Search

The paper reports the analysis of the stereotactic irradiation outcomes in 430 patients with pilocytic astrocytomas (PAs), who underwent treatment in 2005–2018. The comprehensive approach to treatment of patients with intracranial pilocytic astrocytomas (PAs) that includes surgical removal, drug therapy (mostly in young children) and radiation therapy, is justified. The paper defines the roles of stereotactic radiosurgery and radiotherapy as the methods of choice used in the radiation therapy of patients with pilocytic astrocytomas. These methods show high conformity and selectivity, which is of special importance in patients with the PA localization in the functionally important structures.

The improvement of neuroimaging methods and introduction of the principles of microsurgery and radiosurgery involving the use of the Gamma Knife and CyberKnife systems into clinical practice have significantly changed the treatment outcomes in patients with metastatic brain tumors, thereby allowing to formulate new principles of treating this group of patients. The reported literature review summarizes the available treatment methods for patients with metastatic brain tumors with a focus on overall survival, local control, quality of life, and the capabilities of potential combinations of the existing treatment methods. The paper shows that personalized approaches to treatment of patients with brain metastases are optimal and improve the treatment outcomes.

Neurofibromatoses are a group of genetic disorders with predisposing for central and peripheral nervous system tumor development. The group includes three entities: neurofibromatosis type I, neurofibromatosis type II and schwannomatosis, which are characterized by gradual phenotype development and have a partially overlapping spectrum of manifestations, which complicates diagnosis establishing, especially at the stage of clinical onset. At the same time, the emergence of new pathogenetic therapy and the high risk of transmission to descendants actualize the necessity of early diagnosis. DNA tests allow us to reliably confirm the presumed diagnosis. This article presents a review of neurofibromatoses, their clinical features and courses, modern diagnostic criteria and indications for DNA tests.

The use of quantitative mapping of diffusion characteristics carries great potential for diagnosis and therapy of brain diseases, since it potentially allows to classify tumors, determine the degree of their malignancy, differentiate various morphological structures of tumor and non-tumor pathologies (such as tumor stroma, necrotic zones, cysts, various types of edema, etc.), and predict the course and outcome of diseases, in particular, a clinical response to treatment. Based on diffusion weighted magnetic resonance imaging (MRI), it is possible to perform 3D modeling of the white matter pathways of the brain, which is called tractography. In addition to a unique ability to visualize the location of tracts in relation to intracranial pathologies, this technology allows to build and analyze complex maps of communication networks in the brain (connectomics).The review is devoted to the discussion of the physical and technical concept of diffusion weighted MRI, the key ways of its application in tumor and non-tumor processes, and problems that complicate correct interpretation of results. Since the problem of developing software for diffusion MRI data remains relevant, this review presents our own experience in developing an application as part of a project on creating effective methods for processing diffusion MRI data and modeling white matter tracts.

External beam radiotherapy (EBR) remained for a long time the only method of treatment in children with recurrent and resistant retinoblastoma (RB). This method often leads to serious complications, including the occurrence of secondary malignant tumors. Currently, EBR is used as second-line (salvage) therapy. There is no data in the literature of using Gamma Knife stereotactic radiosurgery (GKRS) in RB treatment.Purpose. To present 5-year experience of using GKRS in patients with RB.Material and methods. 16 children (17 eyes) were treated using GKRS in the period from 2015 to 2019. Mean patient age was 34.7 months (range, 12–114 months). The eyes were classified as group B (n=4), C (n=1), D (n=12). 3 children had the last eye. All patients received systemic and local chemotherapy, all types of local treatment modalities before using GKRS. Recurrent and resistant RB was the indication for GKRS. Marginal 50% mean dose was 22 Gу (range, 20–24 Gу), depending on tumour type and location. Radiation doses were evaluated accounting critical eye structures and the orbit bones.Results. Complete regression was achieved in 11 patients, partial in 2. Four patients underwent enucleation after GKRS. Indications for enucleation were retinoblastoma recurrence (n=2) and vitreous hemorrhage with total retinal detachment (n=2). 13 eyes were salvaged with no signs of keratopathy, uveitis or damage of orbital and surrounding tissues during mean follow-up 30.6 months (range, 7–60 months). Сomplications of different severity occurred in 13 patients, including vitreous hemorrhage in 6 patients, which was successfully treated both conservative (n=3) and using pars plana vitrectomy with simultaneous melphalan irrigation (n=3).Conclusion. The first experience of GKRS as an alternative to enucleation in patients with RB was proved to be reasonable and successful.

The paper deals with the questions of introducing the additive technology of selective laser melting (SLM) into the production of the main structural elements of a combustion chamber for ground-based gas pumping, power and transport gas turbines. A fundamentally new design of a low-emission two-circuit burner was developed, adapted for the manufacture of products with a complex geometry through the use of selective laser melting (SLM) of metal powders according to mathematical CAD-models with the help of an advanced production technology. Technical difficulties associated with the implementation of additive manufacturing technology were overcome. The process chain was tried out from design to manufacturing and quality control of finished structural elements under conditions of mass production. The deficiencies of the parts manufactured by the additive technology were revealed and ultimately eliminated. Successful development of burners for a low-emission combustion chamber using a new technology significantly reduces labor intensity and time of production while maintaining high quality.

Background: Glioblastoma (GB) is the most commonly diagnosed brain tumor. Its management involves adjuvant therapies, such as radiation. The cause of high probability of GB local relapse is its radioresistance related to hypoxia arising from abnormal blood-brain barrier permeability in GB vessels and in the peritumoral zone (PZ).Aim: To study pathophysiology of hypoxia in the residual GB based on the abnormalities of the morphological elements of the capillary walls building up the blood-brain barrier in GB and PZ capillaries.Materials and methods: Samples for morphological evaluation were taken during surgery for GB in 5 patients. The samples were prepared for transmission electron microscopy according to the standard technique with fixation in 2% glutaraldehyde in phosphate buffer, post-fixation with osmium tetroxide, embedding in the epon-araldite mixture, and contrast staining of ultrathin sections with uranylacetate and lead citrate. Abnormalities of the capillary cells (mitochondrial vacuolization and vacuolization of endoplasmic reticulum in endothelial cells, pericytes and astrocytes), as well as of the acellular element of the capillary wall, i.e. basement membrane, were assessed in two groups of capillaries – those of GB (n = 38) and those of PZ (n = 32).Results: Abnormalities characteristic for apoptosis and oncosis were found in the cells of the GB and PZ capillaries of the blood-brain barrier, such as endothelial cells and pericytes. However, in the GB capillaries these abnormalities were signifcantly more frequent (р < 0.001). Only half (52.6%) of the GB capillaries had an edematous pericapillary astrocyte layer. In all other capillaries, astrocyte sprouts either were visualized as separate morphological elements (13.2%) or were not visualized at all (34.2%). All PZ capillaries had the astrocyte layer, being edematous in 68.8% of the capillaries and totally edematous only in 25%. Thickened basement membrane was found in the vast majority (89.5%) of the GB capillaries and only in 25% of the PZ capillaries (р < 0.001).Conclusion: Findings of abnormal cell elements in the GB capillaries leading to peritumoral edema and consequent hypoxia are highly likely to be the cause of the remnant GB radioresistance.

The study objective is to study overall survival and the rate of intracranial recurrences in patients with brain metastases after radiosurgery as single treatment.Materials and methods. The results of radiosurgical treatment of 579 patients with brain metastases (248 men and 331 women) were analyzed. The sources of brain metastases were breast cancer (164 patients), non-small-cell lung carcinoma (162), melanoma (123), kidney cancer (87), colorectal cancer (43). Median cumulative tumor volume, maximal lesion volume, number of brain metastases in the studied patient group were 5.4 cm3, 3.6 cm3, and 4, respectively. Mean marginal dose of ionizing radiation was 22 Gy (15–24 Gy). Mean follow-up duration was 13.4 months.Results. Overall survival of patients at 12 and 24 months was 42.8 and 24.8 %, respectively, with median overall survival after radiosurgery of 9.8 months (95 % confidence interval: 8.5–11.3). Local control of metastatic lesions was achieved in 81.3 % patients. Survival without local recurrence at 12 months was 66.7 %. Distant metastases developed in 235 (52.4 %) of 449 patients for whom radiological data was available. Survival without distant metastases at 12 and 24 months was 41.5 and 20.9 %, respectively. Multifactor analysis has shown that prognostic factors for long-term survival in patients with brain metastases were presence of breast cancer metastases in the brain, limited (4 lesions or less) number of brain metastases, high functional status, and absence of extracranial metastases. Increased survival duration was also associated with targeted therapy (p = 0.0412) and repeated radiosurgery to treat intracranial recurrences (р

Introduction. Surgical excision followed by whole-brain radiotherapy (WBRT) is a traditional treatment option for solitary brain metastases (SBM) of renal carcinoma. In the presence of multiple brain metastases of renal carcinoma WBRT remains to be the most common treatment option in this group of patients. However, the effectiveness of WBRT is insufficient due to radioresistance of renal carcinoma. After introduction of the standards in the radiosurgical practice, treatment options of renal carcinoma have been changed, since radiosurgery may overcome WBRT limitations in the treatment of brain metastases of radioresistant tumorsObjective: to study the effectiveness of stereotactic radiosurgery by using “Gamma Knife” device in the treatment of brain metastases of renal carcinoma.Materials and methods. We have analyzed results of the treatment of 112 patients with brain metastases of renal carcinoma who underwent radiosurgical treatment in Moscow Center “Gamma Knife”. Age median of the patients was 58 (33 –77) years. Total number of irradiated metastatic foci – 444, an average number of brain metastases in 1 patient was 4 (1–30). Twenty eight (25.0 %) patients had a single brain metastasis. A median of cumulative volume of brain metastases for each patient was 5.9 (0.1–29.1) cm3. An average value of the marginal dose for metastatic lesion was 22 (12–26) Gy, mean value of isodose used for treatment planning was 64 (39-99) %.Results. An overall survival (OS) rate after radiosurgical treatment was 37.7; 16.4 and 9.3 % for 12, 24 and 36 months, respectively. A median OS was 9.1 months (95% confidence interval (CI) 7.1–11.8). New brain metastases (distant recurrences) following radiosurgical treatment occurred in 44 (54.3 %) patients, with a median of 10.1 months (95 % CI:7-18). Local recurrences after radiosurgical treatment were detected in 19 (17 %) patients with a median time of 6.6 months (95 % CI 4.0–9.6). Factors associated with the best OS: Karnofsky score ≥ 80 (p

Development of stereotactic radiosurgery in ophthalmology started in the 1980s. Positive results in the Gamma-knife application were achieved in treatment of large uveal melanomas as an alternative for enucleation. The experience of Gamma-knife application inRussiais minimal.Purpose. To present the earliest results of treatment of patients with large uveal melanomas using the Gamma-knife radiosurgery.Material and methods. The study includes 7 patients with uveal melanoma (Т2-3N0M0) treated from June 2012 to December2013. Inall cases stereotactic radiosurgery was an alternative of eye enucleation and in 6 cases was a primary treatment. Irradiation was conducted according to the traditional planning technique irradiation with a 35-40 Gy by 50% isodose with maximum in tumor of 70-80 Gy. Follow-up was 2-18 months and in out-patients conditions.Results. The eyes and vision were preserved in 6 cases out of 7. Mean tumor regression was 2.8mm within more than 1 year. The main complication was radiation retinopathy of various manifestation.Conclusions. Gamma-knife radiosurgery allows to preserve the eyes with large uveal melanoma. Degree of radiogenic complications is not fatal for the eye. Nevertheless, a further follow-up is required for the treated patients to study possibilities of the method.

The paper describes the classification and treatment options of craniopharyngiomas, benign epithelial tumors arising from the cell remains of the Rathke’s pouch. It presents a few types of surgical accesses during surgical treatment for this disease and gives examples of how to place an Ommaya reservoir.

Piloid astrocytoma (PA) is a low-grade (WHO grade I) glial tumor that is more common in pediatric patients. According to the data of many authors, stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) promote long-term remission or delayed tumor progression in patients with inoperable tumors after incomplete removal of a tumor and with its recurrence. So it is urgent to determine the place and role of SRS and SRT in the combination treatment of patients with deeply located PA.Subjects and methods. In the period April 2005 to May 2010, the Department of Radiology and Radiosurgery, Neurosurgery Research Institute, Russian Academy of Medical Sciences, treated 101 patients diagnosed as having intracranial PA. Of them there were 70 children (aged 17 years inclusive) and 31 adults; 51 men and 50 women. The median age was 15.1 years (9.8 years for children and 28.7 years for adults). Tumor was histologically pre-verified in 90 (89.2 %) patients (tumor ablation in 83 cases and biopsy in 7). The diagnosis of PA was made on the basis of clinical and X-ray data in 11 (10.8 %) patients. ART was used in most cases (n = 66 (66.3 %)). SRS was performed in 35 (34.7 %) patients.Results. The median follow-up of the patients from the onset of disease was 52 months (range 2–228 months). Eighty-eight (87 %) patients could be followed up. On completion of the follow-up (December 2010), 87 (98.8%) of the 88 patients receiving SRT and SRS were alive. The median follow-up from the initiation of radiotherapy was 22.7 months (range 6–60 months). Tumors were enlarged in 20 (22.7 %) patients; those were due to cysts in 18. Eighteen patients were reoperated on. Histological specimens were examined and comparatively analyzed in 12 operated patients. The tumor changes accompanied by a reduction of the solid component and an increase of the cystic component were found to be a manifestation of tumor reactive-degenerative alterations as a consequence of radiation pathomorphi sm.Conclusion. SRT and SRS are effective treatments in patients with primary or recurrent PA irrespective of the tumor site and must be performed early after non-radical tumor removal. At present (median follow-up 22.7 months), tumor growth is controlled in 98 % of the

Piloid astrocytoma (PA) is a glioma that is most frequently encountered in children (WHO grade I). According to most authors, stereotactic radiation (radiotherapy and radiosurgery) is an effective method to control tumor growth in patients with incomplete removal of PA and its recurrence. The authors describe a clinical case of a female patient with PA of the midbrain; during the first 7 months after radiation she showed an obvious enlargement of the tumor, as evidenced by magnetic resonance imaging (MRI), with its further regression without any antitumor treatment. A follow-up of the patient and a regular evaluation of her clinical status and MRI changes, as compared to the similar clinical cases and literature data, may suggest that PA enlargement early after radiotherapy is generally pseudoprogression rather than true progression of the tumor. An understanding of this phenomenon will be able to improve the assessment of radiotherapy results in patients with PA and to rule out unnecessary antitumor treatment in this category of patients.

The accessibility of medical care plays important role in ensuring basic human needs and means unimpeded access to all services in national health care system. It is conditioned by: balance of necessary volumes of medical care of population, national medical and financial resources, availability and qualification of medical personnel, rendering of necessary types of medical care in territories, possibility of patient free choice of physician in charge and medical organization, available transport possibilities, level of public education on health promotion and diseases prevention. The availability of radiotherapy, as an integral part of oncological care, is determined by possibility of its timely delivery to all patients and is conditioned by total number of oncological centers equipped with radiotherapy equipment and qualified specialists. In this regard, availability of radiotherapy treatment is gradually introduced into priority state programs of health care modernization. The timely delivery of radiotherapy associated with increasing of numbers of oncology centers, improvement of their equipment and medical personnel staffing is crucial part of development strategy of state oncological care programs.

Craniopharyngioma (CP) is a benign epithelial tumor predominantly localized in chiasmatic-sellar region and third ventricle. There are two histological variants of CP: adamantinoma-like (ACP, 85%) and papillomatous (PCP). These types differ significantly in origin and histological structure. PCP predominantly occurs in adults. Treatment of CP, including effectiveness of radiotherapy, is described in multiple studies and mainly devoted to pediatric patients., Objective: To clarify disease-free survival in adults with newly diagnosed CP depending on resection quality; to evaluate the effectiveness of stereotactic irradiation and treatment depending on histological characteristics of tumor., Material and Methods: We analyzed treatment outcomes in 398 adults over 10-year follow-up. Stereotactic irradiation was performed in 11.6% of patients. The follow-up data were obtained in 68.1% of patients. We compared 5-year disease-free survival rates after different resections with and without subsequent irradiation., Results: Total resection is effective and provides significantly lower risk of CP recurrence. Effectiveness of stereotactic irradiation after incomplete resection was also confirmed., Conclusion: Total resection of ACP and PCP provides high disease-free survival rates. Stereotactic irradiation after incomplete resection is followed by similar outcomes. PCPs are characterized by less aggressive growth and do not recur after total resection.

Background: Stereotactic radiosurgery (SRS) for cerebral cavernous malformations has been used for more than 30 years. However, indications for this method and outcomes are still discussable., Objective: To analyze available literature data on SRS for cerebral cavernous malformations with assessment of indications for treatment, radiation parameters, radiological and clinical complications and outcomes., Results: The final analysis included 20 reports describing post-SRS outcomes in 1834 patients with cerebral cavernous malformations. The main radiation parameter was mean radiation dose to the edge of cavernous malformation (prescribed dose, 13.25±2.16 Gy). In natural course of malformation, mean incidence of hemorrhages from cavernous malformation when counted after the second hemorrhage was 25.9±14.6%, after the patient's birth - 2.59±0.44%. Mean follow-up period after SRS was 66.7±24.1 months. Incidence of hemorrhages from cavernous malformation after SRS for the first 2 years of follow-up was assessed in 14 studies (4.67±3.51%). Incidence of hemorrhages ≥2 years after SRS was analyzed in 12 studies (1.55±0.8%)., Conclusion: Despite significant global experience in SRS for cerebral cavernous malformations and many studies devoted to this problem, clear patient selection criteria have not yet been formulated. Modern selection principles have insufficient evidence base.

Primary brain metastases are common in oncology. Preoperative stereotactic radiosurgery followed by surgical resection is a perspective approach., Objective: To evaluate own experience of preoperative radiosurgery followed by surgical resection (RS+S) of metastasis regarding local control, leptomeningeal progression, surgical and radiation-induced complications; to compare treatment outcomes with surgical resection and subsequent radiotherapy (S+SRT)., Material and Methods. A: Retrospective study included 66 patients with solitary brain metastasis. Two groups of patients were distinguished: group 1 ( n =34) - postoperative irradiation, group 2 ( n =32) - preoperative irradiation. The median age was 49.5 years (range 36-75)., Results: Local 3-, 6- and 12-month control among patients with postoperative irradiation was 88.2%, 79.4% and 42.9%, in the group of preoperative irradiation - 100%, 93.3% and 66.7%, respectively ( p =0.021). Leptomeningeal progression developed in 11 patients (8 and 3 ones, respectively). The one-year survival rate was 73.5% and 84.4%, respectively ( p =0.33). Long-term surgical and radiation-induced complications occurred in 12 (18.2%) patients., Conclusion: Preoperative radiosurgery with subsequent resection provides higher local control and lower incidence of leptomeningeal progression in patients with single brain metastases.

Objective: To identify the characteristics of pain syndrome in patients with schwannomas depending on genetic predisposition., Material and Methods: The study included 46 patients with peripheral, spinal and intracranial schwannomas, corresponding to the schwannomatosis phenotype according to the 2022 clinical criteria. All patients underwent sequencing of the LZRT1 , Nf2 and SMARCB1 and a copy number study in the NF2 ., Results: The most severe widespread pain was observed in patients with pathogenic LZRT1 variants, while patients with mosaic variants may not even have local tumor-related pain. Patients with SMARCB1 variants may have no pain or have localized pain that responds well to surgical treatment., Conclusion: Further studies of the molecular features of schwannomatosis and driver mutations in the pathogenesis of pain are necessary to improve the effectiveness of pain therapy in this group of patients. Schwannomatosis is a disease from the group of neurofibromatosis, manifested by the development of multiple schwannomas. Neuropathic pain is one of the main symptoms characteristic of peripheral schwannomas, however, the severity and prevalence of the pain syndrome does not always correlate with the location of the tumors. According to modern concepts, the key factors influencing the characteristics of the pain syndrome are the target gene and the type of pathogenic variant. The most severe widespread pain is observed in patients with pathogenic variants in the LZRT1 gene, while patients with mosaic variants may not even have local pain associated with tumors. Patients with variants in SMARCB1 may have no pain or localized pain that responds well to surgical treatment.

Meningioma is the most common primary tumor of the central nervous system. Traditional classification is based on histological properties of tumors and distinguishes different grades of meningioma malignancy. However, knowledge about different molecular mechanisms of tumor provided new data on genetic features of meningiomas. The authors analyze current available data on the main driver mutations, new classifications based on molecular genetic characteristics and potential targets for therapy.

Treatment of craniovertebral junction meningioma is a difficult task. Surgical treatment is the gold standard for these patients. However, it is associated with high risk of neurological impairment, while combined treatment (surgery + radiotherapy) provides more favorable outcomes., Objective: To present the results of surgical and combined treatment of patients with craniovertebral junction meningioma., Material and Methods: There were 196 patients with craniovertebral junction meningioma who underwent surgical or combined (surgery + radiotherapy) treatment at the Burdenko Neurosurgery Center between January 2005 and June 2022. The sample included 151 women and 45 men (3.4:1). Resection of tumor was performed in 97.4% of patients, craniovertebral junction decompression with dural defect closure - 2%, ventriculoperitoneostomy - 0.5%. As the second stage, 40 patients (20.4%) underwent radiotherapy., Results: Total resection was achieved in 106 patients (55.2%), subtotal - 63 (32.8%), partial - 20 (10.4%), tumor biopsy was performed in 3 (1.6%) cases. Intraoperative complications occurred in 8 patients (4%), postoperative complications - in 19 (9.7%) cases. Radiosurgery was carried out in 6 (15%) patients, hypofractionated irradiation - 15 (37.5%), standard fractionation - 19 (47.5%) patients. Tumor growth control after combined treatment made up 84%., Conclusion: Clinical outcomes in patients with craniovertebral junction meningioma depend on tumor dimensions, topographic and anatomical localization of tumor, resection quality and relationship with surrounding structures. Combined treatment of anterior and anterolateral meningiomas of the craniovertebral junction is preferable compared to total resection.

Introduction: Stereotactic radiosurgery is one of the main treatments for vestibular schwannomas (VS). Their feature is frequent post-radiation pseudoprogression. This may be due to hormonal status of patients., Objective: To analyze expression of progesterone and estrogen receptors in women and men with VS., Material and Methods: Immunohistochemical analysis of expression of progesterone (PR) and estrogen receptors (ER) after biopsy was performed in 240 patients with VS between 2018 and 2021. ER/PR expression was assessed in men ( n =120) and women ( n =120) in 3 age subgroups: young age (18-44 years), middle age (45-59 years) and old age (60-79 years). Each subgroup included 40 patients. Statistical analysis was performed using the Mann-Whitney test and MedCalc software., Results: ER expression is not typical for VS (men - 1 (0.01%), women - 3 (2.5%)). At the same time, PR expression was found in 29 (24.2%) men and 21 (17.5%) women. We found no significant difference in expression of ER and PR between men and women. However, variability in PR expression was revealed, i.e. predominance of this indicator in young women ( p =0.0463) and middle-aged men ( p =0.0110). Expression of PR was similar in elderly patients ( p =0.2382)., Conclusion: The established incidence of PR expression may be one of the probable causes affecting development and duration of VS pseudoprogression after radiosurgery without clear relationship between sex and age. Further prospective research is needed to predict the risks of pseudoprogression.

Schwannomatoses is a new classification unit for all the hereditary diseases caused by chromosome 22 damage followed by multiple benign neoplasms of the peripheral and central nervous system. Schwannomatosis occurs as a result of damage to different genes: NF2, SMARCB1, LZRT1, loss of heterozygosity of the long arm of chromosome 22. Nevertheless, clinical manifestations are similar. Molecular diagnostics not only confirms the diagnosis, but also predicts the course of disease. Thus, the most severe clinical manifestations are observed in patients with violation of semantic sequences and reading frame shift in exons 2-13 of the NF2 gene. A more favorable course with less number of tumors is observed in patients with somatic mosaicism. Stereotactic irradiation and surgery are the main treatment options for schwannomatosis. However, there is evidence of effective targeted therapy with bevacizumab (inhibitor of vascular endothelial growth factor). Bevacizumab is used in patients with bilateral vestibular schwannomas and high risk of hearing loss, as well as for intramedullary tumor growth control.

Hemangioblastoma is a benign tumor of the central nervous system arising sporadically or as a component of Von Hippel-Lindau disease. Von Hippel-Lindau disease is a rare autosomal dominant hereditary syndrome with various phenotypes caused by VHL gene variants. To date, only about 40 cases of optic nerve hemangioblastoma have been described in the literature. Stereotactic irradiation may be effective for supratentorial hemangioblastomas including lesions of optic nerves. The authors describe a rare case of stereotactic irradiation of intraorbital hemangioblastoma of the optic nerve in a patient with Von Hippel-Lindau disease.

Post-resection or isolated hypofractionated stereotactic radiotherapy (HF-SRT) is a therapeutic option for large brain metastases (>2 cm, LBMs)., Objective: To compare the results of post-resection or isolated HF-SRT in patients with LBMs., Material and Methods: A prospective study included 115 patients with 129 intact LBMs and 133 patients with 149 resected LBMs who underwent HF-SRT. Median baseline focal size was 22.5 and 28 mm, median target volume - 8.3 and 23.7 cm 3 , respectively., Results: Median follow-up was 13.9 months, median overall survival - 19.1 months. After 12 months, local recurrences developed in 17 and 31% of patients, respectively ( p =0.0078). Local recurrence after 12 months developed in 23% of patients with residual tumor in postoperative cavity compared to 16% of patients after total resection ( p =0.0073). After 12 months, incidence of leptomeningeal progression was 27 and 11%, respectively ( p =0.033), incidence of symptomatic radiation-induced necrosis - 4 and 23%, respectively ( p =0.0006)., Conclusion: Post-resection HF-SRT demonstrated better local control and less severe symptomatic radiation-induced necrosis compared to patients with intact LBMs. Incidence of leptomeningeal progression is significantly higher after resection of LBMs.

There are various approaches to the treatment of patients with parasagittal meningiomas., Objective: To optimize treatment strategy for meningiomas invading the superior sagittal sinus., Material and Methods: The study included 87 patients with benign parasagittal meningiomas between 2010 and 2012. Of these, 34 patients underwent surgery alone, 27 - radiotherapy, 26 - surgery and subsequent radiotherapy. Both groups were comparable in male-to-female ratio, age and localization of tumors in relation to superior sagittal sinus. The follow-up period was at least 5 years. We analyzed the effect of treatment on neurological status, Karnofsky score and tumor growth control., Results: Mean volume of tumors was 43.3 cm 3 in patients undergoing surgery and 6.7 cm 3 in the radiotherapy group. In the combined treatment group, mean volume was 65.8 cm 3 before surgery and 8.8 cm 3 before irradiation. General cerebral symptoms (84%), epileptic seizures (37%) and movement disorders (31%) prevailed. Surgery provided the best results in patients with small meningiomas (<14 cm 3 ) causing focal neurological symptoms. Isolated radiotherapy was the most effective in asymptomatic patients. Large tumors required surgery with adjuvant irradiation., Conclusion: Benign parasagittal meningiomas followed by focal neurological symptoms require surgical intervention regarding the best functional outcomes and tumor growth control. Radiotherapy without surgery is advisable for progressive asymptomatic tumors. Resection followed by irradiation is preferable if total resection without the risk of damage to veins and cortex is impossible.

Using the example of a recurrent tumor with a 10-year follow-up, the authors show that mutation of the IDH1/2 genes in astrocytomas is not always an early event in the pathogenesis of glioma, that in rare cases a 1p19q codeletion can be found in astrocytomas, and that IDH-mutant tumors can occur in childhood.

Hypothalamic hamartoma (HH) is a dysplastic lesion fused with hypothalamus and followed by epilepsy, precocious puberty and behavioral disorders. Up to 50% of patients become free of seizures after surgery, but various complications occur in 1/4 of cases. Radiofrequency thermocoagulation, laser interstitial thermal therapy and stereotactic radiosurgery (SRS) are alternative treatment options., Objective: To define the indications for SRS in patients with HH and to clarify the irradiation parameters., Material and Methods: Twenty-two patients with HH and epilepsy underwent SRS at the Moscow Gamma-knife Center. A retrospective analysis included 19 patients with sufficient follow-up data. Median age of patients was 11.5 years (range 1.3-25.8). The diameter of irradiated HHs ranged between 5.5 and 40.9 mm. In 8 (36%) cases, the volume of hamartoma exceeded 3 cm 3 . Mean prescribed dose was 18±2.0 Gy, mean prescribed isodose - 48±4.2%. Median follow-up period was 14.8 months (range 3.4 - 96.1)., Results: Three (15.8%) patients were free of seizures. One patient (5.3%) improved dramatically after treatment with compete resolution of generalized seizures and experienced only rare emotional seizures (Engel IB). Eleven (57.8%) patients reported lower incidence of seizures. Severity and incidence of seizures were the same in 4 patients (21.1%). The best results were achieved in mean target dose over 20-22 Gy, minimal target dose over 7-10 Gy, covering by the prescribed dose of at least 70-80% of hamartoma volume, as well as in patients with the prescribed dose of 12 Gy delivered to almost entire volume of tumor. None patient had any complications after SRS., Conclusion: SRS is safe regarding neurological, endocrine or visual disturbances. Careful patient selection for SRS makes it an effective option for HH-related epilepsy. The best candidates for SRS are children with seizures aged over 1 year, hamartoma <3 cm 3 and area of fusion with hypothalamus <150 mm 2 .

Optic nerve glioma is a rather rare tumor. It predominantly arises in pediatric patients, including those with type I neurofibromatosis. This neoplasm is accompanied by decreased visual function and exophthalmos. Treatment strategy is individualized depending on age, volume and spread of tumor, as well as severity of clinical manifestations. Possible treatment options are surgical resection, chemotherapy, radiotherapy and their combination. Radiotherapy can be recommended for patients with intact visual functions, no severe proptosis and trophic lesions. Classic fractionation mode is used as a standard. Currently, the possibility of hypofractionated irradiation is being considered., Objective: To evaluate safety and efficacy of hypofractionated radiotherapy in patients with optic nerve glioma., Material and Methods: Sixteen patients with optic nerve gliomas underwent hypofractionated stereotactic irradiation (CyberKnife) between May 2014 and October 2019. Single focal dose was 5.5 Gy. There were 5 fractions up to total focal dose of 27.5 Gy. The sample enrolled 14 children with a median age of 4 years (range 23 months - 13 years) and 2 adults aged 47 and 66 years, respectively. Median of tumor volume was 2.77 cm 3 (range 1.69-10.01 cm 3 )., Results: Tumor growth control was achieved in all patients, partial remission was observed in 5 (32%) patients. None patient had deterioration of visual function. Improvement of visual acuity was noted in 3 (19%) cases. Visual field enlargement occurred in 4 (67%) out of 6 patients who were preoperatively examined. After irradiation, proptosis decreased by ≥ 1 mm in 9 (60%) out of 15 patients.

Optic nerve sheath meningioma (ONSM) is a slow-growing benign tumor that tends to extend intracranially. The tumor is characterized by vision disturbance, optic nerve atrophy and edema. At present, radiotherapy is recommended as the treatment of choice for ONSM., Purpose: To assess the neuro-ophthalmic symptomatology of ONSM and how it changes in response to radiotherapy., Material and Methods: In the period from 2004 to 2018, 112 patients with ONSM aged 17 to 76 years underwent stereotactic radiotherapy. In 91 patients, visual functions varied from light perception to 1.0; in 21 patients the affected eye was blind. The prospective follow-up of 103 patients lasted 6 months to 10 years (mean follow-up duration was 57 months). Studied patients underwent either conventional fractionated radiotherapy with Novalis ( n =88) or hypofractionation radiotherapy with CyberKnife ( n =24)., Results: According to ophthalmological examination, in 60.5% of cases an improvement of visual functions was observed, 39.5% of patients had visual functions remain stable at the initial level. No vision impairment during irradiation was detected. Vision deterioration in the long-term follow-up was observed in 2 patients: extended tumor growth in one case and radio-induced retinopathy in the other., Conclusion: The study showed that this method of treatment for ONSM is effective and safe, allowing preservation of visual functions and in some cases - its improvement, while tumor growth remains under control.

Stereotactic radiosurgery of vestibular schwannoma is an effective and safe method of treatment. The phenomenon of schwannoma pseudo-progression (transient post-radiation enlargement) complicates assessment of the outcomes after radiosurgery., Objective: To investigate the changes of vestibular schwannoma in different periods after radiosurgery., Material and Methods: We analyzed early and long-term radiation-induced changes in 333 patients who received Gamma Knife treatment at the Burdenko Neurosurgery Center between April 2005 and December 2015. Mean follow-up period was 60 months (range 15-167). There were 89 men (26.7%) and 244 (73.4%) women. Mean age of patients was 48.2 years. Mean baseline tumor volume was 4.1 cm 3 (range 0.1-14.5). Dynamics of changes was assessed using volumetric comparison., Results: Tumor shrinkage without pseudo-progression was observed in 149 (44.7%) patients. Typical pseudo-progression in different variants was found in 131 (39.3%) patients, i.e. short-term (1 year) and long-term (≥2 years) course, complete and incomplete process. Eleven patients had atypical pseudo-progression after initial tumor shrinkage. Progression-free 5- and 10-year survival in the entire group was 87 and 81%, respectively. Progression-free 5-year survival rate was 95 and 92% in patients with and without pseudo-progression, respectively. Ten-year survival rate was 89 and 89%, respectively., Conclusion: Knowledge of pseudo-progression features is essential for the most reasonable and reliable assessment of treatment results and justification of timing and frequency of subsequent MR control. Atypical course of pseudo-progression can simulate tumor recurrence. In case of tumor enlargement at any follow-up stage after radiosurgery, advisability of surgery should be determined considering clinical data and likelihood of tumor shrinkage following natural regression of post-radiation tumor enlargement.

Glioblastoma (GB) is one of the most aggressive primary brain tumors. Analysis of molecular genetic factors affecting prognosis in patients with GB is an important direction of fundamental and clinical researches. There are literature data on the effect of TERT gene mutations, MGMT methylation and IDH1/2 status on overall survival in patients with GB., Objective: To evaluate the incidence of TERT gene promoter mutations in adults with primary GB and to analyze the effect of TERT mutations on relapse-free and overall survival, as well as interaction of these mutations with MGMT gene methylation and IDH1/2 mutations., Material and Methods: The study included 56 patients (26 women and 30 men) with histologically verified GB in which genetic and molecular investigations were performed. There were patients with life duration >3 years ( n =15) and people with an extremely unfavorable course of disease (14 ones with primary multiple GB, 8 patients with GB metastases including extraaxial and 8 patients with life duration <8 months). TERT gene sequencingwas performed in all the cases, IDH1/2 status was known for 41 patients, MGMT status - for 23 patients., Results: Overall survival significantly differed between patients with and without TERT mutation (56 vs 17 months, p >0.05). TERT gene promoter mutation increased the effect of IDH1/2 mutations on overall and relapse-free survival ( p =0.011). No TERT and IDH1/2 gene mutations worsened prognosis. There were no significant differences between TERT status and development of primary multiple GBs, as well as extra- and intracranial metastases., Conclusion: Thus, the combined status of IDH1/2 and TERT mutations was a factor of better prognosis and can be proposed in clinical practice.

To date, no modern methods of treatment allow overcoming malignant potential of glial neoplasms and significant increase of survival. Analysis of glioblastoma radioresistance using cancer cell cultures is one of the perspective directions, as radiotherapy is standard and available treatment method for these neoplasms. This review summarizes current studies identifying many factors of radioresistance of glial tumors, such as hypoxia, microenvironment and metabolic features of tumor, stem cells, internal heterogeneity of tumor, microRNA, features of cell cycle, DNA damage and reparation. We obtained data on involvement of various molecular pathways in development of radioresistance such as MEK/ERK, c-MYC, PI3K/Akt, PTEN, Wnt, JAK/STAT, Notch, etc. Changes in activity of RAD51 APC, FZD1, LEF1, TCF4, WISP1, p53 and many others are determined in radioresistant cells. Further study of radioresistance pathways will allow development of specific target aptamers and inhibitors.

Identification of specific alterations in tumors (as a rule, these are mutations or gene fusions) makes it possible to prescribe targeted drugs of the second line of therapy or, in some cases of inoperable tumors, to observe not only a gradual partial response of the tumor to treatment, but also the removal of these patients from the category of incurable ones. The article describes a new rare type of BRAF::EPB41L2 gene fusion detected in a piloid astrocytoma that developed in the posterior cranial fossa in an 11-year-old boy.

Introduction: Stereotactic method and new irradiation techniques ensured radiosurgical treatment with high precision and conformity and significantly expanded the indications for stereotactic irradiation in neurosurgery., Material and Methods: Over 15-year period, 29 976 patients underwent irradiation in various modes of fractionation on linear accelerators and Gamma Knife system at the first national radiosurgery center., Results: Stereotactic radiotherapy and radiosurgery are followed by minimal number of complications and side reactions. At the same time, 5-year control of tumor growth for skull base meningioma was 96.8%, neuroma - 97%, glomus tumor - 94%, pituitary adenoma - 96-98%, craniopharyngioma - 95% in overall 10-year survival 86%, pilocytic astrocytoma - 97.5% in overall 5-year survival 99%. In intracranial metastases, median overall survival after radiosurgery was 10.1 months, 24- and 36-month overall survival - 25.9% and 19.2%, respectively. In patients with recurrent high-grade glioma, overall survival was 27.4 months. In case of metastatic spine lesions, control of tumor growth within 1 year was achieved in 90% of patients, pain relief - in more than 50% of cases. Obliteration of AVM and dural fistula was found in more than 80% of patients in years after treatment. Reduction or disappearance of pain was also observed in 80% of patients with trigeminal neuralgia., Conclusion: Stereotactic irradiation is effective and safe in patients with various pathologies of the central nervous system and characterized by high socio-economic indicators. Our own data indicate more significant role of stereotactic irradiation in the treatment of neurosurgical patients and make it possible to revise the existing treatment standards.

Background: Despite the combined treatment in accordance with modern standards, recurrent glioblastoma usually occurs within several months after resection and causes low relapse-free and overall survival. One of the most effective methods for malignant glioma progression is repeated radiotherapy. Indications for this approach have expanded after introduction of stereotactic irradiation into routine clinical practice., Objective: To evaluate the results of radiosurgery in patients with recurrent glioblastoma and to identify the factors determining its effectiveness., Material and Methods: Radiosurgery has been carried out in 168 patients with relapses of glioblastoma between 2005 and 2021. This study enrolled 88 patients with 180 foci of local and distant progression. Mean age of patients was 42.8±2.1 years (range 4-73). Mean period between diagnosis and repeated irradiation was 12.7 months. Mean volume of focus was 2.4 cm 3 , mean dose - 20 Gy. Median follow-up period after radiosurgery was 11.2 months., Results: Repeated irradiation with correction of systemic therapy improved progression-free survival and overall survival with insignificant radiation-induced toxicity. Annual overall survival was 62.2%, median of overall survival after radiosurgery - 15.1 months. Significant factors of local control were marginal dose of at least 18 Gy and distant relapse. Median of progression-free survival in the group of distant progression of glioblastoma was only 3.6 months vs. 9.1 months in patients with local recurrence., Conclusion: Repeated irradiation in radiosurgery mode with a dose of 18 Gy and higher is an effective option for local treatment increasing progression-free and overall survival in patients with progression of glioblastoma.

Central neurocytoma is a rare benign brain tumor. These tumors may be giant and accompanied by compression of ventricular system and surrounding structures. Modern treatment of brain neurocytoma includes extended resection and restoration of normal CSF circulation. Surgical treatment does not often lead to total resection of these tumors. Redo resection was preferred in patients with tumor progression for a long time. In the last decade, various authors report stereotactic irradiation for continued tumor growth to ensure local growth control. This study was aimed at evaluation of postoperative outcomes in patients with brain neurocytomas, as well as treatment of tumor progression in long-term period., Objective: To analyze recurrence-free survival in patients with brain neurocytomas, risk factors of recurrence-free survival, effectiveness of various treatments for tumor progression and delayed complications., Material and Methods: Long-term postoperative follow-up data of patients with brain neurocytomas are reported in the manuscript. We analyzed recurrence-free survival and risk factors of recurrence-free survival, treatment outcomes in patients with progression of brain neurocytomas, long-term complications and their prevention., Results: Follow-up included 84 out of 115 patients with brain neurocytoma after surgical treatment in 2008-2017. Follow-up period ranged from 2 to 10 years (mean 6 years) after resection. Most patients had regression of neurological symptoms after surgery. Continued tumor growth within 12-96 months after surgery occurred in 26 (30.19%) out of 84 patients (19 cases after partial resection and 7 cases after total resection according to MRI data). Two-year recurrence-free survival was 94%, 5-year survival - 83%. Risk factors of continued tumor growth were resection quality and Ki-67 index. Redo resection was performed in 7 cases. Eleven patients underwent stereotactic irradiation for tumor progression. Indications for stereotactic irradiation of central neurocytoma are MR data on continued growth of lateral ventricle tumor without signs of ICH and CSF flow impairment. There were no cases of hemorrhage inside the residual tumor and CSF flow impairment in early postoperative period after redo resection. In all cases ( n =11), stereotactic irradiation (mean follow-up 2.5 years) ensured satisfactory control of tumor growth with reduction of the neoplasm in 4 cases and no tumor growth in 7 cases., Conclusion: Resection of central neurocytoma ensures long-term recurrence-free period. The main causes of tumor recurrence are partial resection and high proliferative activity (Ki-67 index over 5%). Redo resection is advisable for tumor progression followed by CSF flow impairment. In case of continued growth of neurocytoma without signs of intracranial hypertension, stereotactic irradiation with various fractionation modes ensures effective and safe control of tumor growth.

Complex management of patients with intracranial pilocytic astrocytoma (PA) consists of surgical treatment, drug therapy (mainly in young children) and radiotherapy. For many years, radiotherapy (RT) has been a standard for residual tumors, recurrence or continued growth of PA. Currently, stereotactic radiosurgery and radiotherapy are preferred for PA, because these procedures are characterized by high conformity and selectivity, precise irradiation of tumor with minimal damage to surrounding intact tissues. Stereotaxic approach is very important since PAs are localized near functionally significant and radiosensitive brain structures in most cases. There is significant experience of single-center studies devoted to radiotherapy of patients with PA at the Department of Neuroradiosurgery of the Burdenko Neurosurgery Center. In this research, the authors analyzed the results of stereotactic irradiation of 430 patients with PA for the period from 2005 to 2018.

Glioma metastasis outside the central nervous system is a quite rare phenomenon. The disease in a young woman manifested itself as back pain and loss of vision in the left eye. Magnetic resonance imaging (MRI) revealed a tumor of the optic nerve; positron emission tomography showed multiple secondary bone changes. At the same time, MRI detected no signs of neoplasm in the midline brain structures (the brain stem and subcortical nuclei) and spinal cord. Two biopsies (superior iliac spine trephine biopsy and optic nerve tumor biopsy) were performed. There were similar histological tumors; the optic nerve tumor was found to have K27M mutation in the H3F3A gene, whereas the metastatic tumor lacked this mutation (possibly due to the quality and quantity of DNA isolated from the tumor cells). The interesting features of this case are the simultaneous detection of primary and metastatic tumors before receiving any treatment and the absence of the K27M mutation in the H3F3A gene in the metastasis.

Undefined: Cerebral arteriovenous malformations (AVM) are increasingly detected in children., Objective: To estimate the risk of hemorrhage in children with AVM before and after treatment and evaluate the outcomes of various methods of AVM management in children., Material and Methods: This study included 376 patients with various cerebral AVM under the age of 18 years. There were 273 patients with intracranial hemorrhage (72.6%)., Results: Recurrent hemorrhages within the first month were registered in 1.1% of patients with angiomatous AVM prior to treatment and in 15.4% of patients with fistulous AVM. Microsurgical resection of AVM was performed in 135 (35.9%) patients. Total resection was achieved in 97.8% of cases. There were no mortality after microsurgical procedures. Endovascular treatment was applied in 79 (21%) patients. Total embolization was achieved in 29.1% of patients. One patient (1.3%) died after endovascular procedure. Radiosurgery was performed in 140 (37.2%) patients with total obliteration after a single fraction in 64.4% of patients. Favorable long-term outcomes (GOS grades V-IV) were achieved in 89.6% of patients with available follow-up data (n=182). Recurrent hemorrhages were registered in 6% of patients (3.3% after radiosurgery, 2.7% after endovascular treatment). One patient with recurrent hemorrhage died after radiosurgery., Conclusion: Early relapses of hemorrhage are not characteristic for children with cerebral AVM. Therefore, there are no indications for urgent surgery except for cases of intracerebral hematoma. In children, microsurgical treatment is preferred for angiomatous AVM, endovascular treatment - for fistulous AVM. Radiosurgery also ensures favorable outcomes. However, it is unreasonable to postpone AVM radiosurgical treatment in children with increased risk of recurrent hemorrhage considering relatively long period of post-radiation obliteration of AVM.

Medulloblastoma (MB) is the most common brain malignancy in children occurring in the posterior cranial fossa. This tumor is characterized by high risk of metastasis along the CSF pathways. Significant progress in research of this tumor and appropriate treatment is associated with determining the various molecular categories of primary medulloblastomas. This analysis includes certain factors of cytogenetic and transcriptional proliferation. Modern treatment approaches for patients older than 3 years include advanced resection, craniospinal irradiation with a boost on the postoperative bed followed by platinum-based chemotherapy. Conventional radiotherapy including craniospinal irradiation results a significant number of complications. Morbidity rate is increased throughout long-term follow-up. Secondary tumors including glioblastomas are under special attention since their occurrence is associated with a fatal outcome. This may partially explaine the fact that chemotherapy without repeated morphological verification doesn't always ensure tumor growth control in patients with recurrent medulloblastomas. The authors consider irradiation-induced glioblastomas secondary to primarily verified medulloblastomas in patients who had previously undergone craniospinal irradiation as a component of combined treatment after tumor resection. It was found that the incidence of this phenomenon is significant and made up about 10% among patients with recurrent medulloblastomas. This value is significantly higher compared to previous data. The authors analyzed patterns of occurrence of irradiation-induced glioblastomas depending on the molecular genetic group and clinical characteristics of patients after primary surgery. Treatment outcomes were estimated too. It was concluded that morphological verification is necessary if long-term recurrence is diagnosed after combined treatment of medulloblastoma.

Tumor pseudoprogression is characterized by temporary tumor enlargement following radiotherapy with subsequent stabilization or regression without additional treatment. This phenomenon has been comprehensively described in patients with malignant gliomas. However, this phenomenon has not been sufficiently studied in patients with low-grade gliomas including pilocytic astrocytomas. In recent years, more and more researches devoted to this problem have appeared in the literature. It seems relevant to conduct a meta-analysis of these data in the modern literature.

Cancer pain is one of the main problem in modern medicine. According European Society for Medical Oncology data, cancer pain prevalence is 64% among patient with terminal stage of disease and in 46% standard pain therapy was ineffective. Radiosurgical hypophysectomy is one of the important and perspective method in cancer pain treatment. This method could be offered patient with chronic disease. According literature review, endocrinology complications were very rare and occurred 10 months after therapy. Value of analgesic effect was 70-90%. In some trials, procedure was effective not only nociceptive, but also in neuropathic pain. More trials require for determination of indications and mechanism of action. The case of successful relief of resistant pain in patient with pancreatic cancer by means of radiosurgical hypophysectomy is described.

Objective: To analyze intracellular pH measurement with phosphorus-31 MR spectroscopy in glioblastoma cells and to compare these data with intracellular pH in healthy volunteers., Material and Methods: There were 10 patients aged 41 - 67 years with supratentorial glioblastomas. Intracellular pH in glioblastoma cells was compared with pH in healthy persons., Results: We found a tendency to increased intracellular pH in glioblastoma cells in comparison with pH in intact brain tissue., Conclusion: Intracellular pH in brain tissue can be used as a potential marker of early abnormalities which could not be detected by conventional MRI. Moreover, these data may be valuable to estimate the efficacy of chemotherapy. The study was supported by Russian Science Foundation (grant No. 18-15-00337).

Post-radiation cyst of the brain is a rare complication that often arises many years after irradiation for head and neck neoplasms. The majority of the articles devoted to this problem are small samples or case reports. Nevertheless, the overall number of these patients is steadily increasing. The feature of post-radiation cysts is gradual enlargement followed by general cerebral and focal symptoms and ineffectiveness of therapy. Some patients with clinically significant post-radiation cysts can require surgical treatment. Insertion of Ommaya reservoir may be preferred in these patients. In some cases, this method is ineffective and more complex surgeries may be required. The objectives of this report were to analyze literature data and describe the patient with multiple recurrent brain cysts after previous irradiation for frontotemporal skin melanoma. Twenty-seven publications were analyzed for the period from 1997 to 2018. According to the literature, the incidence of post-radiation cysts varies from 0.4% to 28%, timing of occurrence - from 2 months to 27 years. These values significantly depend on the underlying disease. We report a 27-year-old patient who admitted to the Burdenko Neurosurgery Center with focal and general cerebral symptoms after irradiation for skin melanoma of the right frontotemporal region. These symptoms were caused by cystic lesion of the right temporal and frontal lobes. Surgical treatment consisted in insertion of 2 Ommaya reservoirs. This approach ensured complete regression of the cyst in the right temporal lobe and mild decrease of the cyst in the right frontal lobe.

Petroclival meningiomas (PCMs) are benign, slowly growing tumors. Surgery still remains the main treatment option for them. The desire for total resection of large extended PCMs often leads to the development or worsening of persistent neurological deficits. This paper presents a review of the world literature devoted to petroclival meningiomas. We discuss the issues of PCM classification, biology, diagnosis, and selection of the optimal algorithm for their treatment.

Objective: To study the effect of metabolic characteristics of the tumor determined by 99mTc-MIBI single-photon emission computed tomography (SPECT) and various molecular genetic features on the outcomes of combination treatment of hemispheric glioblastomas., Material and Methods: This single-center prospective cohort study involved 68 patients aged 25-78 years (38 males and 30 females) with primary glioblastomas. Hypermetylation of the promotor region of the MGMT gene was observed in 24 (42%) out of 57 patients. The IDH1 mutation was revealed in two (3.5%) patients. The catamnestic data were available for 66 out of 68 patients. The first SPECT/CT study was carried out before chemoradiation therapy; the second SPECT/CT study was performed after the chemoradiation therapy. In each study, quantitative measures were calculated for the early (15-30 min after the patient had received a radiopharmaceutical) and late (after 45-60 min) phases., Results: The actuarial survival rates after 12 and 24 months were 69.6 and 29.1%, respectively. The median overall survival rate was 17.5 months (95% CI 12.9-20.3). Favorable prognostic factors for overall survival included the higher uptake index (UI) in the late phase compared to UI in the early phase of the first SPECT/CT study (p=0.0444), dynamics of changes in UI during the second SPECT/CT compared to baseline over 10% (p=0.0436), MGMT hypermethylation (p=0.0003), and duration of the period between surgery and initiation of chemoradiotherapy being <1 month (p=0.0008). No statistically significant correlations were revealed between the absolute UI values in the tumor and its molecular genetic features., Conclusion: The 99m Tc-MIBI SPECT/CT can be used to predict overall survival and to plan radiation therapy of glioblastoma as it is more readily available at primary healthcare facilities than amino acid PET.

In most cases, oncogene amplification are prognostic and predictive markers for various tumors, therefore DNA probes are unable to reveal changes in the copy numbers should not be used to diagnose malignant tumors., Objective: To comparatively analyze DNA probes from different manufacturers to detect MYC gene amplification in routine practice., Material and Methods: The study material was formalin-fixed paraffin-embedded medulloblastoma fragments from 4 patients, with discrepancies in the results in the detection of MYC gene amplification., Results: MYC gene amplification was determined using DNA probes: Kreatech MYC (8q24)/SE 8, Vysis LSI MYC SO, Vysis CEP 8 (D8Z2) SG, and Zytolight SPEC MYC/CEN 8 Dual Color Probe. The use of the probes Kreatech TERC (3q26)/MYC (8q24)/SE7 Triple-Color probe failed to detect MYC gene amplification; this probe showed a balanced profile of chromosome 8., Conclusion: In routine practice, fluorescence in situ hybridization with the DNA probes Kreatech MYC (8q24)/SE 8, Vysis LSI MYC SO, Vysis CEP 8 (D8Z2) SG and Zytolight SPEC MYC/CEN 8 Dual Color Probe can be the method of choice for studying the copy number of the MYC gene. However, the authors strongly recommend that the Kreatech TERC (3q26)/MYC (8q24)/SE7 Triple-Color should not be used for this purpose. In addition, probes for fluorescence in situ hybridization must be necessarily tested in large reference laboratories dealing with one or another area of oncopathology.

Evaluation of brain metabolism is an important part in examination of brain lesions. Phosphorus magnetic resonance spectroscopy opens up great opportunities for studying the energy metabolism and allows noninvasive examination of metabolic processes occurring both in healthy and in pathologic brain tissue by obtaining a spectrum of phosphorus-containing metabolites involved in the turnover of cell membrane phospholipids. The technique presented in this paper was used to conduct 31 P MR spectroscopy and to estimate the ratio between the peaks of the main metabolites and intracellular pH of the healthy brain tissue of 23 volunteers in the age group under 30 years old in clinical settings. Based on the recorded stable phosphorus spectra of metabolites of the healthy brain tissue, the value of intracellular pH (6.963±0.044) and the ratio of the main PME/PDE peaks (1.17±0.20) were calculated. The database was created to subsequently analyze the metabolic changes in brain tissue spectra in norm and in pathology, as well as the intracellular pH variations that have diagnostic and prognostic value.

The article describes the clinical observation of a 41-year-old woman suffering from non-Hodgkin's B-cell primary lymphoma of the central nervous system involving both eyes. The article features the data on 85-month follow-up, as well as description of the clinical and instrumental features of the disease. The study provides analysis of the long-term results of combined treatment of recurrent primary intraocular lymphoma including repeated courses of radiation therapy.