[Astrocytoma with 1p19q codeletion].

Using the example of a recurrent tumor with a 10-year follow-up, the authors show that mutation of the 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.

[Sarcomas of the central nervous systems. Clinical observations].

Here we report three patients with rare primary intracranial sarcomas, two of them were CIC-sarcomas and one was a -sarcoma. Tumors were examined using DNA methylation. It is important to study of CIC fusions and mutations in malignant brain tumors.

[Primary sellar neuroblastoma (clinical case and literature review)].

Neuroblastoma is a malignancy developing from the embryonic neuroblasts of sympathetic nervous system. Primary sellar neuroblastomas are extremely rare (there are currently only 11 case reports in the literature). Possible development of neuroblastoma in sellar region expands differential diagnosis of local processes due to inclusion of neuroblastoma into the spectrum of suspected tumors.

[Heterogeneity of tumor cells in glioblastomas].

Objective: To comprehensively assess the functional molecular biological status of different tumor cell populations in glioblastoma samples.

Material And Methods: The activity of Ki-67, Bcl-2, and BCL6 expression was determined in 20 tumor samples from patients with glioblastoma. After that, a spatial analysis of heterogeneity in the expression of these markers in different tumor cell populations was carried out using computer and software tools and calculating the percentage of cells (PC) expressing this marker (Ki-67 labeling index (LI)) and a modified histoscore in different cell clusters.

[Central nervous system atypical teratoid/rhabdoid tumor without loss of nuclear expression of INI1].

The paper describes a clinical case of atypical teratoid/rhabdoid tumor with preserved INI1 expression and SMARCA4 gene mutations in an 8-month-old girl. Genome-wide DNA methylation, hierarchical clustering, and next-generation sequencing were used to make a tumor diagnosis. However, BRG1 immunohistochemical examination may be recommended in the routine practice of diagnosis and study of childhood CNS malignant tumors.