Primary hyperparathyroidism. Low surgical morbidity supports liberal attitude to operation

Risk Assessment for Severe Postoperative Hypocalcaemia after Neck Exploration for Primary Hyperparathyroidism

Background and Aims:

A further development of the risk profile for severe postoperative hypocalcaemia after surgery for primary hyperparathyroidism (pHPT) was made with the aim of expanding the group of patients who can be discharged safely after 23 hours.

Methods:

Prospective study with 156 consecutive pHPT patients (158 operations) during 2001 and 2002. Risk factors for postoperative severe hypocalcaemia (ionised calcium <1 mmol/L), were (1) preoperative concentration of parathyroid hormone (PTH) > 35 pmol/L (five times the upper reference value, reference range 1.1 to 6.9), (2) history of previous neck surgery, (3) biopsy/excision of > 2 parathyroid glands or (4) concomitant thyroid surgery.

Results:

The risk factors showed a sensitivity of 100 % (9/9). In 110 of the operations (70%) no risk factors were identified. Postoperative calcium levels were significantly lower after 48 operations with risk factor(s) identified, as compared to the group without risk factors (p < 0.01). Seven of 17 patients (41%) with PTH > 35 pmol/L developed severe postoperative hypocalcaemia. Two of 31 patients (6%) with PTH < 35 pmol/L in the presence of other risk factor(s) developed severe postoperative hypocalcaemia.

Conclusion:

Patients with no risk factor can safely been discharged from hospital on the first postoperative day. Patients with preoperative concentration of PTH > 35 pmol/L (five times the upper reference value) should stay in hospital until nadir level of calcium is reached. Patients with concentration of parathyroid hormone less than 35 pmol/L in the presence of other risk factor(s) may have an early discharge from hospital (second postoperative day) combined with outpatient measurements of calcium levels.

Role of preoperative intact parathyroid hormone levels in predicting the likelihood of multiglandular disease in primary hyperparathyroidism

BACKGROUND

Minimally invasive parathyroidectomy has become increasingly popular for the treatment of primary hyperparathyroidism, but is not a feasible option for multiglandular disease. It has been suggested that preoperative intact parathyroid hormone (iPTH) levels may predict multiglandular disease. We examined this hypothesis in patients who underwent surgical intervention for primary hyperparathyroidism at Johns Hopkins Medical Institutions.

METHODS

We retrospectively reviewed 502 consecutive patients with primary hyperparathyroidism who underwent parathyroidectomy. Multivariable logistic regression analysis assessed preoperative iPTH levels as a predictor of multiglandular disease and a positive sestamibi scan, after adjustment for age, sex, and race.

RESULTS

Preoperative iPTH levels were not significantly associated with a greater likelihood of multiglandular disease. However, sestamibi scan positivity was significantly more likely in patients with higher preoperative iPTH levels.

CONCLUSION

Preoperative iPTH levels are not helpful in predicting multiglandular disease and should not be used to exclude a minimally invasive parathyroidecotomy for patients with primary hyperparathyroidism. © 2010 Wiley Periodicals, Inc. Head Neck, 2011.

Operation for primary hyperparathyroidism: the new versus the old order. A randomised controlled trial of preoperative localisation

BACKGROUND AND AIMS

In patients with primary hyperparathyroidism (PHPT), parathyroid imaging is nowadays routinely used for the purpose to perform a focused unilateral minimally invasive operation. The outcome of this new strategy has, however, not been established in randomised trials.

MATERIAL AND METHODS

Patients were randomised to either preoperative localisation with sestamibi scintigraphy and ultrasonography (group I) or no preoperative localisation (group II). In group I, a minimally invasive parathyroidectomy was performed in patients in whom both localisation studies were consistent with a single pathological gland, whereas a conventional bilateral neck exploration was performed in cases with negative localisation findings. In group II all patients underwent conventional bilateral neck exploration. Primary outcome measure was normocalcaemia at 6 months postoperatively.

RESULTS

In the preoperative localisation group (group I) 23/50 (46%) of the patients could be operated on with the focused operation whereas 26/50 (52%) were operated on by bilateral neck exploration. All patients in the no localisation group (group II; n = 50) were operated on with the intended bilateral neck operation. Normocalcaemia was obtained in 96% and 94% in group I and II, respectively. Total (localisation and operative) costs were 21% higher in group I.

CONCLUSIONS

Routine preoperative localisation, with the intention to perform minimally invasive parathyroidectomy, is not cost effective if concordant results of scintigraphy and ultrasonography are a prerequisite for the focused operation. Less than half of the patients were successfully managed with this strategy, at a higher cost and without obtaining a more favourable clinical outcome.

Asymptomatic primary hyperparathyroidism: a surgical perspective

Since the advent of multichannel autoanalyzers and routine screening of serum calcium levels, prevalence of primary hyperparathyroidism (pHPT) has increased to between 0.1% and 0.4%. As more patients present with "asymptomatic" pHPT, ideal treatment of "mild" disease becomes more controversial, with the possibility of safe, nonoperative management in a selected group of patients. Accumulated evidence confirms that the majority of these patients suffer from vague, nonspecific complaints that are very real and can improve following parathyroidectomy. Furthermore, parathyroidectomy in patients with pHPT has been demonstrated to improve bone mineral density, reduce fracture risk, and improve health-related quality of life and possibly overall survival. Therefore, all patients with primary hyperparathyroidism should be referred for surgical evaluation by an experienced endocrine surgeon.

Primary hyperparathyroidism: renal calcium excretion in patients with and without renal stone sisease before and after parathyroidectomy

The effect of parathyroidectomy on renal calcium excretion per 24 hours in patients with primary hyperparathyroidism with and without a history of renal stone disease was evaluated. Altogether, 91 patients operated on for primary hyperparathyroidism formed the study group for preoperative analysis. Of these patients, 42 were evaluated 1 to 3 years postoperatively. The median preoperative serum calcium level was 2.92 mmol/L, and it was the same for patients with or without renal stones. Preoperatively we found no differences in renal calcium excretion between patients with and without renal stone disease. The median renal calcium excretion was 6.80 mmol/24 hr. At 1 to 3 years after successful parathyroidectomy the group with renal stone disease had higher renal calcium excretion than the group without renal stones (p = 0.03). The reduced effect of parathyroidectomy on renal calcium excretion in the patients with renal stone disease indicates that factors not related to the hyperparathyroid state could contribute to disturbances in renal calcium excretion and hence stone formation. In conclusion, the pathologic basis for renal stone formation in patients with primary hyperparathyroidism might not be the hyperparathyroid state alone; stone formation could be related to other predisposing factors as well. Therefore, although parathyroidectomy can cure hyperparathyroidism, the curative effect on renal stone disease should be reconsidered.

Surgical approaches to primary hyperparathyroidism

Primary hyperparathyroidism, once thought to be a rare disease entity, is now a common problem. It can be diagnosed with nearly 100% accuracy. Surgical therapy is the only definitive cure for this disease, and normocalcemia is achieved in 95% of patients at initial operation when performed by an experienced surgeon. Even when the operation is initially unsuccessful, most of the patients with persistent disease can subsequently be cured. Although some clinicians have proposed that asymptomatic patients can be medically managed, the cost of such treatment, problems with patient compliance with long-term follow-up, the increased risk of premature death associated with primary hyperparathyroidism, and the low morbidity of operation support a liberal policy for exploration in most patients. The authors believe that nonoperative therapy should be limited to older patients with multiple comorbid conditions and minimal hypercalcemia and clinical manifestations.

Profile of a clinical practice: Thresholds for surgery and surgical outcomes for patients with primary hyperparathyroidism: a national survey of endocrine surgeons

A 1991 NIH Consensus Development Conference statement provided recommendations for the management of patients with asymptomatic and minimally symptomatic primary hyperparathyroidism (primary HPT), but adherence to these guidelines has not been documented. We conducted a cross-sectional survey of North American members of the American Association of Endocrine Surgeons inquiring about surgeon and primary HPT patient characteristics, thresholds for surgery, and clinical outcomes. Multivariate regression was used to assess the relationship of physician characteristics to practice patterns and outcomes. Of 190 surgeons surveyed, 147 (77%) responded; 109 provided complete responses (57%). These surgeons spend 66% of their time in patient care and perform an average of 33 (range, 1-130) parathyroidectomies/yr. More than 72% of primary HPT patients who underwent surgery were asymptomatic or minimally symptomatic. High volume surgeons (>50 cases/yr) had significantly lower thresholds for surgery with respect to abnormalities in preoperative creatinine clearance, bone densitometry changes, and levels of intact PTH and urinary calcium compared to their low volume colleagues (1-15 cases/yr). Overall reported surgical cure rates were 95.2% after primary operation and 82.7% after reoperation. Compared to high volume surgeons, low volume endocrine surgeons had significantly higher complication rates after primary operation (1.9% vs. 1.0% respectively; P < 0.01) and reoperation (3.8% vs. 1.5%; P < 0.001) as well as higher in-hospital mortality rates (1.0% vs. 0.04%; P < 0.05). Endocrine surgeons operate on a large number of asymptomatic or minimally symptomatic primary HPT patients. Even among a group of highly experienced surgeons who typically see patients after referral from endocrinologists, clinical outcomes and criteria for surgery vary widely and appear to be associated with surgeon experience. Their criteria for surgery diverge from NIH guidelines. These results implore the endocrine community to examine the evidential basis for decisions made in the management of primary HPT.

Re-operative surgery for recurrent or persistent primary hyperparathyroidism

BACKGROUND

While initial surgery for primary hyperparathyroidism, in experienced hands, will result in a cure in 98% of cases, re-operative surgery remains a significant challenge. Because attitudes as to who should perform initial exploration for hyperparathyroidism are significantly different around the world, the approach to re-operative surgery may also vary. The aim of the present study was to examine a local experience of re-operative surgery for recurrent or persistent primary hyperparathyroidism.

METHODS

Information on indications for surgery, the procedure performed, pathology and complications of all re-operative procedures for primary hyperparathyroidism in the period January 1962 to December 1996 were obtained from a prospective database.

RESULTS

Sixteen patients with persistent (n = 12) or recurrent (n = 4) primary hyperparathyroidism were treated in the unit over the study period. Eight patients had their initial operation within the unit at Royal North Shore Hospital and eight were referred from elsewhere for re-operation. Nine of the 12 patients with persistent hyperparathyroidism were cured by re-operation with failures due to spillage at first operation (n = 1) or failure to find any additional pathology (n = 2). All four patients with recurrent hyperparathyroidism were cured. All the failures occurred early in the learning phase of the unit, with a 100% cure rate for re-operative procedures performed in the last 15 years. The most common finding in patients referred from elsewhere with a failed initial operation was a missed inferior adenoma in association with the thymus. Localization studies had a variable sensitivity, with sestamibi scintigraphy, selective venous sampling and ultrasonography providing the most reliable information.

CONCLUSIONS

Re-operative surgery for persistent or recurrent hyperparathyroidism is an uncommon procedure in Australia when compared to major centres in the USA. Successful surgery depends upon experience and an accurate knowledge of the embryology and anatomy of the parathyroid glands.

Survival after surgical treatment for primary hyperparathyroidism

BACKGROUND

Reports have suggested that patients with primary hyperparathyroidism (pHPT) are at increased risk for premature death, even when they reach normocalcemia. This study addresses factors that may be of relevance for long-term outcome.

METHODS

Between 1980 and 1984, 1052 patients (27% men and 73% women; median age, 59 years) underwent initial cervical exploration for pHPT. Long-term follow-up was obtained with regard to overall survival and cause of death. By using univariate and multivariate (Cox) survival analysis, subgroups of patients were compared.

RESULTS

Median follow-up was 12 years (range, 0 to 15 years). Overall, survival was not decreased compared with the expected survival of a gender- and age-matched midwest population. Survival was better in patients with a history of kidney stones (p = 0.044), without osteoporosis (p = 0.004), and without muscle weakness (p = 0.013).

CONCLUSIONS

Decreased long-term survival was not evident in this study. Age at the time of initial surgical treatment and the degree of endocrine activity of the diseased glands appear to be the most important independent prognostic factors for survival. Comparison of these data to prior Scandinavian data is not justified, principally because of the less advanced stage of disease in this study.

The current role of parathyroid cryopreservation and autotransplantation in parathyroid surgery: an institutional experience

BACKGROUND

Hypoparathyroidism after cervical exploration is a rare but problematic complication. Cryopreservation and subsequent autotransplantation of parathyroid tissue are infrequently used to combat this problem; effective usage of this surgical adjunct remains variable.

METHODS

From 1981 through 1995 we performed 3080 cervical explorations for hyperparathyroidism. Cryopreservation was performed in 112 (3.6%) patients. This review evaluates our indications and usage of cryopreservation and autotransplantation and the eventual outcome after autotransplantation.

RESULTS

Of 81 women and 31 men, 106 (95%) had undergone previous exploration for hyperparathyroidism or thyroid disease. The primary indication for cryopreservation was uncertainty about the viability and number of remaining parathyroid glands. After operation 23 patients (20%) were permanently hypocalcemic and became autotransplantation candidates. Thirteen patients underwent a total of 15 autotransplantations (median postoperative interval, 7 months). Although 6 of 15 grafts (40%) were shown to secrete parathyroid hormone, only three patients (23%) were normocalcemic without supplemental therapy.

CONCLUSIONS

Cryopreservation with autotransplantation is in theory a sound but difficult practice to correct postexploration hypocalcemia. The principal indication for cryopreservation is the uncertainty regarding the status of remaining normal parathyroid tissue. Because we cannot predict postexploration hypocalcemia, cryopreservation plays a small but sometimes integral role in parathyroid surgery. Indications for cryopreservation in our practice are rare, and the rate of cryopreservation tissue usage is low.

Characteristics of patients surgically treated for primary hyperparathyroidism with and without renal stones

BACKGROUND

Between 1980 and 1984, 312 (30%) of 1038 patients undergoing initial cervical exploration for primary hyperparathyroidism (pHPT) at our institution had proven renal stones.

METHODS

In this retrospective study we focused on clinical characteristics, biochemical tests, perioperative and pathologic findings, and immediate outcomes of operation, comparing findings in patients with and without renal stones.

RESULTS

Patients with renal stones were more often younger male patients, had serum phosphorus levels significantly lower (p < 0.02) and 24-hour urinary calcium excretion significantly higher (p < 0.0001) than patients without renal stones, and had a significantly higher (p < 0.05) proportion of abnormal glands weighing less than 250 mg. Relevant diagnostic preoperative variables were evaluated by means of multivariate analysis to determine whether they independently had predictive power with regard to renal stones. Male gender and younger age were significantly associated with the presence of renal stones, providing odds ratios of 2.5 and 1.4, respectively. In addition, the risk of having renal stones was significantly related to minimally elevated serum calcium levels (p < 0.05), serum phosphorus levels (p = 0.02), and 24-hour urine calcium excretion (p < 0.05).

CONCLUSIONS

In patients with renal stones the diagnosis of pHPT should be considered. If the diagnosis is confirmed, a liberal approach to cervical exploration should be taken.

Asymptomatic primary hyperparathyroidism

The prevalence of hypercalcaemia in the adult population is probably between 0.6 and 1.1%, sufferers being predominantly women over 50 years of age. Most apparently asymptomatic hypercalcaemic patients are found to have primary hyperparathyroidism, and may in fact show some symptoms of the condition (lowered bone mineral density, cardiovascular disease and/or neuropsychiatric symptoms). The criteria for surgical intervention in these cases are discussed in the light of the high success rate of parathyroidectomy in experienced hands and the lack of effective alternative treatments.

Long-term health risk of primary hyperparathyroidism: the effect of surgery

Primary hyperparathyroidism is a common disease but 90% of sufferers remain undetected. In elderly women its prevalence is about 1%. The disease can cause severe hypercalcaemia and lead to life-threatening symptoms. However, the majority of cases represent milder forms of hyperparathyroidism with minimal symptoms or no symptoms at all, and slight hypercalcaemia which does not progress during follow-up. Surgery is the only effective treatment of primary hyperparathyroidism and most of the symptoms respond favourably to surgery. Nevertheless, the role of surgery has been controversial in the treatment of mini-symptomatic patients. Recently it has become evident that primary hyperparathyroidism is associated with increased mortality due mainly to cardiovascular diseases, and it has been shown that surgical treatment is able to diminish or even eliminate this risk of premature death. The extra mortality is connected also to the mild and nonprogressive forms of the disease, and it seems to have a strong correlation with the duration of the disease. This aspect favours active treatment at an early stage of the disease. Conservative treatment can be considered only in old patients with mild and stable clinical course. Primary hyperparathyroidism is an important risk factor causing morbidity and mortality.