Use of magnetic resonance imaging features as radiomic markers in pre-operative evaluation of extra-axial tumor grade

Abstract

Backgraund: Extra-axial tumors are one of the tumor groups which are difficult for primary differential diagnostics. Detection and standardization of radiomic markers is one of the main problems of our time.
 Aim: To detect radiomic markers for preoperative assessment of extra-axial tumor grade.
 Materials and methods: Retrospective analysis of MRI (1.5T) data of 156 patients with extra-axial tumors. The patients were divided into 2 groups: Group 1(n=106) with perifocal changes, Group 2 (n=50) extra-axial tumor without perifocal changes. Diffusion and perfusion sequences were included in the scanning protocol. The areas of interest were (1) the lesion and (2) the area of perifocal changes. Measurements were made from the lesion and the area of perifocal changes on ACD and DSE maps, DCE was analyzed.
 Results: The maximum lesion size in Group 1 was 2.2cm (1.4; 4.3), in Group 2 - 1.2cm (0.9; 3.5). In Group 1 diffusion restriction from the lesion was detected in 42 patients (39.6%), in Group 2 in 7 patients (14%). The maximum size of perifocal changes in Group 1 was 2.85cm (1.5; 4.7). Diffusion restriction was detected in 52 cases (49.1%). In patients of Group 2 with verified meningioma multivariate linear regression analysis showed that the maximum size of the lesion demonstrated a 3.3-time increase of rCBF from the area of perifocal changes (coef. 3.3 CI 1.27; 5.28) p = 0.003, however, it demonstrated a 4-time decrease of rCBF (coef. 4 CI -7.46;-0.71) p = 0.02.
 Conclusions: Perfusion and diffusion method combined with anatomical sequences show potential and can be used as radiomic markers for diagnostic assessment and treatment of extra-axial tumors. There is further potential in detecting radiomic functional markers from the area of perifocal changes.