Incremental Value of Sestamibi SPECT/CT Over Dual-Phase Planar Scintigraphy in Patients With Primary Hyperparathyroidism and Inconclusive Ultrasound

Hyperfunctioning parathyroid gland and skeletal involvement on [18F]fluorocholine PET/CT: one look with two views

Hyperparathyroidism is an endocrine disorder that may be associated with other metabolic diseases. Non-invasive imaging techniques including [^99mTc]Tc-sestamibi single-photon emission computed tomography (SPECT) and [¹⁸F]fluorocholine positron emission tomography (PET)/computed tomography (CT) play a key role on management of patients with hyperparathyroidism. We report for the first time a case of a patient with evidence of both hyperfunctioning parathyroid tissue and multiple lytic bone lesions on [¹⁸F]fluorocholine PET/CT imaging. The present case report highlights the potential role of whole-body [¹⁸F]fluorocholine PET/CT for the identification of both parathyroid adenoma and multiple bone lesions in a single diagnostic setting.

Pituitary metastasis as the first manifestation of lung carcinoma

Pituitary metastases are rare. Clinical presentation could range from asymptomatic to panhypopituitarism or local symptoms. We present a case report of a 43‐year‐old male patient with a new onset headache, visual disturbances, and panhypopituitarism. The investigation led to the diagnosis of pituitary metastasis as the first manifestation of underlying lung cancer.

With rising incidence of breast and lung malignancy, headache/visual field disturbance or signs of pituitary hormone deficiency might be the presenting feature of pituitary metastatic disease. A rapid growth of a sellar lesion and/or the presence of diabetes insipidus along with a sellar mass should raise the suspicion for malignancy.

Comparison of Planar Imaging Using Dual-phase Tc-99m-sestamibi Scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography in Hyperparathyroidism

Objectives:

The aim of this study was to compare Technetium-99m (Tc-99m)-sestamibi dual-phase planar imaging method and delayed phase single photon emission computed tomography/computed tomography (SPECT/CT) imaging in patients with primary hyperparathyroidism and to evaluate the accuracy of scintigraphy with histopathological results.

Methods:

Thirty-six patients with a prediagnosis of hyperparathyroidism, who had not been operated on the neck region before, and were not followed up for any other malignancy, and has confirmed histopathologic and biochemical diagnosis after parathyroidectomy, were retrospectively scanned and included in the study. The images of 36 patients who underwent dual-phase Tc-99m-sestamibi planar scintigraphy at the 20^th and 120^th minutes in the nuclear medicine clinic and delayed phase SPECT/CT imaging immediately after the 120^th minute planar imaging were evaluated visually by two nuclear medicine specialists as positive or negative lesion. Dual-phase planar and SPECT/CT images were statistically compared in terms of sensitivity, specificity, positive predictive value, negative predictive value, and accuracy.

Results:

Thirty-six patients with 41 lesions were evaluated. Comparing dual-phase planar imaging and delayed phase SPECT/CT revealed, sensitivity 84.21%-94.74%, specificity 66.67%-66.67%. Positive predictive value 96.97%-97.30%, negative predictive value 25%-50.0%, accuracy 82.93%-92.68% respectively. There was a statistically significant difference between planar imaging and SPECT/CT; SPECT/CT localized the lesion more accurately (p<0.05).

Conclusion:

SPECT/CT is superior to planar imaging in determining the anatomical details and localization of the lesion, especially in determining the depth of the lesions in the neck and whether it is ectopic. In patients with hyperparathyroidism, SPECT/CT should be used routinely to detect parathyroid pathologies because it has a lower rate of error and higher accuracy rate.

Questionable value of [99mTc]-sestamibi scintigraphy in patients with pHPT and negative ultrasound

PURPOSE

A successful focused surgical approach in primary hyperparathyroidism (pHPT) relies on accurate preoperative localization of the parathyroid adenoma (PA). Most often, ultrasound is followed by [^99mTc]-sestamibi scintigraphy, but the value of this approach is disputed. Here, we evaluated the diagnostic approach in patients with surgically treated pHPT in our center with the aim to further refine preoperative diagnostic procedures.

METHODS

A single-center retrospective analysis of patients with pHPT from 01/2005 to 08/2021 was carried out followed by evaluation of the preoperative imaging modalities to localize PA. The localization of the PA had to be confirmed intraoperatively by the fresh frozen section and significant dropping of the intraoperative parathyroid hormone (PTH) levels.

RESULTS

From 658 patients diagnosed with pHPT, 30 patients were excluded from the analysis because of surgery for recurrent or persistent disease. Median age of patients was 58.0 (13-93) years and 71% were female. Neck ultrasound was carried out in 91.7% and localized a PA in 76.6%. In 23.4% (135/576) of the patients, preoperative neck ultrasound did not detect a PA. In this group, [^99mTc]-sestamibi correctly identified PA in only 25.4% of patients. In contrast, in the same cohort, the use of [¹¹C]-methionine or [¹¹C]-choline PET resulted in the correct identification of PA in 79.4% of patients (OR 13.23; 95% CI 5.24-33.56).

CONCLUSION

[¹¹C]-Methionine or [¹¹C]-choline PET/CT are superior second-line imaging methods to select patients for a focused surgical approach when previous ultrasound failed to identify PA.

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

INTRODUCTION

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Sestamibi Single-Positron Emission Computed Tomography/Diagnostic-quality Computed Tomography for the localization of abnormal parathyroid glands in patients with primary hyperparathyroidism: What clinicopathologic factors affect its accuracy?

PURPOSE

Sestamibi Single-Positron Emission Computed Tomography/Diagnostic-quality Computed Tomography (MIBI-SPECT/CT) is a common technology used for primary hyperparathyroidism (PHPT) localization in clinical practice. However, the clinicopathologic factors affecting the accuracy of MIBI-SPECT/CT and the potential limitations remain unclear.

METHODS

Retrospectively enrolled PHPT patients (n = 280) were analyzed from August 2017 to December 2019.

RESULTS

Of 96 patients with PHPT (mean age, 54 years; 63 females), 17 had discordance between MIBI-SPECT/CT and intraoperative findings. Among the 17 patients with discordance, 58.8% had major discordance, which occurred in most patients with multigland disease (MGD). Compared with concordant patients, discordant patients exhibited increased frequencies of autoimmune thyroid disease (29.4% vs 10.1%, p = 0.035), MDG (41.2% vs 3.8%, p = 0.035), higher PTH (296 pg/mL vs 146 pg/mL; p = 0.012),and lower phosphorus levels (0.77 mmol/L vs 0.90 mmol/L; p = 0.024). MDG (odds ratio [OR], 16.95; 95% CI 2.10-142.86), parathyroid lesion size of 12 mm or less (OR, 6.93; 95% CI 1.41-34.10), and a PTH level higher than 192.5 pg/mL (OR, 12.66; 95% CI 2.17-71.43) were independently associated with discordant MIBI-SPECT/CT results.

CONCLUSION

MGD was most strongly associated with discordance between MIBI-SPECT/CT and intraoperative findings followed by a PTH level higher than 192.5 pg/mL and parathyroid lesion size of 12 mm or less. Surgeons should recognize these potential limitations, which may improve the preoperative procedure by encouraging further localization imaging and promptly facilitate intraoperative troubleshooting.

Personalized nuclear imaging protocol in cases with nodular goiter and parathyroid adenoma

A 62 years old woman was diagnosed with multinodular toxic goiter and primary hyperparathyroidism/left parathyroid adenoma by hormonal assessment, ultrasound and nuclear thyroid/parathyroid scans. Cervical ultrasound illustrated a multinodular aspect of the thyroid with solid nodules and cystic-component nodules; the larger one represented a multinodular complex with necrosis areas in the left thyroid lobe, ACR TI-RADS score 4 (moderately suspicious). Functional nuclear imaging was performed for accurate differential diagnosis between thyroid vs. parathyroid localization, between cold vs. hot nodules, and eventually, for guiding the choice of a subsequent Fine-Needle Aspiration Biopsy (FNAB). Scans described an early intense ^99mTc-sestaMIBI uptake with no ^99mTc-pertechnetate uptake in the left thyroid lobe larger nodule. Due to the suspicion of malignancy for this nodule, we performed an additional scan (1 hour before the classical 2 hours parathyroid delayed scan). The intense uptake persists in both delayed scans suggesting no malignant phenotype and which was confirmed after surgery by benign histology. In conclusion, using a ^99mTc-sestaMIBI personalized protocol, related to the radiotracer cellular uptake mechanisms: 1 hour scan (supplementary image, corresponding to the maximum uptake pattern of ^99mTc-sestaMIBI for cancer cells) and 2 hours scan (for parathyroid washout evaluation) may avoid unnecessary extensive thyroid surgery.

Factors related to a non-localising technetium 99m sestamibi scan result during parathyroid adenoma imaging in primary hyperparathyroidism

OBJECTIVES

The aim of this study is to investigate factors that are associated with having a non-localising ^99m Tc-sestamibi scan.

DESIGN

A retrospective study was performed on patients that underwent parathyroid surgery performed within a single institution between 2001 and 2018.

SETTING

Single tertiary centre for parathyroid surgery.

PARTICIPANTS

230 patients underwent surgery for primary hyperparathyroidism due to a solitary parathyroid adenoma and had preoperative ^99m Tc-sestamibi imaging.

MAIN OUTCOME MEASURES

Variables including age, gender, intra-operative location of parathyroid adenoma, adenoma weight and pre- and postoperative calcium and parathyroid hormone levels were investigated through univariate and multivariate analysis to identify any association with having a non-localising (negative) ^99m Tc-sestamibi scan result.

RESULTS

Multivariate analysis identified that right-sided adenomas (P = .038), superior adenomas (P = .042) and a lower preoperative PTH level (P = .034) were all individual factors associated with having a negative ^99m Tc-sestamibi scan result. Although the weight of the adenoma was significant on univariate analysis (P = .029), this was not demonstrated on multivariate analysis (P = .422).

CONCLUSION

Factors that were associated with having non-localising ^99m Tc-sestamibi scan were right-sided adenomas, superior adenomas and lower preoperative PTH level. Further large prospective multicentre studies are needed to further evaluate these initial findings.

Added value of ultrasonography and Tc-99m MIBI SPECT/CT combined protocol in preoperative evaluation of parathyroid adenoma

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Concomitant use of ultrasonography and MIBI-SPECT/CT is highly recommended for better depiction of parathyroid adenoma.

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It also helps in accurate localization of parathyroid adenoma especially those of ectopic location.

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It will provide better success for parathyroid exploration and minimally invasive surgery.

Purpose

Evaluating the diagnostic performance of combined protocol of ultrasonography and Tc-99 m MIBI SPECT/CT in preoperative depiction and localization of parathyroid adenoma.

Methods and materials

60 patients were enrolled in this retrospective study who had primary hyperparathyroidism and parathyroidectomy for parathyroid adenoma, all of them underwent ultrasonography examination of parathyroid gland and MIBI SPECT/CT for exact pre-operative localization of parathyroid adenoma, surgical and pathological results were used as standard reference then sensitivity, specificity and accuracy for each modalility and for combined protocol of both modalities was calculated.

Results

The sensitivity, specificity and accuracy were highest with combined protocol of ultrasonography and MIBI-SPECT/CT (87 %), (71 %) and (85 %) respectively and lowest sensitivity, specificity and accuracy with ultrasonography alone (76 %), (63 %) and (73 %) respectively while (83 %), (66 %) and (80 %) with MIBI-SPECT/CT alone.

Conclusion

Concomitant use of ultrasonography and MIBI SPECT/CT is highly recommended for better preoperative depiction and localization of parathyroid adenoma.