Thoracoscopic removal of mediastinal parathyroid glands: a critical appraisal of an emerging technique

Video-Assisted Thoracoscopic Surgery Is a Safe and Feasible Technique for Mediastinal Parathyroid Lesions

Introduction: Hyperfunctional ectopic parathyroid glands in the mediastinum pose a challenge to diagnosis and require optimal surgical management. Video-assisted thoracoscopic surgery (VATS) has emerged as a promising minimally invasive approach, offering potential benefits in terms of both patient comfort and oncological principles. This study aimed to evaluate the effectiveness and safety of VATS for the treatment of hyperfunctional ectopic parathyroid glands in the mediastinum. Methods: Among the 538 patients with mediastinal tumors who underwent thoracoscopic surgery at Istanbul University (2008-2021), 11 exhibited hyperfunctional ectopic parathyroid glands. The localization of the glands was performed using various diagnostic techniques, including neck ultrasound, sestamibi scan, CT (computerized tomography), and SPECT (Single-photon emission computed tomography). VATS (Video-assisted thoracoscopic surgery) was used to remove ectopic parathyroid glands in all 11 patients, with no need for conversion to open surgery. Results: The pathological results showed that VATS successfully removed the ectopic glands in all 11 patients. Serum parathyroid hormone (PTH) levels were monitored intraoperatively, and frozen sections were used to confirm the presence of parathyroid adenomas in all cases. Postoperative analysis showed that PTH levels dropped by at least 50% within 10-15 minutes after adenoma removal. Conclusion: VATS is a safe and effective method for the treatment of hyperfunctional ectopic parathyroid glands in the mediastinum with a low risk of complications.

Robotic resection of ectopic mediastinal parathyroid adenoma in multiple endocrine neoplasia 1

BACKGROUND

Hyperparathyroidism in patients with multiple endocrine neoplasia 1 is attributed to the excessive secretion of parathyroid hormone (PTH) from multiple parathyroid glands. This can be successfully treated through complete resection of the parathyroid glands; however, subsequent surgery is often required because of the presence of supernumerary or ectopic parathyroid glands. Therefore, identifying the locations of all functional glands is crucial for precise resection. Here, we report a case of ectopic mediastinal parathyroid adenoma that was successfully resected using robot-assisted thoracoscopic surgery.

CASE PRESENTATION

A 53-year-old woman underwent a total parathyroidectomy with autotransplantation for multiple endocrine neoplasia 1-associated primary hyperparathyroidism. The patient previously underwent laparoscopic distal pancreatectomy for a pancreatic neuroendocrine tumor. She also presented with a mediastinal tumor and nonfunctional pituitary adenoma that could be followed up. Blood tests before total parathyroidectomy showed high levels of intact PTH (183 pg/mL) and calcium (Ca; 10.3 mg/dL); however, postoperative blood tests still revealed high levels of intact PTH (103 pg/mL) and Ca (11.4 mg/dL). Computed tomography and magnetic resonance imaging revealed a 45-mm-sized mass in the right upper mediastinum as a well-defined solid and cystic lesion, whereas ^99mTc-methoxyisobutylisonitrile scintigraphy indicated a strong accumulation of tracers, suggesting an ectopic lesion in the mediastinum. Persistent hyperparathyroidism after total parathyroidectomy via neck incision was attributed to an ectopic parathyroid tumor in the mediastinum. Thus, we decided to resect the tumor using robot-assisted thoracoscopic surgery to perform the procedure gently and carefully. During surgery, a mediastinal tumor was identified as it was detected radiographically. Because it did not invade the surrounding tissues, it could be completely resected without injuring the capsule. The patient was discharged without complications. Postoperatively, Ca and intact PTH levels decreased back to normal. The final pathological diagnosis confirmed that the mass was an ectopic mediastinal parathyroid adenoma.

CONCLUSIONS

Minimally invasive surgical resection of a remnant ectopic lesion was successfully performed in a patient with multiple endocrine neoplasia 1 using robot-assisted thoracoscopic surgery.

Recurrent renal secondary hyperparathyroidism caused by supernumerary mediastinal parathyroid gland and parathyromatosis: A case report

Background

Surgical parathyroidectomy (PTX) is necessary for patients with severe and progressive secondary hyperparathyroidism (SHPT) refractory to medical treatment. Recurrence of SHPT after PTX is a serious clinical problem. Both supernumerary mediastinal parathyroid gland and parathyromatosis are the rare causes of recurrent renal SHPT. We report a rare case of recurrent renal SHPT due to supernumerary mediastinal parathyroid gland and parathyromatosis.

Case presentation

A 53-year-old man underwent total parathyroidectomy with autotransplantation due to the drug-refractory SHPT 17 years ago. In the last 11 months, the patient experienced symptoms including bone pain and skin itch, and the serum intact parathyroid hormone (iPTH) level elevated to 1,587 pg/ml. Ultrasound detected two hypoechoic lesions located at the dorsal area of right lobe of the thyroid gland, and both lesions presented as characteristics of hyperparathyroidism in contrast-enhanced ultrasound. ^99mTc-MIBI/SPECT detected a nodule in the mediastinum. A reoperation involved a cervicotomy for excising parathyromatosis lesions and the surrounding tissue and a thoracoscopic surgery for resecting a mediastinal parathyroid gland. According to a histological examination, two lesions behind the right thyroid lobe and one lesion in the central region had been defined as parathyromatosis. A nodule in the mediastinum was consistent with hyperplastic parathyroid. The patient remained well for 10 months with alleviated symptoms and stabilized iPTH levels in the range of 123-201 pg/ml.

Conclusion

Although rare, recurrent SHPT may be caused by a coexistence of both supernumerary parathyroid glands and parathyromatosis, which should receive more attention. The combination of imaging modalities is important for reoperative locations of parathyroid lesions. To successfully treat parathyromatosis, all the lesions and the surrounding tissue must be excised. Thoracoscopic surgery is a reliable and safe approach for the resection of ectopic mediastinal parathyroid glands.

Localization and surgical approach to mediastinal parathyroid glands

BACKGROUND

Hyperactive parathyroid glands (PTGs) are in the mediastinum 4.3% of the time. Historically, localization and resection of these glands can be challenging.

METHODS

We searched all operative notes involving a thoracic surgeon and a preoperative diagnosis of hyperparathyroidism from 2001 to 2019.

RESULTS

Eighty-five cases were reviewed, of which 63 were included. Only 14 patients (22%) had de novo hyperparathyroid operations. Seventeen patients (27%) had single-photon emission computed tomography with computed tomography fusion (SPECT-CT) as the only preoperative localization test (excluding chest radiography and ultrasound), and all were resected successfully. The initial surgical approach was transcervical for 16 (27%) patients, however only 7 remained transcervical. 4 (6%) patients had an exploration in which the target lesion was resected but it was not parathyroid tissue.

CONCLUSION

Most patients presenting with mediastinal PTG have had prior HPT surgery. The trend toward more focused HPT surgery may mean more de novo mediastinal PTG resections. An unambiguous functional and anatomic localization test, such as a spect-ct scan, is the best predictor of a successful resection. Ambiguous or discordant scans should be approached cautiously, and additional confirmatory tests are recommended. For suspected PTG located in the thymus, the thoracic surgeon should choose the most familiar approach to achieve complete thymectomy.

Robotic resection of ectopic mediastinal parathyroid adenoma with intraoperative parathyroid hormone monitoring: a case report

Background

Primary hyperparathyroidism is a disease caused by the secretion of excess parathyroid hormone (PTH) owing to the enlargement of the parathyroid gland. Ectopic parathyroid glands exist in the mediastinum in approximately 1–2% of cases, which is relatively rare. Intraoperative monitoring of serum PTH level is important to assess whether the source of hyperparathyroidism has been eliminated.

Case presentation

A 53-year-old asymptomatic woman was diagnosed with ectopic mediastinal parathyroid adenoma. A three-port robotic partial resection of the thymus containing the tumor was attempted, but bleeding from a swollen pericardial diaphragmatic vein led to the addition of an assist port along the way. The PTH level was measured intraoperatively. After confirming that the 15-min PTH level after removal of the tumor was less than 50% of the baseline value, the operation was completed. The tumor was positive for PTH and was diagnosed as an ectopic mediastinal parathyroid adenoma. Some small ectopic parathyroid gland tissues were observed in other parts of the thymic tissue. Serum calcium and PTH levels decreased and normalized.

Conclusions

We report the usefulness of robotic resection for ectopic mediastinal parathyroid adenoma with PTH monitoring. However, histopathologically, small parathyroid gland tissues may remain in the surrounding thymus. Hence, we believe that a strict follow-up is required for parathyroid function in the future.

Hypercalcemic Crisis Secondary to a Superior Mediastinal Parathyroid Adenoma: A Case Report

Hypercalcemic crisis is a rare endocrine emergency that occurs in a small percentage of patients with primary hyperparathyroidism. Although modern diagnostic capabilities allow timely diagnosis and intervention, hypercalcemic crisis still has a high potential for morbidity and mortality. We report an adult patient with a history of kidney stones who presented with heart palpitations, shortness of breath, fatigue, nausea, and 20-pound weight loss over 2 months. Workup revealed hypercalcemia, elevated parathyroid hormone (PTH), and a mediastinal mass on computed tomography angiography. This patient's hypercalcemic crisis was treated with intravenous hydration using normal saline, zoledronate, and furosemide. After medical optimization, the patient underwent definitive treatment with surgical parathyroidectomy via a transcervical approach. At operation, a large parathyroid adenoma was removed from a posterior-superior mediastinal location dorsal to the recurrent laryngeal nerve with subsequent normalization of calcium and PTH. We discuss the timing of parathyroidectomy in cases of hypercalcemic crisis and the surgical approach to ectopic parathyroid glands in the mediastinum.

Preoperative and Intraoperative Methods of Parathyroid Gland Localization and the Diagnosis of Parathyroid Adenomas

Accurate pre-operative determination of parathyroid glands localization is critical in the selection of minimally invasive parathyroidectomy as a surgical treatment approach in patients with primary hyperparathyroidism (PHPT). Its importance cannot be overemphasized as it helps to minimize the harmful side effects associated with damage to the parathyroid glands such as in hypocalcemia, severe hemorrhage or recurrent laryngeal nerve dysfunction. Preoperative and intraoperative methods decrease the incidence of mistakenly injuring the parathyroid glands and allow for the timely diagnosis of various abnormalities, including parathyroid adenomas. This article reviews 139 studies conducted between 1970 and 2020 (49 years). Studies that were reviewed focused on several techniques including application of carbon nanoparticles, carbon nanoparticles with technetium sestamibi (99m Tc-MIBI), Raman spectroscopy, near-infrared autofluorescence, dynamic optical contrast imaging, laser speckle contrast imaging, shear wave elastography, and indocyanine green to test their potential in providing proper parathyroid glands' localization. Apart from reviewing the aforementioned techniques, this study focused on the applications that helped in the detection of parathyroid adenomas. Results suggest that applying all the reviewed techniques significantly improves the possibility of providing proper localization of parathyroid glands, and the application of indocyanine green has proven to be the 'ideal' approach for the diagnosis of parathyroid adenomas.

Main Surgical Principles and Methods in Surgical Treatment of Primary Hyperparathyroidism

The only curative treatment for primary hyperparathyroidism (pHPT) is surgery. The most important factors that increase the success rate of a parathyroidectomy are the establishment of the correct diagnosis and the surgeon's good knowledge of anatomy and embryology. The lower parathyroid glands develop from the dorsal portion of the third pharyngeal pouch, and the upper parathyroid glands from the fourth pharyngeal pouch. Humans typically have 4 parathyroid glands; however, more than 4 and fewer than 4 have been observed. Typically, the upper parathyroid glands are located in the cricothyroid junction area on the posterolateral portion of the middle and upper third of the thyroid, while the lower parathyroids are located in an area 1 cm in diameter located posterior, lateral, or anterolateral to the lower thyroid pole. Ectopic locations of parathyroid glands outside the normal anatomical regions due to the abnormal migration during embryological development or acquired ectopy due to migration of enlarged parathyroids are not uncommon. There are various surgical techniques to treat HPT; however, 2 main surgical options are used: bilateral neck exploration (BNE) and minimally invasive parathyroidectomy (MIP). While there are open, endoscopic, and video-assisted MIP (MIVAP) approaches, most often an open lateral MIP technique is used. In addition, endoscopic or robotic parathyroidectomy methods performed from remote regions outside the neck have been reported. Although currently MIP is the standard treatment option in selected patients with positive imaging, BNE remains the gold standard procedure in parathyroid surgery. In 80% to 90% of patients with pHPT, a pathological parathyroid gland can be detected with preoperative imaging methods and MIP can be applied. However, the pathological gland may not be found during a MIP procedure as a result of false positive results. The parathyroid surgeon must also know the BNE technique and be able to switch to BNE and change the surgical strategy if necessary. If the intended gland is not found in its normal anatomical site, possible embryological and acquired ectopic locations should be investigated. It should be kept in mind that MIP and BNE are not alternatives to each other, but rather complementary techniques for successful treatment in parathyroid surgery.

Video-assisted thoracoscopic surgery for ectopic mediastinal parathyroid adenoma

Background

Primary hyperparathyroidism (PHPT), caused by an ectopic mediastinal parathyroid adenoma, is uncommon. In the past, when the adenoma was not accessible from the neck, median sternotomy was advocated for safe and successful parathyroidectomy. Video‐assisted thoracoscopic surgical (VATS) parathyroidectomy represents a modern alternative approach to this problem.

Methods

Information on patients undergoing VATS was obtained from a specific database, including clinical presentation, biochemistry, preoperative imaging, surgical approach and patient outcomes. A comprehensive literature review was undertaken to draw comparisons with other publications.

Results

Over a 2‐year period, nine patients underwent VATS parathyroidectomy for sporadic PHPT. Five patients had persistent PHPT following previous unsuccessful parathyroidectomy via cervicotomy, and four had had no previous parathyroid surgery. The median duration of surgery was 90 (range 60–160) min. Eight patients were cured biochemically, with no major complications. One patient required conversion to a median sternotomy for removal of a thymoma that had resulted in false‐positive preoperative imaging.

Conclusion

With appropriate preoperative imaging, multidisciplinary input and expertise, VATS parathyroidectomy is an effective, safe and well tolerated approach to ectopic mediastinal parathyroid adenoma.

Comparison of the perioperative outcomes in antero-superior mediastinal tumor resection performed by transcervical resection and video-assisted thoracoscopic surgery

Background

It remains controversial that whether transcervical resection (TC) was associated with better outcomes than video-assisted thoracoscopic surgery (VATS) in the treatment of antero-superior mediastinal tumors. We aimed to compare the safety and reliability between TC and VATS.

Methods

Between 2010 and 2012, 80 consecutive patients underwent antero-superior mediastinal tumor resection via TC (n=31) or VATS (n=49). Perioperative outcomes were compared. A propensity score-matched analysis was performed to control the potential confounders.

Results

A total of 41 men and 39 women with median age of 52.5 years were enrolled. No patient died during the perioperative course. After propensity matching, TC group was associated with less intraoperative blood loss (35.1±18.7 vs. 93.7±136.1 mL, P=0.034), less postoperative drainage (65.6±76.8 vs. 335.0±154.9 mL, P<0.001), shorter length of postoperative hospital stay (3.2±1.2 vs. 4.1±1.3 days, P=0.003) and less hospitalization expense (22,252.3±4,761.7 vs. 26,514.2±4,052.8 CNY, P=0.002) compared to VATS group. One patient with VATS was converted to open surgery due to intraoperative vessels damage. The postoperative complication was null in TC group while it was 6.1% (n=3) in VATS group (P=0.279), including 1 case of prolonged chest tube drainage and 2 cases of recurrent laryngeal nerve injury.

Conclusions

TC for antero-superior mediastinal tumors is a safe procedure with better perioperative outcomes compared to VATS.

Thoracoscopic removal of ectopic mediastinal parathyroid adenoma causing hyperparathyroidism: a rare entity

Ectopic mediastinal parathyroid adenomas are uncommon. Here, we report the successful thoracoscopic removal of a mediastinal parathyroid adenoma from a patient with hypercalcemia. A 58-year-old female patient was referred to our department with persistent hypercalcemia. Serum calcium and phosphorus levels were 13.2 mg/dl and 2.5 mg/dl respectively, while the intact parathormone level was 798.9 pg/ml. Parathyroid computed tomography revealed a solid and well-defined mass at the anterior mediastinum close to the distal aorta. Once the contrast was enhanced, our pre-diagnosis was ectopic parathyroid adenoma. The mass was detected at the anterior mediastinum, dissected free from the surrounding tissue and excised. The capsulated mass, which had a diameter of 3 × 1.5 × 0.7 cm, was confirmed as parathyroid adenoma histopathologically. Postoperative calcium and parathormone levels decreased dramatically to normal levels. Anterior mediastinal localization of an ectopic parathyroid adenoma is a rare entity. The transsternal approach is the most preferred method, but video-thoracoscopy can be used safely and effectively.

Combined use of a nanocarbon suspension and 99mTc-MIBI for the intra-operative localization of the parathyroid glands

OBJECTIVE

To investigate the combined use of a nanocarbon (NC) suspension and low-dose ^99mTc-MIBI for parathyroid localization during surgery in patients with secondary hyperparathyroidism (sHPT).

METHODS

Between March 2010 and September 2015, 40 patients with sHPT were enrolled in this study and were randomized to receive either low-dose ^99mTc-MIBI+NC (group I) or low-dose ^99mTc-MIBI (group II). Pre- and post-operative serum levels of intact PTH (iPTH), calcium and phosphorus between groups were compared and the intra-operative radioactive counts of the parathyroid glands were measured.

RESULTS

The post-operative iPTH level was significantly lower in patients of group I (24.2±31ng/L) than in those of group II (106±155ng/L) (P=0.03) while there were no significant differences in intra-operative parathyroid gland radioactive counts between the groups. The duration of the surgical procedure was shorter for patients of group I than patients of group II. There were no serious intra-operative or post-operative complications.

CONCLUSION

The combined use of an NC suspension and ^99mTc-MIBI for patients with sHPT is strongly recommended for the localization of parathyroid glands during surgery and is likely to improve clinical outcomes for patients.

Prevertebral cervical approach: a pure endoscopic surgical technique for posterior mediastinum parathyroid adenomas

BACKGROUND

Parathyroid gland mediastinal ectopia is an unusual but challenging condition in surgical management of hyperparathyroidism. Posterior mediastinum parathyroid ectopia is rare, and glands need to be removed either with a broad open cervical or thoracic approach. In recent years, several minimally invasive approaches to mediastinal parathyroid glands have been described, but for posterior mediastinum adenomas, proposed techniques are transthoracic.

METHODS

The aim of this paper is to describe, to our best knowledge for the first time, a standardized pure endoscopic cervical technique to approach posterior mediastinal parathyroid adenomas which we have used in three patients.

RESULTS

The technique was applied in three patients which excellent surgical, postoperative, and cosmetic results.

CONCLUSIONS

Endoscopic prevertebral approach is a feasible, sure and inexpensive standardized pure endoscopic cervical approach to posterior mediastinal parathyroid adenomas, which may result in a less aggressive surgical option when compared with thoracic approaches.

Endoscopic and robotic parathyroidectomy in patients with primary hyperparathyroidism

Primary hyperparathyroidism (PHPT) is one of the most common endocrine disorders for which parathyroidectomy is the most effective therapy. Until late 1970s, the standard approach to parathyroidectomy was a four-gland exploration using a large skin incision. However, 80 to 85 percent of cases of PHPT are caused by a single adenoma. As such, the concept of performing a bilateral exploration in order to visualize all four glands has been argued to be excessive since in the majority of cases, there is only one abnormal gland. Focused exploration (one gland) is currently the standard technique for parathyroidectomy worldwide. Despite a rapid acceptance of minimally invasive approaches in most endocrine surgery centers, the use of an endoscope with or without the use of a robotic system to perform parathyroidectomy remains controversial. The goal of this study was to review current available data about surgical approaches using an endoscope with or without the use of a robotic system in the management of patients with PHPT. For conventional endoscopic and video assisted parathyroidectomy, several comparative studies have demonstrated some advantages in terms of reduced postoperative pain, better cosmetic results and higher patient satisfaction compared to open non-endoscopic minimally invasive parathyroidectomy. Robot-assisted transaxillary parathyroidectomy has the advantage of leaving no scar in the neck but its role has not yet been delineated clearly given the limited number of published series. Subjective postoperative cosmetic evaluation is good by concealing the scar in the axilla or infraclavicular area. However, this approach is associated with more extensive dissection than during conventional open or endoscopic neck access surgical procedures. Patients with true ectopic mediastinal parathyroid glands are good candidates for conventional or robot-assisted thoracoscopic approaches because these glands are in remote and narrow anatomical locations.

Mediastinal parathyroid adenomas and their surgical implications

Primary hyperparathyroidism is a relatively common problem encountered by any endocrine surgical unit. Ectopic parathyroid adenomas have been known to be a common cause of persistent hyperparathyroidism after surgery. A common site of the missed ectopic gland will be that in the mediastinum. However, with the increasing improvement in available imaging, it is likely that this can be diagnosed preoperatively. The surgical approach to the mediastinal parathyroid has also changed vastly over the last decade from maximally invasive to minimally invasive with minimal complications. We provide a review on the entity of mediastinal parathyroid adenomas and their surgical implications.

Mediastinal Parathyroid Adenoma with Osteitis Fibrosis Cystica: Robot-Assisted Thoracic Surgical Resection

Mediastinal parathyroid adenomas can be resected by sternotomy or video-assisted thoracoscopic surgery. Robot-assisted thoracic surgical approaches have recently been described. We report robotassisted thoracic surgical resection of a mediastinal parathyroid in a morbidly obese patient. Additional comorbidities included multiple pathological fractures related to hypercalcemia. Intraoperative parathyroid hormone levels confirmed successful removal of the adenoma. Hungry bone syndrome developed after surgery but eventually resolved. Robotassisted thoracic surgery avoided the need for sternotomy and associated concerns related to poor bone healing. Robot-assisted thoracic surgery has potential advantages over video-assisted thoracoscopic surgery in patients with obesity because of easier instrument articulation within the thoracic cavity rather than at the chest wall.

High cardiac background activity limits 99mTc-MIBI radioguided surgery in aortopulmonary window parathyroid adenomas

BACKGROUND

Radioguided surgery using 99m-Technetium-methoxyisobutylisonitrile (99mTc-MIBI) has been recommended for the surgical treatment of mediastinal parathyroid adenomas. However, high myocardial 99mTc-MIBI uptake may limit the feasibility of radioguided surgery in aortopulmonary window parathyroid adenoma.

CASE PRESENTATION

Two female patients aged 72 (#1) and 79 years (#2) with primary hyperparathyroidism caused by parathyroid adenomas in the aortopulmonary window were operated by transsternal radioguided surgery. After intravenous injection of 370 MBq 99mTc-MIBI at start of surgery, the maximum radioactive intensity (as counts per second) was measured over several body regions using a gamma probe before and after removal of the parathyroid adenoma. Relative radioactivity was calculated in relation to the measured ex vivo radioactivity of the adenoma, which was set to 1.0. Both patients were cured by uneventful removal of aortopulmonary window parathyroid adenomas of 4400 (#1) and 985 mg (#2). Biochemical cure was documented by intraoperative measurement of parathyroid hormone as well as follow-up examination. Ex vivo radioactivity over the parathyroid adenomas was 196 (#1) and 855 counts per second (#2). Before parathyroidectomy, relative radioactivity over the aortopulmonary window versus the heart was found at 1.3 versus 2.6 (#1) and 1.8 versus 4.8 (#2). After removal of the adenomas, radioactivity within the aortopulmonary window was only slightly reduced.

CONCLUSION

High myocardial uptake of 99mTc-MIBI limits the feasibility of radioguided surgery in aortopulmonary parathyroid adenoma.

Gamma probe-assisted excision of an ectopic parathyroid adenoma located within the thymus: case report and review of the literature

Primary hyperparathyroidism due to parathyroid adenomas may be associated with ectopic parathyroid gland localization in 20-25% of the patients. We report herein the excision of an ectopic parathyroid adenoma which was detected in the thymus gland by gamma probe intraoperatively. A 38-year-old patient presented to our clinic with a history of bilateral nephrolithiasis, chronic hypercalcaemia, and PTH elevation. A combination of Technetium-99 m sestamibi scintigraphy and Computed Tomography scan of the chest and neck revealed an ectopic parathyroid adenoma of 8.5 mm in its greatest dimension. The patient underwent sternotomy and the adenoma was found within the right lobe of the thymus gland with the intraoperative use of gamma probe. PTH detection and frozen biopsy were performed during surgery and confirmed the successful excision of the adenoma, while mild hypocalcaemia was noticed postoperatively. We conclude that accurate preoperative and intraoperative localization of an ectopic parathyroid adenoma is crucial to successful surgery. The use of at least two diagnostic modalities before surgical excision minimizes the risk of re-operation for recurrent hyperparathyroidism, while the intraoperative use of gamma probe offers a significant advantage over conventional techniques by reducing surgical time, morbidity and/or complications associated with surgical exploration.

Focused approach to ectopic mediastinal parathyroid surgery assisted by radio-guided navigation

PURPOSE

Surgical removal of a mediastinal ectopic parathyroid is always challenging. We attempted to apply intraoperative radio-guided navigation for the minimally invasive focused removal of ectopic hyperparathyroid lesions in the mediastinum, and evaluated its significance.

METHODS

Five cases with ectopic mediastinal hyperfunctioning parathyroid were treated by intraoperative radio-guided navigation surgery. MIBI (methoxyisobutylisonitrile)-SPECT (single-photon emission computed tomography) was used to plan the surgical approach. (99m)Tc-MIBI (11.1 MBq/kg) was administered 2 h before surgery, and a handheld gamma probe was used intraoperatively to detect radioactivity in the lesion.

RESULTS

Two lesions found on the aortic arch were excised by left thoracoscopic resection. Two other lesions on the tracheal bifurcation were approached by right thoracotomy. We could remove two hidden adenomas by en bloc resection with the adjacent lymph nodes under radio-guidance. Another lesion, located at the ligamentum arteriosum, was excised with sternal division. Accumulations of radioactivity were identified in all lesions removed, with decreased radioactivity in the surgical field.

CONCLUSIONS

Intraoperative radio-guided navigation is a useful tool for the focused removal of an ectopic mediastinal parathyroid by providing instant feedback to help guide the surgeon, while also providing precise localization of lesions.

Optimizing the minimally invasive approach to mediastinal parathyroid adenomas

BACKGROUND

Patients with refractory hyperparathyroidism after neck exploration may have a mediastinal parathyroid gland that has not been identified reliably with a single radiologic study. We report 17 patients who underwent minimally invasive resection for mediastinal parathyroid adenomas after confirmatory multipoint radiologic imaging.

METHODS

Fifteen patients underwent thoracoscopic procedures and 2 patients underwent mediastinoscopic procedures for resection of suspected mediastinal parathyroid adenoma. Preoperative localizing studies included sestamibi scan, computed tomography scan of the neck and chest, and selective venous sampling of parathyroid hormone levels. Once a mediastinal location was determined, thoracoscopic or mediastinoscopic resection was performed. Successful removal of parathyroid tissue was confirmed with a 50% or greater reduction in intraoperative parathyroid hormone levels.

RESULTS

Parathyroid adenoma was resected in 88% of patients after the operation. The cure rate was 100% in patients with two or more concordant studies locating parathyroid tissue in the mediastinum and 60% in those with one positive study. The thoracostomy tube was removed on median postoperative day 1 (range, 0 to 2 days). Median hospital stay was 3 days (range, 2 to 7 days). The most common complication was temporary hypocalcemia, which occurred in 18% of patients.

CONCLUSIONS

Minimally invasive parathyroidectomy is an effective treatment of hyperparathyroidism caused by mediastinal parathyroid tissue. Targeted exploration depends on the guidance of preoperative localization studies and measurement of intraoperative parathyroid hormone levels to verify successful resection. Selective venous sampling and high-resolution computed tomography scanning can be helpful in patients with negative sestamibi scans.

[Intraoperative parathyroid hormone determination for primary hyperparathyroidism]

Intraoperative parathyroid hormone measurement (IOPTH) has proved to be an important promoter for focused and minimally invasive parathyroidectomy procedures in primary hyperparathyroidism. IOPTH enables multiglandular disease to be excluded with a high degree of certainty at the time of operation. The choice of the cut-off value for IOPTH as the criterion for success is of utmost importance with respect to the prognosis for operative success (biochemical healing). Advantages and disadvantages of the variety of existing IOPTH success criteria are confusing and their assessment is contradictory. Particularly with respect to cost-benefit aspects the standard application of IOPTH as "biochemical frozen section" even in conventional open parathyroidectomy remains a matter of controversy. This article gives an up-date on current knowledge and provides practical guidelines for clinical use of IOPTH.

The results of surgery for mediastinal parathyroid tumors: a comparative study of 63 patients

PURPOSE

Parathyroidectomy for ectopic mediastinal hyperfunctioning glands could be performed by transcervical approach, sternotomy, thoracotomy, and recently by thoracoscopic and mediastinoscopic approaches. This study was aimed to analyze the results of traditional and video-assisted parathyroidectomy for mediastinal benign hyperfunctioning glands.

METHODS

Fifty-one upper mediastinal exploration by a conventional cervicotomy, 12 by video-assisted approaches (two thoracoscopy and 10 transcervical mediastinoscopy) and six by sternotomy were performed in 63 patients with primary hyperparathyroidism.

RESULTS

Video-assisted and sternotomic parathyroid explorations achieved biochemical cure in all cases; following conventional transcervical mediastinal exploration, a persistent hyperparathyroidism occurred in 11.8% of patients, who were subsequently cured by sternotomic approach. No complications occurred after video-assisted parathyroidectomy, while an overall morbidity rate of 50% and 10% was found after sternotomic and conventional cervicotomic approaches. Postoperative pain and hospital stay were significantly increased following sternotomy; patient's subjective cosmetic satisfaction was significantly higher after video-assisted and conventional cervicotomic approaches.

CONCLUSIONS

Conventional cervicotomic parathyroidectomy may achieve satisfactory results, especially for upper mediastinal glands. Sternotomic approaches are effective, but should be limited because of invasiveness and increased morbidity. In case of deep and lower hyperfunctioning mediastinal parathyroids, video-assisted approaches represent a less invasive, effective, and safe alternative and might be the technique of choice.