monitoring during total parathyroidectomy for secondary hyperparathyroidism is common, although its ability to predict long-term normoparathyroid state is not known. Prospective evaluation of 57 consecutive patients undergoing total parathyroidectomy for renal hyperparathyroidism with ioPTH monitoring and follow-up PTH assays were used to categorize the patients into 3 groups: success, adequate biochemical control, and failure. There was no statistically significant difference in percentage reduction of ioPTH between the 3 groups (p = .07), although there was a moderate negative correlation between percentage reduction of ioPTH and percentage reduction of PTH at follow-up (R = 0.57). When used under current guidelines, ioPTH monitoring is of no use in predicting long-term cure for these patients because it does not predict success. Patients that undergo total parathyroidectomy are required to have long-term calcium and PTH assay follow-up because normoparathyroidism cannot be assumed. Using the regression equation calculated, success may be predicted for future patients.

Parathyroid Carcinoma: Current Understanding and New Insights into Gene Expression and Intraoperative Parathyroid Hormone Kinetics

Parathyroid carcinoma is an indolent but ultimately life-threatening malignancy. Due to the lack of definitive diagnostic markers and overlapping clinical features of benign primary hyperparathyroidism (PHPT), this disease is often misdiagnosed as parathyroid adenoma. Therefore, a high index of suspicion preoperatively and early intraoperative recognition with en bloc surgical resection are crucial for favorable outcome. Owing to the rarity of the disease, little is known about the molecular pathogenesis of parathyroid carcinoma. Here, we review the literature to present current understanding of the disease and provide new information on gene expression and use of intraoperative parathyroid hormone (PTH) monitoring in the surgical management of this rare malignancy. Specifically, using microarray transcriptome analysis of an unequivocal case of parathyroid carcinoma and a biopsy from the same patient's normal parathyroid gland, we identify APP, CDH1, KCNJ16, and UCHL1 as differentially expressed genes in parathyroid carcinoma. Further, using case records from four cases of unequivocal parathyroid carcinoma, we compared intraoperative PTH kinetics of these patients to 475 patients with benign PHPT, and show that intraoperative PTH monitoring is accurate in predicting postoperative normocalcemia in initial en bloc operations for parathyroid carcinoma.

Intraoperative adjuncts in surgery for primary hyperparathyroidism

This paper is a review of the evidence base to produce recommendations for the use of intraoperative parathyroid hormone (PTH), radioguided parathyroidectomy (RGP), methylene blue (MB), frozen section, and intraoperative neuromonitoring during surgery for primary hyperparathyroidism (PHPT). A Medline keyword search of English-language articles led to the production of a draft document, subsequently revised by committee, containing levels of evidence and the grading of recommendations as proposed by the Agency for Healthcare Research and Quality. Literature review provides the basis for clear recommendations on the use of intraoperative PTH at surgery for PHPT. There is little evidence to support the use of RGP, MB, routine frozen section, and intraoperative neuromonitoring.

Reoperative parathyroid surgery

Reoperative parathyroid surgery can be technically challenging and exposes the patient to a higher risk of complications than initial parathyroidectomy. Initial surgical failure can be avoided by thorough, bilateral exploration by an experienced parathyroid surgeon or by the use of intraoperative parathyroid hormone (PTH) monitoring if a limited exploration is planned. Before undertaking a reoperation for hyperparathyroidism the patient must be fully reevaluated including a reassessment of the need for surgery, a review of all previous surgical and pathology reports, and the performance of imaging studies to identify the location of the missing gland. An understanding of parathyroid embryology and anatomy helps identify possible locations of missing glands. The specific surgical approach is dictated by the anticipated location of the abnormal gland. Intraoperative PTH monitoring can limit the extent of reoperative surgery. Recurrent laryngeal nerve monitoring can help decrease the risk of complications.

The use of pre-operative imaging and intraoperative parathyroid hormone level to guide surgical management of tertiary hyperparathyroidism from X-linked hypophosphatemic rickets: a case report

IntroductionTo describe the use of combined preoperative imaging and intraoperative parathyroid hormone as a novel approach in the surgical management of a patient with tertiary hyperparathyroidism associated with X-linked hypophosphatemic rickets.Case presentationWe present the first documented description of combined preoperative imaging and intraoperative parathyroid hormone as well as a review of the literature surrounding the surgical management of tertiary hyperparathyroidism in the setting of X-linked hypophosphatemic rickets.A 23 year-old female with X-linked hypophosphatemic rickets and renal impairment presented with symptomatic hypercalcemia and tertiary hyperparathyroidism. She had failed medical management and presented for surgical evaluation. Technitium-99 m Sestamibi SPECT imaging and parathyroid ultrasound were used to localize the enlarged parathyroid glands preoperatively. Intraoperative findings correlated well with pre-operative imaging. She underwent successful subtotal parathyroidectomy for four-gland hyperplasia, using intraoperative parathyroid hormone guidance. Despite severe post-operative bone hunger, her serum calcium normalized and she experienced resolution of her preoperative symptoms.ConclusionX-linked hypophosphatemic rickets is an uncommon disorder of phosphate metabolism resulting in bone deformity. Patients are predisposed to the development of secondary hyperparathyroidism due to chronic vitamin D supplementation which may progress to tertiary hyperparathyroidism with autonomous parathyroid function. Preoperative evaluation with Technitium-99 m Sestamibi SPECT and ultrasound imaging, as well as the use of intraoperative parathyroid hormone are effective in guiding surgical resection. Subtotal parathyroidectomy with cryopreservation is indicated to produce operative cure and limit the risk of recurrence. Although these patients are susceptible to severe postoperative bone hunger, appropriate supplementation with intravenous and oral calcium can minimize hypocalcemic symptoms.

Reoperative parathyroidectomy in 228 patients during the era of minimal-access surgery and intraoperative parathyroid hormone monitoring

Background Reoperative parathyroidectomy (R-PTX) in primary hyperparathyroidism (1HPT) has increased failure rates and morbidity. This study evaluated R-PTX during the era of minimal-access PTX with intraoperative parathyroid hormone (IOPTH) monitoring. Methods Two thousand sixty-five patients with 1HPT who underwent PTX were assessed for R-PTX. Preoperative studies, operative findings, and outcomes were evaluated. Results Two hundred twenty-eight patients underwent 236 R-PTX procedures. Imaging performed included sestamibi (89%), ultrasound (US; 56%), computed axial tomography/magnetic resonance imaging (5%), and selective venous sampling (1%). Sestamibi was more sensitive than US (84% vs 68%). Curative surgery was performed in 89% of patients. IOPTH was 99% sensitive. There was no relationship between cure and the following parameters: preoperative calcium or PTH levels, persistent or recurrent disease, or use of IOPTH. Solitary gland disease and a single previous operation were associated with increased likelihood of cure ( P = .06). Hypoparathyroidism was decreased using IOPTH monitoring (2% vs 9%). One patient had recurrent laryngeal nerve palsy. Conclusions R-PTX can be performed effectively with minimal complications. IOPTH is an accurate predictor of cure and may decrease the frequency of permanent hypoparathyroidism.