背景:具有IDH1/2突变而无1p19q共缺失的胶质瘤已被鉴定为IDH突变型星形细胞瘤(IDHmut星形细胞瘤)的独特诊断实体。细胞周期蛋白依赖性激酶4抑制剂A/B(CDKN2A/B)的纯合缺失最近已被纳入这些肿瘤的分级中。组织学参数是否仍然有助于分子分类之上的预后信息的问题,仍然没有答案。在这里,我们评估了一致的组织学参数,以提供IDHmut星形细胞瘤的额外预后价值。
方法:一个由7名神经病理学家组成的国际小组在EORTC试验22033-26033(低级别神经胶质瘤)的192个IDHmut星形细胞瘤和EORTC26053(CATNON)的263个(1p19q非共缺失间变性神经胶质瘤)的虚拟显微镜图像中对13个明确的组织学特征进行了评分。对于192个神经胶质瘤,CDKN2A/B状态是已知的。共识(协议≥4/7小组成员)的组织学特征与CDKN2A/B的纯合缺失(HD)一起测试了独立的预后能力。
结果:在一致的组织学参数中,有丝分裂计数(每10个高功率场的2个有丝分裂的截止值,标准化为0.55mm的场直径和0.24mm2的面积)显着影响PFS(p=0.0098),并略微影响OS(p=0.07)。有丝分裂计数也显著影响HDCDKN2A/B肿瘤的PFS,但不是操作系统,可能是由于随访数据有限。
结论:有丝分裂指数(每1040倍HPF截止值2)在没有HDCDKN2A/B的IDHmut星形细胞瘤中具有预后意义。因此,有丝分裂指数可能指导具有天然CDKN2A/B状态的IDHmut星形细胞瘤患者的治疗方法.
Gliomas with IDH1/2 mutations without 1p19q codeletion have been identified as the distinct diagnostic entity of IDH mutant astrocytoma (IDHmut astrocytoma). Homozygous deletion of Cyclin-dependent kinase 4 inhibitor A/B (CDKN2A/B) has recently been incorporated in the grading of these tumors. The question of whether histologic parameters still contribute to prognostic information on top of the molecular classification, remains unanswered. Here we evaluated
consensus histologic parameters for providing additional prognostic value in IDHmut astrocytomas.
An international panel of seven neuropathologists scored 13 well-defined histologic features in virtual microscopy images of 192 IDHmut astrocytomas from EORTC trial 22033-26033 (low-grade gliomas) and 263 from EORTC 26053 (CATNON) (1p19q non-codeleted anaplastic glioma). For 192 gliomas the CDKN2A/B status was known.
Consensus (agreement ≥ 4/7 panelists) histologic features were tested together with homozygous deletion (HD) of CDKN2A/B for independent prognostic power.
Among
consensus histologic parameters, the mitotic count (cut-off of 2 mitoses per 10 high power fields standardized to a field diameter of 0.55 mm and an area of 0.24 mm2) significantly influences PFS (P = .0098) and marginally the OS (P = .07). Mitotic count also significantly affects the PFS of tumors with HD CDKN2A/B, but not the OS, possibly due to limited follow-up data.
The mitotic index (cut-off 2 per 10 40× HPF) is of prognostic significance in IDHmut astrocytomas without HD CDKN2A/B. Therefore, the mitotic index may direct the therapeutic approach for patients with IDHmut astrocytomas with native CDKN2A/B status.