Dr. YC Pang Department of Surgery United Christian Hospital

Dr. YC PangDepartment of Surgery

United Christian Hospital

.. It seems hardly credible that the loss of bodies so tiny as the parathyroids should be follow by a result so disastrous.

William S. Halsted, 1907Halsted WS. Hypoparathyreosis, status parathyreoprivus, and transplantation of the parathyroid glands. Am J Med Sci 1907;134:1–12.

Primary hyperparathyroidism (pHPT) - a common endocrine disorder

Classical manifestations - stones, bones, groans and moans

Asymptomatic primary hyperparathyroidism- increasingly diagnosed due to routine biochemical testing

Bilateral cervical exploration

Focused parathyroidectomy

localized by preoperative sestamibi scan or US

A central or lateral incision measuring from 2 to 4 cm over the targeted lesion

Only the abnormal parathyroid gland is identified and excised

• Improved cosmetic results with smaller incisions

• Decreased pain, shorter operative time• Ambulatory surgery• Rapid postoperative recovery• Less injury to the recurrent laryngeal nerve• Decreased postoperative hypocalcaemia• Comparable success rates to conventional

BNE

• Symptomatic - Clear indication for surgical treatment• Asymptomatic- Serum calcium level 1.0 mg/dL (0.25mmol/L) or greater

than the accepted normal range- 24-h urinary calcium excretion greater than 400 mg/day- Creatinine clearance reduced by 30%- T-score less than –2.5 at any site- age younger than 50 years

NIH guidelinesBilezikian JP, Potts JT Jr, Fuleihan Gel H, et al. Summary statement from a workshop on asymptomatic primary hyperparathyroidism: a perspective for the 21st century. J Clin Endocrinol Metab 2002;87(12):5353–61

• Many experience surgeons basing the operative decision not only on these objective criteria but on subjective complaints as well

• Several studies showing improvements of depression, anxiety, sleep disturbances, poor memory, and cognitive impairment after parathyroidectomy

Kouvaraki MA, Greer M, Sharma S, et al. Indications for operative intervention in patients with asymptomatic primary hyperparathyroidism: practice patterns of endocrine surgery. Surgery 2006;139:527–34Pasieka JL, Parsons LL. Prospective surgical outcome study of relief of symptoms following surgery in patients with primary hyperparathyroidism. World JSurg 1998;22(6):513–9

Recent evidence from a long-term study of primary hyperparathyroidism over 15 years suggests the NIH guidelines for parathyroidectomy do not reliably predict worsening disease progression in asymptomatic patients

Rubin MR, Bilezikian JP, McMahon DJ, et al. The natural history of primary hyperparathyroidism with or without parathyroid surgery after 15 years. J Clin Endocrinol Metab 2008;93(9):3462–70

Most of them present with vague/non-specific symptoms

<5% truly asymptomatic Evidence of improvement in objective

and subjective parameters Evolution of parathyroid surgery Pro-active approach should be adopted

The only localization that a patient needs who has primary hyperparathyroidism is the localization of an experienced surgeon!

—John L. Doppmann, 1991

Brennan MF. Lessons learned. Ann Surg Oncol 2006;13(10):1322–8

Sestamibi scintigraphy Ultrasound Sestamibi + SPECT Combined Mibi and USG CT/MRI

Able to localize 80% to 90% of single abnormal parathyroid glands

Less sensitive in the diagnosis of multiglandular disease (MGD)

False positive: thyroid nodule, lymph node

False negative: small parathyroid lesion, suboptimal dose

Carniero-Pla DM, Solorzano CC, Irvin GL. Consequences of targeted parathyroidectomy guide by localizing studies without intraoperative parathyroid hormone monitoring. J Am Coll Surg 2006;202:715–22

Commonly used for preoperative parathyroid localization

Delineating an enlarged parathyroid gland from surrounding structures

70-80% accuracy

Berri RN, Lloyd LR. Detection of parathyroid adenoma in patients with primary hyperparathyroidism: the use of office-based ultrasound in preoperative localization. Am J Surg 2006;191:311–4

Obtain real-time information regarding the anatomical location of enlarged parathyroid glands among several other structures

Allows for evaluation of thyroid abnormalities that may require surgical treatment

Particularly useful in detecting smaller parathyroid lesions that may reside posterior to thyroid gland, at retroesophagus or within mediastinum

Yip L, Pryma DA, Yim JH, et al. Can a lightbulb sestamibi SPECT accurately predict single-gland disease in sporadic primary hyperparathyroidism. World J Surg 2008;32(5):784–92

Increase accuracy of localization of a single adenoma from 94% to 99%

Operative success rate approach 99% when result concordant, obviating the need for Intraoperative PTH monitoring (IPM)

Concordant only 50% to 60% of the timeMihai R, Palazzo FF, Gleeson FV, et al. Minimally invasive parathyroidectomy without intraoperative parathyroid hormone monitoring in patients with primary hyperparathyroidism. Br J Surg 2007;94:42–7

Intact PTH has short half-life (2-4 minutes)

Normal parathyroid glands in patients with hyperparathyroidism are suppressed by hypercalcemia

The changes in PTH detected by the rapid PTH assay preoperative, preexcision, and postexcision is able to confirm or refute biochemical cure

A decrease of intact PTH levels greater than 50% from the highest value in 10 minutes after removal of all abnormal parathyroid tissue

Operative success with predictive cure in 97% of casesCarneiro DM, Solorzano CC, Nader MC, et al. Comparison of intraoperative iPTH assay (QPTH) criteria in guiding parathyroidectomy: which criterion is the most accurate? Surgery 2003;134(6):973–81

Aspirate of parathyroid tissue diluted in a syringe containing 1 mL saline

Rapid assay yields PTH values greater than 1500 pg/mL confirm diagnosis

Increase by 10% at initial operation Increase by 18% in reoperative patients

for failed parathyroidectomy

Chen H, Pruhs Z, Starling JR, et al. Intraoperative parathyroid hormone testing improves cure rates in patients undergoing minimally invasive parathyroidectomy. Surgery 2005;138(4):583–90Irvin GL, Molinari AS, Figueroa C, et al. Improved success rate in reoperative parathyroidectomy with intraoperative PTH assay. Ann Surg 1999;229(6):874–9

• MIBI alone- multiple case series and a single retrospective comparative study recommend the use of IPM

• Concordant MIBI and USG- add little if any benefit to the rate of cure

• Discordant scans- IPM recommendedIntraoperative adjuncts in surgery for primary hyperparathyroidismBarney J. Harrison & Frederic TriponezLangenbecks Arch Surg (2009) 394:799–809

Focused approach parathyroidectomy without intraoperative PTH monitoring is a safe and effective

treatment for primary hyperparathyroidism

Dr. YC Pang, Dr. KP Tsui, Dr. CY Choi, Dr. TL Chow, Dr. SH LamDepartment of Surgery

United Christian Hospital

Focused parathyroidectomy Primary hyperparathyroidism Jan 2002 – June 2009

82 patients - primary hyperparathyroidism 76(92.7%) - focused approach

parathyroidectomy Mean age 60.3 (21-88) M:F 19:57 Mean pre-operative serum calcium: 2.8

mmol/L Mean pre-op PTH : 69.84 pmol/L

USG (Surgeon)

MIBI CT/MRI

Successful localization

67 55 4

Failed localization 9 17 7

Not done 0 4 65

Total 76 76 76

Ultrasound MIBI Total

Failed localization/ not done

Able to localize

Failed localization 2 7 9

Able to localize 19 48 67

Total 21 55 76

Sensitivity of USG 67/76 (88.2%) Sensitivity of MIBI 55/72 (76.4%) Combined USG + MIBI 74/76 (97.4%) 2 failed localization by USG/MIBI

Localized by CT scan

76 (92.7%) focused approach parathyroidectomy

49 (64.5%) LA 27 (35.5%) GA Mean operating time 61.2 minutes Use of IPM: 4 patients (5.3%)

• 70 (97.2%) operative success• No persistent hypoparathyroidism• 3 patients (3.9%) suffered from hungry

bone syndrome requiring prolonged calcium supplement

• 4 patients (5.3%) transient RLN palsy• 2 patients (2.6%) permanent RLN palsy

Only 4 patients All of them had > 50% reduction in PTH

10mins after excision 100% operative success No recurrence No hypocalcemia No RLN palsy

Focused parathyroidectomy is the well adopted treatment for most of the cases

Combined USG and MIBI scan increases accuracy of localization

Intraoperative PTH monitor is recommended in case of discordant scan to improve the operative success

Resources govern the choice of pre-operative localization method, or intraoperative adjuncts

In properly selected case, focused parathyroidectomy without routine use of IPM is safe and effective treatment