改进支持向量机分类方法及其在原发性肝癌筛查中的应用

为了尽早检测出原发性肝癌患者，辅助医生进行医疗决策，提高患者临床疗效，提出一种基于临床常规检验指标的筛查方法。该方法使用支持向量机建模，采用差异进化算法进行参数优化，以接收者操作特征曲线下面积的值作为模型评价测度，将得到的最优模型用于检验数据识别，以判断该数据属于健康、良性病变还是原发性肝癌。此外，还根据临床需求绘制分类模型的性能指标曲线和阈值查找表，由用户选择阈值，使预测性能进一步提升。实验结果表明：与其他5种分类方法相比，该方法建立的模型具有更好的性能，其准确度可达0.94，Kappa系数可达0.90。研究结果可辅助医生进行原发性肝癌早期筛查，提高患者长期生存率。

Classification Method of Improved Support Vector Machine and Its Application in Early Detection of Primary Liver Cancer

To screen out primary liver cancer patients as early as possible, assist doctors to make better decisions and improve treatment effects, an early screening method based on routine laboratory data is proposed. To test the classification of healthy, benign lesions or primary liver cancer, a support vector machine method is optimized by using a differential evolution algorithm, in which the evaluation cost is the area under the ROC (receiver operating characteristic) curve. Moreover, to satisfy different clinical requirements, performance index curves and cut-off lookup tables of the training model are built, then cut-off values are selected by users to further improve the prediction performance. Compared with other 5 state-of-the-art methods, the proposed methods have better classification performance, of which the accuracy reaches 0.944 1, and the Kappa coefficient reaches 0.903 1. The research results can assist doctors to screen out the primary liver cancer early and improve the long-term survival rate of patients.