Endothelium changes of peritumoral zone capillaries after brain glioblastoma adjuvant radiation therapy

Introduction. Despite the treatment methods’ improvement, the brain glioblastoma(GB) patient survival remains at the level of 12–14 months. In this regard, it is veryrelevant to optimize the choice of the treat-ment of recurrent GB, including usingstereotactic radiosurgery (SRS). Materials and methods. Comparative analysis of theendothelial cells in the capillaries of blood vessels of the brain peritumoral zone (PZ)before (1 group – 32 capillaries) and 12 – 14 months after (2 group – 75 capillaries)adjuvant external radiation therapy (AERT) was performed using transmission electronmicros-copy (TEM). Results. Apoptosis of endotheliocytes was observed in the capillariesof the brain PZ from 2 group much more often than from 1 group (60% and 12.6% ofcapillaries, respectively, p<0.001). Capillary death and thrombosis occurred in 4%and 1.4% of 2 group capillaries. An important finding was that only 69.3 of capillariesfrom 2 group revealed thickening of the basement membrane (BM), and 26.9% of them alsorevealed its peak deformation. Conclusion. 12–14 months after AERT, the brain PZ remainsischemic due to apoptosis of the capillary endothelium, thickening and peak deformationof the BM. The detected signs of revascularization of the brain PZ after previouslyperformed AERT suggest that it is possible to consider SRS as a method of treat-ment forrecurrent brain GB. Keywords: brain glioblastoma, peritumoral zone, endotheliocyteapoptosis, thickening of the basement membrane, stereotactic radiosurgery, glioblastomarelapse