A. A. Aristov

Collective use center is an organization or structural unit with unique resource providing access to this resource for internal and third-party users. Collective use centers are a relatively new phenomenon in bioresource collections, especially collections of human biological material due to some ethical and legal issues. At the same time, the demand for human biological material continues to grow in fundamental and applied researches. The collective use center «Bioresource collection of tissues and cell cultures of tumors of the human nervous system for fundamental and applied researches» has worked since October 14, 2022. This center has access to unique collection of the Laboratory of Neurosurgical Anatomy and Conservation of Human Biological Tissues of the Burdenko Neurosurgical Center. Objective. To analyze the experience of collective use center and biobank of the Burdenko Neurosurgical Center compared to national and international data on functioning of collective use centers specializing in tumors of the human central nervous system. Material and methods. We reviewed the PubMed and e-Library databases using the following keywords: core facilities brain tumors, repository of collective use brain tumors, biobank of CNS tumors, central nervous system tumor collection centers. We also analyzed the organizations registered on the portal of scientific and technical infrastructure of the Russian Federation. Results. We analyzed 275 publications devoted to collective use centers and biobanks. These biobanks do not position themselves as collective use centers but actively realize biological material for researches. Structure of institutions presented on the portal of scientific and technical infrastructure of the Russian Federation is characterized. The collective use center «Bioresource collection of tissues and cell cultures of tumors of the human nervous system for fundamental and applied researches» has access to biobank of the Burdenko Neurosurgical Center. To date, the biobank contains more than 8478 aliquots of tumor tissue frozen at ultra-low temperature (–196°C) and obtained from 1993 patients. Considering available data, we established the basic principles of work in collective use centers with bioresource collections. Conclusion. Collective use centers with bioresource collections of tumors of the central nervous system are rare. There is only one collective use center organized at the Burdenko Neurosurgical Center on the portal of scientific and technical infrastructure of the Russian Federation. At the same time, there is an urgent need to increase their number and activity in Russia and other countries worldwide. You can use the resource of brain tumor collections by leaving a request on the official website of this organization in the «Collective use center» section.

The main problem in microsurgical resection of spinal cord tumors is excessive surgical aggression. The last one often leads to unsatisfactory clinical and neurological outcomes. Laser fluorescence spectroscopy is a modern neurosurgical approach to distinguish tumor boundaries even if standard visible fluorescence techniques are ineffective. Objective. To evaluate the effectiveness of laser fluorescence spectroscopy alone or in combination with visual 5-ALA fluorescence for improvement of safety and quality of resection, as well as intraoperative diagnosis. Material and methods. Searching for literature data was carried out in accordance with the PRISMA recommendations. The authors reviewed articles independently of each other. These data were systematized. Results. Laser fluorescence spectroscopy is valuable to identify fragments of intramedullary ependyomas in 86% of cases, while visual fluorescence only in 81% of cases. Advisability of this technique for low-grade astrocytomas is still unclear and requires further study. Its effectiveness is 87.5% for extramedullary meningiomas. Neuromas do not accumulate 5-ALA. In addition, this method can be used to determine the boundaries of intradural metastatic lesions. Conclusion. 5-ALA fluorescence is a safe and useful intraoperative method for identifying tumor tissue and resection margins in patients with intramedullary or infiltrative extramedullary spinal cord tumors. Visual fluorescence combined with laser spectroscopy is a perspective method for intraoperative visualization of tumor remnants. This approach can improve safety and postoperative outcomes while maintaining resection quality.

The authors present an extremely rare case of metastatic brain lesion in a patient with gastrointestinal stromal tumor of the stomach. There are literature data on 23 cases of metastatic lesions of the brain, skull and soft tissues of the head in similar patients. Atypical localization of metastases can lead to some diagnostic difficulties, unreasonable cancellation of chemotherapy and delayed surgical treatment. A feature of our observation was postoperative coma determined by the features of the underlying disease.

Introduction. Metabolic navigation with 5‑ALA is one of methods for intraoperative imaging in neuro‑oncology.Aim. To perform a comparative analysis of sensitivity of metabolic navigation with 5‑ALA during surgery of primary and secondary brain tumors of various histological nature and degree of malignancy.Materials and methods. During the period from 2013 to 2020, our group have performed surgery to 403 patients using metabolic navigation: microsurgical resections were performed in 384 people with brain tumors, 220 of them were with glial tumors, 101 were with intracranial meningiomas, 63 were with metastatic brain damage. Among patients with metastases, 39 patients had a solitary injury, 16 had a multi‑focal injury, so 72 cases of metastatic nodes were considered in this group. Stereotactic biopsies with 5‑ALA‑assistance were performed in 19 people. Metabolic navigation was performed with the drug 5‑ALA, which was taken orally at a dose of 20 mg/kg 2 hours before surgery. Intraoperative fluorescence was evaluated using microscope with a fluorescent module.Results. Metabolic navigation using microscope has a high sensitivity when employed during microsurgery (including repeated implementation of surgery) in cases of anaplastic gliomas (65 % in total, 58 % with bright glow), glioblastomas (94 % in total, 53 % with bright glow), intracranial meningiomas (94 % in total, 64 % – with bright glow). The use of 5‑ALA has significant limitations in sensitivity in cases of diffuse gliomas (46 % – in total, 27 % – with bright glow) and brain metastases (in total 87 % – for the solid part, 52 % – for the bed, with bright glow – 51 %). In diffuse gliomas, the glow areas had significantly higher proliferative index and cell nuclei density than the fluoronegative zones. Among the most important factors affecting the glow of gliomas it can be noted: the status of the IDH1 mutation, the volume of the contrasting part of the glioma according to MRI data, the methionine accumulation index according to positron emission tomography, the tumor blood flow indicators according to the arterial spin marking method – ASL perfusion.Conclusions. Implementation of 5‑ALA navigation with the use of microscope provides high sensitivity in cases of glioblastomas, anaplastic gliomas (especially for detecting of non‑contrasting part of tumor that is not visually altered in the white light of operating microscope) and brain meningiomas. The method is less effective in low‑grade gliomas and intracranial metastases.