Secondary hyperparathyroidism: diagnosis of site of recurrence

Surgical Management of Secondary and Tertiary Hyperparathyroidism

Secondary hyperparathyroidism (SHPT) often arises from kidney disease and is characterized by elevated parathyroid hormone (PTH) levels. The reported optimal PTH level to balance the compensatory physiologic response in SHPT with the pathologic morbidity and mortality has changed over time with our evolving understanding. Parathyroidectomy for kidney-related hyperparathyroidism requires consideration of the patient's dialysis status, potential for kidney transplantation, and medical history. Extent of parathyroidectomy and intraoperative decision-making requires consideration to maximize cure with the risk of permanent hypoparathyroidism. Parathyroidectomy for kidney-related hyperparathyroidism can provide a reduction in morbidity, mortality, and improved kidney allograft function and survival.

Treatment for secondary hyperparathyroidism focusing on parathyroidectomy

Secondary hyperparathyroidism (SHPT) is a major problem for patients with chronic kidney disease and can cause many complications, including osteodystrophy, fractures, and cardiovascular diseases. Treatment for SHPT has changed radically with the advent of calcimimetics; however, parathyroidectomy (PTx) remains one of the most important treatments. For successful PTx, removing all parathyroid glands (PTGs) without complications is essential to prevent persistent or recurrent SHPT. Preoperative imaging studies for the localization of PTGs, such as ultrasonography, computed tomography, and 99mTc-Sestamibi scintigraphy, and intraoperative evaluation methods to confirm the removal of all PTGs, including, intraoperative intact parathyroid hormone monitoring and frozen section diagnosis, are useful. Functional and anatomical preservation of the recurrent laryngeal nerves can be confirmed via intraoperative nerve monitoring. Total or subtotal PTx with or without transcervical thymectomy and autotransplantation can also be performed. Appropriate operative methods for PTx should be selected according to the patients' need for kidney transplantation. In the case of persistent or recurrent SHPT after the initial PTx, localization of the causative PTGs with autotransplantation is challenging as causative PTGs can exist in the neck, mediastinum, or autotransplanted areas. Additionally, the efficacy and cost-effectiveness of calcimimetics and PTx are increasingly being discussed. In this review, medical and surgical treatments for SHPT are described.

Long-Term Outcomes of Parathyroid Autografts in Primary Hyperparathyroidism

Context

Autologous implantation of parathyroid tissue is frequently utilized after parathyroidectomy in patients with heritable forms of primary hyperparathyroidism (PHPT). Data on long-term functional outcome of these grafts is sparse.

Objective

To investigate long-term outcomes of parathyroid autografts.

Methods

Retrospective study of patients with PHPT who underwent parathyroid autografts from 1991 to 2020.

Results

We identified 115 patients with PHPT who underwent 135 parathyroid autografts. Median follow-up duration since graft was 10 (4-20) years. Of the 111 grafts with known functional outcome, 54 (49%) were fully functional, 13 (12%) partially functional, and 44 (40%) nonfunctional at last follow-up. Age at time of graft, thymectomy prior to autograft, graft type (delayed vs immediate), or duration of cryopreservation did not predict functional outcome. There were 45 (83%) post-graft PHPT recurrences among 54 fully functional grafts at a median duration of 8 (4-15) years after grafting. Surgery was performed in 42/45 recurrences, but cure was attained in 18/42 (43%) only. Twelve of 18 (67%) recurrences were graft-related while remaining 6 (33%) had a neck or mediastinal source. Median time to recurrence was 16 (11-25) years in neck or mediastinal source vs 7 (2-13) years in graft-related recurrences. Median parathyroid hormone (PTH) gradient was significantly higher at 23 (20-27) in graft-related recurrence vs 1.3 (1.2-2.5) in neck or mediastinal source (P = .03).

Conclusions

Post-graft recurrence of PHPT occurs frequently within the first decade after graft and is challenging to localize. Time to recurrence after graft is significantly shorter and PTH gradient higher for graft-related recurrence. Clinical Trial Number: NCT04969926.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Secondary and Tertiary Renal Hyperparathyroidism

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate treatment of secondary (SHPT) and tertiary (THPT) renal hyperparathyroidism.

BACKGROUND

Hyperparathyroidism is common among patients with chronic kidney disease, end-stage kidney disease, and kidney transplant. The surgical management of SHPT and THPT is nuanced and requires a multidisciplinary approach. There are currently no clinical practice guidelines that address the surgical treatment of SHPT and THPT.

METHODS

Medical literature was reviewed from January 1, 1985 to present January 1, 2021 by a panel of 10 experts in SHPT and THPT. Recommendations using the best available evidence was constructed. The American College of Physicians grading system was used to determine levels of evidence. Recommendations were discussed to consensus. The American Association of Endocrine Surgeons membership reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines present the epidemiology and pathophysiology of SHPT and THPT and provide recommendations for work-up and management of SHPT and THPT for all involved clinicians. It outlines the preoperative, intraoperative, and postoperative management of SHPT and THPT, as well as related definitions, operative techniques, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Preoperative and Perioperative Care, Surgical Planning and Parathyroidectomy, Adjuncts and Approaches, Outcomes, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal management of secondary and tertiary renal hyperparathyroidism.

Total parathyroidectomy with forearm autotransplantation in secondary hyperparathyroidism patients: analysis of muscle, subcutaneous and muscle + subcutaneous method

Background

Forearm autotransplantation after parathyroidectomy has turned into the standard method for secondary hyperparathyroidism (SHPT) treatment in chronic kidney disease patients. Our study aimed to explore the effects of three methods including muscle, subcutaneous and muscle + subcutaneous transplant methods on SHPT.

Methods

Seventy five SHPT patients were enrolled and assigned into the muscle + subcutaneous (M + S) (n = 26), muscle (M) (n = 35), and subcutaneous (S) (n = 14) groups. The operation efficacy evaluation included preoperative and postoperative biological characteristics such as parathyroid hormone (PTH), serum phosphorus, serum calcium and alkaline phosphatase (ALP). The data were recorded from pre-operation time point to 1, 2, 3, 6, 12, 18, 24 month (mo) postoperation periods. After operation, short-form health survey (SF-36) scores was made for life quality identification at 1, 2, 3, 6, 12, 24 time points. Symptoms about SHPT including bone pain, fracture, pruritus, and coronary artery calcification were followed-up based on the scale.

Results

Compared with the preoperative record, all the M + S, M, and S groups showed postoperative decreased levels of PTH, serum phosphorus, serum calcium, calcium-phosphorus. In M + S group, the PTH and serum calcium level kept more steady compared with the M and S groups during a 24 mo duration observation. After this, a SF-36 score scale which represents the life quality show M + S group got more scores at 3, 6, 12, 18 and 24 mo points. At last, the incidence of SHPT associated symptoms including Bone pain, Fracture, Pruritus, and Coronary artery calcification in M + S group were decreased compared with M and S groups at 1, 3, 6, 12 and 24 mo post-operation time points.

Conclusion

M + S seems to be an efficient method for medical treatment of SHPT patients in the control of PTH and serum calcium. This mixed transplant strategy improves the biochemical characterizes compared with M and S groups in SHPT patients. Furthermore, the M + S method make beneficial on clinical outcomes and life quality of patients.

Intact parathyroid hormone levels localize causative glands in persistent or recurrent renal hyperparathyroidism: A retrospective cohort study

Persistent or recurrent renal hyperparathyroidism may occur after total parathyroidectomy and transcervical thymectomy with forearm autograft under continuous stimulation due to uremia. Parathyroid hormone (PTH) levels may reflect persistent or recurrent renal hyperparathyroidism because of the enlarged autografted parathyroid glands in the forearm or remnant parathyroid glands in the neck or mediastinum. Detailed imaging requires predictive localization of causative parathyroid glands. Casanova and simplified Casanova tests may be convenient. However, these methods require avascularization of the autografted forearm for >10 min with a tourniquet or Esmarch. The heavy pressure during avascularization can be incredibly painful and result in nerve damage. An easier method that minimizes the burden on patients in addition to predicting the localization of causative parathyroid glands was developed in this study. Ninety patients who underwent successful re-parathyroidectomy for persistent or recurrent renal hyperparathyroidism after parathyroidectomy between January 2000 and July 2019 were classified according to the localization of causative parathyroid glands (63 and 27 patients in the autografted forearm and the neck or mediastinum groups, respectively). Preoperatively, intact PTH levels were measured from bilateral forearm blood samples following a 5-min avascularization of the autografted forearm. Cutoff values of the intact PTH ratio (intact PTH level obtained from the non-autografted forearm before re-parathyroidectomy/intact PTH level obtained from the autografted forearm before re-parathyroidectomy) were investigated with receiver operating characteristic curves to localize the causative parathyroid glands. Intact PTH ratios of <0.310 with an area under the curve (AUC) of 0.913 (95% confidence interval [CI]: 0.856-0.970; P < 0.001) and >0.859 with an AUC 0.744 (95% CI: 0.587-0.901; P = 0.013) could predict causative parathyroid glands in the autografted forearm and the neck or mediastinum with diagnostic accuracies of 81.1% and 83.3%, respectively. Therefore, we propose that the intact PTH ratio is useful for predicting the localization of causative parathyroid glands for re-parathyroidectomy.

Surgical Management of Secondary Hyperparathyroidism

Secondary hyperparathyroidism (SHPT) affects a majority of patients with chronic kidney disease (CKD) of stage 3 or worse. Despite the development of calcimimetics and their effectiveness in treating SHPT, many patients continue to fail medical management and should be referred to a parathyroid surgeon. In this narrative review, we summarize the indications for surgical referral, preoperative planning, intraoperative strategies to guide resection, and postoperative management. In the absence of universal guidelines, it can be difficult to determine when it is appropriate to make this referral. The majority of studies evaluating parathyroidectomy (PTX) for SHPT use the criteria of parathyroid hormone level (PTH) >800 pg/ml with hypercalcemia and/or hyperphosphatemia, which may be accompanied by symptoms such as bone pain and pruritis that can improve after surgery. Although the reported utility of the various imaging modalities (i.e., 99m-technetium-sestamibi scintigraphy with computed tomography [SPECT/CT], CT, or ultrasound) is highly variable in SHPT, SPECT/CT appears to be the most sensitive. Intraoperatively, PTH monitoring is effective in predicting long-term cure of SHPT but not in predicting hypoparathyroidism. Ectopic and supernumerary parathyroid glands are common in these patients and are often implicated in persistent or recurrent disease. Postoperatively, patients are at risk of severe hypocalcemia and hungry bone syndrome requiring close monitoring and replenishment.

Severe hypercalcemia caused by parathyroid hormone in a rectal cancer metastasis: a case report

BACKGROUND

Hypercalcemia of malignancy is relatively common in several cancers. However, in colorectal cancer, paraneoplastic phenomena that cause hypercalcemia is uncommon. In the few cases that are reported, secretion of parathyroid hormone-related peptide mediates the effect. We describe the first case of severe hypercalcemia mediated by intact parathyroid hormone secretion from a bone metastasis of colorectal origin. This was a diagnostic and therapeutic challenge.

CASE PRESENTATION

A 68-year-old male treated for rectal adenocarcinoma 10 years earlier developed a bone metastasis. After initial treatment of the metastasis with surgery and irradiation, he developed a relapse with severe hypercalcemia and corresponding elevated parathyroid hormone levels. The workup showed no signs of parathyroid adenomas, but the metastasis produced intact parathyroid hormone. The hypercalcemia was successfully treated by irradiation and osteoclast inhibitor, and the patient received chemotherapy. Survival was 24 months from the onset of hypercalcemia.

CONCLUSIONS

Proper diagnosis of the uncommon endocrine disturbance allowed targeted therapy and avoidance of neck exploration for wrongly suspecting primary hyperparathyroidism. Intact parathyroid hormone should be measured in cases of malignant hypercalcemia.

Parathyroid autotransplantation in thyroid surgery

BACKGROUND

Careful parathyroid gland dissection and in situ preservation was the time-honored approach to prevent parathyroid failure after total thyroidectomy. The relative success of parathyroid autotransplantation of hyperplastic parathyroid tissue in patients with renal or hereditary hyperparathyroidism did popularize the use of normal parathyroid tissue autografts during thyroidectomy to prevent permanent hypoparathyroidism. Proof of autograft function in this setting, however, is controversial.

PURPOSE

This narrative review aims at reviewing critically the current status of parathyroid autotransplantation during total thyroidectomy. It is also meant to analyze from the historical, methodological, and clinical points of view the claimed benefit of normal parathyroid gland autotransplantation. A focus is placed on the prevention of permanent hypoparathyroidism by parathyroid autotransplantation.

CONCLUSIONS

Liberal parathyroid autotransplantation was proposed in the mid 1970s but evidence of function is scarce. Proofs are accumulating that parathyroid autografts not only increase the rate of postoperative hypocalcemia, but may be also contribute to permanent hypoparathyroidism.

PTH monitoring after total parathyroidectomy with forearm auto-transplantation: potential for spuriously high levels from grafted forearm

Background

We have identified a cause of falsely elevated parathyroid hormone (PTH) levels after total parathyroidectomy with forearm auto-transplantation (TPT-ATx). Our cases highlight the need to draw PTH samples remotely, away from forearm graft sites, to ensure accurate levels.

Case presentations

We report on four patients who were referred to our surgical team at an academic tertiary care center for what was perceived to be recurrent hyperparathyroidism 2–5 years following total parathyroidectomy with auto-transplantation. Further evaluation revealed highly discrepant results in these patients depending on where the blood was drawn, with spuriously high levels in blood drawn from the grafted arm (Range 337–3885 ng/l), and much lower levels when blood was drawn remotely away from the graft site (Range 9–242 ng/l). The difference in PTH level between the grafted forearm and remote site for these patients ranged between 328 and 3643 ng/l.

Over the period these cases were accrued (2008–2012), 89 patients underwent TPT-ATx in our institution. Therefore, our case report series suggests that this phenomenon will be evident to a clinically important extent in at least 4% of patients.

Conclusions

One can acquire spuriously high PTH levels from grafted forearms, leading to the false diagnosis of recurrent hyperparathyroidism. We recommend PTH levels be drawn remotely from graft sites to ensure accurate systemic levels are reflected.

Medical and Surgical Treatment for Secondary and Tertiary Hyperparathyroidism

Prevention and treatment of secondary hyperparathyroidism (SHPT) in patients on chronic maintenance hemodialysis and of tertiary hyperparathyroidism (THPT) in patients after kidney transplantation is a challenge for the nephrologist and for the surgeon. Indication and results of medical and surgical therapy for SHPT and THPT have remained under discussion during the last decades. This review resumes the current medical and surgical strategies for patients with SHPT and THPT.

Long-Term Surveillance of Treated Hyperparathyroidism for Multiple Endocrine Neoplasia Type 1: Recurrence or Hypoparathyroidism?

BACKGROUND

Primary hyperparathyroidism (HPT) in multiple endocrine neoplasia type 1 (MEN1) is surgically treated with either a subtotal parathyroidectomy removing 3 or 3,5 glands (SPX), less than 3 glands (LSPX), or a total parathyroidectomy with autotransplantation (TPX). Previous studies with shorter follow-up have shown that LSPX and SPX are associated with recurrent HPT, and TPX with hypocalcemia and substitution therapy. We examined the situation after long-term follow-up (median 20,6 years).

METHODS

Sixty-nine patients with MEN1 HPT underwent 110 operations, the first operation being 31 LSPX, 30 SPX, and 8 TPX. Thirty patients underwent reoperative surgery in median 120 months later, as completion to TPX (n = 12), completion of LSPX to SPX (n = 9), extirpation of single glands (n = 3) still resulting in LSPX, and resection of forearm grafts (n = 3). Nine patients underwent a second, and 2 a third reoperation. In 24 patients genetic testing confirmed MEN1, and in the remaining heredity and phenotype led to the diagnosis.

RESULTS

TPX had higher risk for hypoparathyroidism necessitating substitution therapy, at latest follow-up 50%, compared to SPX (16% after 3-6 months; none at latest follow-up). Recurrent HPT was common after LSPX, leading to 24 reoperations in 17 patients. No need for substitution therapy after SPX indicated forthcoming recurrent disease. Not having hypocalcemia in the postoperative period and less radical surgery than TPX were significantly associated to risk for recurrence. Further, mutation in exon 3 in the MEN1 gene may eventually be linked to risk of recurrence.

CONCLUSION

LSPX is highly associated with recurrence and TPX with continuous hypoparathyroidism, also after long-term follow-up. SPX should be the chosen method in the majority of patients with MEN1 HPT.

Autotransplantation of parathyroid grafts into the tibialis anterior muscle after parathyroidectomy: a novel autotransplantation site

Background

Surgical management of renal secondary hyperparathyroidism (sHPT) is varying. Total parathyroidectomy with heterotopic autotransplantation (TPTX + AT) is one of the standard surgical procedures in sHPT, but there is no consensus about the optimal site for graft insertion. At the surgical department of the University Hospital of Heidelberg we prefer the autotransplantation into the tibialis anterior muscle. The aim of this study was to assess the long-term function of the auto-transplanted parathyroid tissue in this type of surgical procedure.

Methods

The function of the autograft of 42 patients was assessed 8.2 ± 2.5 years after surgery, using a modified Casanova-test of the leg bearing the parathyroid tissue. Ischemic blockage was induced by tourniquet and the levels of parathyroid hormone (PTH) were assessed during the test.

Results

At the point of assessment, the ischemic blockage led to a significant reduction in the concentration of PTH (≥50 % of the baseline value) in 19 patients (45 %) indicating well-functioning autografts. In 11 patients (26 %), ischemic blockage did not cause any change in the concentration of PTH (≤20 % of the baseline value), indicating functioning residual parathyroid tissue from another site. The source of PTH production was classified as unidentifiable in five patients (12 %). Two patients had developed graft-dependent recurrent HPT (5 %) without therapeutic consequences and three patients suffered from persistent symptomatic hypoparathyroidism (7 %).

Conclusions

These results indicate that TPTX + AT into the tibialis anterior muscle is a successful surgical treatment for renal HPT and that the modified Casanova-test is a suitable diagnostic tool for autografts function.

Surgical management of secondary hyperparathyroidism in chronic kidney disease--a consensus report of the European Society of Endocrine Surgeons

BACKGROUND

Despite advances in the medical management of secondary hyperparathyroidism due to chronic renal failure and dialysis (renal hyperparathyroidism), parathyroid surgery remains an important treatment option in the spectrum of the disease. Patients with severe and complicated renal hyperparathyroidism (HPT), refractory or intolerant to medical therapy and patients with specific requirements in prospect of or excluded from renal transplantation may require parathyroidectomy for renal hyperparathyroidism.

METHODS

Present standard and actual controversial issues regarding surgical treatment of patients with hyperparathyroidism due to chronic renal failure were identified, and pertinent literature was searched and reviewed. Whenever applicable, evaluation of the level of evidence concerning diagnosis and management of renal hyperparathyroidism according to standard criteria and recommendation grading were employed. Results were discussed at the 6th Workshop of the European Society of Endocrine Surgeons entitled Hyperparathyroidism due to multiple gland disease: An evidence-based perspective.

RESULTS

Presently, literature reveals scant data, especially, no prospective randomized studies to provide sufficient levels of evidence to substantiate recommendations for surgery in renal hyperparathyroidism. Appropriate surgical management of renal hyperparathyroidism involves standard bilateral exploration with bilateral cervical thymectomy and a spectrum of four standardized types of parathyroid resection that reveal comparable outcome results with regard to levels of evidence and recommendation. Specific patient requirements may favour one over the other procedure according to individualized demands.

CONCLUSIONS

Surgery for patients with renal hyperparathyroidism in the era of calcimimetics continues to play an important role in selected patients and achieves efficient control of hyperparathyroidism. The overall success rate and long-term control of renal hyperparathyroidism and optimal handling of postoperative metabolic effects also depend on the timely indication, individually suitable type of parathyroid resection and specialized endocrine surgery.

Sleeping parathyroid tumor: rapid hyperfunction after removal of the dominant tumor

CONTEXT

Due to frequent multiplicity of tumors in multiple endocrine neoplasia type 1, it may be difficult to decide when to stop a parathyroid exploration. A fall of intraoperative serum PTH by a certain percentage during parathyroid surgery is often used as one criterion for ending the operation.

RESULTS

We report two patients with primary hyperparathyroidism due to multiple endocrine neoplasia type 1 who had their first parathyroidectomy at the National Institutes of Health. In both cases, two and a half glands were removed, an extensive search was done for an occult parathyroid tumor, and intraoperative PTH decreased markedly to the lower limits of normal, suggesting a successful operation. Despite this, both patients became hypercalcemic within 3 d after the operation and showed persistent primary hyperparathyroidism. Detailed findings suggest the following course: chronic hypercalcemia had caused near total suppression of PTH secretion by an undiscovered parathyroid tumor (sleeping parathyroid tumor). When the hypercalcemia decreased after surgery due to the removal of the dominant parathyroid tumor(s), the abnormal yet previously suppressed tumor rapidly began to oversecrete PTH and thus caused postoperative hypercalcemia.

CONCLUSIONS

Even a fall of the intraoperative PTH to the lower limits of the normal range cannot guarantee that removal of all parathyroid tumors has been complete in cases with multiple tumors. These findings likely reflect strikingly differing PTH secretory functions among distinct tumors in the same patient, with hypercalcemia at least from a dominant tumor suppressing PTH secretion by one or more other parathyroid tumors.

[Increased bone mineral density in patients with tertiary hyperparathyroidism after total parathyroidectomy and autotransplantation of the parathyroid gland]

INTRODUCTION

Changes in bone metabolism and bone mineral density are observed in renal transplant patients with tertiary hyperparathyroidism. The objective of this work was to analyse the increase in bone mineral density, as well the laboratory results, after total parathyroidectomy and autotransplantation in renal transplant patients with tertiary hyperparathyroidism.

MATERIAL AND METHODS

A retrospective study was conducted in which the bone mineral density values at femoral and lumbar level were analysed, together with the serum levels of calcium, phosphorous, parathyroid hormone (PTH), and alkaline phosphatase in 13 renal transplant patients with tertiary hyperparathyroidism before and after total parathyroidectomy and autotransplantation of the parathyroid glands.

RESULTS

Parathyroidectomy is associated with an increase in bone mineral density at femoral and lumbar level, with an increase of 8.6 ± 6.7% at lumbar level, and 4 ± 16.1% at femoral level. The decrease in calcium after the parathyroidectomy was 2.8 mg/dL (95% CI; 1.9-4). The decrease in PTH was 172 pg/mL (95% CI; 98-354) and the decrease in alkaline phosphatase was 229 U/L (95% CI; 70-371).

CONCLUSIONS

Total parathyroidectomy and autotransplantation of the parathyroid glands in renal transplant patients with tertiary hyperparathyroidism increases the bone mineral density. Furthermore, the calcium, PTH and alkaline phosphatase returned to normal in the long-term.

Recurrence of secondary hyperparathyroidism in patients after total parathyroidectomy with autotransplantation: technical and therapeutic aspects

Recurrence of secondary hyperparathyroidism (rSHPT) in patients after total parathyroidectomy (TPTX) with autotransplantation (AT) represents a major diagnostic and therapeutic challenge. The aim of this retrospective cohort study was to evaluate rSHPT in patients after TPTX with AT and the subsequent surgical treatment. 112 patients with secondary hyperparathyroidism (surgery 1998-2008) were evaluated. In 16 patients, rSHPT was detected, while all of them had been originally operated with TPTX, cervical thymectomy and AT. The recurrence rate of TPTX with AT in our patient cohort was 14.2% (16/112). All the 16 patients with rSHPT suffered from forearm-autotransplant(s) hyperparathyroidism (AT-HPT). AT-HPT was diagnosed after a median of 5.6 years (1.5-11 years). All "forearm" AT-HPT operations were performed using the method of intra-operative parathyroid-hormone measurement. The histopathologic result showed hyperplasia or an adenoma of the reimplanted parathyroid gland (PTG) particles. The parathyroid hormone measurement (PTH) showed normal values in all cases 2 weeks after surgery. In none of the patients persistent hypocalcemia was observed. Our data demonstrates that the high rate of rSHPT in patients after TPTX with AT with renal-insufficiency represents an unsolved problem, often leading to re-operation including possible morbidity. Although we are not showing direct data, we propose, that the alternative method of TPTX without AT, simultaneous cryopreservation and potential metachronous reimplantation could offer an excellent alternative. However, this therapy option needs to be validated in further clinical trials.

Causes and treatment of recurrent hyperparathyroidism after subtotal parathyroidectomy in the presence of multiple endocrine neoplasia 1

BACKGROUND

Subtotal parathyroidectomy (SPTX) is the treatment of choice for hyperparathyroidism in a patient with multiple endocrine neoplasia type 1 (HPT-MEN-1). There are scarce data on the causes, timing, and appropriate surgical treatment of patients with recurrent HPT-MEN-1. The aim of this study was to investigate the timing, causes, site of recurrence, and surgical treatment of recurrent HPT-MEN-1 in patients who underwent SPTX.

METHODS

The study was a retrospective review of prospectively collected data on patients with HPT-MEN-1 with SPTX at two referral institutions. The data collected included the following: demographics, duration of follow-up, weight of resected parathyroid tissue, type of remnant, time to reoperation, cause/site of recurrence, and surgical treatment. We studied prognostic factors of recurrence.

RESULTS

A total of 69 patients underwent SPTX and were followed for a mean of 75.3 months. After the surgery, 15 patients were left with a single "normal" gland and 54 with a 50- to 70-mg remnant of a partially excised abnormal gland. Nine patients (13%) had a recurrence within a mean of 85 months (12-144 months). Patients with a recurrence had been followed longer (115 vs. 66 months; p = 0.005). Five recurrences occurred in a parathyroid remnant, 3 in a previously "normal" gland; the fifth recurrence was in both a hyperplastic remnant and a fifth gland. Remedial surgery included five subtotal resections and four immediate parathyroid autotransplantations. Two patients had a second recurrence due to a supernumerary gland. Factors related with recurrence are the follow-up time (p < 0.01) and thymectomy (p < 0.003).

CONCLUSIONS

Recurrence of HPTP-MEN-1 usually is located in preserved parathyroid tissue with no preference for a previously normal gland or a remnant. A second recurrence is most likely seen in a supernumerary gland. Recurrence is associated with the follow-up time and thymectomy.

Gamma probe radioguided parathyroid forearm surgery in recurrent hyperparathyroidism

A case is described of a successful radioguided forearm graft parathyroidectomy. This is the first report of both pre-operative diagnostic and successful intra-operative localisation during a single procedure, of autologous transplanted parathyroid tissue.

Parathyroidectomy in secondary hyperparathyroidism: Is there an optimal operative management?

BACKGROUND

Subtotal parathyroidectomy (SPTX) and total PTX with autotransplantation (TPTX + AT) are both accepted operations for secondary hyperparathyroidism (2HPT). Studies have shown the 2 procedures to have similar rates of recurrent or persistent HPT (0% to 10%). The majority of these reports are small case series and despite apparently similar outcomes; the optimal operative management for 2HPT remains controversial. The purpose of this study was to determine whether there were any clinical outcome differences between these apparently comparable operations.

METHODS

A meta-analysis of 53 publications on reoperative operation for 2HPT from 1983 to 2004 identified 501 patients who had undergone an operation for recurrent or persistent 2HPT. The data evaluated included the type of initial operation, the need for reoperative operation as it related to the type of initial operation, and the intraoperative findings.

RESULTS

The initial operation had been a SPTX in 36% and a TPTX + AT in 64% of patients. Reoperative operation was for persistent 2HPT in 82 of 485 (17%) and for recurrent 2HPT in 403 of 485 (83%) patients. Findings at reoperation included: autograft hyperplasia (49%), supernumerary glands (20%), remnant hyperplasia (17%), a missed in situ gland (7%), and a negative exploration (5%). Supernumerary glands, missed in situ glands, and negative explorations occurred at equal rates for both operations. Reoperation determined that inadequate cervical explorations occurred in 42% of patients who had undergone a SPTX and in 34% of patients who had undergone a TPTX + AT.

CONCLUSIONS

Operative failures occur because of the limitations in preoperative localization, inadequate exploration, and the natural history of hyperplastic parathyroid tissue. The initial operation should include an attempt to localize supernumerary glands both pre- and intra-operatively.

Definitive treatment for persistent hypoparathyroidism in a kidney transplant patient: parathyroid allotransplantation

Post-surgical hypocalcemia is usually a transitory complication in thyroid and parathyroid surgery that can be resolved quickly, although it becomes a delicate matter when the problem persists. Parathyroid transplantation is the choice of treatment; however, the associated immunosuppression can cause side effects. The following case study shows the transplantation of parathyroid tissue from a patient with secondary hyperparathyroidism to another kidney transplant patient with severe hypocalcemia that was medically intractable. The graft is functioning after 2 years.

[Multiple endocrine neoplasia type 1. Surgical therapy of primary hyperparathyroidism]

Primary hyperparathyroidism (pHPT) occurs in about 90% of patients with multiple endocrine neoplasia type 1 (MEN1). In contrast to sporadic pHPT, multiple gland disease is most common in MEN1. The appropriate surgical approach is still controversial. The aim of this study was to analyze the results of surgical therapy of pHPT in patients with genetically confirmed MEN1. In an observational study, preoperative data, operative procedures, long-term results, and a possible genotype-phenotype correlation were analyzed in patients with pHPT and genetically confirmed MEN1. According to our results, tPTX+T (total parathyroidectomy+thymectomy+autotransplantation) seems to be a more favorable surgical approach in patients with MEN1 pHPT than sDE (selective gland exstirpation) and stPTX (subtotal parathyroidectromy) without cervical thymectomy, because recurrences or persistence of the disease are rare. A prospective randomized trial is needed to compare stPTX including cervical thymectomy vs tPTX+T. A genotype-phenotype correlation could not be identified.

Parathyroid surgery in familial hyperparathyroid disorders

The management of hyperparathyroidism (HPT) in the setting of familial HPT differs between the specific syndromes and is generally complex because of the underlying disease, which predisposes patients to persistent and recurrent HPT. The basic principles of surgery include achieving and maintaining normocalcaemia for the longest time possible, avoiding both iatrogenic hypocalcaemia and operative complications, and facilitating future surgery for recurrent disease. Multiple endocrine neoplasia type 1 (MEN1) is treated with either subtotal parathyroidectomy or total parathyroidectomy with immediate heterotopic autotransplantation of parathyroid tissue. MEN2A, familial isolated HPT and HPT-associated with the hyperparathyroidism-jaw tumour (HPT-JT) syndrome typically can be treated with parathyroidectomy, i.e. subtotal or less. The increased risk of parathyroid cancer in HPT-JT requires special attention. Parathyroid surgery in familial HPT syndromes in the setting of underlying mutations in the calcium receptor (CASR) gene involves radical subtotal parathyroidectomy. Intraoperative parathyroid hormone (PTH) measurements may help guide the extent of parathyroid resection, particularly in the case of multigland HPT. The vast majority of patients with familial HPT who require surgery are best served with bilateral cervical explorations. However, minimally invasive parathyroidectomy (MIP) techniques that have become routine for sporadic HPT at selected institutions may be extrapolated to a subset of cases of familial HPT.

[Surgery of hyperparathyroidism and of its potential recurrence in the MEN I setting]

Hyperparathyroidism (HPT) in the setting of multiple endocrine neoplasia type 1 (MEN I) is almost constant and occurs often early in the course of the disease. Underlying pathology is almost always multiglandular because of its genetic origin, and therefore, in case of less than subtotal parathyroidectomy, recurrence rate amounts to 20-40%. Operative strategy aims to find and check all parathyroid glands including possible supernumerary one(s) found in 30% of patients and to perform a subtotal parathyroidectomy. Combined transcervical thymectomy is a mandatory part of the procedure. Moreover HPT triggers the secretion of associated gastrinomas and its cure can thus delay the timing of duodenopancreatic surgery. In case of recurrent HPT, preoperative work-up yields to image the parathyroid remnant and possible supernumerary gland(s). Reoperation aims to remove all parathyroid tissue. Cryopreservation can be useful in case of permanent long-lasting symptomatic hypoparathyroidism.

Relapsing Secondary Hyperparathyroidism Due to Multiple Nodular Formations after Total Parathyroidectomy with Autograft

Total parathyroidectomy with autograft represents an optimal surgical technique in the treatment of secondary hyperparathyroidism. Relapsing hyperparathyroidism due to miliary-type nodular formations scattered over the autograft site represents a complication that is rarely described in the literature. We examined five case histories of patients relapsing as a result of miliary-type nodular formations in the autograft site; in four cases the relapse was localized in the upper limb and in one case in a pouch of the sternocleidomastoid muscle. The patients underwent removal of the hyperfunctioning parathyroid formations accompanied by demolition of the surrounding muscle tissue. The relapsing hyperparathyroidism caused by multiple miliary-type nodular formations is a rare occurrence, akin to parathyromatosis. The increasingly widespread use of total parathyroidectomy with autograft to treat secondary hyperparathyroidism can lead to an increase in the incidence of this complication. Correct surgical technique and a careful selection of the parathyroid tissue to be autografted can prevent this complication. Furthermore, extensive demolition of the muscle tissue in the autograft site can prevent further relapses. Intraoperative rapid parathormone assay was found to be predictive of the disease's persistence and recurrence.

Double-phase parathyroid 99mTc-Sestamibi scintigraphy in chronic haemodialysis patients: correlation with biochemical markers of parathyroid function

99mTc-Sestamibi identifies the presence of hyperfunctioning autonomous parathyroid glands in patients with secondary hyperparathyroidism (SHP). The objectives of this study were: (i) to evaluate the interdependence between biochemical markers of SHP and 99mTc-Sestamibi uptake; and (ii) to determine whether 99mTc-Sestamibi uptake could be efficiently predicted by any combination of the former variables. Double-phase parathyroid 99mTc-Sestamibi uptake and total serum calcium, phosphorus, intact parathormone, 25-OH vitamin D and 1,25(OH) vitamin D determinations were performed simultaneously in 74 patients (36 female, 38 male) with SHP. Planar images of the neck and upper thorax were obtained in anterior view, 15 min (early phase) and 120 min (delayed phase) after the injection of 740 MBq of 99mTc-Sestamibi. In each patient, a final parathyroid/thyroid (P/T) activity index was obtained by adding the results of the P/T index of all parathyroid lesions. There was a significant correlation between intact parathormone levels and delayed 99mTc-Sestamibi uptake ( r=0.656; P<0.01). Of all the variables, intact parathormone was the only significant predictor of delayed 99Tc-Sestamibi uptake ( r=0.487; P<0.001). Calcium, phosphorus, vitamin D metabolites, age, gender, time spent on haemodialysis and cause of chronic renal failure displayed no significant correlation with 99mTc-Sestamibi uptake. It can be concluded that 99mTc-Sestamibi uptake is a potential predictor of parathyroid function in SHP patients. Hence, 99mTc-Sestamibi scintigraphy could be useful to assess parathyroid function and in the clinical follow-up of these patients.

Reoperation for secondary uremic hyperparathyroidism: are technical difficulties influenced by initial surgical procedure?

BACKGROUND

Parathyroid surgery in patients with uremia and secondary hyperparathyroidism is performed either by subtotal parathyroidectomy or total parathyroidectomy with immediate reimplantation. The aim of this study was to compare the results of reoperation for persistent or recurrent hyperparathyroidism after parathyroidectomy according to which initial operative procedure was used.

PATIENTS AND METHODS

Eighty-nine patients had reoperation for persistent (28 patients) or recurrent (61 patients) hyperparathyroidism after 53 subtotal parathyroidectomies and 36 total parathyroidectomies with immediate reimplantation. Results of the reoperation were assessed in terms of success rate, morbidity, and operative findings.

RESULTS

The success rate of reoperation in patients with persistent hyperparathyroidism was 89% and was independent of the initial type of surgery. Success rates of reoperation for recurrent hyperparathyroidism after initial subtotal parathyroidectomy and total parathyroidectomy with immediate reimplantation were 87% and 70%, respectively (P = .02). Hypertrophy of the parathyroid remnant was the main cause of recurrence after subtotal parathyroidectomy. After total parathyroidectomy with immediate reimplantation, recurrence was located in the graft in half the patients, while hyperplastic tissue was found in the neck or the mediastinum in the other half.

CONCLUSIONS

Subtotal parathyroidectomy provides the best conditions for successful reoperation in case of recurrent hyperparathyroidism and should become the surgical treatment of choice for secondary hyperparathyroidism.

Subcutaneous forearm transplantation of autologous parathyroid tissue in patients with renal hyperparathyroidism

BACKGROUND

Parathyroidectomy is required in up to 5% of patients with chronic renal failure. Intramuscular transplantation of autologous parathyroid tissue in the forearm has been the traditional method of transplantation at the time of total parathyroidectomy. The removal of an intramuscular transplantation can be technically difficult should graft-dependent hyperparathyroidism (GRH) occur. This problem resulted in our initiating a study of subcutaneous transplantation with total parathyroidectomy in patients with renal failure.

METHODS

Twenty-six patients who were receiving dialysis therapy underwent total parathyroidectomy and subcutaneous transplantation. Parathyroid tissue was diced into 1- to 2-mm pieces, and 6 pieces were grafted into 6 subcutaneous pockets of the forearm. Intact parathyroid hormone was measured within 48 hours of operation and in the bilateral antecubital veins 1 to 24 months after the operation to assess completeness of resection and graft function, respectively.

RESULTS

No major surgical complications occurred. Symptoms improved in 24 patients (85%). Graft failure rate was 4.3%. No GRH was observed. Follow-up was 4 to 55 months (mean, 27 months).

CONCLUSIONS

This study indicates that the subcutaneous transplantation function is comparable to intramuscular transplantation and suggests a decreased incidence of GRH. Subcutaneous transplantation is technically easier than intramuscular transplantation and has the additional advantage of easy removal should GRH occur.

Five to 10 years follow-up after total parathyroidectomy and autotransplantation of parathyroid tissue: evaluation of parathyroid function by use of ischaemic blockade manoeuvre

The aim of the present study was to assess the long-term function of autotransplanted parathyroid tissue in patients with chronic renal disease. We examined the medical records of a consecutive series of 21 patients with chronic renal failure, who had undergone total parathyroidectomy with autotransplantation. During the time of follow-up, on average 79 months, one patient developed graft-dependent recurrent hyperparathyroidism and one patient suffered from persistent hypoparathyroidism. Nine of the patients were available for a clinical study. In these patients we measured the plasma concentration of intact PTH in blood from the arm contralateral to the graft-bearing arm at rest and during a short-lasting ischaemic blockade of the graft site from the circulating blood. At rest all nine patients had parathyroid hormone (PTH) values within the normal range. The ischaemic blockade produced a marked reduction in the plasma concentration of intact PTH in eight of the patients indicating well functioning autografts. Prior to the examination the patient with recurrent hyperparathyroidism had undergone resection of the autograft. In this patient, ischaemia of the former graft site did not cause any change in the concentration of PTH indicating normally functioning residual parathyroid tissue in the neck. Thus, the ischaemic blockade manoeuvre seems suitable for the assessment of autografted parathyroid tissue. Our results indicate that total parathyroidectomy with autotransplantation provides a rational alternative to the surgical treatment of secondary hyperparathyroidism.

Primary hyperparathyroidism: problems in management

Most hyperparathyroidism is subclinical, with no complaints of bone pain, constipation, mental confusion, or depression, no skeletal findings on x-ray, and no history of kidney stones. Routine hyperparathyroidectomy for asymptomatic hypercalcemia, with normal bone density and normal calciuria, particularly with moderate elevations of serum calcium, is now generally rejected.