Physicians' awareness of gadolinium retention and MRI timing practices in the longitudinal management of pituitary tumors::a "Pituitary Society" survey

PURPOSE: In view of mounting attention related to possible brain retention of gadolinium-based contrast agents (GBCAs) in patients with normal renal function, our purpose was to detail results from a survey of pituitary experts to assess: 1) the timing interval and frequency of pituitary magnetic resonance imaging (MRI) following surgical and/or medical and/or radiation therapy of pituitary tumors, 2) awareness of the types of GBCAs used and their possible safety issues. METHODS: The Pituitary Society Education Committee composed a survey with 12 multiple choice questions, 8 of which specifically addressed the time interval and frequency of MRI in the longitudinal management of pituitary tumors. The survey was distributed at two meetings; the International Pituitary Neurosurgeons Society conference in San Diego, CA, on February 18th, 2018, and the Pituitary Society Membership and Career Development Forum, Chicago, IL on March 18th, 2018. RESULTS: There is consensus among pituitary endocrinologists and neurosurgeons that long-term repeated imaging is recommended in most pituitary tumors, although the precise strategy of timing varied depending on the specialist group and the specific clinical context of the adenoma. The data also suggest that International Pituitary Neurosurgeons Society neurosurgeons, as well as Pituitary Society neuroendocrinologists, are sometimes unaware of which contrast agents are used by their institution, and many are also unaware that evidence of long-term brain retention has been reported with the use of GBCAs in patients with normal function. CONCLUSIONS: International pituitary endocrinologists and pituitary neurosurgeons experts suggest ongoing MRIs for the management of pituitary tumors; strategies vary based on clinical context, but also on individual experience and practice

Temozolomide in aggressive pituitary adenomas and carcinomas

Temozolomide is an alkylating agent used in the treatment of gliomas and, more recently, aggressive pituitary adenomas and carcinomas. Temozolomide methylates DNA and, thereby, has antitumor effects. O6-methylguanine-DNA methyltransferase, a DNA repair enzyme, removes the alkylating adducts that are induced by temozolomide, thereby counteracting its effects. A Medline search for all of the available publications regarding the use of temozolomide for the treatment of pituitary tumors was performed. To date, 46 cases of adenohypophysial tumors that were treated with temozolomide, including 30 adenomas and 16 carcinomas, have been reported. Eighteen of the 30 (60%) adenomas and 11 of the 16 (69%) carcinomas responded favorably to treatment. One patient with multiple endocrine neoplasia type 1 and an aggressive prolactin-producing adenoma was also treated and demonstrated a good response. No significant complications have been attributed to temozolomide therapy. Thus, temozolomide is an effective treatment for the majority of aggressive adenomas and carcinomas. Evidence indicates that there is an inverse correlation between levels of O6-methylguanine-DNA methyltransferase immunoexpression and therapeutic response. Alternatively, high-level O6-methylguanine-DNA methyltransferase immunoexpression correlates with an unfavorable response. Here, we review the use of temozolomide for treating pituitary neoplasms

VI Curso Internacional de Endocrinología, Diabetes y Metabolismo

Diabetes en niños y adolescentes - no es solo diabetes tipo 1 o tipo 2 Ingrid Libman, Md, Phd La diabetes mellitus (DM) en la infancia y adolescencia constituye un espectro. Si bien la DM tipo 2 (DM2) es la forma más frecuente en la población en general, la DM tipo 1 (DM1) constituye el tipo más común en la niñez y juventud. Más del 50% de los enfermos afectados con DM1 son diagnosticados durante los primeros años de vida. En la mayoría de los países occidentales, la DM1 constituye más del 90% de los casos diagnosticados en la infancia y adolescencia. La DM2 era considerada hasta hace poco tiempo una enfermedad propia de la edad adulta. Si bien es cierto que continúa siendo más prevalente en este grupo etario, existe evidencia de su aparición con mayor frecuencia en la adolescencia y juventud, en estrecha asociación con el aumento en la prevalencia de la obesidad. La etiología de la DM2 es multifactorial, incluyendo factores genéticos y ambientales, resultando de la combinación de un aumento de la resistencia a la insulina en los tejidos periféricos asociado al incremento del tejido adiposo visceral y a una disfunción progresiva de las células ?. Por otra parte, una forma con características de ambos tipos, conocida como diabetes “doble” o “híbrida” ha sido descrita más recientemente, Estos jóvenes se presentan con un fenotipo que incluye manifestaciones de la DM2 (obesidad, presencia de acantosis nigricans) al mismo tiempo que muestran evidencia de autoinmunidad dirigida a las células ?, ya sea la presencia de anticuerpos o una respuesta anormal de los linfocitos a antígenos celulares de los islotes, indicadores de DM1

DICER1 gene mutations in endocrine tumors

In this review, the importance of theDICER1gene in the function of endocrine cells is discussed. There is conclusive evidence thatDICER1mutations play a crucial role in the development, progression, cell proliferation, therapeutic responsiveness and behavior of several endocrine tumors. We review the literature ofDICER1gene mutations in thyroid, parathyroid, pituitary, pineal gland, endocrine pancreas, paragangliomas, medullary, adrenocortical, ovarian and testicular tumors. Although significant progress has been made during the last few years, much more work is needed to fully understand the significance ofDICER1mutations.</jats:p

Spectroscopic indications of tunnel barrier charging as the switching mechanism in memristive devices

Resistive random access memory is a promising, energy-efficient, low-power “storage class memory” technology that has the potential to replace both flash storage and on-chip dynamic memory. While the most widely employed systems exhibit filamentary resistive switching, interface-type switching systems based on a tunable tunnel barrier are of increasing interest. They suffer less from the variability induced by the stochastic filament formation process and the choice of the tunnel barrier thickness offers the possibility to adapt the memory device current to the given circuit requirements. Heterostructures consisting of a yttria-stabilized zirconia (YSZ) tunnel barrier and a praseodymium calcium manganite (PCMO) layer are employed. Instead of spatially localized filaments, the resistive switching process occurs underneath the whole electrode. By employing a combination of electrical measurements, in operando hard X-ray photoelectron spectroscopy and electron energy loss spectroscopy, it is revealed that an exchange of oxygen ions between PCMO and YSZ causes an electrostatic modulation of the effective height of the YSZ tunnel barrier and is thereby the underlying mechanism for resistive switching in these devices

Electronic bandstructure of superconducting KTaO3 (111) interfaces

Two-dimensional electron gases(2DEGs)based on KTaO3 are emerging as a promising platform for spin-orbitronics due to their high Rashba spin-orbit coupling (SOC) and gate-voltage tunability. The recent discovery of a superconducting state in KTaO3 2DEGs now expands their potential towards topological superconductivity. Although the band structure of KTaO3 surfaces of various crystallographic orientations has already been mapped using angle-resolved photoemission spectroscopy(ARPES), this is not the case for superconducting KTaO3 2DEGs. Here, we reveal the electronic structure of superconducting 2DEGs based on KTaO3 (111) single crystals through ARPES measurements. We fit the data with a tight-binding model and compute the associated spin textures to bring insight into the SOC-driven physics of this fascinating system.Comment: 9 pages, 4 figure

Consenso nacional de expertos: definición de criterios diagnósticos, terapéuticos y de seguimiento de la enfermedad de Cushing en pacientes colombianos

Contexto: la enfermedad de Cushing es una enfermedad poco común en la población general, con una evolución clínica insidiosa, lo cual genera un reto para el diagnóstico oportuno a partir de la sospecha clínica. Al tener en cuenta el origen de la enfermedad, dado por la presencia de un tumor hipofisario secretor de la hormona adrenocorticótropa (ACTH); el tratamiento debe estar dirigido a lograr el control bioquímico y la resección de la masa tumoral. El seguimiento del paciente, orientado a vigilar el control de la enfermedad y detectar de forma temprana el desarrollo de comorbilidades, es un aspecto clave en el manejo adecuado de la enfermedad. Objetivo: definir criterios para el diagnóstico, el tratamiento y el seguimiento de la enfermedad de Cushing en pacientes colombianos. Metodología: se realizó un consenso tipo Delphi modificado con un grupo multidisciplinario de expertos en el manejo del paciente con enfermedad de Cushing (médicos endocrinólogos y neurocirujanos), donde la dirección del consenso fue realizada por un médico farmacólogo clínico. Los resultados fueron analizados y discutidos y, a partir de la consecución de consensos, se presenta una serie de recomendaciones en los diferentes apartados de la enfermedad de Cushing. Resultados: se generaron recomendaciones basadas en la opinión de expertos para el abordaje del paciente con enfermedad de Cushing, incluyendo los aspectos de sospecha clínica, diagnóstico bioquímico e imagenológico, tratamiento mediante intervención quirúrgica, alternativas de tratamiento farmacológico, radiocirugía y seguimiento del paciente. Conclusiones: en Colombia, es importante fortalecer el conocimiento médico desde la atención primaria hasta el especialista con alta experticia en temas como el correcto diagnóstico, el manejo y el seguimiento del paciente con enfermedad de Cushing para lograr la detección temprana de la enfermedad y disminuir la progresión de las comorbilidades asociadas

Pituitary society guidance: pituitary disease management and patient care recommendations during the COVID-19 pandemic—an international perspective

Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the viral strain that has caused the coronavirus disease 2019 (COVID-19) pandemic, has presented healthcare systems around the world with an unprecedented challenge. In locations with significant rates of viral transmission, social distancing measures and enforced ‘lockdowns’ are the new ‘norm’ as governments try to prevent healthcare services from being overwhelmed. However, with these measures have come important challenges for the delivery of existing services for other diseases and conditions. The clinical care of patients with pituitary disorders typically involves a multidisciplinary team, working in concert to deliver timely, often complex, disease investigation and management, including pituitary surgery. COVID-19 has brought about major disruption to such services, limiting access to care and opportunities for testing (both laboratory and radiological), and dramatically reducing the ability to safely undertake transsphenoidal surgery. In the absence of clinical trials to guide management of patients with pituitary disease during the COVID-19 pandemic, herein the Professional Education Committee of the Pituitary Society proposes guidance for continued safe management and care of this population

Pituitary Neoplasm Nomenclature Workshop: Does Adenoma Stand the Test of Time?

The WHO Classification of Endocrine Tumours designates pituitary neoplasms as adenomas. A proposed nomenclature change to pituitary neuroendocrine tumors (PitNETs) has been met with concern by some stakeholder groups. The Pituitary Society coordinated the Pituitary Neoplasm Nomenclature (PANOMEN) workshop to address the topic. Experts in pituitary developmental biology, pathology, neurosurgery, endocrinology, and oncology, including representatives nominated by the Endocrine Society, European Society of Endocrinology, European Neuroendocrine Association, Growth Hormone Research Society, and International Society of Pituitary Surgeons. Clinical epidemiology, disease phenotype, management, and prognosis of pituitary adenomas differ from that of most NETs. The vast majority of pituitary adenomas are benign and do not adversely impact life expectancy. A nomenclature change to PitNET does not address the main challenge of prognostic prediction, assigns an uncertain malignancy designation to benign pituitary adenomas, and may adversely affect patients. Due to pandemic restrictions, the workshop was conducted virtually, with audiovisual lectures and written précis on each topic provided to all participants. Feedback was collated and summarized by Content Chairs and discussed during a virtual writing meeting moderated by Session Chairs, which yielded an evidence-based draft document sent to all participants for review and approval. There is not yet a case for adopting the PitNET nomenclature. The PANOMEN Workshop recommends that the term adenoma be retained and that the topic be revisited as new evidence on pituitary neoplasm biology emerges

Pituitary society expert Delphi consensus: operative workflow in endoscopic transsphenoidal pituitary adenoma resection

Abstract: Purpose: Surgical workflow analysis seeks to systematically break down operations into hierarchal components. It facilitates education, training, and understanding of surgical variations. There are known educational demands and variations in surgical practice in endoscopic transsphenoidal approaches to pituitary adenomas. Through an iterative consensus process, we generated a surgical workflow reflective of contemporary surgical practice. Methods: A mixed-methods consensus process composed of a literature review and iterative Delphi surveys was carried out within the Pituitary Society. Each round of the survey was repeated until data saturation and > 90% consensus was reached. Results: There was a 100% response rate and no attrition across both Delphi rounds. Eighteen international expert panel members participated. An extensive workflow of 4 phases (nasal, sphenoid, sellar and closure) and 40 steps, with associated technical errors and adverse events, were agreed upon by 100% of panel members across rounds. Both core and case-specific or surgeon-specific variations in operative steps were captured. Conclusions: Through an international expert panel consensus, a workflow for the performance of endoscopic transsphenoidal pituitary adenoma resection has been generated. This workflow captures a wide range of contemporary operative practice. The agreed “core” steps will serve as a foundation for education, training, assessment and technological development (e.g. models and simulators). The “optional” steps highlight areas of heterogeneity of practice that will benefit from further research (e.g. methods of skull base repair). Further adjustments could be made to increase applicability around the world