Department of Computer Science and Engineering, Maharaja Agrasen Institute of Technology, Delhi, India.
Department of Computer Science, Sushant University, India.
Biomed Res Int. 2022 Jul 4;2022:1012684. doi: 10.1155/2022/1012684. eCollection 2022.
Microsatellites are small, repetitive sequences found all across the human genome. Microsatellite instability is the phenomenon of variations in the length of microsatellites induced by the insertion or deletion of repeat units in tumor tissue (MSI). MSI-type stomach malignancy has distinct genetic phenotypes and clinic pathological characteristics, and the stability of microsatellites influences whether or not patients with gastric mesothelioma react to immunotherapy. As a result, determining MSI status prior to surgery is critical for developing treatment options for individuals with gastric cancer. Traditional MSI detection approaches need immunological histochemistry and genetic analysis, which adds to the expense and makes it difficult to apply to every patient in clinical practice. In this study, to predict the MSI status of gastric cancer patients, researchers used image feature extraction technology and a machine learning algorithm to evaluate high-resolution histopathology pictures of patients. 279 cases of raw data were obtained from the TCGA database, 442 samples were obtained after preprocessing and upsampling, and 445 quantitative image features, including first-order statistics of impressions, texture features, and wavelet features, were extracted from the histopathological images of each sample. To filter the characteristics and provide a prediction label (risk score) for MSI status of gastric cancer, Lasso regression was utilized. The predictive label's classification performance was evaluated using a logistic classification model, which was then coupled with the clinical data of each patient to create a customized nomogram for MSI status prediction using multivariate analysis.
微卫星是人类基因组中广泛存在的小重复序列。微卫星不稳定性是肿瘤组织中重复单元插入或缺失引起的微卫星长度变化的现象(MSI)。MSI 型胃癌具有独特的遗传表型和临床病理特征,微卫星的稳定性影响胃间皮瘤患者是否对免疫治疗有反应。因此,在手术前确定 MSI 状态对于为胃癌患者制定治疗方案至关重要。传统的 MSI 检测方法需要免疫组织化学和遗传分析,这增加了成本,并且难以在临床实践中应用于每个患者。在这项研究中,为了预测胃癌患者的 MSI 状态,研究人员使用图像特征提取技术和机器学习算法来评估患者的高分辨率组织病理学图像。从 TCGA 数据库中获得了 279 例原始数据,经过预处理和上采样后获得了 442 个样本,并从每个样本的组织病理学图像中提取了 445 个定量图像特征,包括印象的一阶统计、纹理特征和小波特征。为了筛选特征并提供 MSI 状态的预测标签(风险评分),研究人员使用 Lasso 回归。然后使用逻辑分类模型评估预测标签的分类性能,然后将其与每个患者的临床数据相结合,使用多元分析创建用于 MSI 状态预测的定制列线图。