Clinical Use and Utility of Metaiodobenzylguanidine Scintigraphy in Pheochromocytoma Diagnosis

ObjectiveTo examine the indications for metaiodo- benzylguanidine (MIBG) scintigraphy and to assess its performance in localizing pheochromocytoma in the post- computed tomography and magnetic resonance imaging era.MethodsIn this retrospective study, electronic and paper medical records of patients who underwent MIBG scintigraphy at a large academic hospital in Los Angeles, California, between January 1995 and July 2009 were reviewed for indications for MIBG scintigraphy, clinical history, biochemical test results, findings from imaging studies, and pathologic diagnoses. MIBG score was defined as follows: 3 (or intensive uptake) meant MIBG uptake of adrenal gland or other locus was higher than that of the liver; 2 (or moderate uptake) meant uptake was similar to that of the liver; 1 (or borderline uptake) meant uptake was lower than that of liver; and 0 (or negative uptake) meant background signal.ResultsNinety-eight patients underwent MIBG scintigraphy during the study period; the indica- tion was suspected pheochromocytoma in 75 cases. Pheochromocytoma diagnosis was excluded in 48 and con- firmed in 15. The remaining 12 patients had insufficient information in the medical records to render a diagnosis. Among the 63 patients, 47 received ¹³¹I-MIBG and 16 received ¹²³I-MIBG. Sensitivity was 73% and specificity was 69% if any adrenal uptake was considered positive, but increased to 90% if borderline uptake was considered negative. False results were more common in younger patients, but not correlated with biochemical test results. In patients with pheochromocytoma either excluded or con- firmed, the MIBG scintigraphy results were confirmatory in 63%, but misleading in 37%. MIBG scintigraphy results did not provide additional diagnostic value to any case and contributed to pheochromocytoma overdiagnosis and even unnecessary adrenalectomy.ConclusionsMIBG scintigraphy results are either confirmatory or misleading, and this imaging modal- ity is not necessary formost patients in modern practice.(Endocr Pract. 2010;16:398-407)     

On the Utility of MIBG SPECT/CT in Evaluating Cardiac Sympathetic Dysfunction in Lewy Body Diseases

BackgroundAbnormal cardiac uptake of ¹²³I-metaiodobenzylguanidine (¹²³I-MIBG) is a diagnostic marker of Lewy body diseases (LBDs), e.g., Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). Planar imaging is generally used to assess cardiac sympathetic dysfunction in ¹²³I-MIBG scintigraphy; however, its clinical utility requires further improvement. We hypothesized that the co-registration of single-photon emission tomography (SPECT) and computed tomography (CT) images would improve the diagnostic accuracy of ¹²³I-MIBG cardiac scintigraphy for LBDs. This study sought to evaluate the effects of SPECT/CT imaging on ¹²³I-MIBG cardiac scintigraphy for diagnosing LBDs.MethodsWe retrospectively investigated data of 54 patients (consecutive 18 patients in each PD, DLB, and idiopathic normal pressure hydrocephalus [iNPH] groups) who underwent ¹²³I-MIBG cardiac scintigraphy (planar and SPECT/CT) because of suspected LBDs at the Tohoku University hospital from June 2012 to June 2015. We compared the diagnostic accuracies of the conventional planar ¹²³I-MIBG method and SPECT/CT methods (manual and semi-automatic).ResultsIn the conventional planar analysis, ¹²³I-MIBG uptake decreased only in the DLB group compared with the iNPH group. In contrast, the SPECT/CT analysis revealed significantly lower ¹²³I-MIBG uptake in both the PD and DLB groups compared with the iNPH group. Furthermore, a receiver operating characteristic analysis revealed that both the manual and semi-automatic SPECT/CT methods were superior to the conventional planar method in differentiating the 3 disorders.ConclusionsSPECT/CT ¹²³I-MIBG cardiac scintigraphy can detect mild cardiac sympathetic dysfunction in LDBs. Our results suggest that the SPECT/CT technique improves diagnostic accuracy for LBDs.     

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).     

Nonclassic Presentation of Pheochromocytoma: Difficulties in Diagnosis and Management of the Normotensive Patient

ObjectiveTo report an unusual presentation of pheochromocytoma along with challenges in diagnosis and management.MethodsWe report a clinical case history and describe diagnostic methods and pitfalls. The preoperative medical preparation in a normotensive patient is described.ResultsA 33-year-old man fell off a ladder, resulting in C6 paraplegia. After C7-T1 laminectomy, he was transferred to a rehabilitation center where he reported lightheadedness, shortness of breath, and chest pain during therapy sessions. A left adrenal mass was incidentally discovered during the workup to rule out a pulmonary embolism. He reported no history of hypertension, and no elevated blood pressure readings had been documented. Magnetic resonance imaging of the adrenal glands showed a well-defined left adrenal mass measuring 3.9 × 3.2 × 3.3 cm, which was hyperintense on T2-weighted images. Twenty-four hour urinary catecholamine concentrations were unremarkable; urinary metanephrines were markedly elevated. During hospital admission, blood pressure was in the low to normotensive range, requiring a cautious approach to α-adrenergic blockade and surgical preparation. He underwent uneventful laparoscopic left adrenalectomy; surgical pathology was consistent with pheochromocytoma.ConclusionsThis case illustrates a nonclassic presentation of pheochromocytoma and demonstrates that urinary catecholamines alone are not sufficient for a biochemical diagnosis of large pheochromocytomas. Preoperative preparation in normotensive patients can be achieved with α-adrenergic blockade, hydration, and liberal salt intake.     

La scintigraphie myocardique à la 123I-métaiodobenzylguanidine dans les arythmies

Metaiodobenzylguanidine-iode 123 (¹²³I-MIBG) myocardial scintigraphy is one of only the few methods available for the objective evaluation of cardiac sympathetic function at the clinical level. Disorders of cardiac sympathetic function play an important role in a variety of heart diseases and particularly arrhythmic disease. MIBG abnormalities have been described in various arrhythmic diseases. Their signification and their prognostic value are still not clear. This article focuses on reviewing the characteristics of ¹²³I-MIBG myocardial scintigraphy in different arrhythmic diseases.     

Impact diagnostique de l’imagerie hybride TEMP/TDM dans la prise en charge des neuroblastomes. Expérience du service de médecine nucléaire du CHU Mohammed VI de Marrakech

IntroductionThe neuroblastoma is a malignant pediatric tumor of the peripheral sympathetic nervous system. This is the pediatric solid extracranial tumor most common and accounts for approximately 8 to 10% of childhood cancers. The diagnosis is based on imaging showing a tumor developed at the expense of the sympathetic nervous system, increased urinary catecholamines, increased uptake of meta-iodo-benzylguanidine (MIBG) and histology who finds a malignant proliferation of small round cells. An assessment of the tumor mass and its extension are required to assess the prognosis and adapt the treatment. The MIBG scintigraphy is a non-invasive imaging technique that can evaluate with a single review the totality of the tumor extension. The single-photon emission computed tomography/computed tomography (SPECT/CT) improves the sensitivity of the examination, it allows an anatomical and functional study and improves the anatomical localization of scintigraphic uptake observed. The purpose of our work is to illustrate the contribution of the SPECT/CT in addition to the planar MIBG scintigraphy in the diagnosis and staging of neuroblastoma about four cases.Case reportClinical case 1: a 4-year old child, presented for 2 months abdominal pain. In the clinical examination, he presented a hard abdominal mass, painless and right paramedian. Abdominal ultrasound showed a right retroperitoneal mass with lymph nodes. The dosage of urinary catecholamines was increased. The ¹³¹I-MIBG scintigraphy showed an image for a right adrenal neuroblastoma measuring 8.6 × 4.5 cm. Surgical excision of the adrenal mass revealed in the anatomopathologic study a malignant tumoral proliferation with round cells compatible with a neuroblastoma. Clinical case 2: a 10-month old infant, presented since 15 days an exophtalmia with poor general status. The clinical examination showed a right abdominal mass and a bilateral periorbital ecchymosis. The radiography of the thorax showed a widening mediastinal. Abdominal echography showed a tissular mass of the right adrenal gland with retroperitoneal lymph nodes and an ascites. The dosage of urinary catecholamines was increased. The ¹³¹I-MIBG scintigraphy showed a right adrenal neuroblastoma measuring 6.4 × 2.7 cm with orbital bone metastases in favor of a Hutchinson syndrome. Clinical case 3: a 2-month old infant, followed since 1 month for bilateral adrenal neuroblastoma. The clinical examination showed an important abdominal distension with bluish nodules under skin. The abdominal echography and the abdomino-pelvic TDM showed two adrenal masses corresponding to a bilateral neuroblastoma with liver metastases. The ¹³¹I-MIBG scintigraphy showed two adrenal masses measuring respectively 6.5 × 3.4 cm and 8 × 6 cm, with liver and skin metastases in favor of 4S neuroblastoma with bilateral adrenal tumors. Clinical case 4: a 3-year old child, followed for left adrenal neuroblastoma with multiple bone metastases. The clinical examination showed a left abdominal mass with exophtalmia and right palpebral ecchymosis. The radiography of the thorax showed a widening of the mediastin with repression of the paravertebral right line. Abdominal echography showed a left retroperitoneal tissular mass measuring 9.2 × 5.2 cm. The abdomino-pelvic TDM showed a left adrenal tumor with lumbar vertebral bone metastases. A first ¹³¹I-MIBG scan showed a left neuroblastoma with multiple bone metastases in the right orbit, the right humerus, the occipital bone, the right scapula and spine (D10, D11, L1, L3, S1). The child was treated by 5 courses of chemotherapy (protocol HRNLB/10). The ¹³¹I-MIBG scan control showed a regression of neuroblastoma size (1.4 × 1.2 cm) with loss of bone metastases of the occipital bone, the right scapula and spine.DiscussionThe MIBG scintigraphy is a simple, non-invasive examination that has excellent sensitivity and specificity in detection of neuroblastoma and especially in invasion bone marrow and in evaluation of the therapeutic response. The hybrid SPECT/CT imaging improve the performance of the scintigraphy as well in sensibility, toward the deep localization, as in specificity for images poorly defined in planar imaging.     

Performance de la 18FDG-TEP dans le dépistage de paragangliome chez des patients porteurs d’une mutation SDHx

ObjectiveTo evaluate the performance of ¹⁸FDG-PET/CT for detecting infra-clinic paraganglioma (PGL) in SDHx mutation carriers (relatives).Patients and methodsSixty-six patients, from 13 distinct families underwent a genetic testing on the SHD genes between 2003 and 2012. Among the 45 patients with a mutation, 30 with a ¹⁸FDG-PET performed at initial work-up were included in this retrospective study. A gadolinium-enhanced magnetic resonance angiography of the neck (angio-MR) was performed in all cases, a thoracoabdominal-pelvic contrast-enhanced computed tomography (TAP-CT) in 25 cases, a TAP-MR in 20 cases, a ¹²³I-metaiodo-benzylguanidine scintigraphy (¹²³I-MIBG) in 20 cases and a somatostatin receptor scintigraphy (SRS) in 20 cases. Gold standard was histologic or composite (confirmation by another imaging method and follow-up).ResultsA tumor was found in five subjects: 2 abdominal PGL, 1 pheochromocytoma and 2 PGL of the neck. The sensitivity of ¹⁸FDG-PET was 100 %, of SRS was 80 %, of ¹²³I-MIBG was 60 % and of anatomical imaging (association between angio-MR of the neck and TAP-CT and/or TAP-MR) was 100 %. Three false positive lesions were described: 2 with the ¹⁸FDG-PET imaging and 1 with the TAP-MR technique.Conclusion¹⁸FDG-PET/CT is an excellent tool for screening SDHx relatives and should be completed by an angio-MR of the neck if suspicion of abnormality. Association of angio-MR of the neck and TAP-MR has the advantage of being a non-irradiating imaging method but with limited access in some countries.     

Necessity for Long-Term Follow-Up of Patients With Head and Neck Paraganglioma and Mutation in the Succinate Dehydrogenase Genes: An Index Case Report and Literature Review

ObjectiveTo describe a patient with hereditary head and neck paraganglioma (HNPGL) and to review the literature on these rare tumors.MethodsWe review the English-language literature regarding SDH mutations, HNPGL, hereditary paraganglioma-pheochromocytoma syndrome, and the role of functional imaging in the follow-up of these tumors. We also describe the clinical findings, imaging results, and follow-up of a man who initially presented with HNPGL and subsequently developed metastatic pheochromocytoma 20 years later.ResultsA 66-year-old man presented with a history of hypertension, palpitations, sweating, and elevated urinary norepinephrine. Iodine-123-metaiodobenzylguanidine (¹²³I-MIBG) scan demonstrated a left suprarenal mass and multiple avid lesions in the abdomen, chest, and posterior cranial fossa. Histologic examination confirmed aSubmitted for publication February 25, 2012 Accepted for publication May 14, 2012To purchase reprints of this article, please visit: www.aace.com/reprints. Copyright © 2012 AACE.metastatic pheochromocytoma, and molecular genetic testing revealed a mutation in the SDHD gene. The patient had had surgery 20 years earlier for HNPGL. Although most HNPGLs arise sporadically, susceptibility genes have been identified in approximately one-third of cases. Optimal follow-up remains controversial. We reiterate a need for longterm follow-up of patients with a mutation in an SDH gene. ¹²³I-MIBG, highly specific for identifying ectopic neuroendocrine tissue, may have a role in long-term follow-up.ConclusionsAlthough HNPGLs rarely metastasize, their malignant potential is difficult to predict. Routine surveillance for at-risk patients is recommended. Patients with a mutation in an SDH gene should therefore undergo regular surveillance. (Endocr Pract. 2012;18:e130-e134)     

Summary, conclusions, and future directions of [131I]metaiodobenzylguanidine therapy in the treatment of neural crest tumors.

The role of diagnostic [131I/123I]metaiodobenzylguanidine (*I-MIBG) scintigraphy in the management of pheochromocytoma and neuroblastoma is established, but for other neural crest tumors is less defined. Radiopharmaceutical therapy of all these tumors with large activities of suitably radiolabeled MIBG is a compelling concept. In the five years since the first workshop on 131I-MIBG therapy held in Rome, the initial therapeutic promise appears to have been maintained for neuroblastoma and pheochromocytoma. A significant fraction of patients enter partial remission but complete remission is rare and relapse frequent. To date, experience with other neuroendocrine tumors and the use of 125I in place of 131I remains limited. Many promising areas remain incompletely explored. These include development of appropriate in vitro cultures and animal models, basic pharmacological mechanisms, drug interactions, macro- and microdosimetry and human clinical trials. The latter includes determining dose-limiting toxicity of 131I- and 125I-MIBG, treatment of patients at earlier times or stages of disease, optimal integration with other therapy including granulocyte-stimulating factor and marrow transplant rescue from otherwise limiting myelotoxicity. Progress to date has been slow and painstaking, but nevertheless significant, while the future holds both challenges and promise.     

Intravascular Lymphoma: an Unusual Diagnostic Outcome of an Incidentally Detected Adrenal Mass

ObjectiveTo describe a rare diagnosis of intravascular lymphoma in a patient presenting with an incidentally discovered adrenal mass.MethodsWe describe the patient’s clinical history and the findings from biochemical evaluation, radiologic studies, and surgical pathology and review the relevant literature.ResultsA 43-year-old woman developed sudden onset of flank pain associated with a flushing sensation and presented to the emergency department where computed tomography showed a 5-cm left adrenal mass. She had normal electrolytes, and serum and urinary test results were negative for pheochromocytoma. A 24-hour urinary cortisol level was minimally elevated, and the midnight salivary cortisol value was within the reference range. Magnetic resonance imaging revealed a 6.5 × 5.8-cm left adrenal lesion that demonstrated moderate T2-weighted signal and gradual delayed enhancement with no drop in signal on out-of-phase images. Since the lesion lacked high intensity and the biochemical testing results did not suggest a pheochromocytoma, it was deemed likely that the mass was a malignant lesion of the left adrenal gland. A laparoscopic left adrenalectomy was performed. Morphologic and immunohistochemical findings were consistent with a large B-cell lymphoma, which by virtue of its near exclusive distribution in vascular spaces, was consistent with the diagnosis of intravascular large B-cell lymphoma.ConclusionIntravascular large B-cell lymphoma should be included in the differential diagnosis of an incidentally detected adrenal mass even though the diagnosis is rare. (Endocr Pract. 2008;14:884-888)     

No Sex Differences in Use of Dopaminergic Medication in Early Parkinson Disease in the US and Canada - Baseline Findings of a Multicenter Trial

Background

Sex differences in Parkinson disease clinical features have been reported, but few studies have examined sex influences on use of dopaminergic medication in early Parkinson disease. The objective of this study was to test if there are differences in the type of dopaminergic medication used and levodopa equivalent daily dose between men and women with early Parkinson disease enrolled in a large multicenter study of Creatine as a potential disease modifying therapy – the National Institute of Neurological Disorders and Stroke Exploratory Trials in Parkinson Disease Long-Term Study-1.

Methods

Baseline data of 1,741 participants from 45 participating sites were analyzed. Participants from the United States and Canada were enrolled within five years of Parkinson Disease diagnosis. Two outcome variables were studied: type of dopaminergic medication used and levodopa equivalent daily dose at baseline in the Long-Term Study-1. Chi-square statistic and linear regression models were used for statistical analysis.

Results

There were no statistically significant differences in the frequency of use of different types of dopaminergic medications at baseline between men and women with Parkinson Disease. A small but statistically significant difference was observed in the median unadjusted levodopa equivalent daily dose at baseline between women (300 mg) and men (325 mg), but this was not observed after controlling for disease duration (years since Parkinson disease diagnosis), disease severity (Unified Parkinson''s Disease Rating Scale Motor and Activities of Daily Living Scores), and body weight.

Conclusions

In this large multicenter study, we did not observe sex differences in the type and dose of dopaminergic medications used in early Parkinson Disease. Further research is needed to evaluate the influence of male or female sex on use of dopaminergic medication in mid- and late-stage Parkinson Disease.     

Diagnostic Accuracy of 123I-Meta-Iodobenzylguanidine Myocardial Scintigraphy in Dementia with Lewy Bodies: A Multicenter Study

Background and Purpose

Dementia with Lewy bodies (DLB) needs to be distinguished from Alzheimer’s disease (AD) because of important differences in patient management and outcome. Severe cardiac sympathetic degeneration occurs in DLB, but not in AD, offering a potential system for a biological diagnostic marker. The primary aim of this study was to investigate the diagnostic accuracy, in the ante-mortem differentiation of probable DLB from probable AD, of cardiac imaging with the ligand ¹²³I-meta-iodobenzylguanidine (MIBG) which binds to the noradrenaline reuptake site, in the first multicenter study.

Methods

We performed a multicenter study in which we used ¹²³I-MIBG scans to assess 133 patients with clinical diagnoses of probable (n = 61) or possible (n = 26) DLB or probable AD (n = 46) established by a consensus panel. Three readers, unaware of the clinical diagnosis, classified the images as either normal or abnormal by visual inspection. The heart-to-mediastinum ratios of ¹²³I-MIBG uptake were also calculated using an automated region-of-interest based system.

Results

Using the heart-to-mediastinum ratio calculated with the automated system, the sensitivity was 68.9% and the specificity was 89.1% to differentiate probable DLB from probable AD in both early and delayed images. By visual assessment, the sensitivity and specificity were 68.9% and 87.0%, respectively. In a subpopulation of patients with mild dementia (MMSE ≥ 22, n = 47), the sensitivity and specificity were 77.4% and 93.8%, respectively, with the delayed heart-to-mediastinum ratio.

Conclusions

Our first multicenter study confirmed the high correlation between abnormal cardiac sympathetic activity evaluated with ¹²³I-MIBG myocardial scintigraphy and a clinical diagnosis of probable DLB. The diagnostic accuracy is sufficiently high for this technique to be clinically useful in distinguishing DLB from AD, especially in patients with mild dementia.     

Évaluation de l’innervation sympathique cardiaque par la scintigraphie myocardique à la 123I-métaiodobenzylguanidine

Metaiodobenzylguanidine-iode 123 (¹²³I-MIBG) myocardial scintigraphy is one of the few methods available for the objective evaluation of cardiac sympathetic function at the clinical level. Disorders of cardiac sympathetic function play an important role in a variety of heart diseases and particularly in heart failure. MIBG myocardial scintigraphy provides abundance of useful information for evaluation of severity therapeutic effects and prognosis.     

Association of Pheochromocytoma and Ganglioneuroma: Unusual Finding in Neurofibromatosis Type 1

ObjectiveTo report a rare case of association of pheochromocytoma and ganglioneuroma in an asymptomatic patient with neurofibromatosis type 1 (NF1) and to discuss the importance of annual biochemical and imaging studies.MethodsWe present the clinical, laboratory, and pathology findings in a 41-year-old woman with NF1 and review the pertinent literature.ResultsA 41-year-old woman with NF1 presented for a routine gynecologic examination, at which time a right adrenal mass (4 by 3 cm) was discovered by abdominal ultrasonography and confirmed by abdominal computed tomographic scans and magnetic resonance imaging. The patient was normotensive and complained only of discrete essential tremors. Biochemical studies showed a serum epinephrine level of 195 pg/mL (normal,<100) and a 24-hour urine epinephrine excretion of 55 μg (normal,<20), findings consistent with pheochromocytoma. Metaiodobenzylguanidine scintigraphy revealed uptake in the right adrenal gland, with no evidence of metastatic lesions. Before surgical treatment, the patient received an α-adrenergic antagonist for 30 days. Laparoscopic excision of the right adrenal gland yielded excellent postoperative results. Surgical pathology revealed a multinodular mass composed of pheochromocytoma and ganglioneuroma. In patients with NF1 (von Recklinghausen’s disease), a tumor consisting of pheochromocytoma and ganglioneuroma is rare and may be more aggressive than pheochromocytoma alone. An asymptomatic catecholamine-producing tumor may cause substantial morbidity and mortality, especially in patients who are undergoing surgical intervention or are under other stressors.ConclusionThe current guidelines for managing patients with NF1 are an annual history and physical examination. Because of the increased prevalence of pheochromocytoma and ganglioneuroma in patients with NF1, and the potential associated adverse effects, we emphasize the importance of periodic clinical evaluation with biochemical testing and imaging studies. (Endocr Pract. 2007;13:647-651)     

Diagnostic d’une ectopie parathyroïdienne par scintigraphie double traceur

IntroductionA common cause of hyperparathyroidism is the presence of an ectopic parathyroid adenoma. Its diagnostic management remains a challenge and multiple imaging tests exist.Case reportA 39-year-old patient with hyperparathyroidism. At diagnosis, ultrasound and CT were not conclusive. MIBI scintigraphy has objectified a typical parathyroid ectopia in mediastinal position. Surgical resection confirmed parathyroid adenoma allowing standardization of laboratory patient.DiscussionMIBI scintigraphy is the most efficient technique for the diagnosis of hyperparathyroidism, especially in the case of an ectopic parathyroid.     

Acute Myocardial Infarction Attributable to Adrenergic Crises in a Patient with Pheochromocytoma and Neurofibromatosis 1

ObjectiveTo describe a rare case of acute myocardial infarction in a patient with neurofibromatosis 1 and pheochromocytoma and to review the literature on the coexistence of these 2 diseases, the causes of myocardial injury in patients with pheochromocytoma, and the utility of genetic testing and pheochromocytoma screening for those patients and their families.MethodsWe present a case report, including the detailed clinical, laboratory, and radiographic data, results of adrenal mass pathology, and results of coronary angiography. We also survey other relevant reports available in the literature.ResultsA 43-year-old woman with a history of longstanding hypertension, neurofibromatosis 1, headaches, sweating, and palpitations presented to the hospital with chest pain and shortness of breath. She was found to have an acute myocardial infarction and pulmonary edema, as well as a right adrenal mass. A pheochromocytoma was suspected, and phenoxybenzamine was added to her treatment regimen. Cardiac catheterization showed nonobstructive coronary disease. The levels of plasma catecholamine metabolites were extremely high. The patient underwent uncomplicated laparoscopic right adrenalectomy 2 weeks after this admission. Surgical pathology confirmed the diagnosis of pheochromocytoma.ConclusionAdrenergic crisis attributable to pheochromocytoma can result in acute myocardial infarction even in the absence of obstructive coronary disease. Inclusion of pheochromocytoma in the differential diagnosis of hypertension in patients with neurofibromatosis is very important and helps avoid mistakes in the management of such patients. (Endocr Pract. 2007;13:269-273)     

Intérêt de la tomoscintigraphie cardiaque à la 123I-mIBG couplée à la perfusion myocardique dans le diagnostic de l’atrophie multisystématisée

ObjectiveThe aim of this prospective study is to assess the pertinence of using ¹²³I-mIBG myocardial tomoscintigraphy coupled with perfusion scintigraphy as a diagnostic tool, to discriminate between multiple system atrophy (MSA) and idiopathic Parkinson's disease (PD) at first guided by clinical data and L-DOPA tests.Material and methodsForty patients, aged from 43 to 78 years (median 62 years) with Parkinson's syndrome were studied. Nineteen had a diagnosis of PD (criteria of brain bank) and 21 AMS (Gibbs criteria). All were given test to acute L-DOPA. Chest-centered planar imaging (128 × 128 matrix, 5 minutes of duration) is performed at 1 hour and 4 hours after injection of 220 MBq of ¹²³I-mIBG, in addition a non-synchronised tomoscintigraphy (64 × 64 matrix, 32 images of 50 seconds , zoom 1.45) was performed after the 4th hour and 15 minutes after injection of 200 to 400 MBq of ^99mTc-tetrofosmin. Besides neurological data, the parameters retained for comparison purposes with ¹²³I-mIBG cardiac tomoscintigraphy were patients’ age, duration of disease and L-DOPA test results. Two regions of interest (ROI) identical in size and in shape are used for ¹²³I-mIBG uptake quantifications (H/M and washout [Wo]). The first one was placed in projection of mediastinum (M) and the other one in projection of heart (H).ResultsWe found an overall decreased uptake of the myocardial ¹²³I-mIBG without perfusion abnormality in 15 of 19 patients with PD and 11 among them were L-DOPA sensitive (L-DOPA test greater than 30%). Normal tracer uptake with ¹²³I-mIBG associated with an almost quite normal perfusion was seen in 15 of 21 patients with MSA and they were little or not L-DOPA sensitive (L-DOPA test less than 30%). Therefore, 10 discordant cases (25%) between cardiac scintigraphy and clinical evolution of disease with also discordant L-DOPA tests were observed. In the PD group, quantification of data enhanced the diagnostic decision with low heart to mediastinum ratio (H/M) (1.32 ± 0.15 at the early stage and 1.25 ± 0.13 at the later stage). In the MSA group, the uptake of ¹²³I-mIBG (1.66 ± 0.43 at the early stage and 1.72 ± 0.42 at the later stage) was comparable to literature data, however, with significant inter-individual variations. The association of data of scintigraphy with L-DOPA test allows to improve sensitivity in 84% and specificity in 90.5%.ConclusionOur prospective study of 40 cases shows the relevance of cardiac sympathetic postganglionic imaging with ¹²³I-mIBG coupled with myocardial perfusion scintigraphy to discriminate between MSA and PD with a higher sensitivity (71.4%) compared to the test with L-DOPA but a lower specificity (78.9%) than the L-DOPA. The difficulty of diagnosis is firstly linked to damage occurring to both the pre- and postganglionic sympathetic systems in patients with MSA and secondly to the integrity of the sympathetic nerve endings in patients with PD. However, the association of data of scintigraphy with L-DOPA test show a significant improvement of sensibility (84%).     

A Case of Adrenal Cavernous Hemangioma Presenting with Progressive Enlargement and Apparent Hormonal Hypersecretion

ObjectiveTo report the case of a man with an adrenal cavernous hemangioma presenting as a progressively enlarging adrenal mass with apparent hormonal hyper-secretion.MethodsWe report the clinical, laboratory, imaging findings, and clinical course of this patient, and we highlight the important atypical features of this case. The literature is reviewed for the typical presentations of adrenal cavernous hemangiomas.ResultsA 59-year-old man presented with an adrenal incidentaloma that had an imaging phenotype suggestive of a pheochromocytoma or an adrenal carcinoma. The hormonal profile also suggested a state of aldosterone and catecholamine hypersecretion. Surgery, however, proved the diagnosis to be an adrenal cavernous hemangioma.ConclusionAlthough adrenal cavernous hemangioma is a rare entity, it should be considered in the differential diagnosis of an adrenal incidentaloma. Its radiologic features are not specific, and the presence of hormonal hypersecretion does not exclude the diagnosis. (Endocr Pract. 2008;14:104-108)     

Malignant Pheochromocytoma of the Organ of Zuckerkandl Requiring Aortic and Vena Caval Reconstruction

ObjectiveTo describe a case of a malignant pheochromocytoma located in the organ of Zuckerkandl that required aortic and vena caval resection and reconstruction.MethodsWe present a case report that includes clinical, laboratory, and radiographic data as well as photographs, results from pathology, and a brief review of the literature.ResultsA 46-year-old man was referred for evaluation of a 1.4-cm left adrenal mass incidentally discovered on an abdominopelvic computed tomography (CT) scan. Subsequent laboratory evaluation revealed the following values: urine norepinephrine, 252 [μg/24 h; urine normetanephrine, 1122 [μg/24 h; urine metanephrine, 162 μg/24 h; urine epinephrine, 7 [μg/24 h; urine vanillylman-delic acid, 8 mg/24 h; and plasma metanephrine, 98 pg/ mL. Imaging characteristics of the left adrenal mass were consistent with a benign adenoma, but CT also demonstrated a hypervascular paraaortic mass. ¹²³I-metaiodo-benzylguanidine scanning with fusion CT imaging demonstrated increased radiopharmaceutical uptake within the para-aortic mass consistent with a paraganglioma in the organ of Zuckerkandl. Findings from CT angiography of the abdomen and pelvis suggested aortic involvement and vena caval thrombus. The mass was excised en bloc, including portions of the aorta, inferior vena cava, and right ureter. The aorta and vena cava were reconstructed using Dacron grafts. The remaining right ureter and kidney were removed to avoid the possibility of a urine leak from an ureteroureterostomy. Final pathologic and operative findings confirmed a malignant pheochromocytoma of the organ of Zuckerkandl with invasion into the wall of the inferior vena cava and tumor thrombus extending into the lumen.ConclusionMalignant pheochromocytoma of the organ of Zuckerkandl involving the aorta and inferior vena cava is exceedingly rare, and although surgical resection and reconstruction can be radical and aggressive, this treatment offers the only chance for cure. (Endocr Pract. 2007;13:493-497)