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Myocardial perfusion imaging (MPI) with single-photon emission computed tomography (SPECT) is a well-established diagnostic approach for patients with suspected or confirmed coronary artery disease (CAD). In the present century, nuclear cardiology has benefited immensely from advances in imaging instrumentation and technology. Dedicated cardiac SPECT cameras incorporating novel, highly efficient cadmium-zinc-telluride (CZT) detectors, collimators, and system designs have evolved as a result of the expansion of nuclear cardiology. A vast amount of evidence is emerging, demonstrating the new technology's advantages over the traditional gamma cameras. Myocardial perfusion imaging (MPI) using gamma-cameras with CZT detectors may be performed with the limited injected activity of radiotracer and recorded times. The use of CZT's dynamic acquisition of myocardial perfusion imaging in clinical practice may help cardiologists in detecting hemodynamically significant CAD. In this article, we present the current state of knowledge on cardiac CZT-SPECT scanners, a summary of the literature published on validation studies, radiation dose reduction, and dynamic acquisition, as well as a comparison of conventional myocardial perfusion imaging with invasive coronary angiography.

Multiple genes and their variants that lend susceptibility to many diseases will play a major role in clinical routine. Genetics-based cost reduction strategies in diagnostic processes are important in the setting of multiple susceptibility genes for a single disease. Head and neck paraganglioma (HNP) is caused by germline mutations of at least three succinate dehydrogenase subunit genes (SDHx). Mutation analysis for all 3 costs ∼US$2,700 per patient. Genetic classification is essential for downstream management of the patient and preemptive management of family members. Utilizing HNP as a model, we wanted to determine predictors to prioritize the most heritable clinical presentations and which gene to begin testing in HNP presentations, to reduce costs of genetic screening. Patients were tested for SDHB, SDHC, and SDHD intragenic mutations and large deletions. Clinical parameters were analyzed as potential predictors for finding germline mutations. Cost reduction was calculated between prioritized gene testing compared with that for all genes. Of 598 patients, 30.6% had SDHx germline mutations: 34.4% in SDHB, 14.2% SDHC, and 51.4% SDHD. Predictors for an SDHx mutation are family history [odds ratio (OR), 37.9], previous pheochromocytoma (OR, 10.9), multiple HNP (OR, 10.6), age ≤40 years (OR, 4.0), and male gender (OR, 3.5). By screening only preselected cases and a stepwise approach, 60% cost reduction can be achieved, with 91.8% sensitivity and 94.5% negative predictive value. Our data give evidence that clinical parameters can predict for mutation and help prioritize gene testing to reduce costs in HNP. Such strategy is cost-saving in the practice of genetics-based personalized health care. [Cancer Res 2009;69(8):3650–6]

Supplementary Table 1 Legends and References from Clinical Predictors for Germline Mutations in Head and Neck Paraganglioma Patients: Cost Reduction Strategy in Genetic Diagnostic Process as Fall-Out

Supplementary Table 1 from Clinical Predictors for Germline Mutations in Head and Neck Paraganglioma Patients: Cost Reduction Strategy in Genetic Diagnostic Process as Fall-Out

Other Supporting Colleagues from Clinical Predictors for Germline Mutations in Head and Neck Paraganglioma Patients: Cost Reduction Strategy in Genetic Diagnostic Process as Fall-Out

Supplementary Table 2 from Clinical Predictors for Germline Mutations in Head and Neck Paraganglioma Patients: Cost Reduction Strategy in Genetic Diagnostic Process as Fall-Out

Pancreatic islet cell tumors (ICTs) occur as sporadic neoplasias or as a manifestation of multiple endocrine neoplasia type 1 (MEN1) and von Hippel–Lindau disease (VHL). Molecular classification of ICTs is mandatory for timely diagnosis and surveillance. Systematic comparison of VHL-ICTs and sporadic ICTs has been lacking. Our registry-based approaches used the German NET-Registry with 259 patients with neuroendocrine tumors (NETs), who were primarily diagnosed with NETs, and the German VHL-Registry with 485 molecular genetically confirmed patients who had undergone magnetic resonance imaging or computed tomography of the abdomen. All patients provided blood DNA for testing of the MEN1 and VHL genes for intragenic mutations and large deletions. In the NET-Registry, 9/101 patients (8.9%) with ICTs had germline mutations, 8 in MEN1 and 1 in VHL. In the VHL-Registry, prevalence of NETs was 52/487 (10.6%), and all were ICTs. Interestingly, of those with VHL p.R167W, 47% developed ICTs, compared to 2% of those with p.Y98H. In total, there were 92 truly sporadic, i.e. mutation-negative ICT patients. Comparing these with the 53 VHL-ICT patients, the statistically significant differences were predominance of female gender (P=0.01), multifocal ICTs (P=0.0029), and lower malignancy rate (PVHL gene, unless they have multifocal ICTs, other VHL-associated tumors, and/or a family history for VHL.

Purpose: Six pheochromocytoma susceptibility genes causing distinct syndromes have been identified; approximately one of three of all pheochromocytoma patients carry a predisposing germline mutation. When four major genes (VHL, RET, SDHB, SDHD) are analyzed in a clinical laboratory, costs are ∼$3,400 per patient. The aim of the study is to systematically obtain a robust algorithm to identify who should be genetically tested, and to determine the order in which genes should be tested. Experimental Design: DNA from 989 apparently nonsyndromic patients were scanned for germline mutations in the genes VHL, RET, SDHB, SDHC, and SDHD. Clinical parameters were analyzed as potential predictors for finding mutations by multiple logistic regression, validated by bootstrapping. Cost reduction was calculated between prioritized gene testing compared with that for all genes. Results: Of 989 apparently nonsyndromic pheochromocytoma cases, 187 (19%) harbored germline mutations. Predictors for presence of mutation are age SDHB>RET>VHL. Using the clinical predictor algorithm to prioritize gene testing and order, a 44.7% cost reduction in diagnostic process can be achieved. Conclusions: Clinical parameters can predict for mutation carriers and help prioritize gene testing to reduce costs in nonsyndromic pheochromocytoma presentations. (Clin Cancer Res 2009;15(20):6378–85)

Glucocorticoid-remediable aldosteronism (GRA), also known as familial hyperaldosteronism type I (FH-I, OMIM 103900), is a monogenic form of inherited hypertension caused by the presence of a chimaeric gene originating from an unequal cross-over between the CYP11B1 (11beta-hydroxylase) and CYP11B2 (aldosterone synthase) genes. The hybrid gene has the CYP11B1 sequence at the 5' end, including the promoter, and the CYP11B2 sequence at the 3' end. The aim of our study was to evaluate the prevalence of GRA in a Polish population of 129 patients with primary hyperaldosteronism (PHA) and 132 patients with essential hypertension (EH), through the use of a PCR-based test revealing the chimaeric gene. None of our PHA or EH patients was positive for the CYP11B1/CYP11B2 chimaeric gene. These data suggest that GRA is unlikely to be a common cause of hypertension in Polish subjects. However, the real prevalence of GRA in Poland, both in the high-risk group of individuals with primary hyperaldosteronism and in the general population, remains to be established.

Primary aldosteronism (PA) is a secondary form of hypertension resulting from the autonomous hypersecretion of aldosterone. The recognition of PA has an important impact on clinical management, since the choice of therapy is different - surgical for adenoma and medical for hyperplasia.To evaluate patients with PA in regard to clinical and biochemical factors differentiating between adenoma of adrenal cortex (APA) and idiopathic adrenal hyperplasia (IHA).We retrospectively analysed 62 patients with PA (33 females, 29 males, mean age 49.3+/-12.5 years, range 26-78) diagnosed in the Department of Hypertension between 1990-2001. In 37 patients (mean age 47.4+/-12.1 years, 22 females, 15 males) APA was diagnosed whereas in the remaining 26 patients (mean age 52.2+/-12.6 years, 14 males, 11 females) IHA was detected. Clinical manifestation, biochemical, serum aldosterone (SA), plasma renin activity (PRA) as well as echocardiographic parameters and blood pressure (BP) levels were evaluated. Diagnostic accuracy of computed tomography (CT) and scintigraphy was also assessed.Mean systolic BP was significantly higher in the patients with APA. Both groups had similar mean diastolic BP. Severe hypertension, resistant to three or more medications, was found in 63.3% of all patients. Muscle weakness was reported by 39.7% of patients, polyuria - by 19%, and polydypsia - by 10.3% of patients. Patients with muscle weakness had higher mean systolic BP level and lower plasma potassium level than patients without this complaint. Symptoms suggesting cardiac arrhythmia were reported by 45% of patients. A normal potassium level was found in 25.8% of all patients. The hypokalemic patients were younger, had shorter known duration of hypertension, higher mean systolic BP level and higher SA concentration than the normokalemic patients. Supine SA levels were significantly higher in the APA group than in the IHA group (50.3+/-29.0 ng% vs 30.5+/-14.7 ng%; p0.001). The SA/PRA ratio higher than 30:1 was found in all patients. Response to postural test with a rise in SA concentration higher than 30% was observed in 40% patients with APA and in 87.5% patients with IHA (p0.0001). There was a strong correlation between supine and upright SA level, and systolic and diastolic BP level as well as plasma potassium level. Left ventricular hypertrophy was present in 60% of patients. The differentiation between APA and IHA was possible using CT, scintigraphy or both methods in 75%, 89.2% and 100% of patients, respectively.One quarter of patients with PA were normokalemic. PA should be suspected especially in patients with severe hypertension, resistant to three or more antihypertensive drugs. Changes in SA concentration during the postural tests such as CT and scintigraphy are useful for differentiation between APA and IHA.