Experienced radio-guided surgery teams can successfully perform minimally invasive radio-guided parathyroidectomy without intraoperative parathyroid hormone assays

Minimally invasive parathyroidectomy is an accepted treatment option for primary hyperparathyroidism. The need for intraoperative parathyroid hormone assays (iPTH) to confirm adenoma removal remains controversial. We studied minimally invasive radio-guided parathyroidectomy (MIRP) performed using preoperative sestamibi localization studies, intraoperative gamma detection probe, and the selective use of frozen section pathology without the use of iPTH. This is a single institution review of patients with primary hyperparathyroidism treated with MIRP by surgeons experienced in radio-guided surgery between October 1, 1998 and July 15, 2005. Information was obtained by reviewing computer medical records as well as contacting primary care physicians. Factors evaluated included laboratory values, pathology results, and evidence of recurrence. One hundred forty patients were included with a median preoperative calcium level of 11.3 mg/dL (range, 9.6-17) and a PTH level of 147 pg/mL (range, 19-5042). The median postoperative calcium level was 9.3 mg/dL. All patients were initially eucalcemic postoperatively except for one who had normal parathyroid levels. However, five (4%) patients required re-exploration for various reasons. Of the failures, one was secondary to the development of secondary hyperparathyroidism, and therefore would not have benefited from iPTH, one had thyroid tissue removed at the first operation, and three developed evidence of a second adenoma. One of these three patients had a drop in PTH level from 1558 pg/mL preoperatively to 64 pg/mL on postoperative Day 1, indicating that iPTH would not have prevented this failure. Thus, only three (2.1%) patients could have potentially benefited from the use of iPTH. MIRP was successful in 96 per cent of patients using a combination of preoperative sestamibi scans, intraoperative localization with a gamma probe, and the selective use of frozen pathology. This correlates with reported success rates of 95 per cent to 100 per cent using iPTH. We conclude that minimally invasive parathyroidectomy can be successfully performed without using iPTH assays.     

Video-assisted parathyroidectomy in the management of patients with primary hyperparathyroidism

INTRODUCTION: In recent years, different minimally invasive techniques of parathyroidectomy have been described. We performed a retrospective study to evaluate the indications and results of video-assisted parathyroidectomy (Vap) in the management of our patients with primary hyperparathyroidism (PHPT). MATERIALS AND METHODS: During the last 5 years (1998-2002), we operated on 528 patients with PHPT. Vap was proposed for patients with sporadic PHPT, without associated goiter and without previous neck surgery, in whom a single adenoma was localized by means of sonography and/or sestamibi scanning. Vap was performed by lateral approach with insufflation for patients with adenoma located deeply in the neck and by gasless midline approach for patients with adenoma located anteriorly. A quick parathyroid (qPTH) assay was used during the surgical procedures. Calcemia, phosphoremia and PTH were systematically evaluated in patients on days 1 and 8, 1 month and 1 year after surgery. All patients underwent pre-operative and postoperative investigations of vocal cord movements. RESULTS: Among 528 patients with PHPT, 228 (43%) were not eligible for Vap: associated nodular goiter (99 cases), previous neck surgery (42 cases), suspicion of multiglandular disease (25 cases), lack of pre-operative localization (48 cases), and miscellaneous causes (14 cases). Vap was performed in 300 patients with sporadic PHPT: 282 lateral access, 17 midline access and 1 thoracoscopy. Median operative time was 50 min (20-130 min). Conversion to conventional parathyroidectomy was required in 42 patients (14%): missed adenomas (11 cases), difficulties of dissection (7 cases), multiglandular disease correctly predicted by qPTH (10 cases); qPTH assay false negative results (3 cases), sestamibi scan false positive results (10 cases) and 1 sonography false positive result. One patient presented definitive recurrent nerve palsy. One patient had a persistent PHPT and one other patient had a recurrent PHPT. CONCLUSION: Vap can be proposed for more than half of patients with PHPT. In our experience Vap and conventional parathyroidectomy are complementary. Immediate results of Vap are similar to those obtained with conventional parathyroidectomy but no conclusions can be drawn in terms of influence of Vap on the outcome of the patients operated for PHPT.     

Chasing ��Shadows��: Discovering the Subtleties of Sestamibi Scans to Facilitate Minimally Invasive Parathyroidectomy

Background  

With the advent of sestamibi scans, high-resolution ultrasonography (US), and intraoperative intact parathyroid hormone (PTH) measurements, minimally invasive parathyroidectomy (MIP) is considered the standard of care for patients with primary hyperparathyroidism (PHPT). Preoperative imaging, however, can be negative more than 20% of the time.     

Procedimiento radioguiado en la cirugía mínimamente invasiva del hiperparatiroidismo primario

Minimally invasive parathyroidectomy, of choice in most cases of primary hyperparathyroidism, shows a high detection rate, based on precise preoperative localization by MIBI scintigraphy (SPECT/CT) and neck ultrasound. Radio-guided minimally invasive parathyroidectomy is an even more effective technique, which shortens surgical times, maintains minimal incision and few complications, allows immediate verification of parathyroid adenoma removal and is especially interesting in patients with ectopic lesions or cervical surgical history. In this paper, the indications, protocols and differences between the two available radio-guided parathyroid surgery procedures (MIBI and ROLL) are exposed.     

Sestamibi Scan–directed Parathyroid Surgery: Potentially High Failure Rate without Measurement of Intraoperative Parathyroid Hormone

The present study evaluated sestamibi scan–directed parathyroidectomy with intraoperative parathyroid hormone (PTH) assessment (ioPTH). The preoperative sestamibi scintigraphies were compared with the intraoperative findings for 103 patients undergoing first exploration for sporadic primary hyperparathyroidism (pHPT). Data were collected prospectively. Ninety-nine patients (96%) were cured. Patients with persistent pHPT (n = 4) all had an incorrect scintigram as well as an insufficient decline of ioPTH. At operation, 90 patients (87%) had solitary parathyroid adenoma; 12 patients had multiglandular disease. In one patient no enlarged parathyroid gland was found. Overall 77 of 118 abnormal glands (65%) were correctly identified by sestamibi scintigraphy. The sensitivity for localizing a single parathyroid adenoma was 80%. Patients with incorrect scintigrams had a higher proportion of upper pole adenomas than patients with correct scans. High glandular weight and high level of serum PTH were important factors for detectability. Sestamibi scintigraphy did not predict multiglandular disease. However, the use of ioPTH identified 8 of the 9 patients with a positive scan (a solitary focus) and multiglandular disease. In contrast, false-negative ioPTH led to four unnecessary bilateral explorations in the 63 patients with a scan-identified adenoma. With the help of ioPTH, a focused parathyroidectomy was accomplished in 43% of scan-negative patients with a solitary adenoma. In conclusion, sestamibi scintigraphy is an acceptable method for localizing a solitary parathyroid adenoma. However, the technique alone does not reliably predict multiglandular disease. Potentially the failure rate in scan-directed parathyroidectomy could increase, with up to 10% of patients without ioPTH.This article was presented at the International Association of Endocrine Surgeons meeting, Uppsala, Sweden, June 14-17, 2004.     

The Negative Sestamibi Scan: Is a Minimally Invasive Parathyroidectomy Still Possible?

Background Tc-99-sestamibi scanning is utilized to determine whether patients with primary hyperparathyroidism (HPT) are candidates for minimally invasive parathyroidectomy (MIP). However, if the result of this scan is negative, many surgeons recommend bilateral parathyroid exploration because of possible multi-gland disease. The objectives of this study were to determine whether patients with primary HPT and negative sestamibi scans can benefit from additional imaging studies and are still potential candidates for MIP. Methods Between March 2001 and April 2006, 578 consecutive patients with HPT underwent parathyroidectomy by a single surgeon. Pre-operative sestamibi scans had been done in 458 (79%) of these patients, 90 (20%) of which had negative results. These patients formed our study cohort. Results Of the 90 patients, 60 (67%) had a single adenoma, 17 (19%) double adenomas and 13 (14%) 3- to 4-gland hyperplasias. In 74 (82%) patients, localization was further investigated with one or more studies including thallium subtraction scans (n = 30), ultrasound (n = 15) and intra-operative internal jugular venous sampling (n = 49). Additionally, the use of radio-guided techniques intra-operatively facilitated minimally invasive techniques. Of these 90 patients, 47 had positive results from preoperative studies, including 12 positive thallium, 5 positive ultrasound and 13 positive internal jugular sampling results. In addition, positive results were observed for 17 patients using radio-probe techniques in the operating room. Accordingly, minimally invasive techniques were attempted in these 47 patients; 42 (89%) had single adenomas and in 5 the technique was converted to bilateral exploration for double adenoma/hyperplasia. In the setting of a negative sestamibi, the sensitivities of thallium scans and ultrasound were 30% and 27%, respectively. The overall cure rate in the 90 patients with negative sestamibi scans was 99%. Conclusion In patients with primary HPT and a negative sestamibi scan, most patients (67%) will have a single adenoma. These patients benefitted from additional localization tests, which yielded a positive result in 52% of patients. Therefore, even in the setting of a negative sestamibi scan, the majority of patients with primary HPT are still candidates for MIP.     

Surgery for parathyroid microadenomas: patient characteristics,localization success and operative cures

Background

In recent years, patients with primary hyperparathyroidism (PHPT) are being diagnosed earlier, with milder elevations in parathyroid hormone (PTH) and serum calcium. We aimed to investigate whether adenoma size reflects biochemical severity of presentation and influences localization of pre‐operative scans.

Methods

A total of 630 consecutive patients undergoing parathyroidectomy for PHPT were recruited into either the microadenoma (≤200 mg) or macroadenoma (>200 mg) group. Pre‐operative serum calcium, PTH, rates of minimally invasive parathyroidectomy and bilateral neck exploration, localization of adenomas with pre‐operative ultrasound and sestamibi (MIBI) scans, cure rates and other demographic parameters were compared. The data were analysed using Student's t‐test, Chi‐squared test, linear and multiple regression analyses.

Results

Patients in the microadenoma group had significantly lower pre‐operative serum calcium (P < 0.001) and PTH (P < 0.001), less accurate MIBI (P < 0.001) and ultrasound (P < 0.001), lower cure rates (P = 0.04) and were more likely to undergo bilateral neck exploration (P = 0.001). However, multivariate analysis revealed that microadenomas are most strongly associated with the findings of less accurate MIBI (P = 0.03) and lower pre‐operative calcium (P = 0.04).

Conclusion

In conclusion, smaller adenomas are strongly associated with biochemically milder PHPT and less accurate localization studies. Therefore, microadenomas continue to present as a challenge in both diagnosis and management.     

Incremental value and clinical impact of neck sonography for primary hyperparathyroidism: a risk-adjusted analysis

Background

Despite the different preoperative imaging modalities available for parathyroid adenoma localization, there is currently no uniform consensus on the most appropriate preoperative imaging algorithm that should be routinely followed prior to the surgical management of primary hyperparathyroidism (PHPT). We sought to determine the incremental value of adding neck ultrasonography to scintigraphy-based imaging tests.

Methods

In a single institution, surgically naive patients with PHPT underwent the following localization studies before parathyroidectomy: 1) Tc-99m sestamibi imaging with single photon emission computed tomography/computed tomography (SPECT/CT) or Tc-99m sestamibi imaging with SPECT alone, or 2) ultrasonography in addition to those tests. We retrospectively collected data and performed a multivariate analysis comparing group I (single study) to group II (addition of ultrasonography) and risk of bilateral (BNE) compared with unilateral (UNE) neck exploration.

Results

Our study included 208 patients. Group II had 0.45 times the odds of BNE versus UNE compared with group I (unadjusted odds ratio [OR] 0.45, 95% confidence interval [CI] 0.25–0.81, p = 0.008). When adjusting for patient age, sex, preoperative calcium level, use of intraoperative PTH monitoring, preoperative PTH level, adenoma size, and number of abnormal parathyroid glands, Group II had 0.48 times the odds of BNE versus UNE compared with group I (adjusted OR 0.48, 95% CI 0.23–1.03, p = 0.06). In a subgroup analysis, only the addition of ultrasonography to SPECT decreased the risk of undergoing BNE compared with SPECT alone (unadjusted OR 0.40, 95% CI 0.19–0.84, p = 0.015; adjusted OR 0.38, 95% CI 0.15–0.96, p = 0.043).

Conclusion

The addition of ultrasonography to SPECT, but not to SPECT/CT, has incremental value in decreasing the extent of surgery during parathyroidectomy, even after adjusting for multiple confounding factors.     

Intraoperative real-time <Superscript>99m</Superscript>Tc-sestamibi scintigraphy with miniature gamma camera allows minimally invasive parathyroidectomy without ioPTH determination in primary hyperparathyroidism

Background  Minimally invasive parathyroidectomy (MIP) is being widely accepted as the procedure of choice for the treatment of primary hyperparathyroidism (PHPT), which is caused by a parathyroid single adenoma in more than 80% of cases in some series. Preoperative location studies, like sestamibi scans, allow the proper identification of pathologic gland and intraoperative parathormone (ioPTH) assay is used to confirm the removal of the adenoma. We have studied the feasibility of a new miniature gamma camera (MGC) used intraoperatively to locate parathyroid adenomas and confirm its correct excision. Materials and methods  Twenty patients with PHPT positively diagnosed by preoperative sestamibi scans underwent a MIP. In the first five patients, both ioPTH assay and the new hand-held MGC were used consecutively to locate and confirm the excision of the pathologic gland. For the next 15 cases, PTH was measured but not used intraoperatively for diagnosis and the MGC was the only diagnostic tool employed to perform the operation. Concordance between preoperative and intraoperative scintigraphy, surgical time, success rate, and complications are analyzed. Results  All cases were operated on successfully by a MIP. After 1 year follow-up, the drop of PTH and the normalization of calcium levels confirmed the excision of all pathologic tissue. The MGC proved its usefulness in all patients offering accurate real-time intraoperative images for location and confirming the success of the procedure. Conclusions  The MGC is a useful instrument in MIP for PHPT. It may be used as complementary to the standard tools used to date, or even replace them, at least in selected cases of single adenomas. Best of Endocrine Surgery in Europe 2009     

Endoscopic Parathyroid Surgery: Results of 365 Consecutive Procedures

In recent years, several series have documented the feasibility of endoscopic approaches for parathyroid diseases. We performed a retrospective study to evaluate the results of endoscopic parathyroidectomy (EP) in the management of our patients with primary hyperparathyroidism (PHPT). During a 5.5 year period (1998–2003), we operated on 644 patients with PHPT. EP was proposed for patients with sporadic PHPT, without associated goiter, and without previous neck surgery in whom a single adenoma was localized by means of sonography and sestamibi scanning. EP was performed by the lateral approach with insufflation for patients with an adenoma located deep in the neck and by a gasless midline approach for patients whose adenoma was located anteriorly. A quick parathyroid (QPTH) assay was used during the surgical procedures. Among 644 patients with PHPT, 279 (43.3%) were not eligible for EP for the following reasons: associated nodular goiter (116 cases), previous neck surgery (52 cases), suspicion of multiglandular disease (31 cases), lack of preoperative localization (61 cases), and miscellaneous causes (19 cases). EP was performed in 365 patients with sporadic PHPT: 339 lateral access, 25 midline access, and one thoracoscopy. The median operating time was 49 minutes (16–130 minutes). Conversion to conventional parathyroidectomy was required in 49 patients (13.4%) for these reasons: missed adenomas (14 cases), difficulty with the dissection (8 cases), multiglandular disease correctly predicted by QPTH (11 cases), false-negative QPTH assay results (4 cases), false-positive sestamibi scan results (11 cases), and 1 false-positive sonography result. One patient presented with definitive recurrent nerve palsy. Three patients remained hypercalcemic, and one other patient had recurrent hypercalcemia. In conclusion, EP can be proposed for more than half of the patients with PHPT. Immediate results of EP are similar to those obtained with conventional parathyroidectomy, but no conclusions can be drawn in terms of the influence of EP on the outcome of the patients operated on for PHPT.This article was presented at the International Association of Endocrine Surgeons meeting, Uppsala, Sweden, June 14–17, 2004.     

Preoperative technetium Tc 99m sestamibi SPECT imaging in the management of primary hyperparathyroidism in patients with concomitant multinodular goiter

HYPOTHESIS: Preoperative parathyroid and thyroid imaging using technetium Tc 99m sestamibi scintigraphy-single-photon emission computed tomography (Tc 99m MIBI SPECT) and technetium Tc 99m sodium pertechnetate, respectively, in patients with parathyroid adenomas and concomitant multinodular goiters enables the selection of those suitable for minimally invasive radio-guided surgery. DESIGN: One hundred thirty patients with primary hyperparathyroidism were treated surgically during a 30-month period. Forty-one of these 130 patients had an associated multinodular goiter. All patients underwent planar and SPECT parathyroid scintigraphy using Tc 99m MIBI, and thyroid scintigraphy with technetium Tc 99m pertechnetate 2 to 5 days before surgery. On the morning of surgery each patient was reinjected with Tc 99m MIBI for intraoperative localization and validation. Minimally invasive radio-guided parathyroidectomy was performed using a handheld gamma-detection device with a thyroid probe. Removed glands were submitted for histopathologic examination for comparison with the scintigraphic results. Quantitative analysis of parathyroid activity was performed. RESULTS: Minimally invasive, radioguided parathyroidectomy was successfully performed in 21 (51%) of 41 patients who had a concomitant multinodular goiter. The remaining 20 patients underwent standard neck exploratory surgery because of associated thyroid disease; 5 of them had malignant thyroid disease. Among the 41 patients planar scintigraphy correctly identified 28 adenomas (68%). Single-photon emission computed tomographic imaging identified an additional 11 adenomas for a sensitivity of 95% and a specificity of 100%. Moreover, SPECT imaging correctly identified malignant thyroid nodules in 4 of 5 patients. Technetium Tc 99m MIBI retention was noted in only 25 adenomas (61%) while the remaining adenomas demonstrated a rapid washout. The average uptake ratio of parathyroid counts to maximum thyroid activity was significantly correlated with parathyroid hormone levels before surgery (P = .04). CONCLUSIONS: Our data encourage the use of preoperative SPECT imaging of parathyroid adenomas in patients who have multinodular goiters to select those suitable for minimally invasive radioguided surgery. This technique also offers important information regarding thyroid nodules that are suspicious for malignancy. The intraoperative gamma-probe technique enables the surgeon to focus his or her search, provides instant feedback regarding the progress of the operation, reduces surgical trauma and complications, and yields better cosmetic results. Patients with higher presurgical parathyroid hormone levels may especially benefit from radioguided surgery.     

Can a Lightbulb Sestamibi SPECT Accurately Predict Single-Gland Disease in Sporadic Primary Hyperparathyroidism?

Background Technetium-99m sestamibi scintigraphy with single photon emission computed tomography (SPECT) is widely used to guide minimally invasive exploration in patients with sporadic primary hyperparathyroidism (SPH), although its sensitivity in multiglandular disease is limited. We examined the incidence of missed multiglandular disease and associated anatomic findings when sestamibi SPECT was positive for a single intense focus of delayed tracer uptake, termed a lightbulb scan (LBS). Methods Prospectively entered data from 764 patients with SPH treated with initial parathyroid exploration from March 5, 2000, to December 31, 2006, were reviewed. A single radiologist performed blinded interpretation of 585 available sestamibi SPECT images, classifying 167 (28.5%) patients with a LBS. Clinical findings were compared among LBS patients with a single adenoma (true positive) and LBS patients with multiglandular disease (false negative). Results One hundred fifty of 167 (89.8%) LBS patients had a single adenoma and 3 (1.8%) had carcinoma. Multiglandular disease was anatomically present in 14 of 167 (8.4%) LBS patients compared with 60 of 418 (15.6%) non-LBS patients (p = 0.05). Parathyroid hyperplasia occurred less frequently in LBS patients [5/167 (3%)] compared with non-LBS patients [36/418 (8.6%)], (p = 0.02), while double adenomas occurred equally often in LBS patients [9/167 (5.4%)] compared with non-LBS patients [24/418 (5.7%)], (p = 0.87). Double adenomas in LBS patients were more likely ipsilateral (7/9, p = 0.005) and left-sided (7/7, p = 0.008). LBS patients with multiglandular disease were more likely to have a history of neck irradiation, prior neck exploration, and concomitant thyroid pathology. Conclusions In patients with SPH, sestamibi SPECT studies show a single bright focus of uptake in only 29% of patients. LBS findings do not exclude multiglandular disease. To avoid unacceptable rates of failure at initial parathyroid exploration, the expert surgeon should use validated adjuncts such as intraoperative PTH monitoring or four-gland exploration.     

Minimally invasive parathyroidectomy with operative ultrasound localization of the adenoma

Background Minimally invasive parathyroidectomy is the procedure of choice for primary hyperparathyroidism due to parathyroid adenoma. Adequate perioperative adenoma localization is essential for this operation. We describe a technique using ultrasound to perform minimally invasive parathyroidectomy.Methods ^99mTc sestamibi scanning was performed on patients with primary hyperparathyroidism to localize parathyroid adenomas; no intraoperative gamma probe was used. We also performed pre- and intraoperative ultrasound scanning to localize these adenomas.Results All patients underwent successful localization and removal of their parathyroid adenomas. At follow-up, all patients were well, with calcium within normal limits.Conclusion The use of intraoperative ultrasound facilitates minimally invasive parathyroidectomy and may obviate the need for intraoperative ^99mTc sestamibi scanning.     

Indications and results of video-assisted parathyroidectomy by a lateral approach in patients with primary hyperparathyroidism.

BACKGROUND: Different minimally invasive techniques of parathyroidectomy have been described. We performed a retrospective study to evaluate the indications and results of video-assisted parathyroidectomy by lateral approach (VAPLA) in the management of our patients with primary hyperparathyroidism (PHPT). METHODS: From December 1997 to December 2000, we operated on 293 patients with PHPT. VAPLA was proposed for patients with sporadic PHPT in whom a single adenoma was localized by means of sonography or sestamibi scanning, or both. VAPLA was performed on the anterior border of the sternocleidomastoid muscle. A quick parathormone (PTH) assay was used during the surgical procedures. RESULTS: Of the 293 patients, 127 (43.3%) were not eligible for VAPLA: ipsilateral previous neck surgery (28 cases), associated nodular goiter (59 cases), suspicion of multiglandular disease (15 cases), no preoperative localization (17 cases), and miscellaneous causes (8 cases). VAPLA was performed in 166 patients (56.7%). Conversion to conventional parathyroidectomy was required in 26 patients (15.6%). Morbidity included 2 local hematomas, 1 definitive recurrent nerve palsy, and 4 capsular fractures. All of the 166 patients were normocalcemic, with follow-up ranging from 3 to 33 months. CONCLUSIONS: VAPLA is safe and effective. It should be reserved for patients with sporadic PHPT, with a small single adenoma clearly localized preoperatively.     

Minimally invasive video-assisted parathyroidectomy – selective approach to localized single gland adenoma

Background: The valid operative standard for primary hyperparathyroidism (pHPT) consists of cervicotomy and presentation of all parathyroid glands. This operative technique features the macroscopic identification of the responsible adenoma. It also has the advantage of detecting multiglandular disease. The increasing sensitivity of preoperative localization methods and the possibility of intra-operative measurement of parathyroid hormone prepared the way for minimally invasive procedures. Methods: All patients with pHPT were examined by cervical sonography and sestamibi scintigraphy of the parathyroid glands. Patients eligible for the described procedure had to comply to the following inclusion criteria: biochemical evidence of pHPT, localization of one unequivocally enlarged parathyroid gland on two corresponding imaging results; no former surgery or radiation to the neck; no multinodular goiter; no suspected carcinoma of the thyroid; and no secondary or recurrent hyperparathyroidism. We used an operative technique first described by Miccoli in 1997. Before preparation and at 2, 10 and 15 min after exstirpation of the parathyroid adenoma, peripheral blood was drawn. The operation was terminated when a 50% decrease of preoperative PTH levels was reached. Results: During a 12-month period (1 December 1997 to 30 November 1998), 13 patients with pHPT of a total of 59 patients (22%) with hyperparathyroidism (pHPT and sHPT) were operated on employing this minimally invasive procedure. In three patients, the operative technique had to be converted to the conventional procedure due to superior adenomas in two cases and a dorsoesophageal adenoma in one case. The procedure could thus be successfully completed in ten patients. The overall failure rate was zero in all patients with regard to the underlying disease. There was one temporary, recurrent laryngeal-nerve palsy. The mean overall length of the hospital stay was 3 days. Conclusion: The minimally invasive video-assisted parathyroidectomy for localized single-gland adenoma is a new and attractive surgical therapy option for primary hyperparathyroidism due to improved patient comfort, shortened length of hospital stay and favorable cosmetic results. This may lead to one-day surgery and, therefore, to a reduction of overall costs. Received: 8 December 1998 Accepted: 3 June 1999     

Surgical management of hyperparathyroidism

Primary hyperparathyroidism (PHPT) is a common endocrine condition frequently diagnosed after incidental finding of hypercalcaemia on routine blood tests. This article addresses questions that guide the surgical management of such patients. 1. Is there convincing biochemical diagnosis of primary hyperparathyroidism? Biochemical investigations are detailed and common pitfalls are discussed. 2. Is there an indication to proceed with surgery or could/should the patient be offered medical review and long-term monitoring? The pros and cons for proceeding with parathyroidectomy in distinct patients subgroups are discussed. 3. Do localization studies demonstrate the position of the parathyroid adenoma? The sensitivity of commonly used imaging techniques (sestamibi scan and high-frequency neck ultrasound) is detailed. 4. Is minimally invasive parathyroidectomy feasible? The indications and limitations of a minimally invasive approach are detailed.     

Unilateral open and minimally invasive procedures for primary hyperparathyroidism: a review of selective approaches

The currently established procedure for surgical treatment of primary hyperparathyroidism is bilateral exploration and visualization of all four glands to identify an adenoma and exclude multiglandular disease. With the development of improved preoperative localization imaging of the parathyroids using high-resolution ultrasonography and sestamibi scintigraphy, on the one hand, and perioperative control of surgical success with a rapid parathyroid hormone assay on the other, unilateral and minimally invasive techniques have become feasible. For patients with unequivocal localization in preoperative sestamibi scintigraphy and high-resolution ultrasonography of the parathyroid adenoma in probable single-gland disease, the unilateral and minimally invasive parathyroidectomy present a therapeutic option. Perioperative rapid parathyroid hormone assays, although costly, offer immediate supervision of adenoma extirpation and differentiation of single- and multiglandular disease. These methods demonstrate advantages with favorable cosmetic results and lower reported rate of postoperative hypoparathyroidism. These methods are already being practiced in some places under local anesthesia and in an ambulatory setting. This contribution provides an introduction and overview of the currently practiced unilateral and minimally invasive techniques of parathyroidectomy for primary hyperparathyroidism, discussing indications, advantages and disadvantages, and technical differences in the practiced methods. Received: 26 April 1999 Accepted: 22 November 1999     

Minimally Invasive, Radioguided Surgery for Primary Hyperparathyroidism

Background: Primary hyperparathyroidism affects 1 in 700 individuals in the United States. A single adenoma is responsible in over 85% of cases. Surgery remains the most effective treatment. This study was designed to assess the feasibility of minimally invasive radioguided parathyroidectomy MIRP with confirmation of excision by ex vivo radioactivity alone.Methods: Seventy-five consecutive patients with primary hyperparathyroidism were prospectively studied. Following sestamibi scan, patients underwent unilateral neck exploration guided by a handheld gamma probe, which was also used to measure ex vivo radioactivity of excised tissue.Results: The sestamibi scan was positive in 88% of the patients. A small incision mean, 3.2 ± 0.3 cm was sufficient. Ectopic gland sites were localized in five patients with positive scans and single adenomas. Mean operative time was 48 minutes range, 15–125 minutes, with shorter procedures after the initial 20 cases mean, 24 vs. 72 minutes; P < .01. Radioguided parathyroidectomy was successful in 97%, with a mean follow-up of 11 months range, 1–26 months. As noted previously, adenomatous parathyroid glands contained more than 20% of the background radioactivity.Conclusions: MIRP is a feasible alternative to bilateral dissection with the advantages of guided dissection and rapid confirmation, and may become the procedure of choice for primary hyperparathyroidism.     

Sestamibi SPECT Intensity Scoring System in Sporadic Primary Hyperparathyroidism

Background  Most cases of sporadic primary hyperparathyroidism (PHP) are due to a single parathyroid adenoma and can be treated with minimally invasive parathyroid exploration guided by sestamibi SPECT imaging and intraoperative parathyroid hormone monitoring. Successful surgery depends on identification of the 10–15% of patients with multiglandular disease. Failed initial parathyroid exploration is both costly and morbid. We examined whether a sestamibi SPECT scoring system could predict anatomic findings in patients with PHP. Methods  Prospective data from 1,061 consecutive patients undergoing initial parathyroid exploration for PHP from March 6, 2000 to September 28, 2007 were reviewed. One nuclear medicine physician performed independent blinded review of 577 available dual time-point sestamibi SPECT scans, and scored the results into 1 of 5 categories: 0—negative, 1—possible, 2—probable, 3—definite adenoma, or 4—multiglandular disease. Intraoperative findings and outcomes at >5 months follow-up were examined. Chi-square and nonparametric analyses were used to evaluate variables for correlation. Results  Among patients with sestamibi SPECT scan results classified as either 0—negative or 1—possible adenoma, only 211/262 (81%) had a single adenoma, compared to 263/288 (91%) patients with scan results classified as 2—probable or 3—definite adenoma (p < 0.001). Positive predictive values increased in stepwise correlation with sestamibi SPECT image intensity: 1—possible 78.5%, 2—probable 94.3%, and 3—definite adenoma 98.8%. Multiglandular disease was present in 31/144 (22%) patients with a 0—negative scan versus 13/166 (8%) patients with a 3—definite adenoma scan (p = 0.0005). Only 7/27 (26%) patients with scans classified as 4—multiglandular had actual multiglandular disease. Negative scan results were associated with a greater risk of operative failure (p < 0.001). Conclusions  A simple scoring system based on sestamibi SPECT intensity can predict the likelihood of single adenoma in PHP. Even the best localizing study cannot exclude multiglandular disease preoperatively. Negative sestamibi SPECT scans are associated with a higher rate of operative failure. Because sestamibi SPECT scans of any category do not reliably identify multiglandular disease, expert surgeons must use validated adjuncts to avoid operative failure.     

Negative Imaging Studies for Primary Hyperparathyroidism Are Unavoidable: Correlation of Sestamibi and High-Resolution Ultrasound Scanning with Histological Analysis in 150 Patients

Background Preoperative localization studies with Tc^99m-sestamibi have become an integral step in the preoperative assessment of patients with primary hyperparathyroidism (PHPT). This enables scan-directed minimally invasive parathyroidectomy (MIP) to be the preferred treatment for PHPT in many units. This study aimed to identify factors that lead to negative imaging studies in patients with PHPT. Methods Over a 3-year period consecutive unselected patients with PHPT underwent Tc^99m-sestamibi scanning and high-resolution ultrasound (US) scanning by the same radiologist. When localization studies were concordant, patients underwent MIP. Those patients with negative imaging studies underwent bilateral neck exploration. Histology slides were independently reviewed and the proportion of chief cells and oxyphil cells within each adenoma was estimated. Results One hundred and fifty-eight patients underwent localization studies (38 men and120 women, aged 61.8 ± 15.2 years). Sestamibi scans were negative in 52 (32%) and positive in 106 (68%) patients. There was a higher incidence of hyperplasia in the group of patients with negative sestamibi scans (4 out of 52 vs. 4 out of 103, P < 0.05, χ² test). In patients with negative sestamibi scans the majority of adenomas were formed predominantly from chief cells (26 out of 36) while the majority of patients with adenomas composed predominantly of oxyphil cells had positive scans (21 out of 23) (P < 0.05, χ² test). The weight of parathyroid adenomas was higher when sestamibi scans were positive (median: 1,180 vs. 517 mg, P < 0.05, Student’s t-test). Conclusion Successful preoperative localization of parathyroid adenomas using Tc^99m-sestamibi scanning is influenced by the cytological predominance of individual tumors. Negative scans might therefore be unavoidable in a subgroup of patients.