Mediastinal hyperfunctioning parathyroids: incidence, evolving treatment, and outcome

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.

Video-assisted thoracoscopic surgery for ectopic mediastinal parathyroid tumor: subxiphoid and lateral thoracic approach

Background

This study aimed to investigate the initial results of an endoscopic surgical approach for the treatment of intramediastinal ectopic parathyroid adenoma and to evaluate the effectiveness of a single-incision resection using the subxiphoid approach.

Methods

Five cases of patients (1.89%) were diagnosed with ectopic mediastinal parathyroid tumor and underwent resection from 2008 to 2017 in Fujita Health University Hospital. They were retrospectively analyzed.

Results

Four patients underwent single-port mediastinal tumor resection using the subxiphoid approach and 1 patient underwent multi-port mediastinal tumor resection using the lateral thoracic approach. The operation time was 134±83.52 min, and the amount of blood loss was 81.8±173.41 mL. The rate of conversion to thoracotomy was 0%, and no intraoperative or postoperative complications were observed. The amount of postoperative oral analgesics was 112.83±209.12 tablets, and their administration period was 561.6±1,229.5 days. The length of hospital stay was 4±2.35 days, and the duration of chest tube drainage was 1.33±1.95 days. The patient who underwent multi-port mediastinal tumor resection using the lateral thoracic approach reported postoperative pain. Serum calcium levels decreased from 10.56±1.52 mg/dL preoperatively to 8.96±0.5 mg/dL postoperatively, and serum phosphorous levels increased from 2.84±0.42 mg/dL preoperatively to 3.6±0.51 mg/dL postoperatively. Intact-PTH hormone levels decreased from 221±169.84 pg/dL preoperatively to 70.2±44.28 pg/dL postoperatively. No recurrence of hyperparathyroidism has been observed in any patient.

Conclusions

The single-incision mediastinal tumor resection via the subxiphoid approach, without going through the intercostal space, is considered as a useful endoscopic surgical approach for the treatment of mediastinal ectopic parathyroid adenomas due to the limited occurrence of post-thoracotomy pain syndrome and the superior esthetic outcomes associated with the procedure as compared to thoracotomy and median sternotomy.

Transcervical resection of two parathyroid adenomas located on the anterior mediastinum

The mediastinum is a possible location of ectopic parathyroid adenoma. Most ectopic parathyroid glands in the mediastinum are found in the superior mediastinum within the thymus. In this article, two cases with ectopic mediastinal parathyroid adenomas that were excised via transcervical resection are presented. Preoperative examination of the two cases was performed. Laboratory tests supported hyperparathyroidism. For both patients, the results of radiologic and scintigraphic examinations of the cases were compatible with parathyroid adenoma masses in the anterior mediastinum. Transcervical resection was performed via suprasternal incision through the sternal notch and the posterior wall of the sternum space by blunt dissection with the finger. The soft lesions were removed en bloc in both cases. The parathyroid hormone levels of the two cases decreased dramatically after the operation. Transcervical resection may be an alternative method to major surgery in anterior mediastinal small masses.

Minimally invasive resection for mediastinal ectopic parathyroid glands

BACKGROUND

We reviewed our experience with ectopic mediastinal parathyroidectomy.

METHODS

Between March 1980 and September 2010, mediastinal parathyroidectomy was performed in 33 patients with hypercalcemia secondary to hyperparathyroidism.

RESULTS

Primary hyperparathyroidism was the main diagnosis in 32 patients (97%). Technetium-sestamibi scan was used in 23 (70%) for preoperative localization. Minimally invasive resections were performed in 18 patients (55%), and 15 (45%) underwent open surgery. The most common minimally invasive surgery approach was video-assisted thoracoscopy in 9 patients (27%); the most common open approach was median sternotomy in 11 (33%). Intraoperative parathyroid hormone monitoring was used in 22 patients (67%). The ectopic glands were intrathymic in 15 patients (45%), in the aortopulmonary window in 7 (21%), and in other intrathoracic locations in the remaining 11 (33%). Parathyroid adenomas were identified in 21 patients (64%); parathyroid hyperplasia and carcinoma were identified in 9 (27%) and 3 (9%), respectively. No early mortality occurred in either group. Reoperation was required in 1 patient in the minimally invasive surgery group because of hemothorax. Morbidity occurred in 8 patients (24%), the most common of which was hypocalcemia in 4 (12%). The mean length of stay was significantly shorter in the minimally invasive surgery group (2 versus 6 days; p < 0.001) but mortality and morbidity were not statistically different between the two groups (p = 0.05). Mean follow-up was 3 ± 3.7 years.

CONCLUSIONS

Minimally invasive mediastinal parathyroidectomy has similar outcomes to open surgery, with significantly shorter length of hospital stay.

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.

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.

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

OBJECTIVE

To retrospectively evaluate the feasibility of thoracoscopic removal of mediastinal parathyroids.

SUMMARY BACKGROUND DATA

Mediastinal exploration to resect ectopic parathyroid(s) is needed in approximately 2% of cases in hyperparathyroidism. Recent advances in thoracoscopic surgery allow for a minimally invasive treatment.

METHODS

From 1999 through 2007, 13 patients affected by primary hyperparathyroidism (11 females, mean age 60 years, range: 22-88) underwent thoracoscopic removal of mediastinal parathyroids. Scintigraphy produced positive results in 11 of 13 cases, computed tomography scan in 9 of 10, parathyroid hormone venous sampling in 10 of 10 patients, and magnetic resonance imaging in 5 of 7. Right thoracoscopic access was used in 9 patients, left in 4. Postoperative outcome was analyzed.

RESULTS

Thoracoscopy enabled retrieval of mediastinal parathyroids in 10 of 13 (78%) cases. Mean operating time was 92 minutes (range: 50-240). One procedure (8%) was converted. No perioperative deaths/major complications occurred. Mild complications occurred in 2 of 13 (15%) patients (pneumothorax/pneumonia, transient recurrent nerve palsy). Mean hospital stay was 4.7 days (range: 2-15). At a mean follow-up of 73 months (range: 16-105), parathyroid hormone and calcium venous concentrations were high in 3 patients. Unsuccessful procedures were related to doubtful or non-concordant preoperative localization.

CONCLUSIONS

The thoracoscopic approach for mediastinal parathyroidectomy is feasible and safe. An accurate preoperative work-up should be standardized to avoid useless procedures. In case of negative preoperative localization of the abnormal gland, thoracoscopy should not be adopted as a diagnostic tool.

Utility of positron emission tomography in the mediastinum: moving beyond lung and esophageal cancer staging

PET and PET-CT are rapidly evolving as modalities of thoracic imaging. In the mediastinum, PET can provide information to distinguish thymic hyperplasia from neoplasia, although the use of this imaging for this purpose is not accepted uniformly as necessary. PET is the standard of care in staging and follow-up of mediastinal lymphoma and in follow-up of metastatic seminomas after chemotherapy. Mycobacterial/fungal infections, sarcoidosis, and brown fat can mimic malignant findings on PET in the mediastinum.