Heterotopic autotransplantation of parathyroid tissue in children undergoing total thyroidectomy

Children are at a high risk of hypocalcaemia and hypoparathyroidism after total thyroidectomy

PURPOSE

Disruption of calcium homeostasis is the most common complication after total thyroidectomy in adults. We explored the incidence and risk factors of hypocalcaemia and hypoparathyroidism after total thyroidectomy in children (≤18 years of age).

METHODS

One hundred six children underwent total thyroidectomy. Patient, operative and outcome data were collected and analyzed.

RESULTS

The indication for surgery was Graves' disease in 52 children (49.1%), Multiple Endocrine Neoplasia type-2 in 36 (33.9%), multinodular goiter in 3 (2.8%) and follicular/papillary thyroid carcinoma in 15 (14.2%). Neck dissection was performed in 23 children (18.9%). In 14 children (13.2%), autotransplantation was performed; in 31 (29.2%), ≥1 glands were found in the specimen. Hypocalcaemia within 24 h of thyroidectomy was observed in 63 children (59.4%) and 52 (49.3%) were discharged on supplements. Hypoparathyroidism at 6 months persisted in 23 children (21.7%). The ratios of all forms of calcium-related-morbidity were larger among children with less than four parathyroid glands remaining in situ: hypocalcaemia within 24 h of thyroidectomy (54.0% versus 47.5%; p = 0.01), hypoparathyroidism on discharge (64.4% versus 37.7%; p = 0.004) and long-term hypoparathyroidism (31.1% versus 14.8%; p = 0.04).

CONCLUSION

The incidence of postoperative hypocalcaemia and hypoparathyroidism among children undergoing total thyroidectomy is considerable. The inability to preserve the parathyroid glands in situ during surgery seems an important factor. For optimal outcomes, the parathyroid glands should be preserved in situ.

TYPE OF STUDY

Prognosis Study.

LEVEL OF EVIDENCE

Level IV.

Predictors of graft function after parathyroid autotransplantation during thyroid surgery

BACKGROUND

The purpose of this study was to identify predictors associated with graft function after parathyroid autotransplantation during thyroid surgery.

METHODS

One hundred fifty patients who underwent thyroid surgery with parathyroid autotransplantation were enrolled prospectively. During surgery, the misresected or devascularized parathyroid gland was autografted in the brachioradialis muscle of the forearm. Parathyroid hormone (PTH) levels in both arms were measured regularly after surgery. Patient age, sex, extent of surgery, and postoperative serum calcium levels were recorded.

RESULTS

Graft function was documented in 115 patients (76.7%). Univariate analysis revealed that graft function had a significant association with lower serum calcium level 1 day after surgery. The cutoff point was 2.11 mmol/L, which was confirmed by a receiver-operating characteristic (ROC) curve.

CONCLUSION

Low serum calcium levels in the early postoperative period may stimulate a functional recovery in an autografted parathyroid gland. Therefore, a moderate calcium supplement strategy was recommended for patients who underwent parathyroid autotransplantation during the early stage after total thyroidectomy.

Management Guidelines for Children with Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Previous guidelines for the management of thyroid nodules and cancers were geared toward adults. Compared with thyroid neoplasms in adults, however, those in the pediatric population exhibit differences in pathophysiology, clinical presentation, and long-term outcomes. Furthermore, therapy that may be recommended for an adult may not be appropriate for a child who is at low risk for death but at higher risk for long-term harm from overly aggressive treatment. For these reasons, unique guidelines for children and adolescents with thyroid tumors are needed.

METHODS

A task force commissioned by the American Thyroid Association (ATA) developed a series of clinically relevant questions pertaining to the management of children with thyroid nodules and differentiated thyroid cancer (DTC). Using an extensive literature search, primarily focused on studies that included subjects ≤18 years of age, the task force identified and reviewed relevant articles through April 2014. Recommendations were made based upon scientific evidence and expert opinion and were graded using a modified schema from the United States Preventive Services Task Force.

RESULTS

These inaugural guidelines provide recommendations for the evaluation and management of thyroid nodules in children and adolescents, including the role and interpretation of ultrasound, fine-needle aspiration cytology, and the management of benign nodules. Recommendations for the evaluation, treatment, and follow-up of children and adolescents with DTC are outlined and include preoperative staging, surgical management, postoperative staging, the role of radioactive iodine therapy, and goals for thyrotropin suppression. Management algorithms are proposed and separate recommendations for papillary and follicular thyroid cancers are provided.

CONCLUSIONS

In response to our charge as an independent task force appointed by the ATA, we developed recommendations based on scientific evidence and expert opinion for the management of thyroid nodules and DTC in children and adolescents. In our opinion, these represent the current optimal care for children and adolescents with these conditions.

Surgery for thyroid cancer

The incidence of thyroid cancer, particularly papillary thyroid cancer, is rising at an epidemic rate. The mainstay of treatment of most patients with thyroid cancer is surgery. Considerable controversy exists about the extent of thyroid surgery and lymph node resection in patients with thyroid cancer. Surgical experience in judgment and technique is required to achieve optimal patient outcomes.

Permanent hypoparathyroidism after completion total thyroidectomy as a second surgery: How do we avoid it?

A permanent hypoparathyroidism is a problematic complication of total thyroidectomy. In this study, we investigated its incidence and how to avoid it at the time of completion total thyroidectomy after hemithyroidectomy. Eight of the 154 patients who underwent completion total thyroidectomy as the second surgery (5%) after hemithyroidectomy (two-surgery group) showed a permanent hypothyroidism. Patients without parathyroid autotransplantation either at initial or second surgery were more likely to show a permanent hypoparathyroidism. In the subset of 74 patients in two-surgery group, who underwent bilateral central dissection, 6 (8%) had a permanent hypoparathyroidism. The incidence was higher than those in control group who underwent total thyroidectomy with bilateral central dissection at one time, which was 2%. However, all 6 patients showing a permanent hypoparathyroidsm underwent bilateral central dissection in initial surgery and none of the patients who underwent bilateral central dissection in twice had a permanent hypoparathyroidism. Taken together, we can conclude that 1) in initial surgery of hemithyroidectomy, we have to carefully search the parathyroid glands and if dissected, they should retrieved and autotransplanted to save the patients from a permanent hypoparathyroidism when they undergo second surgery in future, and 2) hemithyroidectomy with bilateral central dissection significantly increases the risk of permanent hypoparathyroidism and only ipsilateral dissection is better when we do not perform total thyroidectomy.

Long term parathyroid function following total parathyroidectomy with autotransplantation in adult patients with MEN2A

While there is no doubt that total thyroidectomy is necessary for medullary thyroid carcinoma (MTC) in multiple endocrine neoplasia type 2A (MEN2A) patients, there is still controversy regarding the management of the parathyroid glands. Although most, but not all, endocrine surgeons leave normal-appearing parathyroid glands in situ during thyroid surgery for MEN2A, we have employed total parathyroidectomy with autotransplantation. Between 1994 and 2006, 12 MEN2A patients underwent therapeutic total or completion thyroidectomy and lymph nodes dissection at least in the central compartment for MTC. Total or completion parathyroidectomy with autotransplantation was performed concurrently with above-mentioned surgery. All patients were over 25 years old, and the median age was 48.5 years. There were 5 males and 7 females from 8 families. The average number of transplanted parathyroid glands was 3. Serum calcium and intact PTH levels have been maintained during the median follow up of 107 months in all patients except for one who of died of advanced MTC one year after surgery. Total parathyroidectomy with autotransplantation at the time of primary surgery for MTC, i.e. total thyroidectomy with bilateral central neck dissection, is a feasible approach for managing the risk of hyperparathyroidism.

An introduction to managing medullary thyroid cancer

MTC is a rare neuroendocrine thyroid tumour accounting for 3% to 10% of all thyroid malignancies. It can occur in a sporadic and a hereditary clinical setting. Hereditary MTC may either occur alone (familial MTC, FMTC) or as part of multiple endocrine neoplasia (MEN) type 2A, or MEN 2B. These disorders are due to germline mutations in the RET (REarranged during Transfection) gene. In carriers of MEN 2B-associated RET mutations, prophylactic thyroidectomy is indicated before the first year of life. In the case of MEN 2A-associated germline RET mutations with a high-risk profile, total thyroidectomy is warranted before the age of 2 years and certainly before the age of 4 years. At that age the risk of invasive MTC and metastases is acceptably low. Depending on the type of RET mutation, thyroidectomy can take place at an older age in patients with a lower risk profile. In case of elevated basal or stimulated serum calcitonin, preventive surgery including total thyroidectomy and central compartment dissection should be performed regardless of age. When MTC presents as a palpable tumour, total thyroidectomy should be combined with extensive lymph node dissection of levels II-V on both sides and level VI to prevent locoregional recurrences.

Thyroid and parathyroid disease in children

Although diseases of the thyroid and parathyroid glands are relatively uncommon in children, the implications of missed diagnoses can be severe. This review describes the embryology, anatomy, and physiology of the thyroid and parathyroid glands, and focuses on significant benign and malignant pathologies of these glands.

Iodine 123 metaiodobenzylguanidine radio-guided navigation surgery for recurrent medullary thyroid carcinoma in a girl with multiple endocrine neoplasia type 2B

Multiple endocrine neoplasia type 2B (MEN 2B) is an inherited cancerous syndrome characterized by medullary thyroid carcinoma (MTC), adrenal pheochromocytoma, marfanoid habitus, and enteric ganglioneuromatosis. In this syndrome, a high frequency of persistent elevation of the serum calcitonin level, a sensitive marker for MTC, after total thyroidectomy has been reported, and the prognosis of such patients depends upon complete resection of recurrent MTC by repeated surgery. The authors performed iodine 123 metaiodobenzylguanidine ((123)I-MIBG) radio-guided navigation surgery for recurrent MTC in a 14-year-old girl with MEN 2B. She had undergone 4 neck operations, including total thyroidectomy at the age of 7 years. An intravenous injection of 100 MBq (123)I-MIBG was followed by the fifth surgery. At surgery, the cervical and upper mediastinal areas were filled with adhesional scar tissue, in which a gamma-scintillation probe conducted hot spots of isotope uptake by cancerous cells. Histopathology of resected specimens showed scattered nests of MTC cells corresponding to gamma-scintillation counts. Intraoperative (123)I-MIBG scanning is of substantial benefit for children with MEN 2B undergoing surgery for recurrent MTC.

Recovery of parathyroid function after total thyroidectomy: Long-term follow-up study

BACKGROUND

To prevent postoperative hypoparathyroidism following total thyroidectomy, the parathyroid glands are preserved in situ and/or resected or devascularized parathyroid glands are autotransplanted. A retrospective investigation was conducted utilizing biochemical and specific endocrine assessments to evaluate the difference in recovery of parathyroid function in the long term.

METHODS

A total of 103 patients underwent total thyroidectomy at Second Department of Surgery, School of Medicine, Kagawa University between 1990 and 1998. These patients were divided into a preservation group (n = 17), with only preserved glands in situ; a combination group (n = 72), consisting of patients with one or more parathyroid glands preserved in situ and one or more autotransplanted parathyroid glands; and an autotransplantation group (n = 14), with only transplanted glands.

RESULTS

The overall incidence of permanent hypoparathyroidism in the preservation group, the combination group, and the autotransplantation group was 0%, 1.4%, and 21.4%, respectively. The mean levels of intact parathyroid hormone in the preservation group, the combination group, and the autotransplantation group recovered to 102%, 107%, and 50% of the preoperative levels at 5-year follow up.

CONCLUSION

The results of the present study suggest that parathyroid glands should be preserved in situ whenever possible, to promote better recovery of postoperative function, and that only autotransplantation produces inadequate recovery of long-term function.

Parathyroid Autotransplantation during Total Thyroidectomy—Does the Number of Glands Transplanted Affect Outcome?

Parathyroid autotransplantation is a technique for ensuring the continued function of parathyroid tissue at the time of total thyroidectomy (TT). The aim of this study was to ascertain whether the number of parathyroids transplanted affects the incidence of temporary and permanent hypoparathyroidism. A retrospective cohort study included all patients undergoing a TT in a single unit between July 1998 and June 2003. The number of parathyroids transplanted, the final pathology, and the incidence of temporary and permanent hypoparathyroidism were documented. Fisher's exact test was used for statistical analysis. A total of 1196 patients underwent a TT during the 5 years studied. Of these, 306 (25.6%) had no parathyroids transplanted, 650 (54.3%), 206 (17.2%), 34 (2.8%) had 1,2, or 3 glands autotransplanted, respectively. The incidence of temporary hypoparathyroidism was 9.8% for no gland transplants, 11.9%, 15.1%, and 31.4% for 1,2,and 3 gland transplants, respectively (p < 0.05). The incidence of permanent hypoparathyroidism was 0.98%, 0.77%, 0.97%, and 0%, respectively (p = NS). The incidence of temporary hypoparathyroidism was higher when surgery was performed for Graves' disease. Temporary hypocalcemia is closely related to the number of autotransplanted parathyroids during TT. The long-term outcome is not affected by the number of parathyroids autotransplanted. A "ready selective" approach to parathyroid autotransplantation is an effective strategy for minimizing the rate of permanent hypoparathyroidism.

Parathyroid surgery in familial hyperparathyroid disorders

The management of hyperparathyroidism (HPT) in the setting of familial HPT differs between the specific syndromes and is generally complex because of the underlying disease, which predisposes patients to persistent and recurrent HPT. The basic principles of surgery include achieving and maintaining normocalcaemia for the longest time possible, avoiding both iatrogenic hypocalcaemia and operative complications, and facilitating future surgery for recurrent disease. Multiple endocrine neoplasia type 1 (MEN1) is treated with either subtotal parathyroidectomy or total parathyroidectomy with immediate heterotopic autotransplantation of parathyroid tissue. MEN2A, familial isolated HPT and HPT-associated with the hyperparathyroidism-jaw tumour (HPT-JT) syndrome typically can be treated with parathyroidectomy, i.e. subtotal or less. The increased risk of parathyroid cancer in HPT-JT requires special attention. Parathyroid surgery in familial HPT syndromes in the setting of underlying mutations in the calcium receptor (CASR) gene involves radical subtotal parathyroidectomy. Intraoperative parathyroid hormone (PTH) measurements may help guide the extent of parathyroid resection, particularly in the case of multigland HPT. The vast majority of patients with familial HPT who require surgery are best served with bilateral cervical explorations. However, minimally invasive parathyroidectomy (MIP) techniques that have become routine for sporadic HPT at selected institutions may be extrapolated to a subset of cases of familial HPT.

Frequent adverse events after treatment for childhood-onset differentiated thyroid carcinoma: a single institute experience

Since the mortality rate for childhood differentiated thyroid carcinoma is nearly zero, the focus must be to minimise morbidity following treatment. Our aim was to analyse early and late adverse events. Twenty-five of 26 children treated between 1962 and 2002 were evaluated. Median follow-up was 14.2 years (range 0.9-39.4 years). All underwent total thyroidectomy, 15 (60%) with lymph node dissection and 15 (60%) with adjuvant radio-iodide therapy. Mortality was zero. Seven developed recurrent disease, two developed a third recurrence. Twenty-one (84%) had > or =1 adverse event. Eight had permanent hypoparathyroidism (PH), six permanent recurrent nerve paralysis (PRNP) and two Horner's syndrome. Risk factors for PH and PRNP were total thyroidectomy with lymph node dissection (RR: 6.45, P = 0.015) and recurrent nerve tumour encasement (RR: 8.00, P = 0.001), respectively. Other adverse events were fatigue (n = 5), scar problems (n = 4) and chronic myeloid leukaemia (n = 1). These results emphasise the need to improve treatment strategies.

Management of hereditary thyroid cancer in children

Hereditary thyroid cancer in childhood occurs in the setting of Multiple Endocrine Neoplasia types 2A and 2B, and familial medullary thyroid carcinoma, FMTC. Prophylactic thyroidectomy in childhood has been recommended in patients found to have inherited mutations in the RET protooncogene, to prevent the development of medullary thyroid carcinoma. In this report are presented the clinical and genetic aspects of hereditary thyroid cancer in children, as well as surgical recommendations and medium-term outcome results.

Acceptable age for prophylactic surgery in children with multiple endocrine neoplasia type 2a

AIMS

Germline mutated RET proto-oncogene, causing multiple endocrine neoplasia (MEN)-2a syndrome is the indication for prophylactic total thyroidectomy. Literature regarding the risk and the extent of early surgical intervention is scarce and the optimum age for surgery is still controversial. To optimize management in these young children we evaluate our experience and results.

PATIENTS AND METHODS

From 1990 to 2001 preventive total thyroidectomy was performed in 13 MEN-2a gene carriers (4 boys and 9 girls; median age 7 (4-14) years). Preoperative assessment, surgical procedure, pathological examination, postoperative complications and treatment results were studied.

RESULTS

Surgery existed of a total thyroidectomy alone (n=3) in children with normal basal calcitonin and in combination with tracheo-esophageal exploration (n=6) or central compartment dissection (n=4) in case of abnormal calcitonin levels. Eight children presented with medullary thyroid cancer (MTC), three (median: 5 (4-12) years) with microscopic MTC and five (median 6 (4-14) years) with frank invasive MTC. Four of these five patients were younger than 6 years. Except for long-lasting hypoparathyroidism in one patient there were no complications. At a median follow-up of 6.5 years all patients are disease free.

CONCLUSION

MTC in RET mutated MEN-2a gene carriers in childhood are found at the age of 4 years. Therefore, DNA testing should be done preferably before that age. Preventive surgery can be performed safely at that age and may be limited to total thyroidectomy when baseline calcitonin levels are normal.

Parathyroid autotransplantation during thyroidectomy

Permanent hypoparathyroidism is a debilitating morbidity following thyroidectomy, with a reported incidence of up to 43%. Apart from meticulous dissection to preserve parathyroid glands and their blood supply, parathyroid autotransplantation (PA) has been increasingly employed to preserve parathyroid function. The adoption of PA during thyroidectomy has been reported to be associated with a low incidence of permanent hypoparathyroidism. Biochemical function of parathyroid autografts can be demonstrated objectively by forearm reimplantation or during long-term follow up. The clearest indication for PA is for inadvertently removed or devascularized parathyroid glands during thyroid surgery. Other strategies, including routine autotransplantation of at least one parathyroid gland, can be considered, but is associated with a high incidence of transient hypocalcaemia. Apart from refinement in technique to facilitate graft success, a reliable way to assess overall parathyroid function or viability of individual parathyroid gland may assist in monitoring parathyroid function and selecting patients requiring this procedure to prevent permanent hypoparathyroidism.

Childhood and adolescent thyroid carcinoma

OBJECTIVES

This analysis was performed to evaluate the influence of clinical and treatment factors on local tumor control, control of distant metastasis, survival, and complications in children and adolescents with thyroid carcinoma.

METHODS

The records of 56 children and adolescents with papillary and follicular carcinoma of the thyroid were reviewed. They ranged in age from 4 to 20 years. There were 43 females and 13 males. At diagnosis, 15 (27%) patients had disease confined to the thyroid, 34 (60%) had additional lymph node metastasis to the neck or upper mediastinum, and 7 (13%) also had lung metastasis. Treatment consisted of a total thyroidectomy in 48 patients, a subtotal thyroidectomy in 4 patients, and a lobectomy in 4 patients. All 56 patients received postoperative thyroid hormone suppressive therapy. (131)I was administered to 82% (46 of 56) of patients after their initial surgery.

RESULTS

The overall survival rate was 98% with a follow-up of 0.6-30.7 years (with a median follow-up of 11.0 years). The one death that occurred in this patient population was the result of a congenital heart defect and was unrelated to thyroid carcinoma. The 10-year progression-free survival rate was 61%. Nineteen patients (34%) experienced a recurrence of their thyroid carcinoma. The time to first recurrence of disease ranged from 8 months to 14.8 years (mean, 5.3 years). None of those with disease confined to the thyroid developed recurrent disease. The recurrence rate was 50% (17 of 34) in patients with lymph node metastasis and 29% (2 of 7) in patients with lung metastasis (P = 0.02). Tumor characteristics were evaluated for time to first recurrence utilizing the logistic likelihood ratio test to predict disease recurrence. Thyroid capsule invasion (P = 0.02), soft tissue invasion (P = 0.03), positive margins (P = 0.006), and tumor location at diagnosis (thyroid only vs. thyroid and lymph nodes vs. thyroid, lymph nodes, and lung metastasis, P = 0.02) were significant for developing recurrent disease. Patients younger than 15 years old at diagnosis were more likely to have more extensive tumor at diagnosis than patients who were 15 years and older (thyroid only vs. thyroid and lymph nodes vs. thyroid, lymph nodes, and lung metastasis, P = 0.02).

CONCLUSION

Carcinoma of the thyroid in children and adolescents has little risk of mortality but a high risk of recurrence. Younger patients present with a more advanced stage of disease and are more likely to have disease recurrence. Total thyroidectomy and lymph node dissection, followed by postoperative (131)I therapy, thyroid hormone replacement (suppressive) administration, and diligent surveillance are warranted.

Well-differentiated thyroid carcinoma in Hong Kong Chinese patients under 21 years of age: a 35-year experience

BACKGROUND

Sporadic well-differentiated thyroid cancer is an uncommon condition in children, adolescents, and young adults. It is associated with distinct clinicopathologic features and prognosis. The present study reviews our experience in management of this condition in ethnic Chinese in Hong Kong.

STUDY DESIGN

A retrospective study was performed to review the clinicopathologic features and outcomes of 34 patients less than 21 years of age with well-differentiated thyroid carcinoma over a 35-year period. Median followup was 15.2 years (range 1 to 32.5 years).

RESULTS

There were 27 girls and 7 boys with a median age of 19 years (range 10 to 21 years). None had previous history of irradiation. Twenty-eight patients had papillary and six had follicular carcinomas. Operative procedures included total thyroidectomy (n = 27) and unilateral lobectomy (n = 7) with concomitant neck dissection performed in nine patients. The median tumor size was 2 cm and extrathyroidal invasion was present in 19 tumors. Adjuvant radioactive iodine treatment was administered to 18 patients after total thyroidectomy. Disease progression or recurrence rate was 24% and 27% at 5 and 10 years, respectively. The presence of lymph node metastases was associated with a higher incidence of disease recurrence. One patient with advanced local disease died from tumor bed recurrence with anaplastic transformation 18 years after the initial operation.

CONCLUSIONS

Well-differentiated thyroid carcinoma is a relatively indolent tumor associated with good prognosis in young patients. Although death from this condition is rare, recurrence is frequent and longterm followup is necessary.

Routine parathyroid autotransplantation during thyroidectomy

BACKGROUND

Parathyroid autotransplantation (PTHAT) during thyroidectomy has been shown to reduce the incidence of permanent hypoparathyroidism. Although selective PTHAT is most commonly adopted, the value of routine PTHAT has not been well documented.

METHODS

From January, 1998 to March, 1999, an operative strategy incorporating routine autotransplantation of at least 1 parathyroid gland was used during thyroidectomy. The postoperative outcome of patients (n = 118) was evaluated and compared with patients (n = 271) operated during a policy of selective PTHAT (January, 1995 to October, 1997).

RESULTS

Two or more parathyroid glands were autotransplanted in 26 patients (22%) while 92 patients (78%) received autotransplantation of 1 parathyroid gland. Postoperative hypocalcemia occurred in 29 patients (25%) and 2 patients (1.7%) had permanent hypocalcemia develop. When a policy of selective PTHAT was adopted, 98 patients (36%) underwent PTHAT, and 5 patients developed permanent hypocalcemia (1.8%). The incidence of postoperative hypocalcemia was higher in patients who underwent routine PTHAT (25%) compared with that in patients who underwent selective PTHAT (15%) (P =.014). In addition, the operating time was significantly longer when routine PTHAT was adopted (153 minutes vs 130 minutes; P <.001).

CONCLUSIONS

A low incidence of permanent hypoparathyroidism can be achieved by either routine or selective PTHAT during thyroidectomy but routine PTHAT is associated with a high incidence of postoperative hypocalcemia.

Predictive DNA testing for multiple endocrine neoplasia 2: a therapeutic challenge of prophylactic thyroidectomy in very young children

BACKGROUND

Patients with multiple endocrine neoplasia (MEN) type 2 are at risk for early medullary thyroid carcinoma (MTC). Recently, the cloning of the ret oncogene has made it possible to identify patients at risk for MEN 2 syndrome with a high degree of reliability before presenting any symptoms.

METHODS

Children of families with MEN 2 were screened genetically if one of the parents was a known gene carrier of the RET proto-oncogene. If they were carriers, thyroidectomy was performed.

RESULTS

The authors report five children with MEN 2 who underwent prophylactic thyroidectomy irrespective of the results of calcitonin screening tests after genetic screening had shown that they were carrier of the RET proto-oncogene. Apart from a temporary hypocalcemia in one, the operations were uneventful. Pathology results showed MTC in three children of one family with MEN 2A at age 2, 3, and 6 years. In two families with MEN 2B the thyroidectomy specimen showed bilateral MTC in a 1-year-old and a 3-year-old child.

CONCLUSIONS

These findings show that MTC occurs at very young age in children with MEN 2. The authors advocate performing prophylactic thyroidectomy in the first year of life in children with MEN 2B and at age 2 years in children with MEN 2A to obtain an optimal cure rate.

Minimal-access parathyroid surgery using intraoperative parathyroid hormone assay

OBJECTIVES

Review the most current preoperative localization imaging techniques in patients with primary hyperparathyroidism and demonstrate their applicability to targeted tumor removal with intraoperative parathyroid hormone (PTH) monitoring.

STUDY DESIGN

Retrospective review of 40 consecutive patients undergoing parathyroid surgery with intraoperative PTH assay as the principal determinant of correction of the hyperparathyroid state. Details of the technology, cost analysis, and comparison with other management methods are discussed.

METHODS

The standard intact PTH chemiluminescent assay (Nichols Diagnostics) and modifications to allow accelerated intraoperative results are discussed in detail. The time intervals between completion of parathyroid excision and postremoval assay and subsequent laboratory investigation present a practical therapeutic algorithm.

RESULTS

Forty consecutive patients with hyperparathyroidism were treated surgically with intraoperative PTH as the determinant of satisfactory resolution of the disease state. In most instances, the surgical field was reduced to the targeted pathology identified by preoperative localization, and all patients became eucalcemic when this method was employed. Approximately half of eligible patients were treated under local anesthesia.

CONCLUSIONS

Intraoperative PTH assay has added a new dimension to primary and revision parathyroid surgery. It is cost-effective and accurate and may reduce the morbidity of surgical intervention in revision procedures.