Diagnosis and Management of Hereditary Phaeochromocytoma and Paraganglioma

Clinical Syndromes and Genetic Screening Strategies of Pheochromocytoma and Paraganglioma

Pheochromocytomas (PCCs) are rare neuroendocrine tumors that originate from chromaffin cells of the adrenal medulla, and paragangliomas (PGLs) are extra-adrenal pheochromocytomas. These can be mainly found in clinical syndromes including multiple endocrine neoplasia (MEN), von Hippel–Lindau (VHL) syndrome, neurofibromatosis-1 (NF-1) and familial paraganglioma (FPGL). PCCs and PGLs are thought to have the highest degree of heritability among human tumors, and it has been estimated that 60% of the patients have genetic abnormalities. This review provides an overview of the clinical syndrome and the genetic screening strategies of PCCs and PGLs. Comprehensive screening principles and strategies, along with specific screening based on clinical symptoms, biochemical tests and immunohistochemistry, are discussed.

A Next-Generation Sequencing Primer-How Does It Work and What Can It Do?

Next-generation sequencing refers to a high-throughput technology that determines the nucleic acid sequences and identifies variants in a sample. The technology has been introduced into clinical laboratory testing and produces test results for precision medicine. Since next-generation sequencing is relatively new, graduate students, medical students, pathology residents, and other physicians may benefit from a primer to provide a foundation about basic next-generation sequencing methods and applications, as well as specific examples where it has had diagnostic and prognostic utility. Next-generation sequencing technology grew out of advances in multiple fields to produce a sophisticated laboratory test with tremendous potential. Next-generation sequencing may be used in the clinical setting to look for specific genetic alterations in patients with cancer, diagnose inherited conditions such as cystic fibrosis, and detect and profile microbial organisms. This primer will review DNA sequencing technology, the commercialization of next-generation sequencing, and clinical uses of next-generation sequencing. Specific applications where next-generation sequencing has demonstrated utility in oncology are provided.

Prediction of inherited genomic susceptibility to 20 common cancer types by a supervised machine-learning method

Prevention and early intervention are the most effective ways of avoiding or minimizing psychological, physical, and financial suffering from cancer. However, such proactive action requires the ability to predict the individual's susceptibility to cancer with a measure of probability. Of the triad of cancer-causing factors (inherited genomic susceptibility, environmental factors, and lifestyle factors), the inherited genomic component may be derivable from the recent public availability of a large body of whole-genome variation data. However, genome-wide association studies have so far showed limited success in predicting the inherited susceptibility to common cancers. We present here a multiple classification approach for predicting individuals' inherited genomic susceptibility to acquire the most likely phenotype among a panel of 20 major common cancer types plus 1 "healthy" type by application of a supervised machine-learning method under competing conditions among the cohorts of the 21 types. This approach suggests that, depending on the phenotypes of 5,919 individuals of "white" ethnic population in this study, (i) the portion of the cohort of a cancer type who acquired the observed type due to mostly inherited genomic susceptibility factors ranges from about 33 to 88% (or its corollary: the portion due to mostly environmental and lifestyle factors ranges from 12 to 67%), and (ii) on an individual level, the method also predicts individuals' inherited genomic susceptibility to acquire the other types ranked with associated probabilities. These probabilities may provide practical information for individuals, heath professionals, and health policymakers related to prevention and/or early intervention of cancer.

Urology pertinent neuroendocrine tumors: focusing on renal pelvis, bladder, prostate located sympathetic functional paragangliomas

Urology pertinent neuroendocrine neoplasias are more and more driving to research attractive contributions mainly as regards the urinary tract paragangliomas, besides the prostate cancer neuroendocrine differentiation. About such visceral sympathetic paragangliomas, a considerable attention is aroused by those concerning the renal pelvis, urinary bladder and, particularly, the prostate gland. Essential catecholamine/adrenergic signal-mediated pathophysiological implications and outlined diagnostic approaches are here taken into consideration. Particularly, to reach an accurate functional diagnostic assessment, both plasma and urine catecholamine level tests are required together with ¹²³I or ¹³¹I-meta-iodobenzylguanidine (MIBG) scan while ¹³¹I-, instead of ¹²³I-, labeled MIBG, proving to be also useful to targeted radionuclide therapy of sympathetic paragangliomas. Nevertheless, a thorough diagnostic confirmation should be obtained by a proper histologic/ immunohistochemical study, so that it respectively highlighting the typical "zellballen" cell setting and neuroendocrine tumor cell specific biomarkers such as chromogranin-A, synaptophysin, neuron-specific enolase. Open/laparoscopic/robot-assisted surgical procedures are performed under α1 (doxazosin, prazosin) - and β(propranolol)-adrenergic blockade to avoid the risk of an intraoperative adrenergic signal-triggered hypertensive crisis, what moreover may occur also during cystoscopy and biopsy in case of bladder or prostate paraganglioma. Given a conceivable likeness, about some adrenergic-mediated pathophysiological implications, between prostate paraganglioma and prostate cancer neuroendocrine transdifferentiation - although as regards two obviously different diseases - a reliable pathogenetic matter concerning prostate paraganglioma is requiring novel research approaches.