Background: Neurofibromatosis type 1 (NF1) is a pheochromocytoma-associated syndrome. Because of the low prevalence of pheochromocytoma in NF1, we ascertained subjects by pheochromocytoma that also had NF1 in the hope of describing the germline NF1 mutational spectra of NF1-related pheochromocytoma. Materials and Methods: An international registry for NF1-pheochromocytomas was established. Mutation scanning was performed using denaturing HPLC for intragenic variation and quantitative PCR for large deletions. Loss-of-heterozygosity analysis using markers in and around NF1 was performed. Results: There were 37 eligible subjects (ages 14–70 yr). Of 21 patients with corresponding tumor available, 67% showed somatic loss of the nonmutated allele at the NF1 locus vs. 0 of 12 sporadic tumors (P = 0.0002). Overall, 86% of the 37 patients had exonic or splice site mutations, 14% large deletions or duplications; 79% of the mutations are novel. The cysteine-serine rich domain (CSR) was affected in 35% but the RAS GTPase activating protein domain (RGD) in only 13%. There did not appear to be an association between any clinical features, particularly pheochromocytoma presentation and severity, and NF1 mutation genotype. Conclusions: The germline NF1 mutational spectra comprise intragenic mutations and deletions in individuals with pheochromocytoma and NF1. NF1 mutations tended to cluster in the CSR over the RAS-GAP domain, suggesting that CSR plays a more prominent role in individuals with NF1-pheochromocytoma than in NF1 individuals without this tumor. Loss-of-heterozygosity of NF1 markers in NF1-related pheochromocytoma was significantly more frequent than in sporadic pheochromocytoma, providing further molecular evidence that pheochromocytoma is a true component of NF1.
Familial paraganglioma of the head and neck (HNP) has been a known entity for decades. Publications in 2000 and 2001 showed that mutations of the genes encoding the succinate dehydrogenase subunits B, C, and D, SDHB, SDHC, and SDHD, predispose to paraganglioma syndromes type 4, 3, and 1, respectively (PGL 1, PGL 3, PGL 4). PGL 1 tumors occurred only in offspring who inherited the mutation from the father, whereas PGL 3 and 4 are transmitted autosomal dominantly. We have established a national registry which was extended by cases from other countries for HNP in order to study the prevalence and clinical spectrum of SDHB, SDHC, and SDHD mutation carriers.
Introduction: Head and neck paragangliomas (HNP) may occur as sporadic as well as hereditary tumors. Three out of four paraganglioma syndromes (PGL) have been characterized on a molecular genetic basis since the year 2000. PGL 1 is associated with mutations of the succinate dehydrogenasis subunit D (SDHD) gene, PGL 3 is caused by SDHC, and PGL 4 by SDHB gene mutations.
Effective cancer prevention is based on accurate molecular diagnosis and results of genetic family screening, genotype-informed risk assessment, and tailored strategies for early diagnosis. The expanding etiology for hereditary pheochromocytomas and paragangliomas has recently included SDHA, TMEM127, MAX, and SDHAF2 as susceptibility genes. Clinical management guidelines for patients with germline mutations in these 4 newly included genes are lacking.To study the clinical spectra and age-related penetrance of individuals with mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes.This study analyzed the prospective, longitudinally followed up European-American-Asian Pheochromocytoma-Paraganglioma Registry for prevalence of SDHA, TMEM127, MAX, and SDHAF2 germline mutation carriers from 1993 to 2016. Genetic predictive testing and clinical investigation by imaging from neck to pelvis was offered to mutation-positive registrants and their relatives to clinically characterize the pheochromocytoma/paraganglioma diseases associated with mutations of the 4 new genes.Prevalence and spectra of germline mutations in the SDHA, TMEM127, MAX, and SDHAF2 genes were assessed. The clinical features of SDHA, TMEM127, MAX, and SDHAF2 disease were characterized.Of 972 unrelated registrants without mutations in the classic pheochromocytoma- and paraganglioma-associated genes (632 female [65.0%] and 340 male [35.0%]; age range, 8-80; mean [SD] age, 41.0 [13.3] years), 58 (6.0%) carried germline mutations of interest, including 29 SDHA, 20 TMEM127, 8 MAX, and 1 SDHAF2. Fifty-three of 58 patients (91%) had familial, multiple, extra-adrenal, and/or malignant tumors and/or were younger than 40 years. Newly uncovered are 7 of 63 (11%) malignant pheochromocytomas and paragangliomas in SDHA and TMEM127 disease. SDHA disease occurred as early as 8 years of age. Extra-adrenal tumors occurred in 28 mutation carriers (48%) and in 23 of 29 SDHA mutation carriers (79%), particularly with head and neck paraganglioma. MAX disease occurred almost exclusively in the adrenal glands with frequently bilateral tumors. Penetrance in the largest subset, SDHA carriers, was 39% at 40 years of age and is statistically different in index patients (45%) vs mutation-carrying relatives (13%; P < .001).The SDHA, TMEM127, MAX, and SDHAF2 genes may contribute to hereditary pheochromocytoma and paraganglioma. Genetic testing is recommended in patients at clinically high risk if the classic genes are mutation negative. Gene-specific prevention and/or early detection requires regular, systematic whole-body investigation.
The first description of pheochromocytoma in 1886 has been attributed to Felix Fränkel, who described an 18-year-old woman with bilateral adrenal "sarcoma and angio-sarcoma." We reviewed the publication and then approached and assessed relatives of the patient to update the findings with the use of current technology. In-depth review revealed that the histopathological findings were consistent with pheochromocytoma. Because the proband was young and had bilateral disease at diagnosis, we hypothesized that she had an inherited condition. The presence of germ-line RET mutations in four living relatives demonstrates that the original patient and her family had multiple endocrine neoplasia type 2 and provides molecular evidence that she had pheochromocytoma.
Randomised trials can provide high-level evidence to inform treatment decisions. Since their quality in respiratory medicine is largely unknown, we assessed the quality of a large set of chronic obstructive pulmonary disease (COPD) trials. As a marker of trial quality, we assessed the procedure and concealment of random allocation, and the conduct of an intention-to-treat-analysis in 344 randomised trials published between 1957 and 2006. We used ordered logistic regression to assess the association between trial quality and type of intervention, type of journal, journal impact factor and year of publication. 257 (75%) trials assessed pharmacological and 87 (25%) assessed nonpharmacological interventions. The generation of appropriate randomisation was reported in 27.0% of the trials, concealment of random allocation in 11.6% and an intention-to-treat analysis in 21.8% of trials. Significantly higher quality was found in trials on nonpharmacological interventions (OR 2.49, 95% CI 1.56-3.99), and in trials published in general medical journals (versus specialised journals; OR 2.25, 95% CI 1.30-3.90) and after 2000 (versus 1957-2000; OR 2.28, 95% CI 1.45-3.58). The association of quality with a high impact factor was of borderline significance (p = 0.06). The quality of many COPD trials is low but tends to become better since the adoption of the CONSORT (Consolidated Standards of Reporting Trials) statement.
Abstract Introduction Hemangioblastomas are rare, histologically benign, highly vascularized tumors of the brain, the spinal cord, and the retina, occurring sporadically or associated with the autosomal dominant inherited von Hippel-Lindau (VHL) disease. Children or adults with VHL disease have one of > 300 known germline mutations of the VHL gene located on chromosome 3. They are prone to develop hemangioblastomas, extremely rarely starting at age 6, rarely at age 12–18, and, typically and almost all, as adults. There is a plethora of VHL-associated tumors and cysts, mainly in the kidney, pancreas, adrenals, reproductive organs, and central nervous system. Due to a lack of causal treatment, alleviation of symptoms and prevention of permanent neurological deficits as well as malignant transformation are the main task. Paucity of data and the nonlinear course of tumor progression make management of pediatric VHL patients with hemangioblastomas challenging. Methods The Freiburg surveillance protocol was developed by combining data from the literature and our experience of examinations of > 300 VHL patients per year at our university VHL center. Results Key recommendations are to start screening of patients at risk by funduscopy with dilated pupils for retinal tumors with admission to school and with MRI of the brain and spinal cord at age 14, then continue biannually until age 18, with emergency MRI in case of neurological symptoms. Indication for surgery remains personalized and should be approved by an experienced VHL board, but we regard neurological symptoms, rapid tumor growth, or critically large tumor/cyst sizes as the key indications to remove hemangioblastomas. Since repeated surgery on hemangioblastomas in VHL patients is not rare, modern neurosurgical techniques should encompass microsurgery, neuronavigation, intraoperative neuromonitoring, fluorescein dye-based intraoperative angiography, intraoperative ultrasound, and minimally invasive approaches, preceded in selected cases by endovascular embolization. Highly specialized neurosurgeons are able to achieve a very low risk of permanent morbidity for the removal of hemangioblastomas from the cerebellum and spinal cord. Small retinal tumors of the peripheral retina can be treated by laser coagulation, larger tumors by cryocoagulation or brachytherapy. Conclusion We consider management at experienced VHL centers mandatory and careful surveillance and monitoring of asymptomatic lesions are required to prevent unnecessary operations and minimize morbidity.
