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.     

Diagnostic Challenge of Pheochromocytoma in a Patient Receiving Levodopa for Parkinson's Disease

ObjectiveThe diagnosis of pheochromocytoma in patients receiving levodopa is challenging because the standard diagnostic biochemical tests may be confounded by dopaminergic therapy. We aim to showcase our experience with the diagnosis of pheochromocytoma in a patient with a known case of Parkinson’s disease who was receiving levodopa.MethodsWe present the case of an elderly male who was diagnosed as having pheochromocytoma while receiving dopaminergic therapy for Parkinson’s disease.ResultsA 75-year-old man presented with vague abdominal symptoms. Computed tomography revealed a 3.5 × 3.2 cm right adrenal mass with a well-defined margin. As revealed by magnetic resonance imaging, the mass was hypointense on T1-weighted and hyperintense on T2-weighted images. Biochemical tests revealed elevated levels of urinary dopamine, which was considered to be caused by levodopa therapy. However, concurrent elevation in urinary adrenaline and his metanephrine and vanillylmandelic acid levels suggested an underlying case of pheochromocytoma. An ¹²³I-metaiodobenzylguanidine (¹²³I-MIBG) scintigraphy scan performed under levodopa therapy showed positive tracer uptake in the right adrenal gland. Histopathology of the adrenalectomy specimen confirmed the diagnosis of pheochromocytoma.ConclusionOur experience with the present case indicates that although the standard diagnostic biochemical tests for pheochromocytoma may be confounded by dopaminergic therapy, ¹²³I-MIBG scintigraphy has diagnostic value for confirming pheochromocytoma even in patients receiving dopaminergic therapy. (Endocr Pract. 2014;20:e112-e115)     

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.     

Familial Carotid Body Tumors In Patients With Sdhd Mutations: A Case Series

ObjectiveTo describe a family with hereditary paraganglioma due to a disease-causing mutation in the SDHD gene.MethodsWe present the clinical findings, diagnostic test results, treatment, and genetic test results in a family with hereditary paraganglioma.ResultsThree siblings with bilateral carotid body tumors presented at different time points and with varied clinical presentations. While the proband, a 20-year-old man, was not hypertensive and had normal urinary metanephrine and normetanephrine levels, his sister and brother had a more severe clinical picture, with hypertension in both and elevated normetanephrine levels in his brother (his brother had pheochromocytoma and 2 intra-abdominal paragangliomas). Mean age at presentation was 24 years. A 4-base pair frameshift mutation, c.337-340delGACT, was detected in exon 4 of the SDHD gene in all 3 patients.ConclusionThis is the first report of the c.337340delGACT mutation being associated with hereditary paraganglioma; this report emphasizes the need to screen all at-risk first-degree relatives for the disease-causing SDHD mutation once it has been identified in an affected family member. (Endocr Pract. 2012;18:e106-e110)     

High throughput proteomic and metabolic profiling identified target correction of metabolic abnormalities as a novel therapeutic approach in head and neck paraganglioma

Head and neck paragangliomas (HNPGLs) are rare neoplasms that represent difficult treatment paradigms in neurotology. Germline mutations in genes encoding succinate dehydrogenase (SDH) are the cause of nearly all familial HNPGLs. However, the molecular mechanisms underlying tumorigenesis remain unclear. Mutational analysis identified 6 out of 14 HNPGLs harboring clinicopathologic SDH gene mutations. The SDHB gene was most frequently mutated in these patients, and western blot showed loss of SDHB protein in tumors with SDHB mutations. The paraganglioma cell line (PGL-626) was established from a sample that harbored a missense SDHB mutation (c.649C > T). Spectrometric analysis using tandem mass tags identified 151 proteins significantly differentially expressed in HNPGLs compared with normal nerves. Bioinformatics analyses confirmed the high level of enrichment of oxidative phosphorylation and metabolism pathways in HNPGLs. The mitochondrial complex subunits NDUFA2, NDUFA10, and NDUFA4, showed the most significantly increased expression and were localized predominantly in the cytoplasm of PGL-626 cells. The mitochondrial complex I inhibitor metformin exerted dose-dependent inhibitory effects on PGL-626 cells via cooperative down-regulation of NDUFA2, 4, and 10, with a significant decrease in the levels of reactive oxygen species and mitochondrial membrane potential. Further metabolomic analysis of PGL-626 cells showed that metabolites involved in central carbon metabolism in cancer and sphingolipid signaling pathways, pantothenate and CoA biosynthesis, and tryptophan and carbon metabolism were significantly altered after metformin treatment. Thus, this study provides insights into the molecular mechanisms underlying HNPGL tumorigenesis and identifies target correction of metabolic abnormalities as a novel therapeutic approach for this disease.     

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).     

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)     

A Patient with an Apparently Sporadic Pheochromocytoma with a Rearranged During Transfection Codon 635 Variant: A Mild Form of Multiple Endocrine Neoplasia Type 2?

ObjectiveMultiple endocrine neoplasia 2 (MEN2) is an autosomal dominant disorder characterized by medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism, with mutations at codon 634 in exon 11 of the RET (REarranged during Transfection) proto-oncogene identified as the most common genetic defect.MethodsWe present a patient diagnosed with a left adrenal pheochromocytoma at a young age in whom we identified a mutation at codon 635 of the RET gene. No MTC has been clinically detected during a 6-year follow-up.ResultsThe C-to-T point mutation at nucleotide c.1903 results in an additional cysteine in the cysteine-rich domain due to the replacement of arginine with cysteine. One of the patient’s 2 children has the same sequence variant in the RET proto-oncogene and has remained unaffected during follow-up.ConclusionsThe majority of mutations in this disorder affect cysteine residues in the cysteine-rich region of the extracellular domain of the RET protein, disrupting normal cysteine pairing. Consequently, we consider that this variant is likely of pathogenic significance, but this has not been unequivocally confirmed. (Endocr Pract. 2014;20:e65-e68)     

Paraganglioma of the Head and Neck: A Review

ObjectiveTo review the epidemiology, presentation, diagnosis, and management of head and neck paragangliomas.MethodsA literature review of english language papers with focus on most current literature.ResultsParagangliomas (PGLs) are a group of neuroendocrine tumors that arise in the parasympathetic or sympathetic ganglia. Head and neck PGLs (HNPGLs) comprise 65% to 70% of all PGLs and account for 0.6% of all head and neck cancers. The majority of HNPGLs are benign, and 6% to 19% of all HNPGLs develop metastasis outside the tumor site and significantly compromise survival. PGLs can have a familial etiology with germline sequence variations in different susceptibility genes, with the gene encoding succinate dehydrogenase being the most common sequence variation, or they can arise from somatic sequence variations or fusion genes. Workup includes biochemical testing to rule out secretory components, although it is rare in HNPGLs. In addition, imaging modalities, such as computed tomography and magnetic resonance imaging, help in monitoring in surgical planning. Functional imaging with DOTATATE-positron emission tomography, 18F-fluorodeoxyglucose, or 18F-fluorohydroxyphenylalanine may be necessary to rule out sites of metastases. The management of HNPGLs is complex depending on pathology, location, and aggressiveness of the tumor. Treatment ranges from observation to resection to systemic treatment. Similarly, the prognosis ranges from a normal life expectancy to a 5-year survival of 11.8% in patients with distant metastasis.ConclusionOur review is a comprehensive summary of the incidence, mortality, pathogenesis, presentation, workup and management of HNPGLs.     

p.Arg82Leu von Hippel-Lindau (VHL) Gene Mutation among Three Members of a Family with Familial Bilateral Pheochromocytoma in India: Molecular Analysis and In Silico Characterization

Various missense mutations in the VHL gene have been reported among patients with familial bilateral pheochromocytoma. However, the p.Arg82Leu mutation in the VHL gene described here among patients with familial bilateral pheochromocytoma, has never been reported previously in a germline configuration. Interestingly, long-term follow-up of these patients indicated that the mutation might have had little impact on the normal function of the VHL gene, since all of them have remained asymptomatic. We further attempted to correlate this information with the results obtained by in silico analysis of this mutation using SIFT, PhD-SNP SVM profile, MutPred, PolyPhen2, and SNPs&GO prediction tools. To gain, new mechanistic insight into the structural effect, we mapped the mutation on to 3D structure (PDB ID 1LM8). Further, we analyzed the structural level changes in time scale level with respect to native and mutant protein complexes by using 12 ns molecular dynamics simulation method. Though these methods predict the mutation to have a pathogenic potential, it remains to be seen if these patients will eventually develop symptomatic disease.     

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.     

Pheochromocytoma With Histologic Transformation to Composite Type,Complicated By Watery Diarrhea,Hypokalemia, and Achlorhydria Syndrome

ObjectiveTo describe the rare occurrence of histologic transformation of a pheochromocytoma to a composite type of tumor during a long-term follow-up, which was complicated by watery diarrhea, hypokalemia, and achlorhydria syndrome.MethodsWe report the case of a 12-year-old girl who presented with headache, hypertension, and elevated catecholamine levels in the blood and urine. A tumor was found in the right adrenal gland and resected. When she was 15 years of age, multiple metastatic nodules were found in the lung and liver. Intensive chemotherapy was ineffective, and she underwent follow-up with conservative therapy. At 25 years of age, she complained of diarrhea. Laboratory studies revealed hypokalemia and an increase in the level of serum vasoactive intestinal polypeptide (VIP). A year later, she died of extensive metastatic disease. The primary and recurrent tumors at autopsy were histologically examined.ResultsThe primary tumor was pure pheochromocytoma, and the tumors at autopsy were a composite type of pheochromocytoma and ganglioneuroma. Only a few VIP-positive cells were found in the primary tumor, whereas both pheochromocytoma and ganglioneuroma cells of composite tumors were frequently positive for VIP.ConclusionOur case showed histologic transformation from pheochromocytoma to a composite type of tumor during a 14-year clinical course, which was associated with additional hormone production and a change in symptoms. Careful attention should be paid to the alteration of endocrine symptoms and hormone levels during prolonged follow-up of pheochromocytoma in young patients. (Endocr Pract. 2012;18:e91-e96)     

Pheochromocytoma in Neurofibromatosis Type 1: When Should it Be Suspected

ObjectivesNeurofibromatosis type 1 (NF1) carries an increased risk of pheochromocytoma. Most experts recommend that NF1 patients be screened for pheochromocytoma if hypertension develops. We sought to compare NF1 and non-NF1 patients with pheochromocytoma.MethodsRetrospective analysis of a prospectively collected database of all patients undergoing pheochromocytoma resection by a single surgeon from 2003-2012. Statistical significance was evaluated using Fisher’s exact test for categorical variables and the Wilcoxon rank sum test for continuous variables.ResultsOf 56 patients undergoing pheochromocytoma resection, 6 (11%) had NF1. All 6 (100%) NF1 patients had pheochromocytoma diagnosed incidentally during work-up for another condition, whereas 28 of 50 (56%) non-NF1–associated pheochromocytomas were diagnosed incidentally (P = .071). Hypertension was present in 1 (17%) NF1 patient and in 37 (74%) of the non-NF1 patients (P = .011). Tumors were significantly smaller in NF1 patients compared with non-NF1 patients (median tumor dimension, 2.75 cm vs. 5.9 cm, respectively;P = .014).ConclusionAlthough NF1 patients have a well-known increased risk of developing pheochromocytoma, in the current series, all NF1 patients referred to the surgeon for adrenalectomy had pheochromocytoma diagnosed incidentally. Nevertheless, NF1 patients had significantly smaller tumors and less hypertension than other patients treated for pheochromocytoma, perhaps due to a higher frequency of imaging occasioned by their other neoplasms. The common recommendation to screen for pheochromocytoma when hypertension develops would have failed to spur screening in 83% of these NF1 patients. Routine screening for pheochromocytoma in all NF1 patients may be warranted after evaluating whether this is cost-effective in reducing morbidity and mortality. (Endocr Pract. 2014;20:792-796)     

Dietary cholesterol affects sympathetic nerve function in rabbit hearts

In order to assess the effect of hypercholesterolemia on cardiac sympathetic nerve function, New Zealand white rabbits were fed a normal diet (the control group) or one enriched with 0.5% cholesterol [the hypercholesterol (HC) group] for 3 months. Before and after the 3-month diet treatment, we performed serial imaging examinations and analyzed the uptake and washout ratio of¹²³I-meta-iodobenzylguanidine (¹²³I-MIBG) from the myocardium by administration of¹²³I-MIBG through an ear vein. At the end of the experiments, the rabbits were sacrificed, and right ventricular strips were taken from their hearts. The inotropic response of the right ventricular strips to isoproterenol (ISO) and norepinephrine (NE) were evaluated. The cardiac MIBG uptake of the HC group, which was evaluated using the heart to mediastinum ratio, was higher than that of the age-matched control group. However, the washout ratios of¹²³I-MIBG did not differ statistically between the two groups. On pretreatment with cocaine, NE-enhanced contractility was greater in papillary muscles isolated from the HC group. The concentration-response curve to ISO was shifted to the right in the HC group, compared with that in the control group. In conclusion, hypercholesterolemia in rabbits resulted in an increase in sympathetic nerve density in the myocardium, a decrease in the inotropic response to ISO and an increase in the inotropic response to NE in cocaine-treated myocardium. Both the in vivo and in vitro studies demonstrated the functional significance of neural remodeling induced by hypercholesterolemia.     

Évaluation fonctionnelle par TEP 18F-FDopa des paragangliomes et phéochromocytomes non métastatiques : impact de la localisation lésionnelle et du statut génétique

ObjectiveParaganglioma (PGL) and pheochromocytoma (PCC) are neuroendocrine tumors most often benign associated with hereditary syndromes in about 30% of cases. This study aims to define the impact of tumor location and patient genotype on the clinical value of ¹⁸F-FDopa PET by assessing in detail the false negative occurrences.Patients and methodsA retrospective study was conducted on a cohort of 53 cases with non-metastatic sporadic or inherited PGL/PCC (SDHx or VHL related syndromes), investigated with ¹⁸F-FDopa PET.ResultsOverall detection sensitivity of ¹⁸F-FDopa PET was 88%. Seventy-three lesions were found using this technique, including 49 head-and-neck PGL (HNP), two thoracic PGL (1 sympathetic and 1 parasympathetic), eight extra-adrenal retroperitoneal PGL and 15 PCC. The 10 missed lesions were seven extra-adrenal abdominal PGL (2 SDHB, 2 SDHD), two HNP (1 sporadic, 1 SDHD) and one PCC (1 SDHD).Conclusion¹⁸F-FDopa PET is a sensitive technique for the evaluation of non-metastatic head and neck and adrenal PGLs. Exploration of extra-adrenal retroperitoneal PGL associated with SDHB or SDHD syndrome is the main limitation of this technique, encouraging the use of alternative functional imaging modalities like FDG-PET. Negativity of ¹⁸F-FDopa PET in the initial assessment of a PGL should prompt to search for a SDHx mutation.     

Pulsed EPR investigations of the Mo(V) centers of the R55Q and R55M variants of sulfite dehydrogenase from Starkeya novella

Continuous-wave and pulsed electron paramagnetic resonance (EPR) spectroscopy have been used to characterize two variants of bacterial sulfite dehydrogenase (SDH) from Starkeya novella in which the conserved active-site arginine residue (R55) is replaced by a neutral amino acid residue. Substitution by the hydrophobic methionine residue (SDH^R55M) has essentially no effect on the pH dependence of the EPR properties of the Mo(V) center, even though the X-ray structure of this variant shows that the methionine residue is rotated away from the Mo center and a sulfate anion is present in the active-site pocket (Bailey et al. in J Biol Chem 284:2053–2063, 2009). For SDH^R55M only the high-pH form is observed, and samples prepared in H₂ ¹⁷O-enriched buffer show essentially the same ¹⁷O hyperfine interaction and nuclear quadrupole interaction parameters as SDH^WT enzyme. However, the pH dependence of the EPR spectra of SDH^R55Q, in which the positively charged arginine is replaced by the neutral hydrophilic glutamine, differs significantly from that of SDH^WT. For SDH^R55Q the blocked form with bound sulfate is generated at low pH, as verified by ³³S couplings observed upon reduction with ³³S-labeled sulfite. This observation of bound sulfate for SDH^R55Q supports our previous hypothesis that sulfite-oxidizing enzymes can exhibit multiple pathways for electron transfer and product release (Emesh et al. in Biochemistry 48:2156–2163, 2009). At pH ≥ 8 the high-pH form dominates for SDH^R55Q.     

Familial Hyperparathyroidism Due to A Germline Mutation of the Cdc73 Gene: Implications for Management and Age-Appropriate Testing of Relatives At Risk

ObjectiveTo discuss the implications of a young age at diagnosis in a family member with hyperparathyroidismjaw tumor syndrome, the youngest published case to date, due to a mutation of the CDC73 gene (formerly known as HRPT2); to review this family with regard to modifications of guidelines for surveillance of hyperparathyroidism and other associated features in affected and at-risk relatives; and to discuss surgical recommendations in this syndrome.MethodsA review of English-language publications in PubMed and a review of GeneReviews were conducted pertaining to the subject of familial hyperparathyroidism. A case is described, and the family pedigree is discussed.ResultsReview of the literature revealed that CDC73-related disorder has not previously been reported in patients younger than 10 years. This finding has been the basis for the recommendation for initiation of surveillance for disease manifestations at that age. Review of the family history of our current patient revealed a 7-yearold nephew with hypercalcemia attributable to primary hyperparathyroidism.ConclusionSurveillance of hyperparathyroidism in affected persons and genetic testing of relatives at risk are currently recommended to start at 10 years of age. We recommend that these be conducted at a younger age, preferably 5 to 10 years before the earliest diagnosis of hyperparathyroidism within the family, and potentially at birth in families with a known mutation of the CDC73 gene, in light of the malignant potential of the disease. (Endocr Pract. 2011;17:602-609)     

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)     

Cardiac Complications as Initial Manifestation of Pheochromocytoma: Frequency,Outcome, and Predictors

ObjectiveTo examine the frequency, outcome, and clinical predictors of cardiac complications as the initial manifestation of pheochromocytoma.MethodsThe medical records of all 76 patients with pheochromocytoma or functional paraganglioma treated at Cedars-Sinai Medical Center, Los Angeles, California, from 1995 to 2011 were reviewed. The patients initially presenting with cardiac complications were identified, and their clinical, laboratory, and imaging characteristics were compared with those of the patients presenting with other complaints, especially hypertension and adrenal mass.ResultsOf the 76 patients, 9 (12%) presented with the following: 2 with acute heart failure, 1 with left ventricular thrombus, 3 with myocardial infarction, and 3 with severe arrhythmia. Failure to diagnose pheochromocytoma resulted in unnecessary invasive interventions in 2 patients. Recovery of cardiac function was excellent after resection of the tumor in all patients. In comparison with the 67 patients presenting with other complaints, the 9 with cardiac complications had similar demographics and cardiac risk factors but harbored larger tumors (6.7 ± 0.8 cm versus 4.4 ± 0.3 cm; P = .015) and exhibited higher biochemical marker levels (23.9 ± 9.0-fold versus 11.3 ± 2.4fold; P = .082), longer corrected QT interval (473 ± 8 ms versus 443 ± 6 ms; P = .015), and lower ejection fraction (43% ± 8% versus 66% ± 2%; P = .002).ConclusionIn this study, 12% of patients with pheochromocytoma initially presented with cardiac complications. Patients with large tumors and high levels of biochemical markers were more likely to develop cardiac injury. Our results confirm that the presence of pheochromocytoma should be ruled out in patients with cardiac diseases and features suggesting pheochromocytoma so that unnecessary interventions can be avoided and cardiac recovery can be achieved. (Endocr Pract. 2012;18:483-492)