Division of Neurosurgery, Department of Surgery, Duke university Medical Center, North Carolina 27710, USA.
Neurosurg Focus. 2013 Feb;34(2):E7. doi: 10.3171/2012.12.FOCUS12343.
Low-grade gliomas (LGGs) are indolent tumors that have the potential to dedifferentiate into malignant high-grade tumors. Recent studies have demonstrated that cerebellar low-grade tumors have a better prognosis than supratentorial tumors, although no study has focused on the risk factors for poor prognosis in cerebellar LGGs in adults. The authors of the current study aimed to address both of these concerns by using a large cohort derived from a national cancer registry and a smaller cohort derived from their institution's experience.
Adults with diagnosed Grade I and Grade II gliomas of the cerebellum were identified in the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate Cox proportional hazard models were used to predict rates of survival, and the log-rank test was applied to evaluate differences in Kaplan-Meier survival curves. An institutional cohort was created by isolating all patients whose surgical pathology revealed an LGG of the cerebellum. Excluded from analysis were patients in whom a glioma was first diagnosed under the age of 18 years and those whose tumors could not be definitively determined to arise from the cerebellum. Results Data from the local cohort (11 patients) demonstrated that the most common presenting symptom was headache, which occurred in more than 70% of the cohort. Approximately half of the patients in this cohort had symptomatic improvement after treatment.
from the SEER cohort (166 patients) revealed that adults with Grade I gliomas were slightly younger than those with Grade II tumors (p < 0.01), but no other demographic differences were observed. Patients with Grade I tumors were twice as likely to undergo gross-total resection (54% vs 21%), and those with Grade II gliomas were much more likely to receive postoperative radiation (3% vs 48%). Five-year survival was greater in the patients with Grade I gliomas than in those with Grade II lesions (91% vs 70%). Multivariate analysis revealed that an age ≥ 40 years (HR 7.30, 95% CI 3.55-15.0, p < 0.0001) and Grade II tumors (HR 2.76, 95% CI 1.12-6.84, p = 0.028) were risk factors for death, whereas female sex was protective (HR 0.28, 95% CI 0.14-0.59, p < 0.001). Log-rank tests revealed that a cerebellar location was protective (p < 0.0001), but this relationship was only true for Grade II tumors (p < 0.0001). Survival in patients with Grade I gliomas was not different based on the various lesion locations (p = 0.21).
Taken together, adults with cerebellar WHO Grade I and II astrocytomas have a much more favorable survival curve than those with similar supratentorial tumors. Research demonstrates that the primary driver of this phenomenon is the improved survival in patients with cerebellar Grade II gliomas.
低级别胶质瘤（LGG）是一种潜在的惰性肿瘤，有向恶性高级别肿瘤分化的可能。最近的研究表明，小脑低级别肿瘤的预后优于幕上肿瘤，尽管尚无研究关注成人小脑 LGG 预后不良的危险因素。作者通过使用来自国家癌症登记处的大型队列和来自机构经验的较小队列来解决这两个问题。
在监测、流行病学和最终结果（SEER）数据库中确定诊断为小脑 I 级和 II 级胶质瘤的成年人。使用多变量 Cox 比例风险模型预测生存率，并应用对数秩检验评估 Kaplan-Meier 生存曲线的差异。通过分离所有手术病理显示小脑 LGG 的患者来创建机构队列。分析排除了首次诊断年龄在 18 岁以下的患者和那些不能明确确定肿瘤源自小脑的患者。
来自本地队列（11 例）的数据表明，最常见的首发症状是头痛，超过 70%的患者有此症状。该队列约一半的患者在治疗后症状有所改善。
来自 SEER 队列（166 例）的结果表明，I 级胶质瘤患者比 II 级肿瘤患者略年轻（p<0.01），但未观察到其他人口统计学差异。I 级肿瘤患者行大体全切除的可能性是 II 级肿瘤患者的两倍（54%比 21%），而 II 级胶质瘤患者更有可能接受术后放疗（3%比 48%）。I 级胶质瘤患者的 5 年生存率高于 II 级病变患者（91%比 70%）。多变量分析显示，年龄≥40 岁（HR7.30，95%CI3.55-15.0，p<0.0001）和 II 级肿瘤（HR2.76，95%CI1.12-6.84，p=0.028）是死亡的危险因素，而女性是保护因素（HR0.28，95%CI0.14-0.59，p<0.001）。对数秩检验显示小脑位置具有保护作用（p<0.0001），但这种关系仅适用于 II 级肿瘤（p<0.0001）。I 级胶质瘤患者的生存与各种病变位置无关（p=0.21）。
综上所述，与具有相似幕上肿瘤的患者相比，成人小脑 WHO I 级和 II 级星形细胞瘤的生存曲线要好得多。研究表明，这种现象的主要驱动因素是小脑 II 级胶质瘤患者生存率的提高。
