Parathyroid Scan Research Articles

MIBI SPECT Scan and Ultrasonography in Preoperative Imaging of Primary Hyperparathyroidism

Objectives: In patients who have parathyroid adenoma, combination of ultrasonography and technetium Tc 99m sestamethoxyisobutylisonitrile scan (also called sestamibi or MIBI scan), which allows anatomic and functional information about parathyroid adenomas, is used commonly to maximize operative cure. The sensitivity of MIBI scan may be increased by adding single photon emission computed tomography (SPECT) and computed tomography (CT) as a combined MIBI-SPECT CT scan. We assessed the accuracy of ultrasonography and parathyroid MIBISPECT scan in detecting parathyroid adenoma and evaluated the potential benefit of the combined protocol of ultrasonography and MIBI-SPECT parathyroid scan. Methods: In 58 patients who had biochemical evidence of primary hyperparathyroidism, we retrospectively reviewed the preoperative ultrasonography and MIBI-SPECT scans. The results of these studies were correlated with surgical findings. Results: In the 58 patients, surgery showed that 43 patients (74%) had solitary parathyroid adenoma. The sensitivity, specificity and accuracy of MIBI-SPECT for parathyroid adenoma was (72%,80%,74%) and for ultrasonography (53%,60%,55%) respectively. The highest sensitivity is noted with the combination of MIBI-SPECT and ultrasonography (79%), . 9 adenomas (21%) were missed by both modalities. In the 20 adenomas that were missed by ultrasound 11 were detected by MIBI SPECT. Conclusion: The MIBI-SPECT had better performance than ultrasonography for parathyroid adenoma localization. The combined MIBI SPECT and ultrasonography has the highest sensitivity for parathyroid adenoma detection (79%). An alternative strategy may be to use MIBI-SPECT initially, and to proceed to ultrasonography only in patients with negative MIBI- SPECT. This may avoid many ultrasonography procedures.

Implications of Unexpected Diffuse Lung Uptake on a 99mTc-Sestimibi Parathyroid Scan

Diffuse (99m)Tc-sestimibi uptake in the lungs is a sign of serious pathology and merits further work-up. We present a case in which diffuse lung uptake was incidentally found on a parathyroid scan.

Management of Primary Hyperparathyroidism in a VAMC Health System: Evidence‐Based Management Protocol and Future Directions

Objectives: (1) Establish a best practices guideline for the surgical treatment of primary hyperparathyroidism within the context of single hospital system. (2) Stratify the group of patients who underwent directed excision by the accuracy of preoperative localization studies, and whether intraoperative techniques impacted cure, and at what resource costs. Methods: In this retrospective chart review, patients were identified by searching all parathyroid-related procedures that took place at our institution from January 1, 2002, to December 31, 2013. Information related to the aims of the study, including demographics, operative details, and laboratory values were recorded, and imaging studies were reviewed by the senior investigator. Results: Of those patients with preoperative localization and directed excision, the preoperative studies most predictive of cure were a combination of Sestamibi parathyroid scan and surgeon-performed ultrasound. When these were in disagreement, surgical findings supported the ultrasound results. Intraoperative parathyroid hormone rapid assay was helpful in predicting cure, but added 68 minutes to the operating time on average. Most patients were surgically cured, and of the few patients with persistent high parathyroid hormone levels, vitamin D deficiency was the primary associated lab abnormality. Conclusions: Analysis of techniques that predict a surgical cure allowed the development of a best practices algorithm that includes the following: (1) Obtain 2 preoperative localization studies, including a surgeon-performed ultrasound; (2) Obtain preoperative vitamin D levels and supplement as indicated; and (3) Reserve intraoperative parathyroid hormone assay only for those patients who do NOT have 2 corroborating localization studies.

Functional evaluation of parathyroid adenoma using 99mTc-MIBI parathyroid SPECT/CT

In parathyroid adenoma, uptake of technetium-99m-methoxyisobutylisonitrile ((99m)Tc-MIBI) has been suggested to have a correlation with functional markers. The purpose of this study was to evaluate the feasibility of (99m)Tc-MIBI parathyroid single photon emission computed tomography/computed tomography (SPECT/CT) in evaluating the function and disease severity of parathyroid adenoma. Twenty-three patients with surgically confirmed parathyroid adenoma were retrospectively enrolled. A parathyroid planar scan and SPECT/CT were performed before parathyroidectomy. Functional and clinical makers reflecting the disease severity of parathyroid adenoma were also evaluated, including serum intact parathyroid hormone, calcium, bone mineral density, and creatinine clearance. The pathologic volume (V(P)) of the adenoma was measured after parathyroidectomy. On parathyroid SPECT/CT, metabolic volume (V(M)) was measured using an isocontour method. Maximum uptakes of parathyroid adenoma and mean uptakes of contralateral thyroid tissue were measured to calculate the parathyroid adenoma-to-background ratio on parathyroid SPECT/CT (PBR(SCT)) and planar scan (PBR(PL)). V(M) significantly correlated with V(P) (r=0.669, P=0.0005). Serum intact parathyroid hormone level significantly correlated with PBR(PL), PBR(SCT), V(M), and V(P) (P=0.0004, 0.005, 0.003, and 0.025, respectively). However, serum calcium level correlated only with V(M) (P=0.012). Regarding the surgical indication criteria, PBR(SCT) and PBR(PL) were significantly higher in the young-aged group (P=0.0004 and 0.024, respectively) and V(M) was significantly higher in the high calcium level group (P=0.049), whereas V(P) was not different between groups on the basis of any criteria. Quantitative indices of parathyroid SPECT/CT closely correlate with laboratory functional markers and disease severity of parathyroid adenoma. Thus, parathyroid SPECT/CT could be used for evaluation of the underlying functional state and disease severity of parathyroid adenoma, particularly for decision pertaining to surgical treatment.

Parathyroid nuclear scan. A focused review on the technical and biological factors affecting its outcome

Technetium Parathyroid Scintigraphy (TS) is the most popular noninvasive localization procedure in patients with primary hyperparathyroidism (PHPT). Awareness of various factors involved in technetium uptake helps understand the outcome of TS. We utilize a case of changing TS scans in a patient to review the literature on the various biological and technical factors involved in technetium uptake by the abnormal parathyroid tissue. A 56 year female was diagnosed with PHPT and osteopenia. An initial scan using (99m)Tc-Tetrofosmin showed no definite areas of abnormal parathyroid tissue. Patient refused surgical exploration, was started on Bisphosponates and subsequently monitored. Five years later she suffered fracture of her right wrist. A repeat TS using (99m)Tc-Sestamibi revealed hypervascular parathyroid lesion in the right lower neck. She underwent successful removal of a right lower parathyroid adenoma. Technical factors like the type of Tc isotope used, imaging techniques and biological factors like biochemical parameters (calcium, vitamin D levels), adenoma size, content of oxyphilic cells, vascularity can affect the outcome of the scan. Clinicians should be aware of technical and biological factors that could result in negative scan in parathyroid nuclear scintigraphy.

Radio-guided Surgery of a Patient with Secondary Hyperparathyroidism: The Clinical Impact on the Duration of Surgery in Renal Failure Patient

Secondary hyperparathyroidism is consequent to a chronic hypocalcaemic condition that can be caused primarily by renal failure. As a result of continuous stimulus to produce and secrete PTH induces parathyroid gland hyperplasia. In this case report, we present a chronic renal failure patient with high parathyroid hormon level suspected for secondary hyperparathyroidism. According to the parathyroid scan findings four glands were demonstrated concordant with parathyroid pathology and the patient was operated with intra- operative gamma probe in a very short time. Radio-guided surgery of this renal failure patient by using intra-operative gamma probe for excision of hyperplastic parathyroid glands and hereby shortening the surgery time, provided a positive impact of renal residual function of this dialysis patient. Although, radioguided surgery with minimal invasive surgery is commonly recommended for primary hyperparathyroidism with single adenoma, we recomment radioguided surgery of hyperplastic parathyroid glands especially in renal failure patients for maintaining renal residual function.

Safety and success of parathyroidectomy under local anaesthesia with the classical anterior cervical approach

أهداف البحث استئصال الدريقات (جنيب الدرقية) هو إجراء شائع إلى حد ما، ويؤدى في معظم المراكز المرجعية في أنحاء العالم. في هذه الورقة العلمية عملنا على تقييم جدوى إجراء هذه العملية تحت التخدير الموضعي بدلا من التخدير العام وذلك من حيث السلامة، ونجاح الاستئصال، ومضاعفات ما بعد العملية. طرق البحث أجريت الدراسة في الفترة بين عامي 2006م و 2008م، حيث خضع 22 من المرضى لاستئصال الدريقات تحت التخدير الموضعي في مستشفانا، وكان قد خضع كل المرضى لمسح الدريقات النووي (السيستاميبي) كوسيلة رئيسة لتحديد موقع الدريقة مفرطة الإفراز كما تأكد التشخيص باستخدام مستوى هرمون الدريقات قبل وبعد العملية واعتمد التشخيص النهائي على الفحص التشريحي المرضى (الباثولوجي). النتائج كان الإجراء ناجحا في 21 حالة من أصل 22 حالة وأعمار المرضى تراوحت بين 22 و 74عاما بمتوسط 55.3 ± 11.3 عاما، واحتاج مريض واحد إعادة الاستكشاف تحت تخدير عام في أعقاب العملية الأولى، وكان عدد الدريقات التي أزيلت هو (دريقة واحدة) من 20 مريضا وثلاث من مريض واحد فقط. كان التشريح المرضي (ورم غدي) عند 15 من 22 مريضا، وتضخم وفرط الإفراز عند مريضين، وعند أربع حالات كان التشخيص النهائي مشكوك فيه بين الحالتين. استغرق إجراء العملية ما بين 20 – 60 دقيقة بمتوسط 32.5 دقيقة. ولم تسجل أي مضاعفات للعمليات الجراحية كالقيلة أو إصابة العصب الحنجري بين مرضانا. كما تقبل جميع المرضى التخدير الموضعي، والألم, وتعاونوا بشكل كامل. الاستنتاجات : يمكن إجراء استئصال الدريقات بأمان تحت التخدير الموضعي، مع نسبة نجاح عالية، وانخفاض الوقت اللازم للإجراء الجراحي، وكذلك انخفاض مضاعفات ما بعد الجراحة. الكلمات المفتاحية استئصال الدريقات; التخدير الموضعي; فرط إفراز الدريقات الأولي. Parathyroidectomy is a fairly common procedure in referral centres all over the world. We evaluated the feasibility of performing parathyroidectomy under local anaesthesia instead of general anaesthesia, from the point of view of safety, success and postoperative complications. Between 2006 and 2008, 22 patients aged 22–74 years (mean, 55.3 ± 11.3 years) underwent parathyroidectomy for primary hyperparathyroidism under local anaesthesia at Notre-Dame Hospital, Montreal, Canada. All the patients had a Sestamibi parathyroid scan to localize the hypersecreting gland(s). Diagnosis was confirmed by a rapid test for parathyroid hormone and the final histopathological findings. The procedure was successful in 21 of the 22 cases. One patient required re-exploration under general anaesthesia in subsequent surgery. One gland was removed from 20 patients and three from only one patient. The diagnosis was an adenoma in 15/22 patients, hyperplasia in 2/22 and undetermined in 4/22. The operating time was 20–60 min (mean, 32.5 min). No post-operative haematomas or recurrent laryngeal nerve injury was reported. Pain control and patient tolerance and cooperation were achieved in all cases. Parathyroidectomy can be performed safely under local anaesthesia, with a high success rate and reduced operative time as well as fewer postoperative complications.

Is minimally invasive parathyroid surgery an option for patients with gestational primary hyperparathyroidism?

BackgroundGestational primary hyperparathyroidism is associated with serious maternal and neonatal complications, which require prompt surgical treatment. Minimally invasive parathyroidectomy reduces pain, improves cosmesis and may achieve cure rates comparable to traditional open bilateral neck exploration. We report the clinical course of a woman with newly diagnosed gestational primary hyperparathyroidism and discuss the decision making behind the choice of video-assisted minimally invasive parathyroidectomy, amongst the other minimally invasive parathyroidectomy techniques available.Case presentationA 38-years-old pregnant woman at 9 weeks of gestation, with severe hyperemesis and hypercalcaemia secondary to gestational primary hyperparathyroidism (ionised calcium 1.28 mmol/l) was referred for surgery. Ultrasound examination of her neck identified 2 suspicious parathyroid enlargements. In view of pregnancy, a radioisotope Sestamibi parathyroid scan was not performed. Bilateral four-gland exploration was therefore deemed necessary to guarantee cure. This was performed with video-assisted minimally invasive parathyroidectomy, which relies on a single 15 mm central incision with external retraction and endoscopic magnification, allowing bilateral neck exploration.Surgery was performed at 23 weeks of gestation. Four glands were identified in orthotopic positions of which three had normal appearance. The fourth was a right superior parathyroid adenoma of 756 mg. Ionized calcium (1.12 mmol/l) and PTH (0.9 pmol/l) normalised postoperatively. Patient was discharged on the second postoperative day, needing no pain relief. Cosmetic result was excellent. Her pregnancy progressed normally and she delivered a healthy baby.ConclusionVideo-assisted minimally invasive parathyroidectomy allows bilateral four-gland exploration, and is an optimal technique to treat gestational primary hyperparathyroidism. This procedure removes the need for radiation exposure, reduces pain, improves cosmesis and may achieve cure rates comparable to traditional open bilateral neck exploration.

Non-visualized Thyroid Gland by Tc-99m MIBI Scan with Normal Thyroid Scan.

We present the case of a 21-year-old man who was referred to us for parathyroid scintigraphy with high blood levels of intact parathormone and osteoporosis. Several methods and radiopharmaceuticals, e.g., Tc-99m MIBI and Tl-201 chloride/Tc-99m pertechnetate (Tl-201/TcPO−4) subtraction, are commonly used for this purpose. We present the case of a thyroid gland that demonstrates quite normal Tc-99m pertechnetate uptake, no accumulation of Tc-99m MIBI, and very low grade Tl-201 uptake. To the best of our knowledge, no similar case has been reported previously. A 21-year-old male with osteoporosis and growth-development retardation was referred for MIBI parathyroid scan because of high blood levels of intact parathormone and bone-specific alkaline-phosphatase, which were 219.4 (15–88 pg/ml) and 355 (21–58 U/L), respectively. In his Tc-99m pertechnetate (TcPO−4) pinhole scintigraphy, bilateral clearly visualized radioactivity accumulation in the thyroid gland was seen (Fig. 1a). In both early or late images of the Tc-99m MIBI parathyroid scan, the thyroid gland was not visualized (Fig. 1b). Therefore, a Tl-201/TcPO−4 subtraction scan method was used. However, the Tl-201 accumulation level in the thyroid gland was not sufficient for the subtraction method (Fig. 1c). In his thyroid ultrasonography, the thyroid gland echo was homogenous, and there was neither any solid nor cystic lesion. The physical examination of his neck was normal. Other laboratory findings were all normal as follows. TSH: 3.03 (0.35–5.6 IU/mL), free T3: 3.66 (2.5–3.9 pg/mL), free T4: 0.90 (0.59–1.3 ng/dL), Anti-TPO:0.3 (0–40 IU/mL), Anti-TG-Ab: <2.2 (0- + u/L), TSH receptor Ab: 1.0 (0–14 U/L), osteocalcine: 9.13 (1.5–15 ng/dL), growth hormone: 1.3 (0.014–5.21), calcitonin:17 (0–150 ng/mL), sedimentation:6 (0–15 mm/h). There were no significant symptoms of acute or chronic thyroiditis. The cause for discordant uptake in the thyroid gland with T1-201 and Tc-99m MIBI scan could not be provided through clinical or laboratory examinations. Parathyroid scan is a noninvasive method used in determining parathyroid adenoma, and Tc-99m MIBI and Tl-201/TcPO−4 subtraction methods are commonly applied [1–3]. The thyroid gland was not visualized on Tc-99m MIBI scintigraphy of suppressed thyroid tissue in a study by Turkolmez et al. [4]. It should be taken into account that sometimes we may not be able to visualize a normal thyroid gland, and in these cases we might encounter suboptimal visualization in T1-201 subtraction method as well. Erdil et al. found that Tl-201 is superior to Tc-99m MIBI in the visualization of suppressed thyroid tissue with a toxic thyroid nodule [5]. Kiratli et al. mentioned decreased uptake of Tc-99m MIBI in the thyroid gland in hemodialysis patients. However, no patient presented an absence of Tc-99m MIBI uptake in the thyroid gland with secondary hyperthyroidism [6]. In this case, the thyroid was not suppressed and the TcPO−4 scan thyroid gland was normal, but the thyroid gland was not visualized with Tc-99m MIBI parathyroid scan, and Tl-201 accumulation in the thyroid gland was not sufficient. To the best of our knowledge, from a search of the published literature, there has been no case like this previously reported. Fig. 1 Scintigraphy of a 21-year-old male with high blood levels of intact parathormone and osteoporosis. a Tc-99m pertechnetate (TcPO−4) pinhole scintigraphy shows bilateral accumulated radioactivity in the thyroid gland. b Thyroid gland is not visualized ...

11. Chronic parathyroiditis in a parathyroid adenoma: a frozen section challenge

Parathyroid adenoma is the most common cause of primary hyper-parathyroidism. Autoimmune thyroiditis occurring together with parathyroid adenoma is well documented, however few cases of chronic parathyroiditis, coexisiting with parathyroid adenoma and autoimmune thyroiditis, have been reported. We present a case of parathyroid adenoma with chronic parathy-roiditis, presenting for frozen section diagnosis, in a patient with hyperparathyroidism and autoimmune thyroiditis. The patient was a 54-year-old man presenting with a 6 month history of fatigue and lethargy. Investigation revealed serum hyper-calcaemia together with hyperparathyroidism. Thyroid function tests noted a mild increase in thyroid hormones, together with elevated thyroid antibodies. The patient underwent imaging with a parathyroid isotope scan, identifying a focal area of increased uptake consistent with an adenoma. A parathyroidectomy was performed with intraoperative frozen section diagnosis. Two specimens were received for frozen section. The frozen section was challenging as both showed glands admixed with lymphoid cells. No atypical nuclear features were noted. Further details obtained during frozen section revealed a history of thyroiditis. The presumptive diagnosis was possible thyroid inclusions in a lymph node or Hashimoto's thyroiditis. A definitive diagnosis was deferred. Paraffin sections revealed encapsulated glandular tissue with features consistent with a parathyroid adenoma. There was a moderately dense lymphoid infiltrate with lymphoid follicles showing germinal centres. Immunohistochemistry confirmed parathyroid tissue. The fi-nal diagnosis was parathyroid adenoma with chronic parathyroiditis. This case presents a possible pitfall particularly on frozen section. While microscopic examination of parathyroid adenomas often reveals scattered lymphocytes, a lymphoid infiltrate with lymphoid follicles is rarely seen. It is important to consider chronic parathy-roiditis as a differential in the setting of a parathyroid adenoma and autoimmune thyroiditis.

Acute Pancreatitis as the First Manifestation of Parathyroid Adenoma

Acute pancreatitis as a first manifestation of primary hyperparathyroidism (PHPT) caused by parathyroid adenoma is exceptionally rare. A 21 year old man presented with severe abdominal pain, nausea and vomiting. Laboratory studies revealed leukocytosis of 15.3 thousand/ ? L, hemoglobin 14.4 g/dL, creatinine 1.31 mg/dL, amylase 1,148 IU/L, lipase 862 IU/L. Serum calcium level was 14.6 mg/dL, intact parathyroid hormone (iPTH) level was 629.6 pg/mL. Neck ultrasound showed a 1.5 × 1 × 1.1 cm solid mass at the posterior inferior aspect of the right thyroid lobe. Parathyroid scan showed a focal area of activity in the right lower lobe suggesting a parathyroid adenoma. The patient underwent parathyroidectomy and pathological examination of the parathyroid gland confirmed a parathyroid adenoma. Although the actual causal relationship between hypercalcemia and pancreatitis has been a persistent topic of debate, detection of hypercalcemia may be a clue to diagnose PHPT due to parathyroid adenoma. After aggressive medical management of acute pancreatitis, parathyroidectomy may improve clinical outcome and prevent further recurrences of pancreatitis. doi: http://dx.doi.org/10.4021/jem114w

Tc-99m sestamibi parathyroid gland scintigraphy: added value of Tc-99m pertechnetate thyroid imaging for increasing interpretation confidence and avoiding additional testing

PurposeTo evaluate the benefit of adding a pertechnetate parathyroid scan (dual-isotope imaging) in the interpretation of sestamibi dual-phase parathyroid scintigraphy. Material and methodsOne hundred and sixteen dual Tc-99m sestamibi (MIBI) and Tc-99m pertechnetate subtraction parathyroid studies, performed between January 2000 and February 2006, were retrospectively reviewed. Dual-phase technetium sestamibi examinations were initially interpreted, with blinding to the technetium pertechnetate findings. Subsequently, technetium pertechnetate scan findings were added, and changes in interpretation were recorded. ResultsBy adding Tc-99m pertechnetate imaging, the interpretation of 17 scans (17/116=14.6%) was substantially altered. This included 5 scans (4%) that changed from negative to positive and 9 scans (8%) that changed from equivocal to positive, excluding ectopic tissue and directing minimally invasive surgery, without the need for further imaging, such as ultrasound, in 12% of cases. One examination changed from positive to negative. In addition, 2 scans changed from equivocal to negative, necessitating further preoperative imaging for the evaluation of additional pathology such as thyroid nodules and lymph nodes and the consideration of hyperplasia. Among the remaining 99 patients, Tc-99m pertechnetate scans may also have contributed to the diagnosis in the 66 positive Tc-99m MIBI scans by increasing confidence in the interpretation and obviating additional imaging. Ten cases remained equivocal. ConclusionBy adding Tc-99m pertechnetate imaging, scan interpretation was changed in 14.6% of cases, and interpretation confidence was enhanced in all but 10 remaining equivocal cases. The addition of a dual-isotope subtraction also eliminated the need for additional testing, such as ultrasound, in 12% of our cases. Increased confidence in interpretation that comes with dual-isotope subtraction may come at the cost of slight lengthening of imaging time but likely simplifies preoperative localization and decreases intraoperative time for many patients with primary hyperparathyroidism.

Intérêt de la scintigraphie parathyroïdienne de soustraction dans la prise en charge de l’hyperparathyroïdie secondaire. À propos de 33 cas

Aim99mTc-Sestamibi is used in the imaging of hyperparathyroidism in order to guide the surgical procedure and to propose methods of less invasive surgery. The aim of our study was to evaluate the efficiency of preoperative subtraction parathyroid scintigraphy (Sestamibi-99mTc/Pertechnetate) in the management of secondary hyperparathyroidism. Patients and methodsThe records of 33 patients with renal impairment consecutively operated from 2009 to 2011 for secondary hyperparathyroidism were retrospectively reviewed. We collected data on parathyroid function, results of parathyroid scintigraphy, intraoperative findings and pathological findings. ResultsScintigraphy was positive in 32 patients by disclosing a total of 75 hyperplastic parathyroid glands. The surgical exploration of all parathyroid glands revealed 99 hyperplastic glands confirmed by histological analysis. The sensitivity of parathyroid scintigraphy was 70.7% with a specificity of 85%. Positive predictive value was 93.3%, while negative predictive value was 50%. No correlation was found between the values of parathyroid hormone (PTH) and calcemia measured preoperatively and scintigraphic results. Discussion and conclusionIn our study, the correlation of scintigraphic data with PTH and serum calcium is not statistically significant. However, owing to a high positive predictive value, the parathyroid scan should be indicated. Value of parathyroid scintigraphy extends to searching ectopic or supernumerary glands and especially in cases of persistent or recurrent hyperparathyroidism.

An Uncommon Cause of Asymptomatic Primary Hyperparathyroidism

Asymptomatic hyperparathyroidism developed in a 65-yr-old man with a history of metastatic papillary thyroid carcinoma. Pertinent laboratory values were: calcium, 10.8 mg/dl (2.70 mmol/liter) [reference range, 8.9– 10.1 mg/dl (2.22–2.52 mmol/liter)]; intact PTH, 135.1 pg/ml (14.3 pmol/liter) [15–50 pg/ml (1.6–5.3 pmol/liter)]; and albumin, 4.5 g/dl (45 g/liter) [3.5–5.0 g/dl (35–50 g/liter)]. Phosphorus, creatinine, and 25-hydroxyvitamin D levels were within normal limits. Thyroid ultrasound for follow-up of his thyroid cancer revealed a 3.0 1.3 0.7-cm cystic mass in the left thyroid bed (Fig. 1A). Twenty-five milliliters of clear fluid were removed from the cyst, revealing an intact PTH of 821 pg/ml (87.1 pmol/liter). Serum calcium was 9.0 mg/dl (2.25 mmol/liter) at 6 months and 9.1 mg/dl (2.27 mmol/liter) at 24 months, with intact PTH 56.5 pg/ml (6 ng/liter) and reduction of the cyst to 0.7 0.6 0.7 cm (Fig. 1B). Parathyroid cysts are rare. An uncommon cause of primary hyperparathyroidism is a functional parathyroid cyst (1). Few parathyroid cysts (10–15%) are functional (presenting with hyperparathyroidism) (2). Functional cysts are treated with surgical excision (3, 4), although successful treatment with aspiration has been described in one case report (3). They mimic thyroid and thymic cysts, thus presenting a diagnostic challenge (4). The presence of elevated intact PTH in aspirated fluid is diagnostic. Parathyroid cysts have absent uptake on radioiodine thyroid scans and rarely are positive on sestamibi parathyroid scans (5). Ultrasound, computed tomography, and magnetic resonance imaging show a cystic cervical or mediastinal mass (5). Aspiration of a functioning parathyroid cyst can be both diagnostic and therapeutic. Acknowledgments

Supernumerary parathyroid glands in hyperparathyroidism associated with multiple endocrine neoplasia type 1

To evaluate frequency, anatomic presentation, and quantities of supernumerary parathyroids glands in patients with primary hyperparathyroidism (HPT1) associated with multiple endocrine neoplasia type 1 (MEN1), as well as the importance of thymectomy, and the benefits of localizing examinations for those glands. Forty-one patients with hyperparathyroidism associated with MEN1 who underwent parathyroidectomy between 1997 and 2007 were retrospectively studied. The location and number of supernumerary parathyroids were reviewed, as well as whether cervical ultrasound and parathyroid SESTAMIBI scan (MIBI) were useful diagnostic tools. In five patients (12.2%) a supernumerary gland was identified. In three of these cases (40%), the glands were near the thyroid gland and were found during the procedure. None of the imaging examinations were able to detect supernumerary parathyroids. In one case, only the pathologic examination could find a microscopic fifth gland in the thymus. In the last case, the supernumerary gland was resected through a sternotomy after a recurrence of hyperparathyroidism, ten years after the initial four-gland parathyroidectomy without thymectomy. MIBI was capable of detecting this gland, but only in the recurrent setting. Cervical ultrasound did not detect any supernumerary glands. The frequency of supernumerary parathyroid gland in the HPT1/MEN1 patients studied (12.2%) was significant. Surgeons should be aware of the need to search for supernumerary glands during neck exploration, besides the thymus. Imaging examinations were not useful in the pre-surgical location of these glands, and one case presented a recurrence of hyperparathyroidism.

Supernumerary parathyroid glands in hyperparathyroidism associated with multiple endocrine neoplasia type 1

To evaluate frequency, anatomic presentation, and quantities of supernumerary parathyroids glands in patients with primary hyperparathyroidism (HPT1) associated with multiple endocrine neoplasia type 1 (MEN1), as well as the importance of thymectomy, and the benefits of localizing examinations for those glands. Forty-one patients with hyperparathyroidism associated with MEN1 who underwent parathyroidectomy between 1997 and 2007 were retrospectively studied. The location and number of supernumerary parathyroids were reviewed, as well as whether cervical ultrasound and parathyroid SESTAMIBI scan (MIBI) were useful diagnostic tools. In five patients (12.2%) a supernumerary gland was identified. In three of these cases (40%), the glands were near the thyroid gland and were found during the procedure. None of the imaging examinations were able to detect supernumerary parathyroids. In one case, only the pathologic examination could find a microscopic fifth gland in the thymus. In the last case, the supernumerary gland was resected through a sternotomy after a recurrence of hyperparathyroidism, ten years after the initial four-gland parathyroidectomy without thymectomy. MIBI was capable of detecting this gland, but only in the recurrent setting. Cervical ultrasound did not detect any supernumerary glands. The frequency of supernumerary parathyroid gland in the HPT1/MEN1 patients studied (12.2%) was significant. Surgeons should be aware of the need to search for supernumerary glands during neck exploration, besides the thymus. Imaging examinations were not useful in the pre-surgical location of these glands, and one case presented a recurrence of hyperparathyroidism.

Primary Hyperaparathyroidism due to Cystic Parathyroid Adenoma not Detected on99mTc-Sestamibi Scan

99m Tc-sestamibi) parathyroid scan is a sensitive diagnostic tool for the localization, although it sometimes shows a false-negative result. Here we report a case of presumed cystic parathyroid adenoma based on clinical findings and analysis of cystic fluid with negative findings in a parathyroid scan. A 44-year-old male patient visited the hospital due to leg pain and compressive symptoms (dysphagia, hoarseness) that had started 4-5 months before. His serum calcium level was 14.4 mg/dL and his intact parathyroid hormone (iPTH) had increased to 478.1 pg/mL. On neck computed tomography, a cystic nodule measuring 6.2 cm was detected in the inferior part of the right thyroid gland. Sestamibi uptake for this nodule was not detected on 2-h delayed imaging, and fluorodeoxyglucose positron emission tomography showed only subtle uptake. Fine-needle as piration was performed and intracystic iPTH had increased to 61,600 pg/mL. Focused parathyroidectomy guided by intraoperative iPTH monitoring led to successful enucleation of the right inferior parathyroid gland. A parathyroid adenoma was confirmed, and his laboratory results had normalized. This study shows that cystic parathyroid adenoma can sometimes be difficult to detect on a 99m Tc-sestamibi parathyroid scan. (Endocrinol Metab 27:83-88, 2012)

Primary Hyperparathyroidism: 11-Year Experience in a Single Institute in Thailand

Primary hyperparathyroidism (PHPT) is not an uncommon disease in the western countries. In Thailand, on the contrary, PHPT was a rare condition with various clinical presentations. All 45 PHPT patients who underwent parathyroidectomy at the Department of Surgery, Siriraj Hospital during January 1997 and December 2007 were retrospectively reviewed. Demographic data, clinical presentation, localizations imaging, operative procedures, findings, complications, and pathological reports were analyzed. Median age was 49 years (range 15–89 years) with female: male ratio of 3 : 1. Only one patient (2.2%) was asymptomatic PHPT. Of all symptomatic cases, 30 (66.7%) had skeletal symptoms, 7 (15.6%) had renal impairment, and 39 (86.7%) had mixed symptoms. 42 patients (93.3%) had parathyroid scan and all had bilateral exploration of the neck. Postoperative hungry bone syndrome was noted in 10 patients (22%). On followup, skeletal and neuropsychiatric symptoms were improved but the renal impairment was remained. The s small number of asymptomatic PHPT in our study may refer to large number of underdiagnosed PHPT in general population. The guideline for screening serum calcium for diagnosis of PHPT in Thai populations will improve the long-term consequence of the disease but will need further information to identify the target group.

A Case of Parathyroid Carcinoma in a Patient with Stage 3 Chronic Kidney Disease

Parathyroid carcinoma is a rare disease in patients with primary hyperparathyroidism. We experienced a case of parathyroid carcinoma presenting with hyperparathyroidism. A 62-year-old male patient had hypercalcemia, chronic kidney disease, and an elevated parathyroid hormone level for at least 3 months. An ultrasonogram and parathyroid scan did not show parathyroid neoplasm. He underwent left hemithyroidectomy and parathyroidectomy. Biopsy revealed a parathyroid carcinoma. His azotemia and hypercalcemia improved after surgery. (Korean J Med 2012;83:796-801)

Giant cystic parathyroid adenoma with thrombosis of internal jugular vein seen on CT and Tc-99m methoxy isobutyl isonitrile parathyroid scan

Primary hyper-parathyroidism is attributed by a solitary parathyroid adenoma in 80-85% cases and mostly are non-palpable and needs imaging for localization. Cystic degeneration of parathyroid adenoma is rarely seen in primary hyperparathyroidism. We are presenting a case of giant cystic functioning parathyroid adenoma with associated localized co-morbids.