Different risk factors for multiple and unifocal gliomas: a comparative study of radiological, pathological and clinical characteristics

Abstract

Background: This retrospective study compared two types of gliomas and two subtypes of multiple gliomas.

Methods: The clinical manifestations, magnetic resonance imaging (MRI) findings, pathological characteristics, and clinical outcomes of 188 patients with unifocal and 94 patients with multiple gliomas (59 with multifocal and 35 with multicentric gliomas) were analyzed.

Results: Compared with patients with unifocal glioma, those with multiple gliomas were older (P=0.001) and more likely to be male (χ² = 4.857, P=0.028). Patients with multiple gliomas had smaller extent of surgical resection (χ² = 161.016, P<0.001) and a worse prognosis (χ² = 43.733, P<0.001) than those with unifocal gliomas. Multiple gliomas were more likely to have a non-superficial location (χ² = 51.758, P<0.001), obvious peritumoral oedema (χ² = 9.688, P=0.008), intense enhancement (χ² = 24.547, P<0.001), a higher WHO grade (P=0.001), a lower ratio of isocitrate dehydrogenase (IDH) mutation (χ² = 51.770, P<0.001), and codeletion of 1p19q (χ² = 8.637, P=0.003). Tumor location and IDH status were identified as independent risk factors for multiple gliomas (P<0.001 and P=0.003, respectively). Deep tumor location was found to be the only factor related to unfavorable overall survival (OS) in multiple gliomas. Patients with multifocal gliomas were more likely to be male than patients with multicentric gliomas (χ² = 6.521, P=0.011). The locations of multifocal and multicentric gliomas were significantly different (P=0.048). WHO grade was identified as an independent prognostic factor (P=0.034) in patients with multicentric gliomas but not in those with multifocal gliomas.

Conclusions: The demographic characteristics, extent of resection, radiological features, pathological features and prognostic factors differ between patients with multiple gliomas and those with unifocal gliomas. The clinical and radiological features differ between patients with different subtypes of multiple gliomas. Multiple gliomas located only in superficial regions are more likely to be multicentric gliomas and the prognosis is solely related to the WHO grades, providing valuable guidance for clinical treatment.

Keywords: diagnosis; differentiation; multicentric gliomas; multifocal gliomas; prognosis.

Figure 1

Typical manifestations of multifocal and multicentric gliomas (A), Multifocal gliomas type 1: Two separate lesions communicate through white matter fibers, appearing as hyperintense signal on an axial fluid-attenuated inversion recovery (FLAIR) image (arrow). (B, C), Multifocal gliomas type 2: Separate lesions abutting the ventricular system are shown on an axial FLAIR image and post-contrast T1-weighted image. (D), Multifocal gliomas type 3: Satellite foci adjacent to the main tumor are shown on a sagittal post-contrast T1-weighted image. (E) Multicentric gliomas: Isolated lesions in different hemispheres are shown on an axial FLAIR image.

Figure 2

Kaplan-Meier curves comparing OS and PFS between patients with unifocal/multiple gliomas and patients with multifocal/multicentric gliomas (A), Kaplan-Meier curves comparing the overall survival (OS) and progression-free survival (PFS) of the unifocal and multiple gliomas groups are shown. (B), Kaplan-Meier curves comparing the OS and PFS of the multifocal and multicentric gliomas groups are shown.

Figure 3

Penalized cox model of unifocal glioma group The C-index is 0.882. Patient age, deep tumor location, World Health Organization grade 4, marked enhancement intensity, IDH (mutation/wild type), and TERT promoter mutation status (positive/negative) are independent risk factors for overall survival in the unifocal glioma group.