Gryazov A. Radiosurgical and radiation diagnostic technology in the treatment and follow-up of patients with brain metastatic lesions

Dissertation is devoted to solving actual scientific problem of increasing the effectiveness of treatment patients with brain metastatic lesions by optimizing radiosurgical intervention protocols and the development of an algorithm to assess their effectiveness with the use of high information technologies of magnetic resonance and multidetector computed tomography. The results of radiosurgical treatment of 260 patients with a diagnosis of cancer metastasis to the brain (663 metastatic lesions) who underwent stereotactic radiosurgery by LINAC "Trilogy" ( "Varian", USA), including 150 patients undergoing radiosurgery using radiosensitizers and 110 patients - control group. During the radiosurgical treatment of brain metastases was suggested the use of radiosensitizers, with significantly improving the results of treatment - an increase of progression-free survival of patients to 16.2 months (compared to 8 months) and overall survival to 18 months (compared to 9 months) (p = 0.0000). We have improved assessment of volumetry indicators in the differential diagnosis of tumor recurrence and post-radiation changes - accuracy reached with validity <0.001 - 80.0%, measurement of diffusion coefficient - 93.8 %, measurement of cerebral blood flow, according to an arterial spin labeling - 96,9% - 98.4%. It is proved that the predictors of success of radiosurgical treatment of brain metastases are: the use of radiosensitization (hazard ratio 3.11, p = 0.0000), an early response to treatment (a significant reduction in the volume and the coefficient of variation in tumor size, p = 0.0000) increase in measurement of diffusion coefficient ADC a week after the SRS (p = 0.0000), decrease in the cerebral blood flow and cerebral blood volume and increase of mean transfer time according to MDCT and MRI perfusion ranging from 3-6 weeks after SRS (p = 0.0000).