123I-MIBG Scintigraphy Research Articles

Laparoscopic resection for retroperitoneum ganglioneuroma with Supine hypotension syndrome

BackgroundSupine hypotension syndrome (SHS) has been reported to occur due to compression by a giant tumor such as ovarian tumor. We herein report a case of retroperitoneal ganglioneuroma with SHS treated with laparoscopic resection.Case presentationThe patient was an 11-year-old male with right-sided abdominal pain. He had a pale complexion and tachycardia while falling asleep. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a giant mass lesion (60 × 35 mm) with compression of the inferior vena cava (IVC) and duodenum ventrally and the right kidney caudally. The IVC was flattened by mass compression. Abdominal ultrasonography (US) revealed narrowing of the IVC due to the mass and accelerated blood flow after IVC stenosis in the supine and left lateral recumbent position. His pale complexion and tachycardia while falling asleep was thought to be due to decreased venous return caused by the tumor compressing the IVC, resulting hypotension. 123I-MIBG scintigraphy revealed no abnormal findings. Tumor markers were normal. He was diagnosed with SHS due to a right adrenal gland tumor. The tumor compressed the IVC from the dorsal side, and hemostasis was expected to be difficult during bleeding. Therefore, a guidewire was inserted from the right femoral vein into the IVC for emergency balloon insertion during bleeding. A laparoscopic tumor resection was performed. A histopathological examination confirmed the diagnosis of primary retroperitoneal ganglioneuroma.ConclusionsThe treatment of symptomatic retroperitoneal tumors requires a multidisciplinary approach.

131I-mIBG Therapy in the Management of High-Risk Neuroblastoma: A Retrospective Study from a Tertiary Level Hospital in South India

Abstract Introduction Neuroblastoma is the most common extracranial solid tumor in childhood. The data on the treatment experience with 131iodine-meta-iodo-benzyl-guanidine (131I-mIBG) and clinical outcome data are meager from India. Objectives This article studies the efficacy and treatment outcomes in patients treated with 131I-mIBG in high-risk neuroblastoma. Materials and Methods The study group consisted of 201 consecutive patients (aged between 1 and 15 years) with biopsy-proven neuroblastoma who underwent 131I-mIBG scans from 2012 to 2022. The majority of these children had a disease that was inoperable or had poor response to chemotherapy. Patients with positive scintigraphy were considered for therapy with 131I-mIBG. The findings were analyzed and correlated with the final diagnosis and outcomes obtained from survival during follow-up and reviewing patient records. Results Thirty-nine children, 22 males and 17 females, with a median age of 4 years had positive 131I-mIBG scintigraphy. Intra-abdominal primary lesions and osseous lesions were the most common sites of uptake on 131I-mIBG scan. Of these, 13 had upfront chemotherapy and 26 had surgery followed by chemotherapy. All the patients underwent therapy with 131I-mIBG. Fourteen patients had multiple therapies while the remaining 25 had only one therapy. Eight patients had no follow-up, and 13 had disease relapse. The remaining 18 had regression of disease which was confirmed by follow-up 131I-mIBG scintigraphy and with bone scintigraphy in patients with osseous metastases. Conclusion 131I-mIBG scintigraphy should be preferred in intermediate and high-risk neuroblastoma to know the extent of the disease and also for patient selection for early therapy with 131I-mIBG. It holds significant utility in the management of metastatic neuroblastoma, facilitating palliative pain relief and tumor size reduction in inoperable or metastatic disease.

Diagnostic Sensitivity and Symptomatic Relevance of Dopamine Transporter Imaging and Myocardial Sympathetic Scintigraphy in Patients with Dementia with Lewy Bodies.

Dementia with Lewy bodies (DLB) presents with various symptoms, posing challenges for early diagnosis challenging. Dopamine transporter (123I-FP-CIT) single-photon emission tomography (SPECT) and 123I-meta-iodobenzylguanidine (123I-MIBG) imaging are crucial diagnostic biomarkers. Hypothesis about body- and brain-first subtypes of DLB indicate that some DLB may show normal 123I-FP-CIT or 123I-MIBG results; but the characteristic expression of these two subtypes remains unclear. This study aimed to evaluate the diagnostic sensitivity of 123I-FP-CIT and 123I-MIBG imaging alone, combined in patients with DLB and explore symptoms associated with the abnormal imaging results. Demographic data, clinical status, and imaging results were retrospectively collected from patients diagnosed with possible DLB. Both images were quantified using semi-automated software, and the sensitivity of each imaging modality and their combination was calculated. Demographic data, cognition, and motor and non-motor symptoms were compared among the subgroups based on the imaging results. Symptoms related to each imaging abnormality were examined using binomial logistic regression analyses. Among 114 patients with DLB, 80 underwent 123I-FP-CIT SPECT (sensitivity: 80.3%), 83 underwent 123I-MIBG imaging (68.2%), and 66 both (sensitivity of either abnormal result: 93.9%). Visual hallucinations differed among the four subgroups based on imaging results. Additionally, nocturia and orthostatic hypotension differed between abnormal and normal 123I-MIBG images. Overall, 123I-FP-CIT SPECT was slightly higher sensitivity than 123I-MIBG imaging, with combined imaging increasing diagnostic sensitivity. Normal results of a single imaging test may not refute DLB. Autonomic symptoms may lead to abnormal 123I-MIBG scintigraphy findings indicating body-first subtype of patients with DLB.

Reduced cardiac 123I-MIBG uptake is a robust biomarker of Lewy body disease in isolated rapid eye movement sleep behaviour disorder

Abstract Cardiac 123I-MIBG scintigraphy is used to assess the function of postganglionic presynaptic cardiac sympathetic nerve endings. 123I-MIBG cardiac uptake is markedly reduced in patients with isolated rapid eye movement sleep behaviour disorder, similar to Parkinson’s disease and dementia with Lewy bodies. As a result, it can be used as an early biomarker of isolated rapid eye movement sleep behaviour disorder. Most patients with isolated rapid eye movement sleep behaviour disorder develop synucleinopathies: Parkinson’s disease, dementia with Lewy bodies or multiple system atrophy. We aimed to investigate whether cardiac postganglionic denervation is present in patients with isolated rapid eye movement sleep behaviour disorder, as well as its possible usefulness as a marker for Lewy body disease status. This retrospective cohort study examined 306 patients (236 men and 70 women; mean age: 68.2 years; age range: 43–87 years) with polysomnography-confirmed isolated rapid eye movement sleep behaviour disorder who were followed for 1–3 months and underwent 123I-MIBG scintigraphy. We retrospectively analysed data from 306 patients with polysomnography-confirmed isolated rapid eye movement sleep behaviour disorder, and their longitudinal outcomes were documented at two centres. Among isolated rapid eye movement sleep behaviour disorder patients, reduced 123I-MIBG uptake was observed in the early and delayed images in 84.4 and 93.4% of patients, respectively, whereas 88.6% of the patients had a high washout rate. This large Japanese two-cohort study (n = 306) found that 91 patients (29.7%) developed an overt synucleinopathy (51 Parkinson’s disease, 35 dementia with Lewy bodies, 4 multiple system atrophy, and 1 cerebellar ataxia) during a mean follow-up duration of 4.72 ± 3.94 years, with a conversion risk of 14.5% at 3 years, 25.4% at 5 years, 41.4% at 8 years and 52.5% at 10 years. On the other hand, among patients with heart-to-mediastinum ratio < 2.2 in the delayed images (n = 286), 85 (29.7%) developed Parkinson’s disease or dementia with Lewy bodies during a mean follow-up duration of 4.71 ± 3.94 years, with a conversion risk of 14.5% at 3 years, 25.6% at 5 years, 42.0% at 8 years and 51.0% at 10 years. Among the 33 patients who underwent repeat 123I-MIBG scintigraphy, there was a progressive decline in uptake over the next 4.2 years, with patients exhibiting reduced uptake progressing to Parkinson’s disease or dementia with Lewy bodies. In contrast, patients without decreased 123I-MIBG uptake progressed to multiple system atrophy. Reduced cardiac 123I-MIBG uptake was detected in over 90% of isolated rapid eye movement sleep behaviour disorder patients, with progression to Parkinson’s disease or dementia with Lewy bodies, rather than multiple system atrophy, over time. Reduced 123I-MIBG uptake is a robust maker for Lewy body disease among isolated rapid eye movement sleep behaviour disorder patients.

Increasing Catecholamine Secretion Through NPY in Pheochromocytomas With False-Negative 123 I-MIBG Scintigraphy.

123 I-MIBG has been well established as a functional imaging tool, and 131 I-MIBG therapy is being considered for catecholamine-secreting tumors. Tumors with the characteristics of a noradrenergic biochemical phenotype, small, malignant, metastatic, extra-adrenal, bilateral, and hereditary, especially SDHx -related tumors, are reported to correlate with reduced MIBG uptake. However, the potential molecular mechanisms influencing MIBG uptake have been poorly studied. To identify critical genes that may enhance MIBG accumulation in pheochromocytomas (PCCs), we performed RNA-seq analyses for 16 operated patients with PCCs (6 MIBG-negative and 10 MIBG-positive) combined with RT-qPCR for 27 PCCs (5 MIBG-negative and 22 MIBG-positive) and examined primary cultures of the surgical tissues. In the present study, 6 adrenal nodules of 66 nodules surgically removed from 63 patients with PCCs (9%) were MIBG negative. MIBG, a guanethidine analog of norepinephrine, can enter chromaffin cells through active uptake via the cellular membrane, be deposited in chromaffin granules, and be released via Ca 2+ -triggered exocytosis from adrenal chromaffin cells. When we compared expression of several catecholamine biosynthesis and secretion-associated genes between MIBG-negative and MIBG-positive tumors using transcriptome analyses, we found that neuropeptide Y, which is contained in chromaffin granules, was significantly increased in MIBG-negative tumors. NPY stimulated norepinephrine secretion dose-dependently in primary cell culture derived from MIBG-positive PCC. In our study, MIBG-negative PCCs were all norepinephrine-hypersecreting tumors. These data indicate that NPY upregulation in PCCs may stimulate chromaffin granule catecholamine secretion, which is associated with false-negative 123 I-MIBG scintigraphy.

Functional and 123I-MIBG scintigraphy assessment of cardiac adrenergic dysfunction in diabetes

ObjectivesTo assess the agreement between clinical cardiovascular adrenergic function and cardiac adrenergic innervation in type 2 diabetes patients (T2D). MethodsThirty-three patients with T2D were investigated bimodally through (1) a standardized clinical cardiovascular adrenergic assessment, evaluating adequacy of blood pressure responses to the Valsalva maneuver and (2) 123I-meta-iodobenzylguanidine (MIBG) scintigraphy assessing myocardial adrenergic innervation measured as early and delayed heart heart/mediastinum (H/M) ratio, and washout rate (WR). ResultsT2D patients had significantly lower early and delayed H/M-ratios, and lower WR, compared to laboratory specific reference values. Thirteen patients had an abnormal adrenergic composite autonomic severity score (CASS > 0). Patients with abnormal CASS scores had significantly higher early H/M ratios (1.76 [1.66–1.88] vs. 1.57 [1.49–1.63], p < 0.001), higher delayed H/M ratios (1.64 [1.51:1.73] vs. 1.51 [1.40:1.61] (p = 0.02)), and lower WR (−0.13(0.10) vs −0.05(0.07), p = 0.01). Lower Total Recovery and shorter Pressure Recovery Time responses from the Valsalva maneuver was significantly correlated to lower H/M early (r = 0.55, p = 0.001 and r = 0.5, p = 0.003, respectively) and lower WR for Total Recovery (r = −0.44, p = 0.01). ConclusionThe present study found impairment of sympathetic innervation in T2D patients based on parameters derived from MIBG cardiac scintigraphy (low early H/M, delayed H/M, and WR). These results confirm prior studies. We found a mechanistically inverted relationship with favourable adrenergic cardiovascular responses being significantly associated unfavourable MIBG indices for H/M early and delayed. This paradoxical relationship needs to be further explored but could indicate adrenergic hypersensitivity in cardiac sympathetic denervated T2D patients.

Cardiac Nuclear Imaging Findings in Atypical Variants of Takotsubo Cardiomyopathy

Background: In addition to the typical form resembling the classical Japanese octopus trap, atypical variants of Takotsubo cardiomyopathy (TTC) sparing the left ventricular apex have emerged over the years. The aim of this systematic review is to provide a comprehensive overview of the cardiac nuclear imaging findings in atypical variants. Methods: This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The literature research was carried out online on the Pubmed, Scopus, Central (Cochrane Library), and Web Of Science databases. Results: A total of 14 articles were ultimately selected. Myocardial perfusion scintigraphy was performed in nine studies, followed by 123I-mIBG scintigraphy, 123I-BMIPP scintigraphy, and 18F-FDG PET. In seven cases, a single cardiac nuclear imaging technique was performed, while in the remaining five and two cases, two and three different imaging modalities were, respectively, used. The most common atypical variant of our selection was the midventricular form, followed by reverse/inverted/basal TTC, with only a single case reported of a focal pattern. Conclusions: As the reason why TTC variants occur is still not clear, a deeper understanding of the current knowledge could be the basis for providing more insights into this fascinating disorder and its uncommon manifestations.

Potential dopaminergic deficit in patients with geriatric psychiatric disorders as revealed by DAT-SPECT: a cross-sectional study

BackgroundIt has been reported that patients with geriatric psychiatric disorders include many cases of the prodromal stages of neurodegenerative diseases. Abnormal 123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane dopamine transporter single-photon emission computed tomography (DAT-SPECT)...

IgG index of cerebrospinal fluid can reflect pathophysiology associated with Lewy bodies in Parkinson's disease

BackgroundNeuroinflammation is one of the pathophysiologies of Parkinson's disease (PD). Lewy bodies, the pathological hallmark of PD, emerge as a consequence of α-synuclein aggregation, and neuroinflammation is induced concurrently with this aggregation. Imaging and cerebrospinal fluid (CSF) biomarkers that reflect PD pathophysiology have been developed or are under investigation. The IgG index of CSF is a marker of inflammation, and may also reflect the pathophysiology of PD. AimWe examined if the IgG index reflects the pathophysiology of PD in drug-naïve PD patients. MethodThe subjects were 20 consecutive PD patients who underwent 123I-MIBG scintigraphy for assessment of the heart to mediastinum (H/M) ratio and wash out rate, 123I-Ioflupane SPECT for examination of the specific binding ratio in the striatum, and lumbar puncture before treatment. The CSF IgG index and levels of pathogenic proteins (total α-synuclein, oligomeric α-synuclein, total tau, phosphorylated tau and amyloid Aβ1–42) were determined. The IgG index was compared with the other parameters using Spearman correlation analysis. ResultsThe IgG index showed a significant correlation with the H/M ratio in early (r = −0.563, p = 0.010) and delayed (r = −0.466, p = 0.038) images in 123I-MIBG scintigraphy and with the CSF total tau level (r = −0.513, p = 0.021). ConclusionNeuroinflammation is involved in PD pathophysiology in some patients, and a higher IgG index indicates the presence of neuroinflammation accompanied by emergence of Lewy bodies.

Sex differences in 123I-mIBG scintigraphy imaging techniques in patients with heart failure

ABSTRACT Background 123I-mIBG-scintigraphy could be a useful stratifying tool for patients with heart failure (HF). The purpose of this retrospective study is to evaluate whether there are differences between men and women with HF in terms of the prediction of cardiac arrhythmic events (AE). Research and methods A total of 306 patients, before implantable-cardioverter-defibrillator (ICD) implantation, were evaluated. They underwent 123I-mIBG-scintigraphy and an evaluation of the results was performed after 85 months of follow-up. Early and late planar and SPECT cardiac images were acquired. Heart-to-mediastinum ratio (HM) for planar images and the sum of the segmental scores (SS) for SPECT were calculated. Results In the general population, age, early SS (ESS), late SS (LSS), and ejection fraction (EF) were statistically significant for the prediction of AE at Cox regression, while early and late HM (eHM,lHM) were not significative for the prediction of AE. Population was divided into females and males and univariate analysis was conducted separately for the two cohorts: no significant variables for prediction of AE were found in females. For males, ESS, LSS, EF, and late HM were statistically significant predictors of AE. The overall survival was similar in males and females, but the risk of AE is lower in males than in females. Conclusions 123I-mIBG represents a more effective tool for the prediction of AE in male patients than in women.

Aberrant positive metaiodobenzylguanidine (MIBG) scan in a patient with gastrointestinal stromal tumor

123I-metaiodobenzylguanidine (MIBG) scintigraphy is an effective means of diagnosing chromaffin-cell tumors such as pheochromocytoma. We report a very rare case of a 45-year-old patient with large intra-abdominal mass and elevated urinary normetanephrines. 123I-MIBG scintigraphy showed mild MIBG uptake. Although initial findings suggested a pheochromocytoma, histologic examination along with immunohistochemical staining revealed features suggestive of gastrointestinal stromal tumor (GIST).

Cardiac sympathetic activity and relationship to cardiac events and left ventricular reverse remodeling in patients with non-ischemic dilated cardiomyopathy.

Delayed heart-to-mediastinum ratio (HMR) has been associated with catecholamine levels and contractile reserve in dilated cardiomyopathy (DCM); however, there is scant evidence regarding the association between cardiac sympathetic activity and left ventricular reverse remodeling (LV-RR). We calculated the 123I-metaiodobenzylguanidine (123I-mIBG) HMR and washout rate (WR) in patients with DCM and investigated their associations with LV-RR. From April 2003 to January 2020, in 120 patients with DCM who underwent 123I-mIBG scintigraphy. 66 patients undergoing follow-up echo and taking a beta-blocker from baseline were examined the relationship between 123I-mIBG and LV-RR. After that, this prognostic value for composite cardiac events was evaluated in the entire 120 patients. In LV-RR analysis, patients were 50.4 ± 12.2years, with a mean left ventricular ejection fraction of 28.6%. Of 66 patients, 28 (42.4%) achieved LV-RR. Multiple logistic regression analysis of LV-RR revealed that not delayed HMR but the WR (cutoff value: 13.5%) was an independent predictor of LV-RR (odds ratio 6.514, p = 0.002). In the analysis for composite cardiac events, even though WR itself does not have the prognostic capacity, Kaplan-Meier survival curves divided by the cutoff value (delayed HMR = 2.0, WR = 13.5) showed that delayed HMR and WR values enabled the stratification of high-risk patients (log-rank p < 0.001). The 123I-mIBG WR was associated with the prevalence of LV-RR in patients taking 100% of beta-blockers and 98.5% of renin-angiotensin system inhibitors. Reflecting the contractile reserve, the combined assessment of the delayed HMR and WR could be used to further precisely stratify the patients with DCM.

The role of MIBG scan in the diagnosis of pheochromocytoma.

e15064 Background: Pheochromocytoma is an uncommon adrenal medulla tumor. Metaiodobenzylguanidine (MIBG) scintigraphy is the current gold standard functional imaging method for evaluating pheochromocytoma, due to its excellent 100% specificity, 80% sensitivity, and general availability. In addition to establishing an extension evaluation and monitoring medication efficacy, MIBG scintigraphy is essential to confirm the diagnosis of suspected pheochromocytoma, especially when there is a tumor-like adrenal mass whose etiology is to be determined and biopsy is contraindicated given the risk of catecholamine discharge with hypertensive flare and the risk of bleeding. Our aims are to determine the efficacy of scintigraphy in the diagnosis of pheochromocytoma by examining the epidemiological characteristic and uptake patterns of the disease. Methods: In a retrospective analysis from January 2010 to December 2020, we examined pheochromocytoma patients medical records who had been referred for MIBG scintigraphy to the regional western Algerian Nuclear Medicine department at the University Hospital Center of Tlemcen. Prior to a progressive intravenous injection of 40–80 MBq of l-MIBG, patients underwent preparation (discontinuation of interfering drugs with I-MIBG especially antihypertensive treatment, thyroid blocking, and hydration). Imaging acquisition was carried out 48 and 72 hours later. Results: Fifty patients with probable pheochromocytoma (sex ratio = 0,78; mean age = 43 [17-74] years) completed I-MIBG scintigraphy prior to adrenalectomy. The MIBG scan has a high specificity and positive predictive value (100%). It confirms the presence of pheochromocytoma in 21 cases (42%), even if the metanephrine is normal in a patient with a non-secreting pheochromocytoma. In 18 cases, the main pattern is a single, homogenous, and intense intra-abdominal uptake. For the three remaining patients, a voluminous and heterogeneous uptake with a photopenic center that was associated to a necrotic adrenal mass larger than 10 cm in size, seen on abdominal Computerized Tomography (CT). In this retrospective analysis, no cases of metastatic or multiple diseases were documented. The sensitivity and negative predictive value are 84% and 86%, respectively. In 29 patients (58%), the scan reveals no abnormalities in uptake. This is attributed, in part, to 30% false positive biology (sampling conditions of urinary and/or plasmatic metanephrines and/or normetanephrines), 20% false positive CT imaging (differential diagnosis of adrenal mass: benign or malignant adrenal nodule), and 8% false negative MIBG scintigraphy (subcentimetric, cystic and necrotic lesion). Conclusions: Due to its exceptional specificity, robust sensitivity, and whole-body staging, MIBG scintigraphy—along with biology and morphology imaging—is a crucial noninvasive diagnostic method for the management of pheochromocytoma prior to adrenalectomy.

High clinical diagnostic accuracy of combined salivary gland and myocardial metaiodobenzylguanidine scintigraphy in the diagnosis of Parkinson's disease.

Decreased myocardial uptake of 131I-metaiodobenzylguanidine (MIBG) is known to be an important feature to diagnose Parkinson's disease (PD). However, the diagnosis accuracy of myocardial MIBG scintigraphy alone is often unsatisfying. Recent studies have found that the MIBG uptake of the major salivary glands was reduced in PD patients as well. To evaluate the diagnostic value of major salivary gland MIBG scintigraphy in PD, and explore the potential role of myocardial MIBG scintigraphy combined with salivary gland MIBG scintigraphy in distinguishing PD from non-PD (NPD). Thirty-seven subjects were performed with 131I-MIBG scintigraphy. They were classified into the PD group (N = 18) and the NPD group (N = 19), based on clinical diagnostic criteria, DAT PET and 18F-FDG PET imaging findings. Images of salivary glands and myocardium were outlined to calculated the MIBG uptake ratios. The combination of left parotid and left submandibular gland early images had a good performance in distinguishing PD from NPD, with sensitivity, specificity, and accuracy of 50.00, 94.74, and 72.37%, respectively. Combining the major salivary gland and myocardial scintigraphy results in the early period showed a good diagnostic value with AUC, sensitivity and specificity of 0.877, 77.78, and 94.74%, respectively. Meanwhile, in the delayed period yield an excellent diagnostic value with AUC, sensitivity and specificity of 0.904, 88.89, and 84.21%, respectively. 131I-MIBG salivary gland scintigraphy assisted in the diagnosis and differential diagnosis of PD. The combination of major salivary gland and myocardial 131I-MIBG scintigraphy further increased the accuracy of PD diagnosis.

Cardiac sympathetic innervation and mortality risk scores in patients with heart failure.

In the risk stratification and selection of patients with Heart Failure (HF) eligible for Implantable Cardioverter Defibrillator (ICD) therapy, 123 I-meta-IodineBenzylGuanidine (123 I-mIBG) scintigraphy has emerged as an effective non-invasive method to assess cardiac adrenergic innervation. Similarly, clinical risk scores have been proposed to identify patients with HF at risk of all-cause mortality, for whom the net clinical benefit of device implantation would presumably be lower. Nevertheless, the association between the two classes of tools, one suggestive of arrhythmic risk, the other of all-causes mortality, needs further investigation. To test the relationship between the risk scores for predicting mortality and cardiac sympathetic innervation, assessed through myocardial 123 I-mIBG imaging, in a population of patients with HF. in HF patients undergoing 123 I-mIBG scintigraphy, eight risk stratification models were assessed: AAACC, FADES, MADIT, MADIT-ICD non-arrhythmic mortality score, PACE, Parkash, SHOCKED and Sjoblom. Cardiac adrenergic impairment was assessed by late Heart to Mediastinum ratio (H/M) <1.6. Among 269 patients suffering from HF, late H/M showed significant negative correlation with all the predicting models, although generally weak, ranging from -0.15 (p=0.013) for PACE to -0.32 (p < 0.001) for FADES. The scores showed poor discrimination for cardiac innervation, with areas under the curve (AUC) ranging from 0.546 for Parkash to 0.621 for FADES. A weak association emerged among mortality risk scores and cardiac innervation, suggesting to integrate in clinical practice tools indicative of both arrhythmic and general mortality risks, when evaluating patients affected by HF eligible for device implantation.

Validation of a Five-Year Prognostic Model Using 123I-metaiodobenzylguanidine Scintigraphy in Patients with Heart Failure.

Background: 123I-metaiodobenzylguanidine (MIBG) scintigraphy evaluates the severity and prognosis of patients with heart failure. A prognostic model has been proposed using a multicenter study data of 123I-MIBG scintigraphy. We evaluated the usefulness of the model using a database. Methods: The study included 208 patients with noncompensated heart failure requiring hospitalization. 123I-MIBG scintigraphy and echocardiography were performed predischarge and 6 months postdischarge. The 5-year mortality rate was calculated by the model and classified into tertiles. Results: In 208 patients, 56 cardiac deaths occurred within the observation period (median, 4.83 years). In the evaluation of predischarge parameters, the predicted 5-year mortality was 15.5% ± 5.0%, 33.5% ± 3.9%, and 51.2% ± 8.2%, and 11 (16.2%), 18 (27.3%), and 27 (36.5%) cardiac deaths occurred in groups 1, 2, and 3, respectively. At the 6-month postdischarge evaluation, the estimated mortality was 8.2% ± 2.2%, 18.5% ± 4.8%, and 43.0% ± 12.1%, and 6 (9.4%), 21 (29.2%), and 29 (40.3%) cardiac deaths occurred, respectively. The predischarge Kaplan-Meier survival analysis showed significant difference between groups 1 and 3 (P value 0.014). Moreover, the 6-month postdischarge evaluation showed significant difference between group 1 and 2, and between groups 1 and 3 (P value 0.016, <0.001, respectively). For groups 1 and 3, the 6-month postdischarge difference was more significant than the predischarge difference (Chi-square 16.7 and 8.1, respectively). Conclusions: The prognostic model using 123I-MIBG scintigraphy was useful in predicting mortality risk in patients with heart failure. The estimated mortality at 6 months postdischarge was more useful than the predischarge estimation for heart failure hospitalization.

Neuroblastoma-related severe hypoperfusion in the cerebellum of an infant: A case of opsoclonus-myoclonus syndrome.

A 2-year-old girl started to wobble without any specific triggers, so the patient was admitted to our hospital's pediatric department. The entire cerebellum showed severe atrophy on MRI and much lower uptake than that in the cerebral cortex on perfusion SPECT. The diagnosis of opsoclonus-myoclonus syndrome (OMS) was suspected. MRI visualized a small mass behind the inferior vena cava. Although its uptake on I-123 MIBG scintigraphy was inconclusive, the mass was surgically removed, and the diagnosis of neuroblastoma was pathologically confirmed. OMS is one of the paraneoplastic neurological syndromes with cerebellar ataxia, myoclonus of the trunk and extremities, and opsoclonus as its main symptoms. Approximately 50% of children cases with OMS are associated with neuroblastoma. The prognosis for neuroblastoma itself with OMS is relatively good, but the neurological prognosis is very poor. If there is decreased blood flow in the cerebellum of an infant, it may be necessary to search for neuroblastoma.

PS-R03-1: A CASE REPORT OF NEUROFIBROMATOSIS TYPE 1 (VON RECKLINGHAUSEN'S DISEASE) WITH HYPERTENSION, ASSOCIATED WITH PHEOCHROMOCYTOMA

The patient is a 75-year-old man, who had multiple neurofibromas on the skin since the age 30 and was clinically diagnosed as neurofibromatosis type 1 (von Recklinghausen's disease) at the age 57, although there was no apparent family history. At the age 70, the patient had excerbated hypertension (home blood pressure 160/90 mmHg) and received amlodipine 5 mg/day. At the age 73, a 35 mm left adrenal tumor was incidentally noted on CT performed with an exacerbation of ulcerative colitis. He was diagnosed with left adrenal pheochromocytoma, due to high levels of urinary metanephrine and normetanephrine shown by urinalysis and an accumulation of 123I on the tumor site shown by 123I-MIBG scintigraphy. After adequate alpha blocking, left adrenal resection was performed. Pathology showed that PASS was 2 points, and MIB1 was 2–3%. Recently, two years after the operation, metanephrine and normetanephrine level has not been increased and keeps in normal range. Hypertension has been improved: Office blood pressure is about 130/70 mm Hg, and home blood pressure 120/70 mmHg, taking doxazosin 2 mg /day only, without amlodipine. Neurofibromatosis type 1 is an autosomal dominant genetic disorder caused by NF1 gene abnormality, characterized by cafe Ole spots and multiple neurofibromas. Pheochromocytomas have been clinically identified in 0.1 to 5.7% of patients with von Recklinghausen's disease (J Urol 1999; 162: 1582). When hypertension is observed in patients with neurofibromatosis type 1 (Recklinghausen's disease), it is important to screen for pheochromocytoma.

PS-BPR01-2: PHEOCHROMOCYTOMA WITH HYPERALDOSTERONISM-LINKED MUTATIONS IN THE POTASSIUM CHANNEL KCNJ5

Context: Recent advances in genetic analysis techniques have led to the genetic analysis of adrenal tumors with hormone excess. In pheochromocytomas, many genetic abnormalities have been identified. Furthermore, several causative genes have been also reported in primary aldosteronism. We performed a comprehensive genetic analysis of functional adrenal tumors using next-generation sequencing. We report here a case of pheochromocytoma with KCNJ5 gene abnormality, which is considered to be specific for primary aldosteronism. Case: A 53-year-old woman with high blood pressure since age 48, excessive sweating and weight loss since age 52, and left ventricular hypertension noted on electrocardiogram during a medical checkup presented to her previous physician. A computed tomography scan of the abdomen showed a right adrenal tumor 30 mm in diameter, and an urinary test showed high levels of urinary metanephrine and normetanephrine (1.42 mg/day) and I-123 MIBG scintigraphy showed an accumulation at the tumor. Plasma renin activity was 0.2 ng/mL/hr, plasma aldosterone concentration was 73.9 pg/mL, and a positive captopril challenge test was performed. Adrenal scintigraphy using 131 I-adosterol showed bilateral adrenal accumulation, suggesting bilateral lesions. Laparoscopic right adrenalectomy was performed for pheochromocytoma. Histology showed focal proliferation of enlarged medullary-like cells and calcification of the adjacent adrenal tissue. The tumor tissue was positive for KCNJ5 gene mutation. A postoperative captopril challenge test was performed again, which was negative. Conclusion: KCNJ5 gene abnormality is considered specific for primary aldosteronism, but was also found in pheochromocytoma. However, the contribution of KCNJ5 gene abnormality to catecholamine production is not yet elucidated. This is a case of pheochromocytoma in which coexistence of primary aldosteronism is also suspected based on the captopril challenge test and imaging findings, and the finding of a gene mutation associated with primary aldosteronism in such a case is very interesting and will warrant further investigation.

PS-BPR01-5: DOPAMINE-SECRETING PHEOCHROMOCYTOMA: AN OVERLOOKED CAUSE OF INCIDENTALLY DISCOVERED ADRENAL TUMOR AND NORMAL BLOOD PRESSURE

A 64-year-old woman with a history of chronic thyroiditis and no family history of endocrine disease was incidentally determined to have a left retroperitoneal mass on abdominal ultrasonography. A subsequent abdominal computed tomography (CT) scan revealed a 5.6 × 5.1 × 10.6 cm left adrenal tumor (10–50 Hounsfield Units of CT attenuation value), which showed marginal irregularity and an internal cystic structure [Figure 1A]. She was admitted to our hospital for further investigation of a suspected adrenocortical carcinoma. On admission, she was normotensive and had no symptoms of catecholamine excess. The 24-hour urine catecholamine level showed normal norepinephrine (122.9 ug/day), epinephrine (24.3 ug/day), whereas markedly elevated dopamine (148,212.4 ug/day). 123I-MIBG scintigraphy revealed tumor uptake. After alpha-blockade as preoperative management, she successfully underwent laparoscopic left adrenalectomy and was finally diagnosed with an exclusively dopamine-secreting pheochromocytoma. The tumor was histologically comprised of small polygonal cells with high cellularity and was immunohistochemically positive for all three catecholamine synthesizing enzymes: tyrosine hydroxylase (very weak), dopamine beta-hydroxylase (heterogeneous), and phenylethanolamine N-methyltransferase (very weak). Electron microscopy revealed very few catecholamine-containing small vesicles with a few organelles, which reflected immature cells. No biochemical or imaging evidence of recurrence or metastasis was evident 1 year after the surgery. To our knowledge, this is the first case of an exclusively dopamine-secreting pheochromocytoma in which immunostaining of catecholamine synthetic enzymes and electron microscopy of tumor tissues were performed together to identify the mechanism underlying a dopamine-secreting PPGL. The purpose of this report was to identify the mechanism underlying a dopamine-secreting pheochromocytoma from the histopathological findings. We also discuss the reasons for the lack of catecholamine excess symptoms, whether preoperative management of alpha-blockade is needed, and the association between the prognosis and genetic mutation with an extensive literature review. JOURNAL/jhype/04.03/00004872-202301001-00862/figure1/v/2023-10-24T163949Z/r/image-jpeg