From the Guidelines
The primary treatment for parathyroid adenoma is surgical removal through parathyroidectomy, specifically minimally invasive parathyroidectomy (MIP), which is considered curative in most cases, as it offers the benefits of shorter operating times, faster recovery, and decreased perioperative costs 1.
Treatment Overview
The treatment of parathyroid adenoma involves surgical excision of the abnormally functioning parathyroid tissue, which is typically indicated even in asymptomatic cases, due to the potential negative effects of long-term hypercalcemia 1. There are two accepted curative operative strategies for primary hyperparathyroidism (PHPT): bilateral neck exploration (BNE) and MIP. MIP is defined as a unilateral operation utilizing limited dissection for targeted removal of only the affected gland, and it requires confident and precise preoperative localization of a single parathyroid adenoma to guide the surgical approach.
Preoperative Considerations
Before surgery, patients should have their calcium and vitamin D levels optimized. Preoperative localization studies, such as sestamibi scan and ultrasound, are essential to identify the single adenoma and guide the surgical approach 1. Intraoperative PTH monitoring is used to confirm removal of the hyperfunctioning gland.
Postoperative Care
Postoperatively, patients may require calcium supplementation to prevent hypocalcemia as the remaining normal parathyroid glands resume function, which can take several days to weeks. Patients should be monitored for "hungry bone syndrome," a condition where rapid bone remineralization after surgery causes severe hypocalcemia, requiring more aggressive calcium and vitamin D supplementation.
Alternative Treatments
For patients who are poor surgical candidates, medical management options include cinacalcet to reduce parathyroid hormone secretion, bisphosphonates for bone protection, and adequate hydration with avoidance of thiazide diuretics. Ethanol ablation or radiofrequency ablation may be considered as minimally invasive alternatives in select cases.
Rationale for Treatment
The rationale for surgical treatment is that parathyroid adenomas autonomously secrete excess parathyroid hormone, causing hypercalcemia and its associated complications, including osteoporosis, kidney stones, and neuropsychiatric symptoms, which typically resolve after adenoma removal 1.
From the FDA Drug Label
Seventeen patients with severe hypercalcemia due to primary HPT, who had failed or had contraindications to parathyroidectomy, participated in an open-label, single-arm study. Sixty-seven patients with primary HPT who met criteria for parathyroidectomy on the basis of corrected total serum calcium (> 11.3 mg/dL [2.82 mmol/L] and ≤ 12.5 mg/dL [3. 12 mmol/L]), but who were unable to undergo parathyroidectomy participated in a randomized, double-blind, placebo-controlled study.
The treatment of parathyroid adenoma with cinacalcet is supported by the FDA drug label.
- Key points:
- Cinacalcet can be used to treat patients with primary hyperparathyroidism (HPT) who are unable to undergo parathyroidectomy.
- The medication can help reduce serum calcium levels in these patients.
- The study results show that cinacalcet-treated patients achieved a significantly higher percentage of mean corrected total serum calcium concentration within the normal range compared to placebo-treated patients 2.
- Dosage: The dose of cinacalcet can be titrated to maintain a corrected total serum calcium concentration within the normal range, with a median dose of 60 mg/day at the completion of the study.
From the Research
Treatment Options for Parathyroid Adenoma
- Surgical treatment: Parathyroidectomy is the standard of care for primary hyperparathyroidism, with a high success rate of 95-99% and a low complication rate 3, 4.
- Non-surgical treatment: Radiofrequency ablation (RFA) of parathyroid adenomas is a viable alternative to parathyroidectomy in patients who do not meet the criteria for surgery or do not wish to undergo surgery 5.
- Medical management: Antiresorptive drugs (bisphosphonates, oestrogens, and selective oestrogen receptor modulators) and inhibitors of PTH secretion (calcimimetics) can be used for symptomatic control of primary hyperparathyroidism 4, 6.
- Other non-surgical ablative techniques: Selective percutaneous ethanol injection and transcatheter ablation of pathological parathyroid tissue may be adequate in cases where surgery is contraindicated 4.
Indications for Treatment
- Symptomatic primary hyperparathyroidism: Surgery is indicated for all patients with symptomatic primary hyperparathyroidism 3.
- Asymptomatic primary hyperparathyroidism: Asymptomatic individuals should be surgically treated when they are younger than 50 years, have severe hypercalcemia, markedly reduced creatinine clearance, and/or profound osteopenia 3.
- Severe hypercalcemia: Severe hypercalcemia must be swiftly and thoroughly assessed to prevent hypercalcemic crisis, and excision of the parathyroid adenoma is the treatment of choice 7.