Noise-induced first-order transition in anti-tumor immunotherapy
  We studied the single-variable dynamics model of the tumor growth. A first-order phase transition induced by an additive noise is shown to reproduce the main features of tumor growth under immune surveillance. The critical average cells population has a power-law function relationship with the immune coefficient. 
Wei-Rong Zhong, Yuan-Zhi Shao, and Zhen-Hui He