Schnurman Zane, Nakamura Aya, McQuinn Michelle W, Golfinos John G, Roland J Thomas, Kondziolka Douglas
Departments of1Neurosurgery and.
2Otolaryngology-Head and Neck Surgery, NYU Langone Health, New York, New York.
J Neurosurg. 2019 Aug 2;133(3):742-748. doi: 10.3171/2019.5.JNS1923. Print 2020 Sep 1.
There remains a large discrepancy among surgeons in expectations of vestibular schwannoma (VS) growth. The anticipated growth rate of a VS and its potential clinical impact are important factors when deciding whether to observe the lesion over time or to intervene. Previous studies of VS natural growth remain limited, mostly confined to linear measurements, often without high-resolution, thin-sequence imaging. The present study comprehensively assessed natural tumor growth rates using volumetric measurements.
Between 2012 and 2018, 212 treatment-naïve patients diagnosed with a unilateral VS were evaluated. A total of 699 MR images were assessed, with a range of 2-11 MR images per patient. All MR images preceded any intervention, with patients subsequently being observed through completion of data analysis (36%) or treated with stereotactic radiosurgery (32%) or microsurgical resection (32%). To determine precise tumor volumes, the tumor area was outlined on every slice, and the products of the area and slice thickness were summed (99% of scans were ≤ 1-mm slice thickness). A multilevel model with random effects was used to assess the mean volume change over time. Each tumor was categorized as one of the following: growing (volume increase by more than 20% per year), fast growing (volume increase by more than 100% per year), stable (volume change between 20% decrease and 20% increase per year), and shrinking (volume decrease by more than 20% per year).
The mean VS volumetric growth rate was 33.5% per year (95% CI 26.9%-40.5%, p < 0.001). When assessing the frequencies of individual tumor annual growth rates, 66% demonstrated growth (30% fast growing), 33% were stable, and 1% exhibited shrinking over an average interval of 25 months. Larger tumors were associated with increased absolute growth, but there was no relationship between tumor size and proportional growth rate. There was also no relationship between patient age and tumor growth rate.
This study comprehensively assessed VS volumetric growth rates using high-resolution images and was conducted in a large and diverse patient sample. The majority of the tumors exhibited growth, with about one-third growing at a rate of 100% per year. These findings may contribute to a consensus understanding of tumor behavior and inform clinical decisions regarding whether to intervene or observe.
外科医生对前庭神经鞘瘤（VS）生长的预期存在很大差异。VS的预期生长速率及其潜在的临床影响是决定是长期观察病变还是进行干预的重要因素。以往关于VS自然生长的研究仍然有限，大多局限于线性测量，且常常缺乏高分辨率、薄层序列成像。本研究使用体积测量全面评估了肿瘤的自然生长速率。
在2012年至2018年期间，对212例未经治疗的单侧VS患者进行了评估。共评估了699张磁共振成像（MR）图像，每位患者的图像数量在2至11张之间。所有MR图像均在任何干预之前获取，随后患者通过数据分析完成（36%）或接受立体定向放射外科治疗（32%）或显微手术切除（32%）进行观察。为确定精确的肿瘤体积，在每一层图像上勾勒出肿瘤区域，并将区域与层厚的乘积相加（99%的扫描层厚≤1毫米）。使用具有随机效应的多级模型评估随时间的平均体积变化。每个肿瘤被分类为以下之一：生长型（每年体积增加超过20%）、快速生长型（每年体积增加超过100%）、稳定型（每年体积变化在减少20%至增加20%之间）和缩小型（每年体积减少超过20%）。
VS的平均体积生长速率为每年33.5%（95%置信区间26.9%-40.5%，p<0.001）。在评估单个肿瘤的年生长速率频率时，66%的肿瘤表现为生长（30%为快速生长），33%为稳定型，1%在平均25个月的间隔内表现为缩小。较大的肿瘤与绝对生长增加相关，但肿瘤大小与比例生长速率之间没有关系。患者年龄与肿瘤生长速率之间也没有关系。
本研究使用高分辨率图像全面评估了VS的体积生长速率，并且是在一个大型且多样化的患者样本中进行的。大多数肿瘤表现为生长，约三分之一的肿瘤以每年100%的速率生长。这些发现可能有助于就肿瘤行为达成共识理解，并为关于是否进行干预或观察的临床决策提供依据。
