Article Figures & Data
Figures
- Fig 1.
Examples of MR imaging features in glioblastoma. A, Tumor classified with a regular (left) or irregular margin (right). B, Tumor classified with a fungating (left) or nonfungating margin (right). C, Tumors classified with a cystic component (left) or noncystic component (right). D, Tumor classified with (left) and without (right) radiologic necrosis. E, Tumor classified with low (limited, left) and high (extensive, right) PTE. F, Tumor classified as being multifocal. G, tumor classified with hemorrhage. Gd indicated gadolinium; C, contrast.
- Fig 2.
The 3 telomere maintenance mechanism subtypes are associated with differences in patient survival. Eighty cases were those used in a previous study,4 and 100 cases were new to this study.
Tables
Imaging Feature with: Classification Criteria Regular enhancing margin Yes Smooth enhancing margin on post-Gd T1 No Lack of smooth enhancing margin on post-Gd T1 Fungating margin Yes Thick heterogeneous brushlike enhancing rim on post Gd T1 No Lack of thick heterogeneous brushlike enhacing rim on post-Gd T1 Cystic Yes A well-circumscribed region with low T1 and high T2 signal; loses signal on the FLAIR sequence No Lack of well-circumscribed region with low T1 and high T2 signal; does not lose signal on the FLAIR sequence Proportion of necrosis Yes An area within the tumor that had high signal on T2 and low signal on T1; had heterogeneous enhancement on post-Gd T1; the proportion of the tumor estimated to represent more than 5% necrosis No Less than 5% or none Proportion of edemaa Limited (<50% of the entire abnormality) Less than half of the entire abnormality is estimated to represent vasogenic edema Extensive (> 50% of the entire abnormality) More than half of the entire abnormality is estimated to represent vasogenic edema Multifocal and multicentric lesion Yes Two or more enhancing intra-axial tumors on post-Gd T1 No One intra-axial tumor on post-Gd T1 Hemorrhage Yes Tumor has an area of internal high or isolated T1 and low T2; area of internal high T1 and high T2; area of internal low T1 and low T2. Takes into account that the signal characteristics differ depending on the age of the hemorrhage. SWI sequences were also used. No No hemorrhage Note:—Gd indicates gadolinium.
↵a The protocol for measuring PTE grade was based on that by Wu et al5 and Hartmann et al.22
MRI Feature % Where All 3 Reviewers Agree κ Value Regular margin 62.9% 0.23 Fungating margin 64.6% 0.28 Cystic 86.2% 0.71 Necrosis 72.6% 0.50 Limited PTE 70.7% 0.43 Hemorrhage 78.3% 0.56 Multifocal lesion 85.6% 0.71 Demographics Telomere Maintenance Subtype Pearson χ2 (or F-Ratio) and P Valuesa ALT+/M− (n = 26) ALT−/M− (n = 92) ALT−/M+ (n = 56) % Male (no.) 57.7 (15) 63 (58) 57.1 (32) 0.6, .742 Mean age (range), yrs 45.9 (16–66) 64.1 (40–81) 63.2 (39–82) 34.8, <.001 Median survival, mo 21.0 10.6 7.1 40.1, <.001 % Treated with at least 4 cycles of temozolomide (no.) 42.3 (11) 38 (35) 32 (18) 0.63, .629 % Treated with radiotherapy (no.) 84.6 (22) 78.3 (72) 92.9 (52) 5.5, .064 Type of surgery Biopsy, % (no.) 15.4 (4) 24 (22) 16 (9) 37.9, <.0001 Near total, % (no.) 76.9 (20) 61 (56) 27.3 (15) Partial 8 (2) 15.2 (14) 56.4 (31) MGMT promoter methylation status, % (no.) 61.5 (16) 45 (36) 48 (25) NS IDH1 and IDH2 mutation status, % (no.) 73 (19) 9 (8) 5 (3) 67, <.0001 Note:—NS indicates not significant.
↵a Statistical comparisons were made between 3 groups: ALT+/M−, ALT−/M−, and ALT−/M+.
MRI Feature Telomere Maintenance Subtype ALT+/M− ALT−/M− ALT−/M+ Pearson χ2 and P Valuesa ALT+/M+ No. of patients 26 92 56 6 Regular margin, % (no.) 58 (15) 30 (28) 30 (17) 7.3, .026 33 (2) Fungating margin, % (no.) 19 (5) 53 (49) 61 (34) 12.8, .002 67 (4) Cystic component, % (no.) 39 (10) 24 (22) 11 (6) 8.5, .014 50 (3) Radiologic necrosis, % (no.) 58 (15) 73 (67) 86 (48) 7.7, .021 83 (5) Extensive PTE, % (no.) 23 (6) 23 (21) 45 (25) 8.6, .014 17 (1) Multifocal lesion, % (no.) 15 (4) 12 (11) 23 (13) NS 33 (2) Hemorrhage, % (no.) 8 (2) 20 (18) 7 (4) NS 3 (2) Note:—NS indicates not significant.
↵a Statistical comparisons were made between 3 groups: ALT+/M−, ALT−/M−, and ALT−/M+.
MRI Feature Tumor Type IDH1 and IDH2 Mutant (n = 30) IDH1 and IDH2 Wild-Type (n = 150) Pearson χ2 and P Values Regular margin 50% 31% NS Fungating margin 33% 55% 4.8 .028 Cystic component 37% 17% 5.7 .017 Radiologic necrosis 63% 77% NS Extensive PTE 23% 32% NS Multifocal lesion 10% 16% NS Hemorrhage 10% 15% NS Note:—NS indicates not significant.
- Table 6:
Cox regression analysis to test if radiology features added to telomere maintenance subtype and MGMT promoter methylation status in predicting patient survival
Category Variable Wald Value df Significance P Molecular subtype 26 2 <.0001 MGMT 6.89 1 .009 Cystic 4 1 .045
