Akkus Zeynettin, Ali Issa, Sedlář Jiří, Agrawal Jay P, Parney Ian F, Giannini Caterina, Erickson Bradley J
Radiology Informatics Laboratory, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA.
J Digit Imaging. 2017 Aug;30(4):469-476. doi: 10.1007/s10278-017-9984-3.
Several studies have linked codeletion of chromosome arms 1p/19q in low-grade gliomas (LGG) with positive response to treatment and longer progression-free survival. Hence, predicting 1p/19q status is crucial for effective treatment planning of LGG. In this study, we predict the 1p/19q status from MR images using convolutional neural networks (CNN), which could be a non-invasive alternative to surgical biopsy and histopathological analysis. Our method consists of three main steps: image registration, tumor segmentation, and classification of 1p/19q status using CNN. We included a total of 159 LGG with 3 image slices each who had biopsy-proven 1p/19q status (57 non-deleted and 102 codeleted) and preoperative postcontrast-T1 (T1C) and T2 images. We divided our data into training, validation, and test sets. The training data was balanced for equal class probability and was then augmented with iterations of random translational shift, rotation, and horizontal and vertical flips to increase the size of the training set. We shuffled and augmented the training data to counter overfitting in each epoch. Finally, we evaluated several configurations of a multi-scale CNN architecture until training and validation accuracies became consistent. The results of the best performing configuration on the unseen test set were 93.3% (sensitivity), 82.22% (specificity), and 87.7% (accuracy). Multi-scale CNN with their self-learning capability provides promising results for predicting 1p/19q status non-invasively based on T1C and T2 images. Predicting 1p/19q status non-invasively from MR images would allow selecting effective treatment strategies for LGG patients without the need for surgical biopsy.
多项研究表明,低级别胶质瘤(LGG)中1号染色体短臂/19号染色体长臂(1p/19q)的共缺失与治疗的积极反应及更长的无进展生存期相关。因此,预测1p/19q状态对于LGG的有效治疗规划至关重要。在本研究中,我们使用卷积神经网络(CNN)从磁共振图像(MR)中预测1p/19q状态,这可能是手术活检和组织病理学分析的一种非侵入性替代方法。我们的方法包括三个主要步骤:图像配准、肿瘤分割以及使用CNN对1p/19q状态进行分类。我们纳入了总共159例LGG患者,每人有3个图像切片,其1p/19q状态经活检证实(57例未缺失,102例共缺失),并提供了术前增强T1加权像(T1C)和T2加权像。我们将数据分为训练集、验证集和测试集。对训练数据进行平衡处理,使类别概率相等,然后通过随机平移、旋转以及水平和垂直翻转的迭代进行扩充,以增加训练集的大小。我们在每个epoch中对训练数据进行洗牌和扩充,以对抗过拟合。最后,我们评估了多尺度CNN架构的几种配置,直到训练和验证准确率趋于一致。在未见测试集上表现最佳的配置结果为:灵敏度93.3%、特异性82.22%、准确率87.7%。具有自学习能力的多尺度CNN在基于T1C和T2图像非侵入性预测1p/19q状态方面提供了有前景的结果。从MR图像非侵入性预测1p/19q状态将允许为LGG患者选择有效的治疗策略,而无需进行手术活检。