Year: 2025
Type: article
Study design: Observational Study
Abstract: Objective: The perifocal edema zone of glial tumors is an active morphofunctional compartment that determines the volume of vasogenic and cytotoxic edema, clinical symptoms, and resectability.Its morphology remains insufficiently standardized due to heterogeneous sample selection criteria and the lack of uniform semiquantitative scales for assessing the perifocal zone, a fact emphasized by recent reviews on the "non-enhancing" peritumoral area (NEPA) /PFZ.The aim of this study was to characterize the cellular and tissue organization of the perifocal zone (PFZ) and identify tumor cell migration into the edema zone.Methods: A single-center observational morphological study was conducted on 70 consecutive patients aged 25-65 years who underwent surgery for diffuse glial tumors (15 astrocytomas, 15 oligodendrogliomas, 10 anaplastic astrocytomas, 10 anaplastic oligodendrogliomas, and 20 glioblastomas).Primary diffuse gliomas with an accessible PFZ fragment and a complete MRI set were included.PFZ specimens were obtained along the macroscopically determined tumor border during standard resections.Stereological morphometry (microvessel density, perivascular space area, edema index) and selective electron microscopy were performed.The volume of the cerebral cortex was determined using semi-automated T2/FLAIR-MRI segmentation with a gradation of ≤30; 30-60; 60-100; ≥100 cm³; when available, rCBV/ADC and the DTI-ALPS index were also analyzed as a proxy for glymphatic function.Statistical analysis included the t-test/Mann-Whitney test, ANOVA/Kruskal-Wallis test, χ²/Fisher's exact test, Spearman/Pearson correlation.Results: Perifocal edema in all morphological variants of gliomas was characterized by pericellular and perivascular edema, neuroglial loosening, and focal demyelination.The semiquantitative index of edema was the highest in glioblastoma (2.9 (0.2)) points) compared with astrocytoma (2.3 (0.2)) and oligodendroglioma (2.2 (0.2)), (p<0.01).Tumor cell invasion into the PFZ was absent in Grade II astrocytomas and oligodendrogliomas (0 points), was recorded in approximately half of the cases of anaplastic astrocytomas and oligodendrogliomas (1.5 (0.1) and 1.4 (0.1) points)) and was most pronounced in glioblastomas (2.9 (0.1)) points, (p<0.01).Vascular reaction, microgliosis, and lymphocytic-leukocytic infiltration showed a similar gradient with maximum values in glioblastoma (all ≥2.7 (0.1)) points, (p<0.05).The total score of morphological changes in the PFZ was 7.8 (0.6) in low-grade gliomas, 11.4-11.5 (0.9) in anaplastic tumors, and 16.8 (0.7) in glioblastoma (p<0.01 vs Grade II; p<0.05 vs anaplastic forms) and positively correlated with a PFZ volume ≥60 cm³ and less favorable functional outcomes (p<0.05).Based on the morphological profile, angiogenic, inflammatory-reactive, and mixed morphotypes of the PFZ were distinguished; The mixed type was more often associated with a PFO volume ≥60 cm³ and worse early outcomes (mRS/KPS at discharge).Conclusion: The perifocal zone (PFZ) of gliomas is an active morphofunctional compartment with a gradient of tumor cell invasion, vascular remodeling, glial reactivity, and immune infiltration from low-grade gliomas to glioblastoma.Semiquantitative assessment of microvascular density, perivascular space area, and invasion severity in the PFZ can serve as the basis for partially standardizing the morphological description of the perifocal zone and stratifying resectability, residual tumor volume, and recurrence risk.
Author: Zhenishbek M. Karimov
Language: English
Subfield: Genetics
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $350
OpenAlex ID: W7124462305