Parathyroid Adenomas In Patients Research Articles

Cost-effectiveness of one-stop-shop [18F]Fluorocholine PET/CT to localise parathyroid adenomas in patients suffering from primary hyperparathyroidism.

We conducted a cost-effectiveness analysis in which we compared a preoperative [18F]Fluorocholine PET/CT-based one-stop-shop imaging strategy with current best practice in which [18F]Fluorocholine PET/CT is only recommended after negative or inconclusive [99mTc]Tc-methoxy isobutyl isonitrile SPECT/CT for patients suffering from primary hyperparathyroidism. We investigated whether the one-stop-shop strategy performs as well as current best practice but at lower costs. We developed a cohort-level state transition model to evaluate both imaging strategies respecting an intraoperative parathyroid hormone monitored treatment setting as well as a traditional treatment setting. The model reflects patients' hospital journeys after biochemically diagnosed primary hyperparathyroidism. A cycle length of twelve months and a lifetime horizon were used. We conducted probabilistic analyses simulating 50,000 cohorts to assess joint parameter uncertainty. The incremental net monetary benefit and cost for each quality-adjusted life year were estimated. Furthermore, threshold analyses regarding the tariff of [18F]Fluorocholine PET/CT and the sensitivity of [99mTc]Tc-methoxy isobutyl isonitrile SPECT/CT were performed. The simulated long-term health effects and costs were similar for both imaging strategies. Accordingly, there was no incremental net monetary benefit and the one-stop-shop strategy did not result in lower costs. These results applied to both treatment settings. The threshold analysis indicated that a tariff of €885 for [18F]Fluorocholine PET/CT was required to be cost-effective compared to current best practice. Both preoperative imaging strategies can be used interchangeably. Daily clinical practice grounds such as available local resources and patient preferences should inform policy-making on whether a hospital should implement the one-stop-shop imaging strategy.

Ultrasonographic Detective Flow Imaging for Evaluating Parathyroid Adenoma in Patients with Primary Hyperparathyroidism.

Detective flow imaging (DFI) is a new imaging technology that displays low-velocity blood flow, which is difficult to visualize on conventional color Doppler ultrasonography (CDU). In this study, we compared the usefulness of DFI with that of CDU and methoxy-isobutyl-isonitrile (MIBI) scintigraphy for detecting parathyroid adenoma (PA) in patients with primary hyperparathyroidism (PHPT). From March 2021 to March 2023, 87 PHPT patients underwent surgery, and 66 had a single PA. We performed preoperative conventional ultrasonography with CDU, MIBI scintigraphy, and DFI for 42 patients (5 males and 37 females; mean age: 61.6 ± 15.4 years). MIBI scintigraphy detected PA in 85.7% (36/42) patients, and both CDU and DFI detected PA in all patients. The rates of vascularity in PA detected by CDU and DFI were 71.4% (30/42) and 85.7% (36/42), respectively. Vascularity was detected by DFI in 6 patients who were negative for vascularity on MIBI scintigraphy. Furthermore, DFI detected blood supply in 6 of the 12 patients with undetectable blood supply on CDU. Fisher's exact test revealed that high or low blood flow, as determined by DFI, was significantly associated with detection of feeding vessels in PA by CDU (P < 0.001). DFI was useful for preoperative detection of PA blood flow.

Preoperative Lateralization and Diagnostic Value of Selective Bilateral Internal Jugular Venous Sampling in Primary Hyperparathyroidism: Single-Center Experience.

Background and Objectives: Primary hyperparathyroidism (pHPT) is a common endocrine disorder caused by excessive production of parathyroid hormone (PTH) leading to elevated calcium levels. Diagnosis is primarily based on biochemical evaluation, and surgery is the curative treatment. Imaging techniques like ultrasound and Tc-99m Sestamibi scintigraphy are used for localization, but selective Internal Jugular Venous (SVS) becomes valuable in cases of inconclusive or conflicting results. This study evaluated the diagnostic efficacy of SVS for localizing parathyroid adenomas in cases where non-invasive radiological diagnostic methods yielded inconclusive results or negative findings despite clinical symptoms suggestive of pHPT. Materials and Methods: In this retrospective study, a total of 28 patients diagnosed with pHPT underwent SVS at a tertiary center known for receiving referrals from 2017 to 2022. The diagnoses were confirmed through biochemical analysis. The SVS results in 22 patients were compared with non-invasive imaging methods, including ultrasound, scintigraphy, and computed tomography with/without contrast material. SVS was indicated when at least two non-invasive diagnostic procedures failed to clearly localize the parathyroid glands or provided ambiguous results. Results: SVS demonstrated higher sensitivity for localizing parathyroid adenomas compared to non-invasive imaging methods, accurately lateralizing the adenoma in 68.18% of cases. Among the SVS findings, 31.8% of patients had negative results, with 9.1% not having clinically proven parathyroid adenoma, while 22.7% had false negative SVS findings but were later confirmed to have adenoma during surgery. Ultrasound correctly identified the location in 45.45% of cases, CT in 27.27%, and scintigraphy in 40.9%. Conclusions: SVS is a valuable diagnostic tool for accurately localizing parathyroid adenomas in patients with inconclusive non-invasive imaging results. It aids in targeted surgical interventions, contributing to improved management and treatment outcomes in primary hyperparathyroidism.

Differences Between Atypical Parathyroid Tumors and Parathyroid Adenomas in Patients with Primary Hyperparathyroidism

Differences Between Atypical Parathyroid Tumors and Parathyroid Adenomas in Patients with Primary Hyperparathyroidism

Parathyroid fine-needle aspiration with parathyroid hormone washout as a preoperative localisation of parathyroid adenoma-A retrospective study.

The use of parathyroid lesion aspiration in preoperative adenoma localisation is controversial. Concerns have been raised regarding both immediate safety (hematoma, infection, alterations on a subsequent histologic preparate) and long-term safety (seeding). We aimed to evaluate the short- and long-term safety, and the efficacy, of parathyroid fine-needle aspiration with parathyroid hormone washout as a localisation modality of parathyroid adenoma in patients with primary hyperparathyroidism. A retrospective study. The sample comprised 29 patients with primary hyperparathyroidism who underwent minimally invasive parathyroidectomy at a tertiary referral centre, following localisation with parathyroid hormone washout. We reviewed all parathyroid hormone washout procedures performed during 2011-2021. Clinical, biochemical, and imaging information; and cytology, surgery, and pathology reports were extracted from electronic medical records. Parathyroid hormone levels from the needle wash were 2.1-112.5 times the upper limit of the serum norm. Other than mild neck discomfort, no immediate procedure complications were documented. Fibrotic changes and necrosis were reported in two patients, with no effect on the final pathologic diagnosis or surgery course. No long-term complications (seeding, or parathyromatosis) were found. A total of 26 (90%) patients who were operated following a positive parathyroid hormone washout result were normocalcemic at the end of a mean 38.1-month follow-up period. Parathyroid fine-needle aspiration with parathyroid hormone washout was accurate. Immediate, surgical, or delayed complications were not demonstrated in our series. This approach might be considered for selected patients.

Submandibular Ectopic Parathyroid Adenoma: A Case Report.

Primary hyperparathyroidism (PHPT) is a common endocrine disorder characterized by hypercalcemia and elevated or abnormally normal parathyroid hormone (PTH) levels, due to excessive secretion of PTH by 1 or more parathyroid glands. In this report, we discuss the diagnostic and therapeutic challenges posed by ectopic parathyroid adenomas, a rare but atypical presentation of PHPT. We present the case of a 36-year-old female with PHPT due to an ectopic parathyroid adenoma located in the submandibular region. The patient presented with bone pain and was initially evaluated with routine imaging studies, which were negative. [18F] F-choline positron emission tomography (PET)/Computed tomography revealed the ectopic adenoma, leading to successful surgical management. Ectopic parathyroid adenomas are rare but can occur in various locations, and functional imaging modalities such as choline PET can aid in their detection. Surgical resection remains the definitive treatment for parathyroid adenomas, with intraoperative PTH monitoring guiding the extent of resection. Proper evaluation and management of PHPT is essential to avoid significant morbidity. Our case adds to the growing body of literature on the importance of considering ectopic locations of parathyroid adenomas in patients with PHPT.

AIUM Practice Parameter for the Performance and Interpretation of Diagnostic Ultrasound of the Thyroid and Extracranial Head and Neck.

AIUM Practice Parameter for the Performance and Interpretation of Diagnostic Ultrasound of the Thyroid and Extracranial Head and Neck.

Clinical characteristics of primary parathyroid adenoma and its relationship with coexisting papillary thyroid carcinoma: a clinical retrospective study.

Parathyroid adenoma (PA) is a common but relatively poorly understood endocrine tumor. A significant number of PA patients also have papillary thyroid carcinoma (PTC). The clinicopathological characteristics of PA and its relationship with PTC need further study. The clinical data of 99 PA patients were reviewed and the clinicopathologic features of PA were analyzed. PTC occurred in 22 PA patients. The clinicopathologic features of 22 patients with PA + PTC and 77 patients with PA alone were compared. According to age, gender and thyroid surgery methods, 22 PA + PTC patients were matched with 1,123 patients with PTC alone during the same period. The pathological characteristics of the two groups of patients were compared. All data analysis was performed using SPSS23.0, variables were compared by t-test, chi square test or Mann Whitney U-test as appropriate. Ninety-nine PA patients (21 males, 78 females) with a median age of 51 [10-80] years were included. The preoperative parathyroid hormone (PTH) (P=0.007) and preoperative blood calcium (P=0.036) of male patients were higher than those of female patients, and the proportion of asymptomatic patients (P=0.008) and postoperative PTH level (P=0.013) were lower. The preoperative PTH level (P=0.002), preoperative blood calcium level (P=0.004), preoperative alkaline phosphatase (ALP) level (P=0.018) and postoperative PTH levels (P=0.023) in PA + PTC group were lower than those in PA group. The asymptomatic rate was higher in PTC + PA group than that in PA group (P<0.001). There was no statistical difference between PA + PTC group and PTC group in multifocal tumor, capsule invasion, lymph node metastasis (P>0.05). The lymph node metastasis rate in PA + PTC group (9/215) was significantly lower than that in PTC group (37/337) (P=0.005). PA exhibited the following characteristics: occurred in all age groups; more common in women but more severe in men; more located in the lower pole. The coexistence of PTC and PA did not promote the progression of PA, nor did it increase the aggressiveness of PTC. Conversely, their co-existence may lead to early diagnosis of the disease. PA patients (22.2%) also have PTC, so surgeons should pay attention to thyroid disease to prevent the need for reoperation.

Efficacy of surgeon performed intraoperative ultrasound scan for localisation of parathyroid adenomas in patients with primary hyperparathyroidism.

In the UK, guidance recommends ultrasound scanning alone or in combination with sestamibi scintigraphy to guide surgery in patients with primary hyperparathyroidism. If an adenoma is localised on imaging, this can facilitate targeted or minimally invasive surgery. Surgeon-performed ultrasound scan on the operating table benefits from being performed on an anaesthetised patient with optimal positioning. The aim of this study was to investigate the efficacy of intra-operative, blinded, surgeon-performed ultrasound scan in localisation of parathyroid adenomas. Prospective data were collected on consecutive patients undergoing surgery for primary hyperparathyroidism at a single tertiary centre from November 2019 to June 2021. Patients underwent blinded, surgeon-performed ultrasound scan under general anaesthesia immediately prior to surgery. Localisation results from pre-operative imaging and surgeon-performed ultrasound scan were then compared with the intra-operative findings. Forty-nine patients underwent surgery and were found to have single-gland disease. Sestamibi scintigraphy, radiologist-performed ultrasound scan and surgeon-performed ultrasound scan had sensitivities of 59.4, 43.75 and 73.8 per cent, respectively. Surgeon-performed ultrasound scan had a statistically significantly increased sensitivity compared with radiologist-performed ultrasound (p < 0.05). Intra-operative, surgeon-performed ultrasound scan is effective in localising parathyroid adenomas and may be a useful adjunct to facilitate minimally invasive parathyroid surgery.

Preoperative Location Of Parathyroid Adenomas In Primary Hyperparathyroidism: The Role of Cervical Doppler Ultrasound.

Parathyroid adenoma is the most frequent cause of primary hyperparathyroidism. In recent years, the preoperative location of parathyroid adenomas allowed minimally invasive surgical techniques that have become preferred over the traditional bilateral neck exploration. The more recent guidelines on this subject highlight the role of nuclear medicine imaging tests. The aim of this study was to review the current role of Doppler ultrasound (US) in assessing the preoperative location of parathyroid adenomas in patients with primary hyperparathyroidism. Retrospective study based on data from patients with primary hyperparathyroidism that underwent parathyroidectomy between January 2013 and January 2022 at the Centro Hospitalar Universitário Lisboa Central. Statistical analysis was performed with IBM SPSS Statistics, version 26.0.0.0®. Parathyroidectomy was performed in 171 patients (77.8% females) with primary hyperparathyroidism. Cervical Doppler ultrasound was the most performed test (64.3%, n = 110) for preoperative location and detected a suspicious lesion in 98 patients (89.1%). The preoperative location of the parathyroid adenomas was assessed through the Doppler ultrasound and was compared with the surgical reports and histological findings; a correct identification was made in 76 patients (77.6%). Doppler ultrasound slightly underestimated the mean adenoma size (18.1 ± 7.7 mm preoperative versus 22 ± 8.4 mm postoperative). Calcium, parathyroid hormone levels, adenoma size and concomitant presence of thyroid nodules did not affect the accuracy of Doppler ultrasound. Doppler ultrasound showed high diagnostic accuracy even in patients with nodular thyroid disease regardless of calcium and parathyroid hormone levels and adenoma size. Furthermore, its safety, affordability and availability should favor its use as first line test in primary hyperparathyroidism to assess the preoperative location of parathyroid adenomas.

Differences between atypical parathyroid adenomas and parathyroid adenomas in patients with primary hyperparathyroidism

Differences between atypical parathyroid adenomas and parathyroid adenomas in patients with primary hyperparathyroidism

Parathyroid venous sampling for the preoperative localisation of parathyroid adenoma in patients with primary hyperparathyroidism

Preoperative localisation studies are essential for parathyroidectomy in patients with primary hyperparathyroidism. If the location of abnormal parathyroid glands cannot be identified through non-invasive studies, parathyroid venous sampling (PVS) may be employed. In this study, we evaluated the utility of preoperative PVS in parathyroid surgery. Patients with primary hyperparathyroidism who underwent preoperative PVS at Severance Hospital between January 2015 and June 2020 were identified. Patients for whom the results of non-invasive imaging studies were inconsistent or negative underwent PVS. The results of PVS were compared with operative findings and pathologic results. For 14 patients, the results of preoperative ultrasonography and 99mTc-sestamibi single-photon emission computed tomography (SPECT) were negative; for 20 patients, either the result of only one test was positive, or the results of the two tests were inconsistent. With respect to the lateralisation of diseased adenoma, the results of PVS and pathological examination were inconsistent only for one patient in either group (total: 2/34 patients). This study showed that PVS could be used effectively for preoperative localisation in patients with primary hyperparathyroidism in whom the location of diseased parathyroid glands cannot be determined through non-invasive image studies.

Efficacy of surgeon performed ultrasound scan in localization of parathyroid adenomas in patients with primary hyperparathyroidism

Abstract Introduction The success of minimally invasive parathyroid surgery is largely based on accurate preoperative localization of parathyroid adenomas. In the U.K, NICE guidance recommends either ultrasound scanning alone or combined with sestamibi scintigraphy to help guide surgery. In the recent past, surgeon performed ultrasound (SUS) has been adopted in North America and Australia for preoperative localization with a sensitivity of 63–91%. This was equivalent or superior to radiology performed ultrasound (RUS). In comparison, data from the U.K for surgeon performed imaging is sparse. In this study, we investigate the efficacy of surgeon performed ultrasound in localization of parathyroid disease and discuss its cost benefits. Methods This is a prospective study with data collected from November 2019 to June 2021. All patients had primary hyperparathyroidism and underwent either MIBI, radiology performed ultrasound or both. A single experienced surgeon performed ultrasound on all patients under general anaesthesia. The intraoperative findings were used to determine the accuracy of all imaging techniques. Results A total of 46 patients underwent surgery and were found to have single gland disease. The categories were: Double imaging (n=17), MIBI (n=34), RUS (n=22), SUS(n=46), no imaging (n=9). MIBI, radiology performed ultrasound and surgeon performed ultrasound had sensitivities of 58%, 55% and 81% respectively. 8 patients had ectopic glands and were not included in the sensitivity analysis of ultrasound scans. Conclusion Surgeon performed ultrasound by an experienced provider is effective in localizing parathyroid adenomas and guides minimally invasive surgery. It could significantly reduce costs associated with outpatient radiology performed ultrasound scanning

Deep learning-based detection of parathyroid adenoma by 99mTc-MIBI scintigraphy in patients with primary hyperparathyroidism.

It is important to detect parathyroid adenomas by parathyroid scintigraphy with 99m-technetium sestamibi (99mTc-MIBI) before surgery. This study aimed to develop and validate deep learning (DL)-based models to detect parathyroid adenoma in patients with primary hyperparathyroidism, from parathyroid scintigrams with 99mTc-MIBI. DL-based models for detecting parathyroid adenoma in early- and late-phase parathyroid scintigrams were, respectively, developed and evaluated. The training dataset used to train the models was collected from 192 patients (165 adenoma cases, mean age: 64years ± 13, 145 women) and the validation dataset used to tune the models was collected from 45 patients (30 adenoma cases, mean age: 67years ± 12, 37 women). The images were collected from patients who were pathologically diagnosed with parathyroid adenomas or in whom no lesions could be detected by either parathyroid scintigraphy or ultrasonography at our institution from June 2010 to March 2019. The models were tested on a dataset collected from 44 patients (30 adenoma cases, mean age: 67years ± 12, 38 women) who took scintigraphy from April 2019 to March 2020. The models' lesion-based sensitivity and mean false positive indications per image (mFPI) were assessed with the test dataset. The sensitivity was 82% [95% confidence interval 72-92%] with mFPI of 0.44 for the scintigrams of the early-phase model and 83% [73-92%] with mFPI of 0.31 for the scintigrams of the delayed-phase model in the test dataset, respectively. The DL-based models were able to detect parathyroid adenomas with a high sensitivity using parathyroid scintigraphy with 99m-technetium sestamibi.

Diagnosis and localization of parathyroid adenomas using 16-slice SPECT/CT: A clinicopathological correlation.

This study aimed to evaluate a new 16-slice SPECT/CT scanner at Auckland City Hospital for its use in the detection and localization of parathyroid adenomas in patients with primary, secondary and tertiary hyperparathyroidism. The secondary outcome was to compare findings from SPECT/CT with ultrasound and operative findings. One hundred patients who underwent a SPECT/CT scan for primary/secondary/tertiary hyperparathyroidism were included in this study. Of these patients, 45 received surgery. SPECT/CT and ultrasound findings were collated for each patient, and of those who received surgery, operative and pathological findings were compared with those on SPECT/CT. The sensitivity of diagnosis and localization was 86.5% (95% CI: 71.2-95.5%). Specificity was 25.0% (95% CI: 3.2-65.1%). Comparison between SPECT/CT and ultrasound findings demonstrated a kappa coefficient of 0.203 (95% CI: -0.036 to 0.442), correlating with fair agreement. These figures are in line with other published series. The SPECT/CT scanner (and associated reporters) at Auckland City Hospital demonstrates high sensitivity in the detection and localization of parathyroid adenomas and is an effective first-line investigation in patients with primary/secondary/tertiary hyperparathyroidism.

The Detection of Preoperative Parathyroid Lesions: The Success of Ultrasonography, Technetium-99m Methoxyisobutylisonitrile Parathyroid Scintigraphy, and Single-Photon Emission Computed Tomography–Computed Tomography

ObjectiveWe aimed to find and compare the efficacy of ultrasonography (US), technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy (MIBI-S), and single-photon emission computed tomography–computed tomography (SPECT-CT) in detecting the localization of parathyroid adenomas in patients with primary hyperparathyroidism. MethodsIn total, 348 patients were included in this study. Preoperative parathyroid imaging with US, MIBI-S, and SPECT-CT was evaluated and compared with operative findings. The results of the imaging methods were compared with pathology and operation reports. ResultsIn 318 patients (91.3%), one of the imaging methods was able to localize the lesion correctly. US detected the localization of the parathyroid lesions correctly in 268 patients (77%), whereas SPECT-CT and MIBI-S were correct in 254 (73%) and 209 (60%) patients, respectively. There was a statistically significant relationship between the parathyroid hormone (PTH) level and 3 imaging methods’ success rates (P < .05). The PTH cut-off value, which best determined the correct localization, was 152.5 pg/mL for US, 143 pg/mL for MIBI-S, and 143 pg/mL for SPECT-CT. It was observed that the correct localization rate for parathyroid lesions increased with higher PTH levels. ConclusionIn our study population, US was more successful, in most cases, than other imaging methods in localizing parathyroid lesions but SPECT-CT was more accurate in localizing mediastinal lesions. In addition, it was found that preoperative PTH levels affect the accuracy of imaging methods.

Giant versus regular parathyroid adenoma: A retrospective comparative study

BackgroundA fraction of Parathyroid Adenoma (PTA) is considered giant if they weigh more than 3.5 g. There is no clear consensus whether this subgroup has a distinct clinical or biochemical presentation that could have implications on PTA localization and management. In this study, we investigate the difference between regular and giant PTA patients regarding their clinical and laboratory findings as well as their postoperative outcomes. Materials and methodsClinical and PTA-related data were retrospectively retrieved from all patients undergoing parathyroidectomy from 2010 to 2019 at our hospital. ResultsA total number of 84 PTA (Females 76.2%) patients were included, of which 24 (28.6%) qualified as a giant with a mean weight of 7.86 g and the rest were regular adenomas (71.4%) with a mean weight of 1.45 g. Giant adenomas were more likely to present at a younger age compared to regular adenoma patients, (44.4 vs 50.8, P = 0.053, D = 0.470). Preoperative PTH levels were significantly higher in the giant PTA group (650.8 vs 334.2 pg/mL, P = 0.044, r = 0.22). Hospital stay was on average 1.6 days longer in giant PTA patients compared to regular PTA patients. ConclusionGiant PTA compromised a significant percentage of all adenomas, which was higher than what is reported in the literature and might reflect a delay in diagnosis and lack of screening tests. Both giant and regular adenomas seem to run a similar clinical course, yet biochemical abnormalities in PTH levels may have a predictive value for adenoma weight.

Evaluation of diagnostic efficacy for localization of parathyroid adenoma in patients with primary hyperparathyroidism undergoing repeat surgery

PurposeRepeat surgery in patients with primary hyperparathyroidism (pHPT) is associated with an increased risk of complications and failure. This stresses the need for optimized strategies to accurately localize a parathyroid adenoma before repeat surgery is performed. However, evidence on the extent of required diagnostics for a structured approach is sparse.MethodsA retrospective single-center evaluation of 28 patients with an indication for surgery due to pHPT and previous thyroid or parathyroid surgery was performed. Diagnostic workup, surgical approach, and outcome in terms of complications and successful removement of parathyroid adenoma with biochemical cure were evaluated.ResultsNeck ultrasound, sestamibi scintigraphy, C11-methionine PET-CT, and selective parathyroid hormone venous sampling, but not MRI imaging, effectively detected the presence of a parathyroid adenoma with high positive predictive values. Biochemical cure was revealed by normalization of calcium and parathormone levels 24–48h after surgery and was achieved in 26/28 patients (92.9%) with an overall low rate of complications. Concordant localization by at least two diagnostic modalities enabled focused surgery with success rates of 100%, whereas inconclusive localization significantly increased the rate of bilateral explorations and significantly reduced the rate of biochemical cure to 80%.ConclusionThese findings suggest that two concordant diagnostic modalities are sufficient to accurately localize parathyroid adenoma before repeat surgery for pHPT. In cases of poor localization, extended diagnostic procedures are warranted to enhance surgical success rates. We suggest an algorithm for better orientation when repeat surgery is intended in patients with pHPT.

A Case of an Ectopic Parathyroid Adenoma With a Concomitant 99mTc-sestamibi-avid Papillary Thyroid Carcinoma

Background: The evaluation and management of parathyroid adenomas have improved over the years. Localization of parathyroid adenomas in patients with primary hyperparathyroidism was simplified with the use of 99mTc-sestamibi scintigraphy. In the advent of minimally invasive parathyroid surgery, use of radionuclide probes reduced the need for neck exploration and intraoperative frozen section leading to fewer complications, shorter operative time and hospitalization and rapid postoperative recovery. However, limitations of these techniques should be taken into consideration in certain cases. Clinical Case: A 60 year-old female diagnosed with primary hyperparathyroidism presented with recurrent nephrolithiasis and osteoporosis. Initial laboratory evaluation showed elevated serum calcium and intact PTH (1.54 mmol/L and 146 pg/mL, respectively). 99mTc-sestamibi scintigraphy showed a sestamibi-avid focus in the inferior aspect of the right lobe suggestive of a parathyroid adenoma or hyperplasia. Pre-operative neck ultrasound showed non-specific thyroid parenchymal changes and nodules on both lobes with benign sonographic features. She underwent radionuclide-guided focused right parathyroidectomy. The identified enlarged right inferior parathyroid gland registered a highest reading of 70 cps on radionuclide probe. Post-operatively, repeat intact PTH level was still elevated (171.2 pg/mL). There was an interval non-demonstration of the sestamibi-avid focus in the inferior aspect of the right thyroid lobe with an increased sestamibi uptake in the left thyroid lobe compared to the previous parathyroid scan. Histopathologic examination showed a normocellular parathyroid gland and a multifocal papillary thyroid carcinoma. She underwent total thyroidectomy with central neck dissection and 4 parathyroid gland exploration with intraoperative parathyroid hormone assay. However, serial PTH monitoring after left inferior parathyroidectomy and after bilateral partial superior parathyroidectomy still showed elevated levels. Histopathologic examination showed mildly enlarged, normocellular parathyroid gland. The bilateral carotid sheath, retropharyngeal region and superior mediastinum were explored but no ectopic parathyroid tissues were seen. Post-operatively, calcium and PTH were still elevated (1.48 mmol/L and 200.5 pg/mL, respectively). Conclusion: This case highlights the predicaments in the management of parathyroid adenomas, recognizing the possibility of false-positive sestamibi scans due to malignant thyroid nodules and the possibility of the two diseases occurring concurrently, albeit rare.

A retrospective analysis of the diagnostic performance of 11C-choline PET/CT for detection of hyperfunctioning parathyroid glands after prior negative or discordant imaging in primary hyperparathyroidism

BackgroundIdentifying the correct location of a parathyroid adenoma in patients with primary hyperparathyroidism (pHPT) is crucial as it can guide surgical treatment. This study aimed to determine the diagnostic performance of 11C-choline PET/CT in patients with pHPT as a next in-line scan after primary negative or discordant first-line imaging.MethodsThis was a retrospective single-center cohort study. All patients with pHPT that were scanned utilizing 11C-choline PET/CT, after prior negative or discordant imaging, between 2015 and 2019 and who subsequently underwent parathyroid surgery were included. The results of the 11C-choline PET/CT were evaluated lesion-based, with surgical exploration and histopathological examination as the gold standard.ResultsIn total, 36 patients were included of which three patients were known to have Multiple Endocrine Neoplasia (MEN) syndrome. In these 36 patients, 40 lesions were identified on 11C-choline PET/CT and 37 parathyroid lesions were surgically removed. In 34/36 (94%) patients a focused parathyroidectomy was performed, in one patient a cervical exploration due to an ectopically identified adenoma, and in one patient a bilateral exploration was performed because of a double adenoma. Overall, per-lesion sensitivity of 11C-choline PET/CT was 97%, the positive predictive value was 95% and the accuracy was 94% for all parathyroid lesions.ConclusionsIn patients with pHPT and prior negative or discordant first-line imaging results, pathological parathyroid glands can be localized by 11C-choline PET/CT with high sensitivity and accuracy.