1 Department of Oncology, The First People's Hospital of Yinchuan, No. 2 Liqun West Street Xingqing District, Yinchuan, 750001, China.
2 Department of Oncology, The First People's Hospital of Yinchuan, No. 2 Liqun West Street Xingqing District, Yinchuan, 750001, China. vwyjkym@163.com.