Table 3.
Comparison between IDHwt grade II (n = 29) and IDHwt grade III (n = 166) gliomas meeting cIMPACT-NOW criteria for “Diffuse astrocytic glioma, IDH-wildtype, with molecular features of glioblastoma (grade IV)” (molecular GBM)
| IDHwt Grade II and III Gliomas Meeting the definition of molecular GBM (n = 195) | IDHwt Grade II Gliomas Meeting the Definition of Molecular GBM (n = 29) | IDHwt Grade III Gliomas Meeting the Definition of Molecular GBM (n = 166) | P-value* | |
|---|---|---|---|---|
| Age, y, median (range) | 58.7 (20.8–83.0) | 58.6 (20.8–82.1) | 58.8 (22.2–83.0) | 0.86 |
| Male | 124/195 (64%) | 24/29 (83%) | 100/166 (60%) | 0.022 |
| Preoperative KPS, median (range) | 90 (60–100) | 90 (70–100) | 80 (60–100) | 0.026 |
| Extent of resection | ||||
| Biopsy | 99/177 (56%) | 19/28 (68%) | 80/149 (54%) | 0.33 |
| Partial resection | 31/177 (18%) | 5/28 (18%) | 26/149 (17%) | |
| Gross total resection | 47/177 (27%) | 4/28 (14%) | 43/149 (29%) | |
| Treatment | ||||
| Chemotherapy alone | 41/169 (24%) | 10/25 (40%) | 30/144 (21%) | <0.0001 |
| Concomitant or sequential RT-CHT | 98/169 (58%) | 12/25 (48%) | 87/144 (60%) | |
| Radiotherapy alone | 27/169 (16%) | 0/25 (0%) | 27/144 (19%) | |
| Surveillance | 3/169 (2%) | 3/25 (12%) | 0/144 (0%) | |
| Molecular profile | ||||
| TERT promoter mutation | 171/187 (91%) | 23/28 (82%) | 148/159 (93%) | 0.12 |
| EGFR amplification | 77/180 (43%) | 4/26 (15%) | 73/155 (47%) | 0.0037 |
| 7+ | 96/141 (68%) | 10/26 (38%) | 86/116 (74%) | 0.00089 |
| 10- | 114/170 (67%) | 10/26 (36%) | 105/145 (72%) | 0.00045 |
| 7+/−10 | 83/151 (55%) | 7/26 (27%) | 76/126 (60%) | 0.00194 |
| 9p loss | 47/170 (28%) | 3/26 (12%) | 44/145 (30%) | 0.057 |
| CDKN2A deletion | 57/180 (32%) | 3/26 (12%) | 54/155 (35%) | 0.023 |
| Number of c-IMPACT criteria met | ||||
| One | 52/154 (34%) | 20/26 (77%) | 33/129 (26%) | <0.0001 |
| Two or 3 | 102/154 (66%) | 6/26 (23%) | 96/129 (74%) | |
| Reason for meeting c-IMPACT criteria: | ||||
| TERT promoter mutation without EGFR amplification or +7/−10 | 43/156 (28%) | 16/26 (62%) | 28/131 (21%) | <0.0001 |
| EGFR amplification and/ or +7/−10 without TERT promoter mutation | 15/156 (10%) | 5/26 (19%) | 10/131 (8%) | |
| TERT promoter mutation plus EGFR amplification and/or +7/−10 | 98/156 (63%) | 5/26 (19%) | 93/131 (71%) | |
| Median OS, mo | 19.2 | 42.2 | 17.2 | <0.0001 |
RT-CHT = radiochemotherapy; +7 = whole chromosome 7 gain; −10 = whole chromosome 10 loss. *P values refer to the comparison between the 2 subgroups identified by initial WHO grade; in bold statistically significant results.