Challenges in the determination of total vitamin B12 by cyanidation conversion: insights from stable isotope dilution assays.

Previous methods for vitamin B12 (B12) analysis have extensively used cyanidation conversion with the intention of converting all cobalamins to cyanocobalamin (CNCbl) for total B12 determination. This approach has been favored for its advantages in reducing the number of analytes, increasing analyte concentration, and improving analyte stability. However, the present study revealed underlying limitations associated with this approach. First, a stable isotope dilution assay (SIDA) determining total B12 as CNCbl after cyanidation conversion (conversion SIDA method) was developed. Method validation demonstrated good sensitivity, recovery, accuracy, and reproducibility for the target analyte CNCbl. However, subsequent application of the conversion method to real meat samples showed incomplete conversions of cobalamins. These inconsistencies revealed day-to-day variability and reliability challenges associated with the cyanidation process. It was not possible to identify this issue during method validation as CNCbl was spiked as the sole analyte and it requires no further cyanidation conversion. The application of LC-MS/MS enabled the detection of trace amounts of unconverted cobalamins. Nevertheless, this approach remains restricted by instrument sensitivity and stability as well as the performance of immunoaffinity purification for different vitamers. Further development of a reliable monitoring method is a prerequisite for further optimization of the cyanidation process. However, significant improvements of analytical instrumentation in terms of sensitivity and stability are required to overcome the current limitations.

How to develop new systemic treatments in ultra-rare cancers with high unmet needs? The case of alveolar soft-part sarcoma.

Developing new drugs or generating evidence for existing drugs in new indications for ultra-rare cancers is complex and carries a high-risk of failure. This gets even harder in ultra-rare tumours, which have an annual incidence of 1 per 1,000,000 population or less. Here, we illustrate the problem of adequate evidence generation in ultra-rare tumours, using Alveolar Soft-Part Sarcomas (ASPS) - an ultra-rare sarcoma newly diagnosed in approximately 60 persons a year in the European Union - as an exemplar case showing challenges in development despite being potentially relevant for classes of agents. We discuss some possible approaches for addressing such challenges, especially focussing on constructive collaboration between academic groups, patients and advocates, drug manufacturers, and regulators to optimise drug development in ultra-rare cancers. This article, written by various European stakeholders, proposes a way forward to ultimately get better options for patients with ultra-rare cancers.

What Is a Sarcoma 'Specialist Center'? Multidisciplinary Research Finds an Answer.

The management of sarcomas in specialist centers delivers significant benefits. In much of the world, specialists are not available, and the development of expertise is identified as a major need. However, the terms 'specialist' or 'expert' center are rarely defined. Our objective is to offer a definition for patient advocates and a tool for healthcare providers to underpin improving the care of people with sarcoma. SPAGN developed a discussion paper for a workshop at the SPAGN 2023 Conference, attended by 75 delegates. A presentation to the Connective Tissue Oncology Society (CTOS) and further discussion led to this paper. Core Principles were identified that underlie specialist sarcoma care. The primary Principle is the multi-disciplinary team discussing every patient, at first diagnosis and during treatment. Principles for optimal sarcoma management include accurate diagnosis followed by safe, high-quality treatment, with curative intent. These Principles are supplemented by Features describing areas of healthcare, professional involvement, and service provision and identifying further research and development needs. These allow for variations because of national or local policies and budgets. We propose the term 'Sarcoma Intelligent Specialist Network' to recognize expertise wherever it is found in the world. This provides a base for further discussion and local refinement.

The role of patient advocates and sarcoma community initiatives in musculoskeletal oncology. Moving towards Evidence-Based Advocacy to empower Evidence-Based Medicine.

Musculoskeletal sarcomas are rare cancers that as the whole family of sarcomas pose several challenges at different levels, ranging from medical knowledge to clinical research and policymaking. Addressing these challenges, necessarily calls for the inclusion of patient perspective inside the decision-making processes of every area that contributes to treatment improvement, from the provision of high-quality services by healthcare organisations to research issues. Without patient-provided inputs to inform decisions, the current paradigm of patient-centred care makes no sense and sounds at the least irrational if not unethical. Putting PROMs on "centre stage" in cancer research and care, could allow to build a truly Evidence Based Advocacy (EBA) and therefore to empower Evidence Based Medicine (EBM).

Best clinical management of tenosynovial giant cell tumour (TGCT): A consensus paper from the community of experts.

Tenosynovial giant cell tumour (TGCT) is a rare, locally aggressive, mesenchymal tumor arising from the joints, bursa and tendon sheaths. TGCT comprises a nodular- and a diffuse-type, with the former exhibiting mostly indolent course and the latter a locally aggressive behavior. Although usually not life-threatening, TGCT may cause chronic pain and adversely impact function and quality of life (QoL). CSFR1 inhibitors are effective with benefit on symptoms and QoL but are not available in most countries. The degree of uncertainty in selecting the most appropriate therapy and the lack of guidelines on the clinical management of TGCT make the adoption of new treatments inconsistent across the world, with suboptimal outcomes for patients. A global consensus meeting was organized in June 2022, involving experts from several disciplines and patient representatives from SPAGN to define the best evidence-based practice for the optimal approach to TGCT and generate the recommendations presented herein.

Global Patient Involvement in Sarcoma Care-A Collaborative Initiative of the Connective Tissue Oncology Society (CTOS) & Sarcoma Patients EuroNet (SPAEN).

Sarcomas are a grouping of rare cancers with a wide variety of histological types that are difficult to diagnose and treat. This leads to many varying challenges not only for sarcoma patients, but also for doctors, researchers, and caregivers. Patient advocacy groups have an important role to play in rare cancers such as sarcomas, especially in collaboration with experts and their medical societies. To this end, patients and patient advocates from Sarcoma Patients EuroNet (SPAEN), a global network of national Sarcoma Patient Advocacy Groups, and medical experts from the scientifically driven Connective Tissue Oncology Society (CTOS) came together on 9 November 2021 at an official ancillary event to the CTOS 2021 Annual Meeting. At the event, representatives of CTOS and SPAEN jointly discussed gaps and challenges in global sarcoma care and management. This resulting position paper highlights the main findings and possible future steps.

Unmet Medical Needs and Future Perspectives for Leiomyosarcoma Patients-A Position Paper from the National LeioMyoSarcoma Foundation (NLMSF) and Sarcoma Patients EuroNet (SPAEN).

As leiomyosarcoma patients are challenged by the development of metastatic disease, effective systemic therapies are the cornerstone of outcome. However, the overall activity of the currently available conventional systemic treatments and the prognosis of patients with advanced or metastatic disease are still poor, making the treatment of this patient group challenging. Therefore, in a joint effort together with patient networks and organizations, namely Sarcoma Patients EuroNet (SPAEN), the international network of sarcoma patients organizations, and the National LeioMyoSarcoma Foundation (NLMSF) in the United States, we aim to summarize state-of-the-art treatments for leiomyosarcoma patients in order to identify knowledge gaps and current unmet needs, thereby guiding the community to design innovative clinical trials and basic research and close these research gaps. This position paper arose from a leiomyosarcoma research meeting in October 2020 hosted by the NLMSF and SPAEN.

Identification of mutations in the lipoprotein lipase (LPL) and apolipoprotein C-II (APOC2) genes using denaturing high performance liquid chromatography (DHPLC).

BACKGROUND: Endothelial lipoprotein lipase (LPL) hydrolyzes triglycerides of chylomicrons and very low density lipoproteins, releasing free fatty acids for local and systemic use. Mutations in the LPL gene or its cofactor APOC2 may result in a decrease or complete loss of enzyme function and subsequently to type I hyperlipoproteinemia. METHODS: We used PCR to amplify all exons and the promoter region of LPL and APOC2. Nine blinded DNA samples with known LPL mutations were used as positive controls. In addition, nine patients from our lipid clinic and twelve healthy subjects were analyzed. DNA was screened for sequence variants by denaturing HPLC (DHPLC) followed by direct sequencing of PCR fragments showing distinct elution profiles. RESULTS: All LPL sequence variants in the positive controls (D9N, V69L, delAACTG386, I225T, N291S, and S447X) were correctly identified. In the remaining patients, additional variants were detected in LPL and APOC2. These variants were also present in healthy subjects, indicating that they constituted silent variation with no relevant effect on plasma triglycerides, at least in the heterozygous state. CONCLUSIONS: A semi-automated DHPLC screening method was developed for the detection of sequence variants in the LPL and APOC2 genes. Our results demonstrate that the method was robust and sensitive.