What is the meaning of disease progression?
<answer> Progressive disease is a term that describes a disease that is progressing or worsening. <context> Progressive disease is a term that describes a disease that is progressing or worsening. With cancer, progressive disease is defined as at least a 20 percent growth in the size of the tumor or spread of the tumor since the beginning of treatment. In other words, if the size of a tumor is 20 percent larger on a scan it would be called progressive disease.