Significant discoveries have been made in the past. Here is a summary of some of the most important discoveries of the past:
| 1946 | American Cancer Society Research Program begins. |
| 1947 | First successful chemotherapy for cancer. |
| 1953 | James Watson with Francis Crick discovers the double helical structure of DNA. |
| 1954 | Hammond-Horn study shows first link between smoking and lung cancer. |
| 1955 | Charles Huggins demonstrates that prostate and breast cancer are related to sex hormones. |
| 1966 | Henry Lynch describes the first hereditary cancer family syndrome. |
| 1968 | Donald Pinkel uses high-dose radiation and achieves 35% cure rate in childhood leukemia |
