Indications and results of video-assisted parathyroidectomy by a lateral approach in patients with primary hyperparathyroidism

Surgery for Sporadic Primary Hyperparathyroidism: Evolution over the Last Twenty Years in a Monocentric Setting

The sporadic parathyroid pathology of surgical interest is primarily limited to lesions that are the cause of hormonal hyperfunction (primary hyperparathyroidism). In recent years, parathyroid surgery has evolved significantly, and numerous minimally invasive parathyroidectomy techniques have been developed. In this study, we describe a single-center and well-documented case series of sporadic primary hyperparathyroidism, surgically treated by a single operator in the Endocrine Surgery Unit of the Surgical Clinic of the University of Florence-Careggi University Hospital, recorded and updated in a dedicated database that embraces the entire evolutionary timeframe of parathyroid surgery. From January 2000 to May 2020, 504 patients with a clinical and instrumental diagnosis of hyperparathyroidism were included in the study. The patients were divided into two groups, based on the application of intraoperative parathyroid hormone (ioPTH). The analysis shows that the use of ioPTH with the rapid method could be ineffective in helping surgeons in primary operations, especially when ultrasound and scintiscan are concordant. The advantages obtained by not using intraoperative PTH are not only economic. In fact, our data shows shorter operating and general anesthesia times and hospital stays, having an important impact on patient biological commitment. Furthermore, the significant reduction in operating time makes it possible to almost triple the volume of activity in the same unit of time available, with an undeniable advantage for the reduction of waiting lists. In recent years, minimally invasive approaches have allowed surgeons to reach the best compromise between invasiveness and aesthetic results.

Radioguided occult lesion localization for minimally-invasive parathyroidectomy without quick PTH monitoring and frozen section: impact of the learning curve

Objectives

Minimally-invasive parathyroidectomy (MIP) is a surgical procedure that reduces the duration of operation, hospital costs, and hypocalcemia, and shortens the length of hospital stay. This study addressed the important procedural details of the radioguided occult lesion localization (ROLL)-MIP technique and evaluated the consequences of the learning curve from a series of patients.

Patients and Methods

A total of 80 patients who underwent ROLL-MIP for a single parathyroid adenoma were included into this retrospective study. In order to analyze the effect of the learning curve, these subjects were then divided into 2 groups per time period and the operative times were compared. Group A consisted of 22 previously reported patients who served as the control group. Group B consisted of 58 consecutive patients.

Results

Serum calcium and parathyroid hormone (PTH) levels were normalized in all of the patients within 2 days and remained normal during the follow-up period (31 ± 18.5 months). None of the patients who underwent ROLL-guided parathyroidectomy suffered temporary or permanent recurrent laryngeal nerve injuries. Mean operation time (time from incision to excision of the adenoma) was 23 ± 6 min in Group A and 18 ± 7 min in Group B. Mean operative times were significantly shorter in group B.

Conclusion

The success of MIP administered with the ROLL technique in a single adenomatous patient was quite high. This method seems especially valuable in patients with atypically located or small adenomas.

Outcomes of Parathyroidectomy in Patients with Primary Hyperparathyroidism: A Systematic Review and Meta-analysis

BACKGROUND

Parathyroidectomy is a definitive treatment for primary hyperparathyroidism. Patients contemplating this intervention will benefit from knowledge regarding the expected outcomes and potential risks of the currently available surgical options.

PURPOSE

To appraise and summarize the available evidence regarding benefits and harms of minimally invasive parathyroidectomy (MIP) and bilateral neck exploration (BNE).

DATA SOURCES

A comprehensive search of multiple databases (MEDLINE, EMBASE, and Scopus) from each database's inception to September 2014 was performed.

STUDY SELECTION

Eligible studies evaluated patients with primary hyperparathyroidism undergoing MIP or BNE.

DATA EXTRACTION

Reviewers working independently and in duplicate extracted data and assessed the risk of bias.

DATA SYNTHESIS

We identified 82 observational studies and 6 randomized trials at moderate risk of bias. Most of them reported outcomes after MIP (n = 71). Using random-effects models to pool results across studies, the cure rate was 98 % (95 % CI 97-98 %, I (2) = 10 %) with BNE and 97 % (95 % CI 96-98 %, I (2) = 86 %) with MIP. Hypocalcemia occurred in 14 % (95 % CI 10-17 % I (2) = 93 %) of the BNE cases and in 2.3 % (95 % CI 1.6-3.1 %, I (2) = 87 %) with MIP (P < 0.001). There was a statistically significant lower risk of laryngeal nerve injury with MIP (0.3 %) than with BNE (0.9 %), but similar risk of infection (0.5 vs. 0.5 %) and mortality (0.1 vs. 0.5 %).

LIMITATIONS

The available evidence, mostly observational, is at moderate risk of bias, and limited by indirect comparisons and inconsistency for some outcomes (cure rate, hypocalcemia).

CONCLUSION

MIP and BNE are both effective surgical techniques for the treatment of primary hyperparathyroidism. The safety profile of MIP appears superior to BNE (lower rate of hypocalcemia and recurrent laryngeal nerve injury).

[Endoscopic lateral parathyroidectomy as surgical treatment for patients with primary hyperparathyroidism]

BACKGROUND

Most surgeons have rapidly accepted the use of minimally invasive surgical approaches for the treatment of primary hyperparathyroidism. The role of the endoscope in neck surgery is still being discussed due to its technical difficulty and complex patient selection criteria.

MATERIALS AND METHODS

A prospective study was conducted between April 2010 and April 2013. It included patients diagnosed with sporadic primary hyperparathyroidism (sPHPT) by locating a single adenoma using ultrasound and sestamibi scintigraphy imaging. All patients agreed to be included in the study. Experienced endocrine surgeons that had been trained in endocrine minimally invasive surgery performed the procedure. The same surgical technique was used in all of the cases. The demographic and clinical variables were evaluated. A descriptive analysis was performed on the data measuring mean, standard deviation, and range.

RESULTS

A total of 28 endoscopic lateral parathyroidectomies were performed. All patients were diagnosed with sporadic hyperparathyroidism sPHPT. The mean age was 68 years (59-89). No intraoperative complications were registered. Postoperative morbidity was comparable to that reported in the classical approach. A favourable outcome was observed in 27 of the 28 patients (96%) after a mean follow-up time of 22 (9 - 53) months.

CONCLUSIONS

An endoscopic approach for hyperparathyroidism sPHPT is feasible and reproducible, and it obtains comparable results to the classical open surgery. Several factors make this technique suitable for highly specialised hospitals with a high patient volume and specialised endocrine surgery units.

[Experience of transaxillary endoscopic thyroid surgery]

AIM

To compare the outcomes after open and endoscopic interventions on thyroid gland.

MATERIAL AND METHODS

We have retrospectively analyzed 158 interventions on thyroid gland for the period March 2014 - January 2016. Herewith, 21 interventions were performed endoscopically with transaxillary removal of specimen.

RESULTS

The study was designed in 2 groups - main (endoscopic surgery) and control (open surgery). There were 2 complications in the main group: intraoperative injury of cricoid cartilage by harmonic scalpel and unilateral subcutaneous emphysema of the neck and face. In the control group one patient had transient hypocalcemia.

CONCLUSION

Endoscopic thyroid surgery is technically feasible in certain patients, adequate technical equipment and sufficient experience of surgical team.

Meta-analysis of video-assisted versus open parathyroidectomy for primary hyperparathyroidism

The gold standard treatment of primary hyperparathyroidism was bilateral neck exploration. Video-assisted parathyroidectomy (VAP) facilitated less invasive surgery, however there is lack of evidence comparing it to open parathyroidectomy (OP). A meta-analysis was conducted according to the PRISMA guidelines to compare them. In three eligible randomized controlled trials (241 patients), VAP operative time (61.7 ± 12 min) was comparable to OP (59.9 ± 6 min), less early postoperative pain, higher cosmetic satisfaction (statistically not significant) and 4% failure rate (none in OP). 25% of VAP converted to OP. Hypocalcaemia was six-times less in VAP (RR 6.4). Careful patient selection and unequivocally positive preoperative localization are critical to the success of this procedure. To our knowledge, this is the first meta-analysis comparing the two techniques.

Initial surgery for benign primary hyperparathyroidism: an analysis of 1,300 patients in a teaching hospital

BACKGROUND

Success rates of initial surgery for primary hyperparathyroidism (pHPT) are greater than 95 % in specialized centers, mostly referring to single-surgeon experiences. The present study was performed to identify changes in clinical manifestations, diagnostic procedures, surgical strategies, and outcome of initial parathyroid interventions in a teaching hospital during the past 25 years with special regard to the surgical expertise.

METHODS

Clinical data of patients who underwent an initial neck exploration for benign pHPT between 1985 and 2010 at the University hospital Marburg were retrospectively evaluated. All data were analyzed particularly with regard to the implementation of additional pre- and intraoperative procedures and to the particular surgical strategy. In addition, operative results were furthermore analyzed with regard to the experience of the responsible surgeons.

RESULTS

An initial neck exploration for benign pHPT was performed in 1,300 patients. Of these, 1,035 patients had a bilateral cervical exploration (BCE) and 265 patients had a focused, minimally invasive parathyroidectomy (MIP). Cure rates did not differ between focused surgeries and BCE (98.9 vs. 98.3%, p = 0.596) after a mean follow-up of 33.4 (± 44.3) months. Postoperative transient hypoparathyroidism was significantly lower in the MIP group (11 vs. 47%, p < 0.0001). The rate of permanent recurrent laryngeal nerve palsies (0.4 vs. 2%, p = 0.064) and nonsurgical complications (0 vs. 1.4%, p = 0.0875) tended to be lower in the MIP group. Success and complication rates of chief surgeons (n = 2), attending surgeons (n = 20), and residents (56 < 3 years, 30 > 3 years) were similar, despite a significantly shorter operating time in the chief surgeon group (p < 0.01).

CONCLUSIONS

Despite the implementation of several diagnostic procedures and significant changes concerning the surgical strategy, high success rates of primary interventions for pHPT did not change over the past three decades. High success rates also can be achieved in a teaching hospital, provided that surgery is supervised by an experienced endocrine surgeon. MIP is the treatment of choice in patients with benign sporadic pHPT and positive preoperative localization studies.

Evaluation of conventional imaging techniques on preoperative localization in primary hyperparathyroidism

We aimed to evaluate the diagnostic and preoperative localization capacity of 99mTc methoxyisobutylnitrile (MIBI) parathyroid scintigraphy and ultrasonography (USG) in enlarged parathyroid glands in the primary hyperparathyroidism (pHPT) as well as the relationship between the success rate of these techniques and biochemical values. In this study, we retrospectively evaluated 39 patients with clinical and biological evidence of pHPT who referred to the university hospital for MIBI parathyroid scintigraphy. Patients were examined with USG and double-phase MIBI parathyroid scintigraphy for the detection of enlarged parathyroid glands. Preoperative serum intact parathyroid hormone (iPTH) levels, calcium (Ca), phosphate and alkaline phosphatase measurements were obtained. A total of 45 parathyroid lesions in 39 patients were reviewed. Thirty-four patients had a single adenoma and 5 patients with multi-gland disease had 11 abnormal parathyroid glands including three adenomas, whereas the remaining 8 glands showed hyperplasia. The overall sensitivities of MIBI parathyroid scintigraphy, USG and combined techniques were 85.3%, 72.5% and 90.4%, respectively; the positive predictive values (PPV) were 89.7%, 85.2% and 92.6%, respectively. The most successful approach for detection of enlarged parathyroid glands in hyperparathyroidism is the concurrent application of USG and MIBI parathyroid scintigraphy modalities. The concomitancy of thyroid diseases decreases the sensitivity of both MIBI parathyroid scintigraphy and USG in enlarged parathyroid glands.

A retrospective case-controlled study of video-assisted versus open minimally invasive parathyroidectomy

INTRODUCTION

Minimally invasive parathyroidectomy (MIP) with intraoperative parathyroid hormone assay (IOPTH) has successfully replaced conventional neck exploration in most patients with primary hyperparathyroidism (pHPT) and preoperatively localized parathyroid adenoma.

AIM

To compare outcomes of video-assisted MIP (MIVAP) to open MIP (OMIP).

MATERIAL AND METHODS

A retrospective case-controlled study of 455 patients with sporadic pHPT undergoing MIP with IOPTH at our institution in 2003-2012 was undertaken. The primary outcome measure was postoperative pain. Secondary outcome measures were: duration of surgery, recurrent laryngeal nerve (RLN) identification rate, conversion rate, length of hospital stay, cure rate, patients' satisfaction with cosmetic outcome, morbidity, costs, and diagnostic accuracy of IOPTH.

RESULTS

Of 455 patients with pHPT and a solitary parathyroid adenoma on preoperative imaging, 151 underwent MIVAP and 304 had OMIP. The following outcomes were favourable for MIVAP vs. OMIP: lower pain intensity during 24 h postoperatively (p < 0.001), lower analgesia request rate (p < 0.001), lower analgesics consumption (p < 0.001), higher recurrent laryngeal nerve identification rate (p < 0.001), shorter scar length (p < 0.001), and better cosmetic satisfaction at 1 month (p = 0.013) and at 6 months (p = 0.024) after surgery. However, MIVAP vs. OMIP had longer duration of surgery (p < 0.001), and was more expensive (p < 0.001). No differences were noted in the conversion rate, length of hospital stay, and morbidity.

CONCLUSIONS

Both MIVAP and OMIP approaches were equally safe and effective. However, the outcomes of MIVAP operations were superior to OMIP in terms of lesser postoperative pain, lower analgesics consumption, and better cosmetic satisfaction resulting from a smaller scar.

Thyroid diseases cause mismatch between MIBI scan and neck ultrasound in the diagnosis of hyperfunctioning parathyroids: usefulness of FNA-PTH assay

DESIGN

To evaluate the efficacy of the main tools in the diagnostic localization of hyperfunctioning parathyroids (HP) in primary hyperparathyroidism (pHPT) with concomitant thyroid diseases.

METHODS

Forty-three patients with pHPT associated with nodular goiter (NG, n=32) and/or autoimmune thyroid diseases (AITDs, n=11) for a total of 63 neck lesions were considered. Sixteen patients displaying HP (16 lesions), unequivocally localized by sestaMIBI scintigraphy (MIBI) and neck ultrasound (US) (group I), were compared with 27 patients (47 neck lesions) displaying equivocal parathyroid localization (group II). In all cases, neck US, MIBI scan, cytology, and parathyroid hormone assay in fine-needle aspiration washout fluid (FNA-PTH) were performed. All patients finally underwent surgery.

RESULTS

According to histological examination, high FNA-PTH values (>103 pg/ml) correctly identified all HP in both groups of patients (100% of sensitivity and specificity). Both MIBI and US correctly identified all HP only in group I patients; in contrast, four patterns of mismatch between these techniques were observed in group II patients, leading to low diagnostic performances of neck US (71.4% sensitivity and 78.9% specificity) and of MIBI scan (35.7% sensitivity and 42.1% specificity). The latter was due to both false-negative (mainly in AITD) and false-positive (mainly in NG) scan images.

CONCLUSIONS

Coexistent thyroid diseases are responsible for mismatch between MIBI and US images resulting in equivocal HP localization. In these cases, FNA-PTH resulted in the most accurate tool to identify HP. However, although safe, it should be advised only to patients with uncertain HP localization.

The results of surgery for mediastinal parathyroid tumors: a comparative study of 63 patients

PURPOSE

Parathyroidectomy for ectopic mediastinal hyperfunctioning glands could be performed by transcervical approach, sternotomy, thoracotomy, and recently by thoracoscopic and mediastinoscopic approaches. This study was aimed to analyze the results of traditional and video-assisted parathyroidectomy for mediastinal benign hyperfunctioning glands.

METHODS

Fifty-one upper mediastinal exploration by a conventional cervicotomy, 12 by video-assisted approaches (two thoracoscopy and 10 transcervical mediastinoscopy) and six by sternotomy were performed in 63 patients with primary hyperparathyroidism.

RESULTS

Video-assisted and sternotomic parathyroid explorations achieved biochemical cure in all cases; following conventional transcervical mediastinal exploration, a persistent hyperparathyroidism occurred in 11.8% of patients, who were subsequently cured by sternotomic approach. No complications occurred after video-assisted parathyroidectomy, while an overall morbidity rate of 50% and 10% was found after sternotomic and conventional cervicotomic approaches. Postoperative pain and hospital stay were significantly increased following sternotomy; patient's subjective cosmetic satisfaction was significantly higher after video-assisted and conventional cervicotomic approaches.

CONCLUSIONS

Conventional cervicotomic parathyroidectomy may achieve satisfactory results, especially for upper mediastinal glands. Sternotomic approaches are effective, but should be limited because of invasiveness and increased morbidity. In case of deep and lower hyperfunctioning mediastinal parathyroids, video-assisted approaches represent a less invasive, effective, and safe alternative and might be the technique of choice.

Clinical utility of ultrasound and 99mTc sestamibi SPECT/CT for preoperative localization of parathyroid adenoma in patients with primary hyperparathyroidism

AIM

To evaluate the accuracy of ultrasound and parathyroid scintigraphy using single photon-emission computed tomography/computed tomography (SPECT/CT) for the preoperative localization of solitary parathyroid adenomas in patients with primary hyperparathyroidism who would be suitable for minimally invasive parathyroid surgery.

MATERIALS AND METHODS

Retrospective study of 63 consecutive patients with biochemical evidence of primary hyperparathyroidism referred for preoperative localization of parathyroid adenoma that proceeded to surgery in the same institution. All patients underwent high-resolution ultrasound and Technetium-99m sestamibi scintigraphy with planar and SPECT/CT imaging. The accuracy of preoperative imaging was compared to surgical and histological findings as the reference standard.

RESULTS

Fifty-nine patients had solitary parathyroid adenomas, three patients had multiglandular hyperplasia, and one patient had multiple parathyroid adenomas confirmed at surgery and histology. Thirty-five solitary parathyroid adenomas were identified preoperatively with ultrasound (64%) and 53 with SPECT-CT (90%). Concordant ultrasound and SPECT/CT findings were found in 35 cases (59%). An additional three adenomas were found with ultrasound alone and 18 adenomas with SPECT/CT alone. Fifty-one of the 56 adenomas localized using combined ultrasound and SPECT/CT were found at the expected sites during surgery. Combined ultrasound and SPECT/CT has an overall sensitivity of 95% and accuracy of 91% for the preoperative localization of solitary parathyroid adenomas.

CONCLUSIONS

The combination of ultrasound and SPECT/CT has incremental value in accurately localizing solitary parathyroid adenomas over either technique alone, and allows selection of patients with primary hyperparathyroidism who would be suitable for minimally invasive surgery.

99mTc-MIBI pinhole SPECT in primary hyperparathyroidism: comparison with conventional SPECT, planar scintigraphy and ultrasonography

PURPOSE

A pinhole collimator is routinely used to increase the resolution of scintigraphy. This prospective study was conducted to determine the interest of (99m)Tc-MIBI pinhole single-photon emission computed tomography (SPECT) for the preoperative localisation of parathyroid lesions in primary hyperparathyroidism.

METHODS

All patients underwent a neck ultrasonography (US), (99m)TcO4- and (99m)Tc-MIBI planar images and two consecutive SPECT with a parallel (C-SPECT) and a pinhole collimator (P-SPECT). P-SPECT was performed with a tilted detector equipped with a pinhole collimator and reconstructed with a dedicated OSEM algorithm. A diagnostic confidence score (CS) was assigned to each procedure considering intensity and extra-thyroidal location of suspected lesions: 0 = negative, 1 = doubtful, 2 = moderately positive, 3 = positive. The results of these preoperative localisation studies were compared with surgical, pathological and 6-month biological findings.

RESULTS

Fifty-one patients cured after surgery were included. Surgery revealed 55 lesions (median weight 0.5 g, 11 in ectopy). Sensitivities of US, planar imaging, C-SPECT and P-SPECT were, respectively, 51, 76, 82 and 87%. Nine glands were only detected by tomography and five glands only by P-SPECT. 99mTc-MIBI/99mTcO4- planar scans and P-SPECT were complementary and, when combined together, showed the highest sensitivity (93%). Compared with planar imaging and C-SPECT, P-SPECT increased CS for 42 and 53% of lesions, respectively, and contributed to markedly reduce the number of uncertain results.

CONCLUSIONS

A combination of planar 99mTc-MIBI/99mTcO4- scintigraphy and P-SPECT appears to be a highly accurate preoperative imaging procedure in primary hyperparathyroidism.

Primary Hyperparathyroidism

Primary hyperparathyroidism (PHPT) is classically thought of as the somatic manifestation of hypercalcemia in which patients suffer from a variety of complaints including abdominal pain, nephrolithiasis, osteopenia, and mental status changes. Contemporary PHPT patients are generally free of somatic manifestations and are most often diagnosed when routine biochemical testing shows an elevated serum calcium level. The modern day patient may present with much more subtle neurocognitive symptoms including fatigue, lethargy, muscle weakness, depression, and cognitive impairment. Advances in imaging technology, intraoperative parathyroid hormone measurement, and surgical technique now allow parathyroidectomy to be performed using a focused approach without the absolute need of a four-gland exploration. Minimally invasive techniques allow the procedure to be accomplished under local anesthesia on an outpatient basis. This brief review summarizes the presentation, biochemical evaluation, operative intervention, and follow-up care of the modern day PHPT patient.

Minimally invasive parathyroidectomy without intraoperative parathyroid hormone monitoring in patients with primary hyperparathyroidism

BACKGROUND

Minimally invasive parathyroidectomy (MIP) is the preferred operation for patients with primary hyperparathyroidism (HPT) and positive preoperative imaging. This non-randomized case series assessed the long-term results of MIP performed without the use of intraoperative parathyroid hormone (ioPTH) monitoring.

METHODS

The study involved prospective collection of demographic, biochemical and operative details on a consecutive, unselected cohort of 298 patients who underwent surgery for non-familial primary HPT during a 5-year interval. The mean preoperative serum calcium level was 3.00 mmol/l with a mean parathyroid hormone concentration of 25.8 pmol/l. (99m)Tc-labelled sestamibi scanning and neck ultrasonography were performed in 262 patients.

RESULTS

Sestamibi scan showed unilateral uptake in 182 patients and a single parathyroid adenoma was confirmed on ultrasonography in 161 patients. MIP was performed in 150 patients. The mean duration of operation was 25 (range 8-65) min. Four patients needed conversion to conventional neck exploration. There was one postoperative haematoma and three cases of temporary recurrent laryngeal nerve neuropraxia. All but four patients were normocalcaemic after MIP. All the parathyroid tumours removed were adenomas, with a mean weight of 1.3 (range 0.1-17.4) g. No patient developed recurrent HPT after a median follow-up of 16 (range 3-48) months.

CONCLUSION

The outcome of MIP without ioPTH monitoring was comparable to that reported in series that used ioPTH monitoring.

A prospective evaluation of preoperative localization by technetium-99m sestamibi scintigraphy and ultrasonography in primary hyperparathyroidism

BACKGROUND

Ultrasonography (USG) and technetium-99m sestamibi (MIBI) scintigraphy are commonly used imaging modalities in the era of minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism (pHPT). However, their relative importance and actual contribution to MIP have not been prospectively assessed.

METHODS

A total of 100 consecutive pHPT patients planning for MIP were recruited. Both USG and MIBI findings were correlated with intraoperative findings and postoperative outcome. Clinicopathologic factors were examined for potential association with a correct localizing result.

RESULTS

Thirty men and 70 women (age range 13 to 93 years [median 55.5]) were included in the study. The final pathology included 98 patients with solitary adenoma and 2 patients with multiglandular disease. The sensitivities, accuracies, and positive predicted values for USG and MIBI alone were 57% vs 89%, 56% vs 85%, and 97% vs 94%, respectively. Correctly localized adenomas were significantly heavier than incorrectly localized ones.

CONCLUSIONS

MIBI is preferred over USG in pHPT patients planning for MIP. Weight of adenoma appeared to be the only clinicopathologic factor determining localization accuracy.

Feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) 99mTc-sestamibi protocol

Aim of the present study was to investigate the feasibility and long-term results of focused radioguided parathyroidectomy using a "low" 37 MBq (1 mCi) ^99mTc-sestamibi dose protocol compared to conventional "high 740 MBq (20 mCi) ^99mTc-sestamibi dose protocol" in patients with primary hyperparathyroidism (PHPT). The data of focused radioguided surgery obtained in a group of 320 consecutive PHPT patients with high probability of the presence of a solitary parathyroid adenoma (PA) were studied. All patients underwent preoperative imaging work-up of double-tracer ^99mTc-pertechnetate/^99mTc-sestamibi subtraction parathyroid scintigraphy (Sestamibi scintigraphy) and high resolution neck ultrasound (US). In 301/320 patients (96.6%) focused minimally invasive radioguided surgery was successfully performed by administering a "low" 37 MBq (1 mCi) ^99mTc-sestamibi dose in the operating room 10 minutes before operation. No major intraoperative complications were recorded. Focused radioguided surgery required a mean time of 32 min and a mean hospital stay of 1.2 days. Local anesthesia was applied in 75 patients, 66 of whom (88%) were patients older than 65 years with comorbidities contraindicating general anesthesia. No case of persistent or recurrent PHPT was observed during post-surgical follow-up (range = 18–70 months; mean +/- SD = 15.3 +/- 9.1 months). Radiation exposure dose to the operating surgeon was 1.2 μSi/hour with the "low 37 MBq (1 mCi) ^99mTc-sestamibi dose", and less than 1.0 μSi/hour for the other operating-room personnel. Focused low dose radioguided parathyroidectomy is a safe and effective means to localize parathyroid adenomas in patients affected by solitary PA thus reducing by 20 fold the radiation exposure dose to the patients and operating room personnel.

Minimally invasive radio-guided parathyroidectomy: long-term results with the ‘low 99mTc-sestamibi protocol’

BACKGROUND

This paper reports the results of minimally invasive radio-guided surgery (MIRS) performed in a large group of 280 consecutive patients affected by primary hyperparathyroidism (PHPT) and with a high probability of being affected by a solitary parathyroid adenoma before surgery.

METHODS

The probability of a solitary parathyroid adenoma was established by evaluating the patients with a single-day imaging protocol based on parathyroid double-tracer scintigraphy and high resolution neck ultrasonography. MIRS was performed successfully in 269 (96.1%) patients. MIRS consisted of a very low dose (37 MBq (1 mCi)) of Tc-sestamibi, given by intravenous injection, in the operating theatre a few minutes before surgery, thus allowing the radiation exposure dose to the patient and operating theatre personnel to be minimized (< 1.5 muSv.h to the surgeon).

RESULTS

No major intraoperative complication was recorded in our series. Transient hypocalcaemia was observed in 8% of patients. MIRS required a mean duration time of 33 min and a mean hospital stay of 1.2 days. Local anaesthesia was successfully performed in 71 patients, 63 of whom were elderly and with concomitant invalidating diseases contraindicating general anaesthesia. No case of disease relapse was observed during the subsequent follow-up.

CONCLUSION

MIRS using the 'low sestamibi protocol' is a safe and effective treatment in PHPT patients with a high likelihood of a solitary parathyroid adenoma at preoperative imaging.

Role of 99mTc-sestamibi SPECT in accurate selection of primary hyperparathyroid patients for minimally invasive radio-guided surgery

PURPOSE

A prerequisite for optimum minimally invasive radio-guided surgery (MIRS) for primary hyperparathyroidism (PHPT) is the demonstration of significant uptake of (99m)Tc-sestamibi in a parathyroid adenoma (PA). The aim of this study was to evaluate the clinical role or (99m)Tc-sestamibi SPECT in selecting patients for this procedure.

METHODS

Fifty-four consecutive PHPT patients were evaluated by single-session (99m)Tc-pertechnetate/(99m)Tc-sestamibi planar subtraction scintigraphy, followed by (99m)Tc-sestamibi SPECT acquisition to localise hyperfunctioning PAs and assist in planning the surgical approach.

RESULTS

Scintigraphy showed the presence of a solitary PA in 47/54 patients (87%) and two or more PAs in four patients (7.4%); it was negative in the remaining three patients (5.6%). The overall sensitivity of (99m)Tc-sestamibi scintigraphy was 94.6%. In 7/54 patients, the PA was located deep in the para-oesophageal/paratracheal space. So far, 22 patients with scintigraphic evidence of a solitary PA (in four of whom the PA was located deep in the neck) have undergone successful MIRS using the low 37 MBq (1 mCi) (99m)Tc-sestamibi dose protocol. Intraoperative quick parathyroid hormone (QPTH) assay demonstrated a fall in all 22 patients, thus confirming successful removal of the hyperfunctioning PA. No major surgical complications were observed. After a period of follow-up ranging between 6 and 27 months (median 13 months), no case of persistent/recurrent PHPT was recorded. When comparing the parathyroid to background (P/B) ratio measured at planar and SPECT preoperative scintigraphy with that measured intraoperatively with the gamma probe, a good linear correlation was found between the SPECT and the intraoperative gamma probe measurements (r=0.89; p<0.01) but no correlation was found with planar scintigraphic data.

CONCLUSION

Our preliminary data suggest that measurement of the P/B ratio by means of (99m)Tc-sestamibi SPECT is more accurate in predicting the intraoperative measurements with the gamma probe. In this respect, a preoperative (99m)Tc-sestamibi SPECT acquisition should be recommended for better selection of PHPT patients in whom a MIRS approach can be offered.

Minimally invasive radioguided parathyroidectomy

We reported here the data on minimally invasive radio-guided parathyroidectomy (MIRP) in a large group of 253 patients enrolled from the whole series of 355 consecutive patients affected by primary hyperparathyroidism (P-HPT) referred to our center. On the basis of preoperative imaging including Sestamibi scintigraphy and neck ultrasound (US), 263 patients (74% of the whole series) with evidence of a solitary parathyroid adenoma (PA) and a normal thyroid gland were addressed to MIRP and in 253 (96%) of them this minimally invasive neck exploration was successfully performed. The MIRP protocol developed in our center consisted of a very low 1 mCi Sestamibi injection in the operating room a few minutes before the start of intervention, thus minimizing the radiation exposure dose to the patient and personnel. No major intraoperative complication was recorded in patients treated by MIRP and only a transient hypocalcemia in 8.5% of cases. The mean duration time for MIRP was 35 min and the mean hospital stay 1.2 days. Local anesthesia was also performed in 62 patients, 54 of whom were elderly patients with concomitant invalidating diseases contraindicating general anesthesia. No HPT relapse was observed during subsequent follow-up. The gamma probe was used also during bilateral neck exploration in the group of 92 patients excluded from MIRP. The most frequent cause of exclusion from MIRP in our series was the presence of concomitant Sestamibi avid thyroid nodules (68.5% of cases) that can give false positive results at radio-guided surgery. In conclusion, MIRP is an effective treatment in patients with a high likelihood of a solitary PA and a normal thyroid gland at scintigraphy and US so that an accurate preoperative localizing imaging is required for MIRP. A low 1 mCi Sestamibi dose appears sufficient to perform MIRP. Patients with concomitant Sestamibi avid thyroid nodules should be excluded from MIRP.

Are frozen sections useful and cost-effective in the era of intraoperative qPTH assays?

BACKGROUND

Since intraoperative quick parathormone (IOqPTH) assays are available, the role of frozen sections (FS) during parathyroid exploration has become questionable. This study compares the results of FS and IOqPTH in primary hyperparathyroidism (pHPT).

METHODS

FS and IOqPTH assays were performed in 102 patients who underwent bilateral neck explorations or targeted parathyroidectomy for pHPT. The operation was considered complete when both an IOqPTH drop >50% and a FS diagnosis of parathyroid adenoma were obtained.

RESULTS

Cure was achieved in all patients. Potential pitfalls for successful operation were encountered in 14 patients with multiglandular diseases and in 4 patients who had nonparathyroid tissue removed. FS correctly predicted the definitive histologic diagnosis with an accuracy of 81%. FS failures potentially misguided the operative therapy in 19% (14 insufficient explorations and 5 unnecessarily prolonged explorations), while IOqPTH identified all potential pitfalls and correctly guided the operative strategy, suggesting further exploration, in 100% of cases (P < .0001). After bilateral neck exploration, FS and IOqPTH correctly guided operative strategy in 86% and 100% of cases, respectively (P < .05), but both techniques were never indispensable, because potential pitfalls were already evident by macroscopic intraoperative appearance. The turnaround time and costs for IOqPTH were lower (P < .001).

CONCLUSIONS

The role of FS should be reconsidered, since it can misguide the operative strategy. IOqPTH is indispensable for a focused approach and, although unnecessary in bilateral neck exploration, is more useful and cost-effective than FS.

Familial parathyroid hyperplasia: is there a place for minimally invasive surgery? Description of the first treated case

While the majority of patients affected with sporadic primary hyperparathyroidism (sPHPT) can be selected for minimal access surgery, patients affected with 4-gland hyperplasia still do not represent an indication for it. Minimally invasive video-assisted parathyroidectomy (MIVAP) was introduced in 1996; this technique relies on a single central incision and external retraction and therefore allows a bilateral neck exploration. This was the case of a 27-yr-old female with familial primary hyperparathyroidism (FPHPT). Three enlarged glands were immediately identified in orthotopic positions and the fourth was intrathyroideal. A subtotal parathyroidectomy was then performed, leaving a small fragment of the inferior right gland and completed with the cervical thymectomy by inverting the positions of the camera and the retractor assistants with regard to the positions originally described. Quick intraoperative PTH assay (QPTH) confirmed the surgical cure of the disease.

Parathyroid surgery: we only need a minimal surgical approach

Minimally invasive surgery for the treatment of primary hyperparathyroidism is currently used by the greatest majority of authors. Extensive literature has shown that results and complication rates are comparable to those obtained by extensive neck bilateral exploration performed via standard open surgery. Neither recurrence rate nor persistence rate have increased over the last 7 yr since the introduction of these minimal access procedures. The dramatic improvement of localization studies and the introduction of intraoperative parathyroid hormone measurement constitute the basis for this change of attitude among surgeons; the shift has also been supported by the utilization of the new endoscopic techniques recently introduced. Bilateral neck exploration now seems to be confined only to a slight minority of patients, in particular when a reoperation or the removal of a big goiter is needed.

Primary hyperparathyroidism. Update on pathophysiology, clinical presentation and surgical treatment

The most important step in calcium homeostasis is the regulation of parathyroid hormone (PTH) secretion. The discovery and characterization of the calcium sensing receptor (CaR) of the parathyroid cell has led to a better understanding not only of the physiology of the parathyroid glands, but also of the development of hyperparathyroidism. Drugs acting on CaR can now be designed to treat hyperparathyroidism and osteoporosis. The workshop on primary hyperparathyroidism held at the National Institutes of Health in 2002 has recommended new guidelines for the treatment of asymptomatic hyperparathyroidism. Controversy still exists regarding the treatment of patients with non-classical symptoms, such as weakness, fatigue and depression. Primary hyperparathyroidism as a risk factor for cardiovascular disease and mortality is also debated. Improved techniques for the preoperative localization of pathological parathyroid glands have led to a shift in surgical strategy: surgeons abandon the traditional bilateral neck exploration in favor of a more limited approach. This change of strategy has not been based on the results of prospective randomized studies and the long term results are not known.

Cirugía cervical endoscópica

The beginning of cervicoscopy dates back to the first laparoscopic parathyroidectomy in 1996. This operation, with its distinct variants, has today become a valid therapeutic option in many well-regarded centers. Later on endoscopic or video-assisted thyroidectomy was introduced, despite the limits imposed by the large size of the gland on its removal. Consequently, this technique is indicated in a small number of patients but both parathyroidectomy and thyroidectomy provide significant advantages over conventional surgery, which have been demonstrated in prospective studies. The main advantages are a better cosmetic outcome and a less distressing postoperative course. Both approaches have been proved to be safe and feasible in any surgical background and their complication rate is similar to that of traditional open surgery of the neck. Videoscopic access to neck lymph nodes (central and lateral compartments) seems to be highly promising, whereas other fields of application such as carotid artery surgery and spine surgery are still the object of experimental studies. Consequently, cervicoscopy should be considered an important surgical tool which already shows great possibilities but which could be further improved.

Sestamibi scan-directed parathyroid surgery: potentially high failure rate without measurement of intraoperative parathyroid hormone

The present study evaluated sestamibi scan-directed parathyroidectomy with intraoperative parathyroid hormone (PTH) assessment (ioPTH). The preoperative sestamibi scintigraphies were compared with the intraoperative findings for 103 patients undergoing first exploration for sporadic primary hyperparathyroidism (pHPT). Data were collected prospectively. Ninety-nine patients (96%) were cured. Patients with persistent pHPT (n = 4) all had an incorrect scintigram as well as an insufficient decline of ioPTH. At operation, 90 patients (87%) had solitary parathyroid adenoma; 12 patients had multiglandular disease. In one patient no enlarged parathyroid gland was found. Overall 77 of 118 abnormal glands (65%) were correctly identified by sestamibi scintigraphy. The sensitivity for localizing a single parathyroid adenoma was 80%. Patients with incorrect scintigrams had a higher proportion of upper pole adenomas than patients with correct scans. High glandular weight and high level of serum PTH were important factors for detectability. Sestamibi scintigraphy did not predict multiglandular disease. However, the use of ioPTH identified 8 of the 9 patients with a positive scan (a solitary focus) and multiglandular disease. In contrast, false-negative ioPTH led to four unnecessary bilateral explorations in the 63 patients with a scan-identified adenoma. With the help of ioPTH, a focused parathyroidectomy was accomplished in 43% of scan-negative patients with a solitary adenoma. In conclusion, sestamibi scintigraphy is an acceptable method for localizing a solitary parathyroid adenoma. However, the technique alone does not reliably predict multiglandular disease. Potentially the failure rate in scan-directed parathyroidectomy could increase, with up to 10% of patients without ioPTH.

Conventional bilateral cervical exploration versus open minimally invasive parathyroidectomy under local anaesthesia for primary hyperparathyroidism

Background

Minimally invasive parathyroidectomy (MIP) has been introduced for the treatment of patients with primary hyperparathyroidism (pHPT). Thus far, only one randomized trial has compared video-assisted MIP with conventional bilateral cervical exploration (BCE). The value of open MIP is therefore not known.

Methods

Fifty patients with a solitary parathyroid adenoma localized before surgery by sestamibi scintigraphy were randomized to undergo BCE under general anaesthesia (n = 25) or targeted MIP via a 2-cm incision using local anaesthesia (n = 25). Postoperative hypocalcaemia was the primary endpoint. Secondary outcome measures were operating time, complications, postoperative analgesia and recurrent disease. Follow-up was carried out at 1 and 6 months.

Results

All patients who underwent BCE and 24 of those who had MIP were cured by the primary operation. Operating time was 22 min shorter in the MIP group (P = 0·024). Serum levels of calcium were slightly lower during the first 4 days after surgery in the BCE group (P = 0·022). No other no significant differences were found.

Conclusion

Targeted MIP using local anaesthesia reduces operating time and causes less postoperative biochemical hypocalcaemia compared with bilateral neck exploration.

Results of video-assisted parathyroidectomy: single institution's six-year experience

Endoscopic surgery for primary hyperparathyroidism (PHPT) started in 1996 with a parathyroidectomy performed by Michel Gagner. The technique we propose and have been using for 6 years is based on a unique central access and external retraction. From February 1997 to October 2003, 370 of 520 patients affected with PHPT (71%) underwent minimally invasive video-assisted parathyroidectomy (MIVAP). There were 72 men and 298 women, with a mean age of 55.8 years. Twenty-four patients (6.5%) of the 370 in this series underwent MIVAP under loco-regional anesthesia, and the others had general anesthesia. Eleven patients were lost to follow-up. Surgical cure of PHPT was achieved in 353 patients (98,3%), as confirmed by a median follow-up of 35.1 months (range: 2-82 months). Video-assisted exploration was successfully performed in 350 patients (94%). The mean operative time was 36.2 minutes. In 21 cases (5.6%) a concomitant procedure was performed: a thyroid lobectomy in 14 cases and a total thyroidectomy in 7 cases. Patients were generally discharged the day after surgery. Most of the patients (91%) were satisfied with the cosmetic result 6 or more months after the procedure. Complications developed in 14 cases: 10 cases (2.7%) of transient hypoparathyroidism 3 cases (0.8%) of definitive palsies of the recurrent nerve, and 1 case of postoperative bleeding (0.27%). After 6 years of experience, MIVAP appears to be as safe and curative as traditional surgery, with better cosmetic results and better postoperative outcome.

Endoscopic parathyroid surgery: results of 365 consecutive procedures

In recent years, several series have documented the feasibility of endoscopic approaches for parathyroid diseases. We performed a retrospective study to evaluate the results of endoscopic parathyroidectomy (EP) in the management of our patients with primary hyperparathyroidism (PHPT). During a 5.5 year period (1998-2003), we operated on 644 patients with PHPT. EP was proposed for patients with sporadic PHPT, without associated goiter, and without previous neck surgery in whom a single adenoma was localized by means of sonography and sestamibi scanning. EP was performed by the lateral approach with insufflation for patients with an adenoma located deep in the neck and by a gasless midline approach for patients whose adenoma was located anteriorly. A quick parathyroid (QPTH) assay was used during the surgical procedures. Among 644 patients with PHPT, 279 (43.3%) were not eligible for EP for the following reasons: associated nodular goiter (116 cases), previous neck surgery (52 cases), suspicion of multiglandular disease (31 cases), lack of preoperative localization (61 cases), and miscellaneous causes (19 cases). EP was performed in 365 patients with sporadic PHPT: 339 lateral access, 25 midline access, and one thoracoscopy. The median operating time was 49 minutes (16-130 minutes). Conversion to conventional parathyroidectomy was required in 49 patients (13.4%) for these reasons: missed adenomas (14 cases), difficulty with the dissection (8 cases), multiglandular disease correctly predicted by QPTH (11 cases), false-negative QPTH assay results (4 cases), false-positive sestamibi scan results (11 cases), and 1 false-positive sonography result. One patient presented with definitive recurrent nerve palsy. Three patients remained hypercalcemic, and one other patient had recurrent hypercalcemia. In conclusion, EP can be proposed for more than half of the patients with PHPT. Immediate results of EP are similar to those obtained with conventional parathyroidectomy, but no conclusions can be drawn in terms of the influence of EP on the outcome of the patients operated on for PHPT.

Minimally invasive radioguided parathyroidectomy: an attractive therapeutic option for elderly patients with primary hyperparathyroidism

BACKGROUND AND AIM

Surgery for primary hyperparathyroidism (PHPT) due to a solitary parathyroid adenoma (PA) is moving from traditional bilateral neck exploration (BNE) towards the use of limited neck exploration. The aim of the present study was to define the efficacy of minimally invasive radioguided surgery (MIRS) in PHPT patients with a high probability of a solitary PA with particular regard to benefits achievable in elderly patients.

PATIENTS AND METHODS

The study population included a total of 266 consecutive PHPT patients who had undergone surgery at our centre between September 1999 and February 2003. Preoperative imaging consisted of [Tc]pertechnetate/Tc sestamibi (TcO4/sestamibi) scintigraphy and neck ultrasound obtained in the same session. One hundred and eighty-seven patients from the whole series (75 of whom were older than 65 years) with a high scan/ultrasound probability of a solitary PA, a high PA sestamibi uptake, and a normal thyroid gland were selected for MIRS. The other 79 patients were selected for traditional BNE. The intra-operative technique was based on the injection of a low dose (37 MBq) of sestamibi in the operating theatre a few minutes before the beginning of intervention and on the use of an 11 mm collimated gamma probe.

RESULTS

MIRS was successfully performed in 97.8% of all PHPT patients selected for this type of surgery and, in particular, in 100% of the subgroup (n=75) of elderly patients. MIRS required a mean operating time of 35 min and a mean hospital stay of 1.2 days; that is, approximately half of that required for traditional BNE. Moreover, local anaesthesia was successfully performed in 27 patients, 19 of whom were >65 years with concomitant invalidating diseases contraindicating general anaesthesia. No major surgical complications were recorded. Transitory hypocalcaemia was observed in 9% of cases treated with MIRS compared with 27% of patients treated with BNE.

CONCLUSION

MIRS can be accurately planned in elderly PHPT patients with a solitary PA on the basis of a TcO4/sestamibi scan and neck ultrasound. MIRS has been proven to be safe and effective in our experience, and allows a significant reduction of operating and recovery time, as well as the possibility of using local anaesthesia, especially in elderly patients with concomitant invalidating diseases.

Endoscopic parathyroidectomy

This article describes the techniques of endoscopic and endoscopic assisted parathyroidectomy, with a special emphasis on the accumulated experience as well as the advantages and drawbacks of these novel techniques.

Impact of intraoperative parathyroid hormone monitoring on the prediction of multiglandular parathyroid disease

Optimal interpretation of the results of intraoperative parathyroid hormone (IOPTH) monitoring during neck exploration for primary hyperparathyroidism (pHPT) is still controversial. The reliability of the "50% rule" in multiglandular disease (MGD) is often disputed, mostly because of competing pathophysiologic paradigms. The aim of this study was to ascertain and corroborate the ability of IOPTH monitoring to detect MGD in a practice, combining conventional and alternative parathyroidectomy techniques. This is a retrospective single institution analysis of 69 consecutive patients undergoing cervical exploration for pHPT by various approaches. The IOPTH measurements were performed after induction of anesthesia but prior to skin incision and 10 minutes after excision of the first visualized enlarged parathyroid gland. In this series, 55 patients (80%) had single adenomas, and 14 patients (20%) had MGD. In 8 of the 14 patients with MGD, IOPTH levels were obtained sequentially after removal of every enlarged gland. Of these 8 patients, 6 (75%) had a false-positive decrease (decrease below 50% of baseline value in presence of another enlarged gland) failing to predict the presence of a second enlarged gland. In 2 cases IOPTH monitoring provided a true-negative result, correctly predicting MGD. If MGD is defined by gross morphologic criteria, IOPTH monitoring fails to predict the presence of MGD reliably. However, if MGD is defined by functional criteria, the course of these patients does not seem significantly affected. The importance of these findings must be further investigated, especially with regard to the outcome of minimally invasive parathyroid procedures.

Impact of intraoperative parathyroid hormone monitoring on the prediction of multiglandular parathyroid disease

Optimal interpretation of the results of intraoperative parathyroid hormone (IOPTH) monitoring during neck exploration for primary hyperparathyroidism (pHPT) is still controversial. The reliability of the "50% rule" in multiglandular disease (MGD) is often disputed, mostly because of competing pathophysiologic paradigms. The aim of this study was to ascertain and corroborate the ability of IOPTH monitoring to detect MGD in a practice, combining conventional and alternative parathyroidectomy techniques. This is a retrospective single institution analysis of 69 consecutive patients undergoing cervical exploration for pHPT by various approaches. The IOPTH measurements were performed after induction of anesthesia but prior to skin incision and 10 minutes after excision of the first visualized enlarged parathyroid gland. In this series, 55 patients (80%) had single adenomas, and 14 patients (20%) had MGD. In 8 of the 14 patients with MGD, IOPTH levels were obtained sequentially after removal of every enlarged gland. Of these 8 patients, 6 (75%) had a false-positive decrease (decrease below 50% of baseline value in presence of another enlarged gland) failing to predict the presence of a second enlarged gland. In 2 cases IOPTH monitoring provided a true-negative result, correctly predicting MGD. If MGD is defined by gross morphologic criteria, IOPTH monitoring fails to predict the presence of MGD reliably. However, if MGD is defined by functional criteria, the course of these patients does not seem significantly affected. The importance of these findings must be further investigated, especially with regard to the outcome of minimally invasive parathyroid procedures.

Primary hyperparathyroidism

PURPOSE OF REVIEW

This contribution presents research progress concerning primary hyperparathyroidism (pHPT), and the background for recent notable changes in treatment policy.

RECENT FINDINGS

Research has clarified that most patients with pHPT require surgery due to risk for osteoporosis, renal stones, and possibly silent complications of renal impairment, cardiovascular disease, and common psychiatric disability. Genetic studies have advanced, but the cause of the disease remains unclear for most patients. Localization methods for parathyroid tumors have improved and increased the interest for less invasive operative methods with shorter hospital stays and reduced costs for the patient. It is important to delineate when this really will imply progress and to use the new diagnostic methods in discussions of appropriate treatment strategies. It has also become evident that older pHPT patients especially could benefit from medical treatment of bone mineral deficit, and they may also need vitamin D or vitamin D analogues to prevent progress of the disease.

SUMMARY

pHPT is a common disorder among postmenopausal women, in whom most commonly applied surgical treatment has proven markedly efficient. There is now increased interest to better understand possible causes of the disease and schedule the most efficient surgical and medical treatment and discuss possible prophylaxis.

Intraoperative parathyroid hormone assay and parathyroid reoperations

BACKGROUND

The purpose of this study was to determine whether intraoperative parathyroid hormone (IOPTH) assay improved results of reoperations.

METHODS

One hundred two patients with persistent/recurrent sporadic primary hyperparathyroidism underwent 108 reoperations (1996-2002). IOPTH was not used (n=58) from 1996-1998 (group 1). IOPTH was used (n=50) from 1999-2002 (group 2). Sensitivity and positive predictive value of IOPTH and its influence on surgical strategy were analyzed. A 50% decrease occurring 10 minutes after removal of parathyroid tumor was used to determine if all abnormal tissue had been removed.

RESULTS

Groups 1 (58 patients) and 2 (50 patients) were comparable except for duration of follow-up. The cure rate was 84% (group 1, 87%; group 2, 82%, P=0.7). Hypocalcemia developed in 20 patients (permanent in 2 patients). There was 1 permanent vocal cord paralysis and 1 patient died of toxic shock syndrome. IOPTH successfully predicted cure in 44 of 49 patients (sensitivity, 90%); the positive predictive value was 90%. Values for parathyroid hormone level and the ratio parathyroid hormone/calcium at day 1 were at least as accurate as IOPTH in predicting cure. IOPTH was helpful in 1 patient but misleading in 4 patients. It failed to modify intraoperative strategy in most other patients.

CONCLUSIONS

IOPTH testing was relatively reliable in patients with persistent or recurrent sporadic primary hyperparathyroidism, but the test unfortunately failed to improve the overall success rate at reoperation.

Negative preoperative localization studies are highly predictive of multiglandular disease in sporadic primary hyperparathyroidism

BACKGROUND

The development of localization studies and quick parathyroid hormone assay (QPTH) has allowed the development of focused surgery in sporadic primary hyperparathyroidism. The aim of this investigation was to determine whether localization studies select a specific population of patients.

METHODS

From 1999 to 2001, 213 patients underwent surgery for sporadic primary hyperparathyroidism. All were investigated with sestamibi scanning and ultrasonography. When at least 1 study showed a positive result (n=175), the patient underwent a video-assisted approach with QPTH. When results were negative (n=38), the patient underwent cervicotomy and exploratory procedures of all 4 parathyroid glands.

RESULTS

All patients are cured (mean follow-up, 17.8+/-10.3 months [SD]). Patients with negative preoperative study results had a high risk of multiglandular disease (12/38 patients; 31,6%), compared with patients with 1 positive study result (3/83 patients; 3.6%; P<.0001) and those with 2 concordant positive study results (0/92 patients; P<.0001).

CONCLUSION

When preoperative localization study results are negative, the patient has a high risk of multiglandular disease, and a conventional cervicotomy with identification of the 4 glands is recommended strongly. When only 1 localization study is positive, the risk of multiglandular disease justifies the use of QPTH during a focused approach. When positive localization study results are concordant, the use of QPTH is questionable during a focused approach.

Intraoperative testing for parathyroid hormone: a comprehensive review of the use of the assay and the relevant literature

OBJECTIVE

The rapid intraoperative parathyroid hormone assay is transforming the parathyroidectomy procedure. We present a review of the literature on the use of the assay as an adjunct to surgery. To our knowledge, this is the first review of the literature to encompass and compare all known primary studies of this assay in parathyroidectomy patients.

DATA SOURCES

Articles were collected by searching MEDLINE databases using relevant terminology. The references of these articles were reviewed for additional studies. Supplementary articles pertinent to the parathyroidectomy procedure, preoperative parathyroid localization studies, and intraoperative parathyroid hormone assay development also were examined.

STUDY SELECTION AND DATA EXTRACTION

One hundred sixty-five references were analyzed and categorized separately into groups.

DATA SYNTHESIS

The primary studies of intraoperative data on patients undergoing parathyroidectomy were compared when possible. Studies were analyzed by type of assay used, where performed, turnaround time, and efficiency of use. Reviews of the types of parathyroid surgery and preoperative localization were included for educational purposes.Conclusions.-The intraoperative parathyroid hormone assay is a useful adjunct to preoperative imaging and parathyroid surgery because of its unique ability to detect an occult residuum of hyperfunctioning parathyroid tissue. Use of this assay will obviate the need for frozen section in most routine cases. The test facilitates minimally invasive parathyroidectomy for single parathyroid adenomas, which, in turn, improves cost-effectiveness and cosmetic outcome. Its use in patients with known preoperative multiglandular disease is promising but requires further study.

Minimally invasive endoscopic-assisted parathyroidectomy for primary hyperparathyroidism

BACKGROUND

Minimally invasive surgery for primary hyperparathyroidism (pHPT) depends on both an accurate preoperative localization and the availability of intraoperative parathyroid hormone monitoring.

METHODS

Patients with sporadic pHPT and one unequivocally enlarged parathyroid gland on preoperative imaging underwent endoscopic-assisted parathyroidectomy. Intraoperative rapid parathyroid hormone (quick PTH) monitoring was performed, and surgical success was confirmed when there was a >50% decrease in quick PTH level 10 min after excision as compared with the baseline level at induction. The surgical outcome and the use of preoperative localization, together with the role played by quick PTH assay in enhancing the operative success, were evaluated.

RESULTS

From 1999 to 2002, 66 of 107 patients (62%) were selected for this approach. The accuracy of 99mTc-Sestamibi scintigraphy and ultrasonography was 97% and 70%, respectively. Conversion was required in four cases due to technical problems, and four additional patients failed to show a significant decline in quick PTH levels postexcision. Two patients underwent cervical exploration without the finding of any additional pathology, and another two patients had a delayed drop in quick PTH that was confirmed 30 min postexcision. All patients had a solitary adenoma and were cured of hypercalcemia during a median follow-up of 9 months.

CONCLUSIONS

Minimally invasive endoscopic-assisted parathyroidectomy can be performed expeditiously in a select group of patients based on 99mTc-Sestamibi scintigraphy. The use of quick PTH assay can ensure surgical success, but careful interpretation of the results is mandatory.