Indications for Parathyroidectomy
Parathyroidectomy should be recommended for patients with severe hyperparathyroidism (persistent serum levels of intact PTH >800 pg/mL), associated with hypercalcemia and/or hyperphosphatemia that are refractory to medical therapy. 1
Primary Hyperparathyroidism (PHPT)
- Parathyroidectomy is indicated for all symptomatic patients with PHPT 2
- Surgery should be considered for most asymptomatic patients with PHPT as it is more cost-effective than observation or pharmacologic therapy 2
- In countries with routine biochemical screening (US, Canada, Europe), PHPT often presents as asymptomatic, but surgical treatment is typically indicated even when asymptomatic due to potential negative effects of long-term hypercalcemia 1
- Surgical excision is the only established curative treatment for PHPT 3
Secondary Hyperparathyroidism (SHPT)
- Parathyroidectomy is indicated when severe hyperparathyroidism (persistent serum intact PTH >800 pg/mL) occurs with hypercalcemia and/or hyperphosphatemia that does not respond to medical therapy 1
- Surgical intervention should be considered when medical therapy fails despite optimal management with dietary phosphate restriction, phosphate binders, and vitamin D sterols 4
- Calciphylaxis with elevated PTH levels (>500 pg/mL) warrants surgical intervention as clinical improvement has been documented after parathyroidectomy 4
- Patients with chronic kidney disease who have dialysis for over 10 years have a 10% likelihood of requiring parathyroidectomy, increasing to 30% after more than 20 years 1
Tertiary Hyperparathyroidism
- Surgical intervention should be considered when persistent hypercalcemia occurs post-renal transplant (particularly if serum calcium is ≥11.5 mg/dL) 4
- Tertiary hyperparathyroidism occurs in patients with long-standing secondary hyperparathyroidism and is characterized by lack of PTH suppression despite rising serum calcium levels 1
Surgical Approaches
Both subtotal parathyroidectomy and total parathyroidectomy with parathyroid tissue autotransplantation are effective surgical options 1
For primary hyperparathyroidism:
- Bilateral neck exploration (BNE) is the traditional approach and remains necessary in cases of discordant or non-localizing preoperative imaging or when there is high suspicion for multigland disease 1
- Minimally invasive parathyroidectomy (MIP) is often performed for single adenomas as it offers shorter operating times, faster recovery, and decreased perioperative costs 1
For secondary hyperparathyroidism:
Pre-operative Imaging
- Preoperative imaging is essential for reoperative parathyroid surgery 1
- Imaging with 99Tc-Sestamibi scan, ultrasound, CT scan, or MRI should be performed prior to re-exploration parathyroid surgery 1
- For primary hyperparathyroidism requiring minimally invasive parathyroidectomy, confident and precise preoperative localization of a single parathyroid adenoma is necessary 1
Post-operative Management
- Monitor ionized calcium every 4-6 hours for the first 48-72 hours after surgery, then twice daily until stable 1
- If blood levels of ionized calcium fall below normal (<0.9 mmol/L), initiate calcium gluconate infusion at a rate of 1-2 mg elemental calcium per kg body weight per hour 1
- When oral intake is possible, provide calcium carbonate 1-2 g three times daily and calcitriol up to 2g/day 1
- Adjust or discontinue pre-surgery phosphate binders as needed based on serum phosphorus levels 1
Important Considerations and Pitfalls
- Despite clear guidelines, studies show that parathyroidectomy is underutilized in both symptomatic and asymptomatic patients who meet criteria for surgery 5
- High-volume surgeons have better outcomes for parathyroidectomy 2
- Preoperative parathyroid biopsy should be avoided 2
- The possibility of multigland disease should be routinely considered 2
- For minimally invasive parathyroidectomy, intraoperative parathyroid hormone monitoring via a reliable protocol is recommended 2
- Devascularized normal parathyroid tissue should be autotransplanted 2