Peter C. Nowell’s research continues to help impact how biologist observe tumor cells withusing Darwin’s Theory of Evolution to help researchers better understand cancer cells and howwe can counter their effects on the human body such as chemotherapy and other methods ofeliminating them. With chemotherapy being the most known method of treatment, there isanother method that is much safer and recently left clinical trials called immunotherapy. Bydiscussing Nowell’s research we review clonal evolution in which he explains how tumor cellsare produced along with other researchers who have discussed the progression of tumor cells.With these studies explaining more how cancer cells work, will benefit future methods to deliverbetter and safer treatments for patients.