Radioguided parathyroidectomy for hyperparathyroidism in the reoperative neck

Low-dose radio-guided parathyroidectomy: A non-inferiority systematic review and meta-analysis

BACKGROUND

Performing MIRP procedure with a 20-fold less MIBI isotope dose allows lower radiation exposure risk for both patient and staff and reduce the overall cost of the procedure. The main goal of this systemic review and meta-analysis is to prove the non-inferiority of the very low dose MIRP compared to the standard dose.

METHODS

We performed a systemic review and meta-analysis of three different electronic databases - PubMed, Web of Science and google scholar. Meta-extraction was conducted in accordance with PRISMA guidelines.

RESULTS

Among 4750 studies imported for screening, only 13 studies were selected for the meta-analysis. Analyzed data from the 13 selected studies performed with low dose MIRP demonstrated a detection rate greater than 97 ​% and a success rate greater than 95 ​%, which is comparable to the cure rate required by current guidelines, as well as to data published by studies using the original high dose protocol.

CONCLUSION

Very low dose MIRP is not inferior to the high dose original MIRP and may be used in separate day protocol routinely.

Complex Primary Hyperparathyroidism: Hereditary and Recurrent Disease

Primary hyperparathyroidism can be sporadic or part of a genetic syndrome, such as MEN1 or HPT-JT. Diagnosis of hereditary HPT requires a thorough history and physical. Parathyroidectomy is curative with greater than 95% success. However, some patients have persistent or recurrent disease requiring reoperation. Reoperative parathyroidectomy is technically challenging, and localizing the pathologic gland can difficult. Patients needing reoperation should undergo evaluation by a high-volume surgeon. Care should be taken to obtain all of the preoperative workup and operative note from the initial surgery. Radioguided parathyroidectomy can be safely and effectively performed in patients with hereditary HPT or undergoing reoperative surgery.

Persistent and Recurrent Primary Hyperparathyroidism: Intraoperative Supplemental Methods, Basic Principles of Surgery, and Other Treatment Options

Reoperative parathyroid surgery is challenging even for experienced surgeons. Cure rates are lower than primary surgery. Good anatomical and embryological knowledge is important. Preoperatively, a comprehensive surgical strategy should be planned. Pre-operative imaging modalities should be used extensively to find the overlooked gland to have a possibility to perform focused parathyroid surgery to avoid possible complications. One of the important developments is the new ancillary methods to find overlooked parathyroid glands. Orthotopic and possible ectopic locations should be known well by the surgeon to increase the surgical success rate. Reoperative parathyroid surgery needs a distinctive approach compared to primary parathyroid surgery. Basic principles include the selection of the incision and route for entering the thyroid region, use of ancillary methods, and intraoperative nerve monitoring and also require a meticulous dissection. Obtaining a surgical cure is difficult and high surgical caution is needed. Post-operative complication rates are higher compared to primary parathyroid surgery. Other treatment methods and medical treatment options may be evaluated in a patient who cannot undergo surgery.

Radio-guided procedure in minimally invasive surgery for primary hyperparathyroidism

Minimally invasive parathyroidectomy, of choice in most cases of primary hyperparathyroidism, shows a high detection rate, based on precise preoperative localization by MIBI scintigraphy (SPECT/CT) and neck ultrasound. Radioguided minimally invasive parathyroidectomy is an even more effective technique, which shortens surgical times, maintains minimal incision and few complications, allows immediate verification of parathyroid adenoma removal and is especially interesting in patients with ectopic lesions or cervical surgical history. In this paper, the indications, protocols and differences between the two available radioguided parathyroid surgery procedures (MIBI and R.O.L.L.) are exposed.

Radioguided surgery in primary hyperparathyroidism: a review of the different available techniques

Parathyroidectomy has evolved over the years from bilateral neck exploration to a single gland approach using minimally invasive surgery. The precise presurgical localization of the problem gland, using functional techniques, such as double-phase scintigraphy with [^99mTc] Tc-MIBI including SPECT-CT and PET-CT with [¹⁸F]-Choline and morphological ones, such as ultrasound have played a crucial role in this paradigm's shift. Radioguided surgery techniques have also adapted and grown with new contributions known for their indication in other fields. Thus, we currently have a wide range of techniques that have been added to the minimally invasive radioguided parathyroidectomy with [^99mTc] Tc-MIBI, which was the first on the stage and for which more experience exists. Among them, in this update, we will discuss parathyroidectomy using ultrasound-guided ROLL technique as well as with the use of ¹²⁵I seeds and finally, hybrid techniques that use radiotracer and fluorescence.

Gonioprobe, an Innovative Gamma-probe to Guide Parathyroid Radioguided Surgery: First Clinical Experiences with Navigator and Lock-ontarget Functions

BACKGROUND

Radioguided surgery represents a validated technique for the detection and the excision of abnormal parathyroid glands responsible for primary hyperparathyroidism (PHPT). To date little attention has been paid as to how the characteristics of gamma-probes can influence surgical procedure and time, thus having an impact on postoperative morbidity, hospitalization and costs.

METHODS

We designed a new prototype of gamma-probe, the Gonioprobe, and tested its clinical utility in the operating room. Gonioprobe, thanks to its 5 scintillating independent crystals, performs the dual function of Navigator and Lock-on-target. These characteristics allow the immediate guidance of the surgeon's hand towards the source with very high precision, and with a much higher spatial resolution than commercial probes. Gonioprobe was used during intervention to detect abnormal parathyroid tissue, and to ensure no radioactivity in surgery bed after adenoma removal.

RESULTS

We tested our gamma-probe on parathyroid adenomas particularly difficult to identify at a visual inspection due to anatomy modifications from previous neck surgery and/or characterized by uncommon localization. Moreover, parathyroid adenomas were hardly removable due to the proximity to the esophagus, neck vessels and/or recurrent laryngeal nerve (RLN). An intraoperative nerve monitoring system was used to protect the recurrent laryngeal nerve from injuries. Parathyroid hormone (PTH) assay and frozen biopsy confirmed the successful excision of the adenomas.

CONCLUSION

The intraoperative use of the innovative Gonioprobe along with the nerve monitoring system allowed an accurate and safe removal of parathyroid adenomas and offered a significant advantage by reducing surgical time and postoperative complications, as well as hospitalization and costs.

Re-operative Parathyroidectomy in Patients With Mild Primary Hyperparathyroidism

BACKGROUND

Surgery is the definitive management of primary hyperparathyroidism and the only curative therapy. However, many surgeons are hesitant to operate on individuals with mild primary hyperparathyroidism, with an even greater reluctance to operate on those who underwent a previous parathyroidectomy. We hypothesize that patients with mild primary hyperparathyroidism who undergo a re-operation have equivalent outcomes compared with those who undergo a first-time (FT) operation.

METHODS

We reviewed a prospective database of 459 patients with mild primary hyperparathyroidism who underwent surgery by one endocrine surgeon. Of these patients, 59 had a re-operative (RE-OP) parathyroid surgery. We compared these patients to those with mild primary hyperparathyroidism who had FT surgery (n = 400) using either the Pearson chi-square, Fisher's exact test, or Student's t-test where appropriate.

RESULTS

The mean age of our cohort was 60 ± 14 y, with 86% females. Patients in the RE-OP group had similar preoperative calcium and parathyroid hormone levels compared with those in the FT group. Most patients who underwent a RE-OP surgery had four gland hyperplasia on pathology (49.2%). Patients in the RE-OP and FT groups both had high and similar cure rates (100% versus 99.8%, P = 0.70). RE-OP patients had a higher rate of recurrent hyperparathyroidism (10.3% versus 3.3%, P = 0.025).

CONCLUSIONS

In patients with mild primary hyperparathyroidism, those who undergo RE-OP parathyroidectomy have a high cure rate that is similar to FT surgery. Therefore, we recommend that these patients with recurrence of mild hyperparathyroid disease be considered for parathyroidectomy.

Intraoperative Adjunct Methods for Localization in Primary Hyperparathyroidism

Primary hyperparathyroidism (pHPT) is a frequently seen endocrine disease, and its main treatment is surgery. In the majority of pHPT, the disease involves only a single gland, and the majority of the pathological glands can be determined by preoperative localization methods.In addition to preoperative localization studies in parathyroidectomy, the use of adjunct methods to improve intraoperative localization in order to increase success of surgery is becoming widespread. These methods include different approaches, mainly intraoperative parathyroid hormone (PTH) measurement, followed by intraoperative gamma probe application, intraoperative ultrasonography, parathyroid imaging with methylene blue, and frozen section examination. Recently, especially promising new imaging methods have been described in the literature with various optical technologies to increase the localization of the parathyroid glands and to evaluate their viability. These methods include parathyroid imaging with autofluorescence, indocyanine green imaging with autofluorescence, autofluorescence imaging with methylene blue, autofluorescence imaging with 5-aminolevulinic acid, optical coherence tomography, laser speckle contrast imaging, dynamic optical contrast imaging, and Raman spectroscopy. Currently, minimally invasive parathyroidectomy has become the standard treatment for selected pHPT patients with the aid of preoperative imaging and intraoperative auxiliary methods . The aim of the present study was to evaluate the routinely used new promising intraoperative adjunct methods in pHPT.

Surgical Treatment of Primary Hyperparathyroidism: Which Therapy to Whom?

Primary hyperparathyroidism (pHPT) is characterized by an increase in the levels of PTH and Ca, or one of these (Ca, PTH) as a result of a dysregulation of calcium (Ca) metabolism due to inappropriate excess parathyroid hormone (PTH) autonomously produced from one or more than one parathyroid glands. Ninety to 95% of pHPT is a sporadic type, which is not associated with the familial history and other endocrine organ tumors, and 5-10% of it is hereditary. While 80-85% of pHPT arises from a single parathyroid adenoma, 4-5% is caused by a double adenoma, 10-15% by multigland hyperplasia and less than 1% by parathyroid cancer. The diagnosis of pHPT is reached biochemically. The only curative treatment of pHPT is surgery. The choice of surgery in pHPT may vary depending on whether the patient has hereditary HPT or thyroid disease requiring surgical treatment, preoperative localization studies and the findings in these studies, the possibilities of using intraoperative PTH and the preference of the surgeon. The preoperatively determined surgical strategy can be revised according to intraoperative findings in case of need to achieve excellent results. The two main approaches in the surgical treatment of pHPT are BNE (bilateral neck exploration) and MIP (minimal invasive parathyroidectomy). Although BNE is a consistently valid option that has excellent results in the surgical treatment of pHPT and is considered the gold standard, MIP is the ideal approach in selected patients with clinically and radiologically considered a single-gland disease. Negative imaging is not a contraindication for parathyroid surgery and is not a criterion for the presence or absence of surgical indication. Although both methods are safe and effective in the surgical treatment of sporadic pHPT, there is still controversy regarding the effectiveness of both methods. Surgical intervention should establish the risk-benefit balance well, minimize the risk of persistent and recurrent disease and provide the highest cure rate without increasing the risk of complications. Complication rates are higher in the secondary surgery, thus in secondary procedures, selective surgery should be performed under guidance of an imaging modality. The surgical strategy should be determined to achieve maximum cure with minimum dissection and minimal morbidity. In this study, we aimed to determine the type of surgical treatment and pHPT patients suitable for the surgical treatment.

Radio-guided miniinvasive surgery of solitary parathyroid adenoma as a cause of primary hyperparathyroidism

The function of parathyroid gland is affected by a wide spectrum of diseases, among them primary hyperparathyroidism is the most common. In about 85% of the patients a solitary parathyroid adenoma is the cause of the hyperparathyroidism. Surgical removal of pathologically changed gland is a treatment of choice, usually performed by miniinvasive radio-guided parathyroidectomy.

In this article the authors review current knowledge, research state, and present some cases of this operation at the Clinic of Otorhinolaryngology and Head and Neck Surgery, Jessenius Faculty of Medicine, Comenius University and University Hospital Martin, Martin, Slovakia.

Recurrent primary hyperparathyroidism due to Type 1 parathyromatosis

Parathyromatosis is a rare condition consisting of multiple nodules of benign hyperfunctioning parathyroid tissue scattered throughout the neck and superior mediastinum. As a potential cause of recurrent or persistent hyperparathyroidism, parathyromatosis is a challenging condition to diagnose and treat. The optimal evaluation and management of patients with parathyromatosis is not well established. The reported case involves a patient who was initially diagnosed with primary hyperparathyroidism. The diagnosis of Type 1 parathyromatosis was made after the patient developed recurrent hyperparathyroidism with hypercalcemia and osteoporosis 17 years after the initial operation and underwent two additional operations. The majority of parathyromatosis cases are diagnosed in the setting of secondary hyperparathyroidism. Consensus regarding the preoperative diagnosis and evaluation is lacking due to the paucity of cases of this rare clinical entity. Management involves complete surgical extirpation of all identifiable rests of parathyroid tissue. Intra-operative parathyroid hormone level monitoring and frozen section examination are excellent tools that could increase the rates of initial operative success. Despite this, long-term disease remission is rare, and medical therapy, including calcimimetics and bisphosphonates, may be required for postoperative or non-operative management.

Long-term effectiveness of localization studies and intraoperative parathormone monitoring in patients undergoing reoperative parathyroidectomy for persistent or recurrent hyperparathyroidism

BACKGROUND

Reoperative parathyroidectomy (RPTX) for persistent or recurrent hyperparathyroidism is associated with a high rate of operative failure. The long-term effectiveness of RPTX using localization studies and intraoperative parathormone monitoring (IPM) was examined.

METHODS

Retrospective analysis of prospectively collected data from patients undergoing targeted RPTX with IPM for persistent or recurrent hyperparathyroidism was performed. Persistent hyperparathyroidism was defined as elevated calcium and parathormone (PTH) levels above normal range less than 6 months after parathyroidectomy. Recurrent hyperparathyroidism was defined as elevated calcium and PTH levels greater than 6 months after successful parathyroidectomy. Sensitivity and positive predictive value (PPV) for sestamibi, surgeon-performed ultrasound, intraoperative PTH dynamics, and surgical outcomes were evaluated.

RESULTS

Of the 1,064 patients, 69 patients underwent 72 RPTXs with localizing studies and IPM. Sestamibi (n = 69) had a sensitivity of 74% and a PPV of 83%, whereas surgeon-performed ultrasound (n = 38) had a sensitivity of 55% and a PPV of 76%. IPM had a sensitivity of 100% and a PPV of 98%. An intraoperative PTH drop greater than or equal to 50% was predictive of operative success (P < .01). Overall, operative success and recurrence were 94% and 1.4%, with a mean patient follow-up of 59 ± 12.8 months.

CONCLUSION

RPTX can be performed in a targeted approach using preoperative localization studies and IPM, leading to a low rate of complications and a high rate of long-term operative success.

Reoperations for persistent or recurrent primary hyperparathyroidism: results of a retrospective cohort study at a tertiary referral center

BACKGROUND

Parathyroid reoperations are challenging and achieving a cure requires multidisciplinary treatment team cooperation. The aims of this study were to summarize our experience in revision surgery for persistent (pHPT) or recurrent primary hyperparathyroidism (rHPT) and to explore factors underlying failure to cure at initial surgery.

MATERIAL AND METHODS

This was a retrospective cohort study of patients who underwent reoperations for pHPT or rHPT at a tertiary referral center. The database of parathyroid surgery was searched for eligible patients (treated in the years 2000-2012). The primary outcome was the cure rate. All the patients were followed-up for at least 12 months postoperatively. Factors underlying failure to cure at initial surgery were reviewed based on hospital records.

RESULTS

The study group comprised 88 patients (69 women, 19 men) operated on for persistent (n=57) or recurrent disease (n=31), who underwent 98 reoperations, including 26 (2.4%) patients first operated on at our institution, and 72 (81.8%) patients operated on elsewhere, but referred for revision surgery. A long-term cure was achieved in 83/88 patients (94.3%). The mean post-reoperation follow-up was 91.7 (12-176) months. Missed hyperfunctioning parathyroid gland was found on reoperation in eutopic position in 49 (55.5%) patients, and in ectopic position in 39 (44.3%) patients, including 20 (22.7%) cases of cervical ectopy and 19 (21.6%) cases of mediastinal ectopy.

CONCLUSIONS

Multidisciplinary treatment team cooperation at a tertiary referral center, consisting of an accurate preoperative localization, expertise in parathyroid re-explorations, and correct use of intraoperative adjuncts, contribute to the high success rate of parathyroid reoperations.

The efficacy of low and high dose (99m)Tc-MIBI protocols for intraoperative identification of hyperplastic parathyroid glands in secondary hyperparathyroidism

OBJECTIVE

The aim of this study was to compare the efficacy of low- and high-dose (99m)Tc-MIBI protocols for intraoperative identification of hyperplastic parathyroid glands via gamma probe in secondary hyperparathyroidism.

MATERIAL AND METHODS

This retrospective study was conducted using a prospective database of 59 patients who had undergone radioguided subtotal parathyroidectomy between 2004-2012. The patients were studied in 2 groups. Group 1 (n=31) received 37 MBq (99m)Tc-MIBI intravenously in the surgical room approximately 10 min before the beginning of the intervention and surgery was performed under gamma probe guidance. Group 2 (n=28) received 555 MBq (99m)Tc- MIBI intravenously 2h before surgery, which was also performed under gamma probe guidance. Intraoperative gamma probe findings, laboratory findings, and histopathological findings were evaluated together.

RESULTS

Using acceptance of the histopathological findings as gold standard, sensitivity and specificity of intraoperative gamma probe for identifying hyperplastic parathyroid glands was 98% and 100%, respectively, in both groups.

CONCLUSIONS

In the light of these findings, it is concluded that the low-dose (99m)Tc-MIBI protocol might be preferable for intraoperative identification of hyperplastic parathyroid glands in secondary hyperparathyroidism patients because it was observed to be as effective as the high-dose (99m)Tc-MIBI protocol. Furthermore, the low-dose protocol does not have the disadvantages that are associated with the high-dose protocol.

Surgical Targeting of Recurrent Thyroid Cancer Using a Novel Mixture of 99m-Technetium Macroaggregated Albumin and Indocyanine Green

Background. Precise targeting has played a pivotal role in the success of surgery for recurrent differentiated thyroid cancers (DTCs). To improve on current targeting methods, we developed a novel technique using 99mTc-macroaggregated human serum albumin and indocyanine green (TIGMA), with which surgeons effectively target lesions in real time by radiofluorescence dual guidance. Methods. Seven patients with 10 recurrent DTC lesions were retrospectively enrolled in the study. Prior to the operation, we injected TIGMA into the target lesion under the guidance of ultrasonography. Resection was concurrently monitored using a gamma probe and a specially designed near infrared fluorescence camera. Outcomes were evaluated using imaging, surgical, and pathological records. Results. In all enrolled cases, both injection of TIGMA and radiofluorescence dual guidance were well tolerated and easy to implement. The technical success rates were 100%, confirmed by final pathological examination, postoperative ultrasonography, and I-131 scan clearance. Complications such as temporary postoperative neck pain (n = 2) were minimal. Conclusions. TIGMA using radiofluorescence dual guidance facilitated the precise targeting of recurrent lesions. The entire procedure was feasible, safe, and successful. This method would help enhance surgical outcomes for recurrent DTCs.

Nonadenomatous nonencapsulated thymic parathyroid tissue concomitant with primary hyperparathyroidism due to ectopic parathyroid adenoma

Primary hyperparathyroidism due to ectopic parathyroid adenoma is not infrequent. Primary hyperparathyroidism caused by unusual thymic nonadenomatous nonencapsulated parathyroid tissue has been reported before. Both can cause unsuccessful neck explorations. Here we presented for the first time a patient with hyperparathyroidism due to ectopic parathyroid adenoma concomitant to the presence of thymic nonadenomatous nonencapsulated parathyroid tissue.

Radioguided parathyroidectomy effective in pediatric patients

BACKGROUND

Radioguided parathyroidectomy (RGP) has been shown to be effective in adult patients with hyperparathyroidism (HPT), but the utility of RGP in pediatric patients has not been systematically examined. It is not known if adult criteria for radioactive counts can accurately detect hyperfunctioning parathyroid glands in pediatric patients. The purpose of our study was to determine the utility of RGP in children with primary HPT.

MATERIALS AND METHODS

A retrospective review of our prospectively maintained single-institution database for patients who underwent a RGP for primary HPT identified 1694 adult and 19 pediatric patients aged 19 y or younger. From the adult population, we selected a control group matched three to one for gland weight and gender and compared pre- and postoperative laboratory values, surgical findings, pathology, and radioguidance values between the control and the pediatric groups.

RESULTS

Excised glands from pediatric patients were smaller than those in the total adult population (437 ± 60 mg versus 718 ± 31 mg, P = 0.0004). When controlled for gland weight, ex vivo counts as a percentage of background were lower in the pediatric group (51% ± 5% versus 91% ± 11%, P = 0.04). However, ex vivo radionuclide counts >20% of the background were found in 100% of pediatric patients and 95% of the adult-matched control group.

CONCLUSIONS

All pediatric patients met the adult detection criteria for parathyroid tissue removal when a RGP was performed, and 100% cure was achieved. We conclude that RGP is a useful treatment option for pediatric patients with primary HPT.

Influence of surgical volume on operative failures for hyperparathyroidism

Hyperparathyroidism is a disease that is often seen in the United States. Patients may present with a wide variety of symptoms affecting multiple organs, but frequently, they are found to be hyperparathyroid on a routine blood examination. Although these patients may be asymptomatic, new consensus guidelines exist for when they should undergo surgery, and several studies have shown multiple benefits from operative intervention. Surgical cure rates can be greater than 95%, but if the initial surgery is unsuccessful, the cure rate becomes 80%. In the hands of experienced surgeons, both initial cure rates and those for reoperations are much higher, illustrating that the surgical volume does affect failure in parathyroid surgery.

Intraoperative adjuncts for parathyroid surgery

In recent years, parathyroid surgery has evolved from traditional bilateral neck exploration to minimal invasive parathyroidectomy. This trend became possible due to preoperative localization imaging that guides the surgeon in the search for a parathyroid adenoma. Intraoperative adjuncts are complementary to preoperative localization and assist in localizing parathyroid glands, confirming parathyroid tissue and establishing a cure. Institutions and surgeons utilize different intraoperative adjuncts in different protocols with varying results. The purpose of this article is to review the available intraoperative adjuncts to parathyroid surgery and critically evaluate their utility, accuracy and their added value to the surgeon.

Operative failures after parathyroidectomy for hyperparathyroidism: the influence of surgical volume

OBJECTIVE

To determine whether surgical volume influences the cause of operative failures after parathyroidectomy for hyperparathyroidism.

SUMMARY AND BACKGROUND DATA

The surgical success rate for hyperparathyroidism from high-volume centers exceeds 95%, but some patients have unsuccessful parathyroidectomies. Although operative failure can be due to hyperfunctioning parathyroid glands in ectopic locations, less experienced surgeons may be more likely to miss an abnormal parathyroid in normal anatomic locations, which we describe as "preventable operative failure."

METHODS

We used 2 prospective databases containing over 2000 consecutive patients who underwent parathyroidectomy. We identified 159 patients with persistent/recurrent hyperparathyroidism subsequently cured with additional surgery. The initially failed operations were classified as being performed at high- (>50 cases/yr) or low-volume (<50 cases/yr) hospitals. Hospital volume was obtained from a Wisconsin state database of 89 hospitals, which reported 6336 parathyroid operations during the same decade.

RESULTS

Patients who initially failed their operation performed at the high- or low-volume centers were similar with regard to age, laboratory values, gender, and parathyroid weights. Despite a higher incidence of multigland disease (which increases the likelihood of operative failure) in the high-volume group, patients in the low-volume group were more likely to have a missed parathyroid gland in a normal anatomic location (89% vs. 13%, P < 0.0001), and thus a higher proportion of preventable operative failures.

CONCLUSIONS

Surgical volume influences the failure pattern after parathyroidectomy for hyperparathyroidism. Preventable operative failures are more common in low-volume centers.