Preoperative Adenoma Localization Research Articles

11C-methionine PET/CT and conventional imaging techniques in the diagnosis of primary hyperparathyroidism.

It is well known that primary hyperparathyroidism (PHPT) is one of the most common endocrine disorders. Precise preoperative adenoma localization is essential for increasing PHPT cure rate. Conventional localization techniques include neck ultrasound, 99m-Tc-sestamibi scintigraphy, and computed tomography (CT). However, all of these methods have limitations. 11C-methionine positron emission tomography/computed tomography (PET/CT) combines both anatomical and functional modalities; it may be useful in terms of lowering the imaging procedures number and improving accuracy. A retrospective diagnostic accuracy study with sensitivity and specificity evaluation was conducted. We studied the data of 91 patients with PHPT, who were hospitalized at Almazov National Medical Research Centre. Medical records, lab results, and CT imaging of all patients were analyzed. All of them underwent ultrasound. 99m-Tc-sestamibi/99m-Tc-pertechnetate subtraction scintigraphy and CT were performed on 56 and 86 patients, respectively. Since 2020 11C-methionine PET/CT has been performed on 45 patients. Then, minimally invasive parathyroidectomy (PTX) was carried out in all patients. Histological results were used as a benchmark in order to evaluate diagnostic accuracy of studied methods. Parathyroid adenoma or hyperplasia was confirmed in all patients. Multiple lesions were found in 5 patients. Nineteen lesions were ectopic. All patients with multiple lesions required at least 3 localization techniques, and 2 of them required 4. The sensitivity of 11C-methionine PET/CT was 98%, CT, 99m-Tc-sestamibi scintigraphy, and ultrasound showed sensitivity at 75%, 79%, and 67%, respectively. The estimated specificities of 11C-methionine PET/CT, CT, 99m-Tc-sestamibi scintigraphy and ultrasound were 93%, 73%, 75%, and 70%, respectively. Our study showed that 11C-methionine PET/CT has higher sensitivity and specificity than conventional techniques in a group of 19 patients. 11C-methionine PET/CT may take a place in the imaging of parathyroid adenomas, it may replace CT and 99m-Tc-sestamibi scintigraphy while simultaneously providing information about lesion topography and function.

Perioperative Clinical Features of Mediastinal Parathyroid Adenoma: A Case Series

Rare ectopic mediastinal parathyroid adenoma can result in persistent or recurrent hyperparathyroidism. In this article, we summarized the perioperative outcomes of six patients with mediastinal parathyroid adenoma. All patients underwent minimally invasive surgery (MIS). Abnormal accumulation of sestamibi was observed in four of five patients for preoperative localization of adenoma. Postoperatively, the blood calcium dropped quickly. In addition, we found adenoma function was negatively related to adenoma volume in these patients. In conclusion, although MIS is feasible for parathyroid adenoma, blood calcium should be monitored in a timely manner to avoid hypocalcemia postoperatively. In addition, sestamibi might be a potential pitfall when locating parathyroid adenoma.

How to do depends on where it settles: Mediastinal parathyroid adenomas.

In this study, we aimed to evaluate demographic characteristics, preoperative adenoma localization, surgical techniques selected according to the size and localization of adenoma, and clinical results of patients undergoing mediastinal parathyroid adenoma excision. Medical records of a total of 11 patients (4 males, 7 females; mean age 52.6 years; range, 25 to 65 years) who underwent excision of mediastinal parathyroid adenoma in our clinic between January 2011 and June 2019 were retrospectively reviewed. Data including demographic characteristics, complaints, preoperative serum calcium, phosphorus, and parathyroid hormone levels, preoperative imaging methods, surgical method, localization and size of adenoma, length of hospital stay, and duration and amount of drainage were recorded. Adenoma was localized in anterior mediastinum in seven patients and in the middle mediastinum in four patients. The mean diameter calculated by taking into account the longest diameter of parathyroid adenoma was 21.1 mm. The mean drainage duration was 3.5 days in two patients undergoing median sternotomy, five days in one patient undergoing thoracotomy, 1.2 days in three patients undergoing video-assisted thoracoscopic surgery, and 0.6 days in five patients undergoing robotic surgery. Minimally invasive approaches such as videoassisted thoracoscopic surgery and robotic-assisted surgery are safe and effective approaches for excision of mediastinal parathyroid adenoma.

Value of [11C]-methionine PET/CT in preoperative localization of adenomas in primary hyperparathyroidism

Value of [11C]-methionine PET/CT in preoperative localization of adenomas in primary hyperparathyroidism

Preoperative Localization of Adenomas in Primary Hyperparathyroidism: The Value of 11C-Choline PET/CT in Patients with Negative or Discordant Findings on Ultrasonography and 99mTc-Sestamibi SPECT/CT.

We aimed to assess the value of 11C-choline PET in patients with primary hyperparathyroidism and negative or discordant results on 99mTc-sestamibi imaging and neck ultrasound. Methods: Eighty-seven such patients were assessed and subsequently underwent parathyroidectomy. PET/CT image data were analyzed semiquantitatively using SUVmax and SUV ratios (target to contralateral thyroid gland and carotid artery). A positive PET/CT result was defined as focal uptake significantly higher than regular thyroid tissue. Ectopic foci were also considered positive. Inconclusive PET/CT cases were defined as a lesion with uptake equal to normal thyroid tissue. If no prominent or ectopic uptake was detectable, the PET/CT result was considered negative. Results: When dichotomizing the 11C-choline PET/CT imaging results by defining lesions with both positive and inconclusive uptake as positive, we found 84 of 92 lesions (91.3%) to have true-positive uptake whereas 8 lesions (8.7%) had false-positive uptake. One lesion showed false-negative uptake; the sensitivity was 98.8%. The corresponding positive predictive value for lesions was 91.3%. The mean SUVmax was 6.15 ± 4.92 in 72 lesions with positive uptake (70 patients) and 2.96 ± 2.32 in 20 lesions with inconclusive uptake (18 patients). Conclusion: These results in a large group of patients indicate that 11C-choline PET/CT is a promising tool for parathyroid adenoma localization when ultrasound and 99mTc-sestamibi imaging yield negative or discordant results.

Unilateral Exploration for Parathyroid Adenoma.

Between January 2012 to 2016, 20 patients with primary hyperparathyroidism underwent surgical exploration for presumed diagnosis of parathyroid adenoma. Nineteen patients underwent ultrasonography of neck and USG was found to be accurate in localizing the adenoma in 84.2%. Seventeen patients underwent sestamibi isotope scanning and imaging correlated with operative findings in 94.1%. Combined accuracy of ulrasound and sestamibi scan which was done in 17 patients was 95%. Seventeen patients underwent unilateral exploration and there was resolution of disease in 94.1%. Three patients underwent bilateral exploration and had a success rate of 100% in the removal of offending adenoma. Fifteen minutes post excision, rapid intraoperative intact parathormone assay was sent in 14 out of 17 unilateral explorations and was found to have true positive rate of 93% and false positive rate of 7%. There was a significant difference in the operating time between unilateral (17 patients, mean operating time 1h) and bilateral (3 patients, mean operating time 1¾hrs) explorations. It is clear from this study; the preoperative localization of adenoma with plan for unilateral exploration with a combination of ultrasonography and sestamibi scan is extremely useful if unilateral exploration is planned for excision of parathyroid adenoma. However, the number of patients who underwent 15min post excision intact parathormone assay, is a small number to comment on its usefulness in predicting the success of unilateral exploration.

Successful minimally invasive surgery for primary hyperparathyroidism: influence of preoperative imaging and intraoperative parathyroid hormone levels.

Adenoma is the main parathyroid disorder leading to primary hyperparathyroidism (PHP). Minimally invasive parathyroidectomy (MIP) is recognized as a valid procedure for adenoma-related PHP. It requires precise preoperative localization combining Tc-99m-MIBI (methoxy-isobutyl-isonitrile) scintigraphy and single-photon emission computed tomography (SPECT) with x-ray computed tomography (CT) and intraoperative confirmation of successful excision by change in intact parathormone (iPTH) levels. The study aim was to assess the surgery success in relation to these two parameters. All patients operated on for PHP from 2005 to mid-2014 at our institution were retrospectively reviewed. MIP was performed in case of precise preoperative adenoma localization on scintigraphy, absence of past cervical surgery, and absence of concomitant thyroid resection necessity. In these patients, iPTH levels were monitored intraoperatively. Confirmation criteria for iPTH values were a return to normal level or a decrease >50 % of basal iPTH level. There were 197 PHP operations during the study period: 118 MIP and 79 bilateral neck explorations (BNEs). The MIP success rate was 95 % (112/118) with a preoperative MIBI scan ± CT accurate in 94 % (111/118) of the patients and with correct iPTH in 90 % (106/118) of the cases. Among the 12 iPTH levels that did not meet the confirmation criteria, 10 returned to normal range by postoperative day 2. Treatment failure appeared in three patients (one BNE, two MIPs). Tc-99m-MIBI dual-phase scintigraphy with SPECT/CT is the key examination for functional and morphological parathyroid adenoma localization. If preoperative scintigraphy is obvious and intraoperative assessment is clear, one could possibly safely omit iPTH, as it may lead to unnecessary BNE in primary PHP.

Determination of the Localization by Intra-arterial Calcium Stimulation in Insulinoma: A Case Report

Aims: Insulinoma, though a very rare disease, is the most common endocrine tumors of the pancreas. High serum insulin levels during hypoglycemic episodes are specific for the diagnosis. Where ultrasonography, tomography and other imaging modalities are not adequate for determination of the adenoma and its localization, hepatic venous sampling method with selective intra-arterial calcium stimulation becomes important in terms of determination of preoperative localization of adenoma and shortening surgery time. Presentation of Case: A 38-year-old female patient investigated for weakness and low blood glucose was examined with a prediagnosis of insulinoma. Although clinical and laboratory results suggested insulinoma, no focus could be found by routine imaging methods. Hepatic venous sampling with selective intra-arterial calcium stimulation of the patient, who had pancreatic angiography, was performed. As a result of calcium stimulation performed from proximal splenic, mid splenic and gastroduodenal arteries, insulin and C-peptide levels in blood samples collected from hepatic vein were found to be high. The patient underwent an operation with intraoperative Case Study Evran et al.; BJMMR, 9(12): 1-5, 2015; Article no.BJMMR.19978 2 ultrasonography in which mass excision of the pancreas tail was performed. Pathologic examination revealed a neuroendocrine tumor showing synaptophysin, chromogranin and NSE (+) staining. Discussion and Conclusion: Hepatic venous sampling with selective intra-arterial calcium stimulation in insulinomas is an extremely accurate and reliable method for the preoperative

4D‐CT for Localization of Nonlocalizing Parathyroid Adenomas in Primary Hyperparathyroidism

Objectives: (1) Present the application of 4-dimensional (4D) computed tomography (CT) in preoperative localization of parathyroid adenomas that do not localize with technetium-99 (Tc-99) single-photon emission computed tomography (SPECT)/CT or ultrasound. (2) Present indications for 4D-CT use. (3) Understand radiologic dosimetry issues of 4D-CT. Methods: A retrospective review of over 15 consecutive patients at an academic medical center with primary hyperparathyroidism who underwent preoperative 4D-CT after nonlocalizing preoperative ultrasound and Tc-99 SPECT-CT scans between November 2013 and June 2014. This was a mixture of patients presenting for their first operations and others requiring revision surgery. Intraoperative radioguided parathyroidectomy results, excised gland weight, patient demographics, and parathyroid hormone levels were recorded. Sensitivity, specificity, and positive and negative predictive values of 4D-CT for preoperative adenoma localization were calculated. Results: 4D-CT resulted in successful localization and biochemical cure in all primary or revision cases in which it was utilized. Radiation doses from 4D-CT will be presented and compared to radiologic dosimetry from SPECT-CT. Conclusions: 4D-CT offers a sensitive and specific modality for preoperative parathyroid adenoma localization which is useful in cases where ultrasound and SPECT-CT sestamibi are nonlocalizing.

Predictors of accuracy in preoperative parathyroid adenoma localization using ultrasound and Tc-99 m-Sestamibi: A 4-quadrant analysis

PurposeTo compare the accuracy of preoperative parathyroid adenoma localization in patients with primary hyperparathyroidism (pHPT) due to a single adenoma using a detailed 4-quadrant analysis and to identify patient and tumor characteristics associated with accurate preoperative localization. Materials and MethodsRetrospective review of 203 patients who underwent parathyroidectomy for pHPT due to a single adenoma between 2008 and 2011. Results from preoperative ultrasound and Tc-99m-sestamibi were compared to operative findings to determine accuracy of localization studies. Associations between clinicopathologic features and accurate preoperative adenoma localization were evaluated. ResultsUltrasound was performed on 198 patients, sestamibi on 177 patients, and both on 172 patients. Accurate localization occurred significantly more often for ultrasound than sestamibi (63% vs. 41%, P<0.001). For ultrasound, accurate localization was found in patients with larger or heavier adenomas, those with adenomas located inferiorly, patients not having a reoperative procedure, and patients with higher post-operative serum calcium levels. For sestamibi, greater adenoma size or weight, adenomas located inferiorly, and patients with associated thyroid cancer on pathology were most predictive of accurate preoperative localization. ConclusionsOur results provide evidence that ultrasound is more accurate in localizing parathyroid adenomas in patients with pHPT due to a single adenoma when compared to sestamibi scan using 4-quadrant location analysis and may be the preferred preoperative imaging modality in these patients. No significant preoperative patient factors were associated with accurate localization by ultrasound or sestamibi, but adenoma size, weight, and location in an inferior position were predictive of accurate preoperative localization.

Fusion imaging for parathyroid localization in primary hyperparathyroidism

Primary hyperparathyroidism, most commonly due to a solitary parathyroid adenoma, has become an increasingly diagnosed condition and is one with great potential for cure following appropriate surgical intervention. Functional imaging with Tc-99m-based radiopharmaceuticals has contributed significantly to increased success in preoperative adenoma localization but the advent of fusion of this functional information with anatomical details obtained with computed tomographic imaging has yielded a potentially more powerful clinical tool and one that is particularly well suited to ectopic adenomas and cases of prior failed surgery. Aspects of this modality are discussed with reference to software- and hardware-based fusion techniques and evidence for efficacy. The allied technique of PET/computed tomography is also discussed.

First experience with minimally invasive video-assisted parathyroidectomy

Background: Rapid development of endoscopic procedures has brought about innovation in the field of minimally invasive operative techniques. In consequence of improvement of preoperative localization diagnostics and intraoperative control measures, minimally invasive videoassisted parathyroidectomy (MIVAP) has been expanded to the field of parathyroid surgery. Methods: Patients with preoperative localization of adenoma in primary hyperparathyroidism were selected in case of primary surgical intervention of the neck in a video-endoscopically assisted technique. Preoperative localization was performed by ultrasonography and sestamibi scintigraphy. Intraoperatively, quick-PTH-levels were assessed for control of successful adenoma-exstirpation. Results: Of 62 patients with the diagnosis of PHPT, 16 patients could be selected for MIVAP. 13 out of 16 patients could be successfully completed applying the MIVAP-procedure. In 3 cases conversion to conventional parathyroidectomy became necessary. Morbidity was 6 % with 1 unilateral transient recurrent nervepalsy. There was no unsuccessful intervention in regard to the underlying disease, there was no recurrence of PHPT so far. In 2 cases additional resection of a thyroid nodule was performed videoassistedly. There was no case of postoperative hypoparathyroidism. Conclusions: The preliminary experiences and results of MIVAP encourage further clinical experience in favour of it’s good results cosmetics results and advantages of shortened hospital stay and no postoperative hypoparathyroidism.

The use of preoperative localization of adenomas of the parathyroid glands by thallium technetium subtraction scintigraphy, high-resolution ultrasonography, and computed tomography : Roses DF, Sudarsky LA, Sanger J, et al. (New York University Medical Center, 530 First Avenue, New York, NY 10016, U.S.A.) Surg Gynecol Obstet 1989;168:99–106

Thirty-six patients with primary hyperparathyroidism were studied preoperatively by thallium-201 and technetium-99m pertechnetate subtraction (Tl-201/Tc-99m) scintigraphy, high-resolution real time ultrasonography and computed tomographic (CT) scanning. None of the patients had had previous surgical treatment of the parathyroid or thyroid glands. All of the patients underwent systematic bilateral exploration of the neck. All of the patients were successfully explored and 41 abnormal parathyroid glands were identified. Five patients had two adenomas. In six instances, adenomas were identified in ectopic anatomic sites. The sensitivity of correctly localizing the abnormal glands with these techniques was 49 per cent for the Tl-201/Tc-99m scintigraphy, 34 per cent for ultrasonography and 41 per cent for CT scanning. The Tl-201/Tc-99m scintigrams detected two of the six ectopically located adenomas, CT detected one, while ultrasound detected none. The five patients with multiple adenomas were not accurately identified as having multiple gland enlargement by any of these studies. Therefore, preoperative localization studies with these three techniques did not provide reliable information for initial bilateral exploration of the neck.

Computed tomography in the localization of aldosterone-secreting adrenal adenomas.

Computed tomography (CT) has been shown to detect both adrenal glands in 88.5% of upper abdominal examinations and can visualize at least one gland in 96.5% of patients. However, in examinations carried out specifically to visualize the adrenals, the glands were located in 98% of cases. This technique was used in 18 patients with primary aldosteronism to localize aldosterone-secreting adrenal tumours and to distinguish these from non-adenomas (bilateral adrenal hyperplasia). The results were compared with quadric analysis, a statistical technique used to predict the likely surgical outcome. In seven patients the CT results were verified by operation (six adenomas, one adrenal hypertrophy). However, in one further patient a large adenoma (20 mm in diameter) which had not been predicted by CT scanning was found at operation. In the remaining ten patients who have been medically treated, results concordant with quadric analysis were obtained in eight cases. We would suggest that CT scanning should be the initial investigation for the pre-operative localization of adenomas but further comparative studies are required.

Echographische Lokalisationsdiagnostik von Adenomen und Hyperplasien der Nebenschilddrüse beim primären Hyperparathyreoidismus

The results of echographic localization of adenomas and hyperplasia of the parathyroid glands in seven patients with primary hyperparathyroidism are reported. In four patients there was complete, and in three patients partial, agreement between the echographic diagnosis and the findings at surgery and histology. On the basis of this experience and the findings of other authors, echography must be regarded at present as the best method for pre-operative localization of adenomas and hyperplasia of the parathyroid gland.

Nephrology: An Annotated Bibliography of Recent Literature

Nephrology: An Annotated Bibliography of Recent Literature