In 1910, a German scientist named Paul Ehrlich and his assistant, developed a treatment for syphilis named Salvarsan (606). This invention of a chemical synthetic drug in medical science led to the discovery of chemotherapy. Consistent, successful use of these cytotoxic drugs was unknown before 1945, and was still limited until 1950.
WWII and Chemotherapy
During World War II, there were toxic changes found in the bone marrow cells that develop into blood cells of naval personnel who were exposed to mustard gas during military duty. At the same time, the US Army was studying a number of chemicals related to mustard gas to develop more effective agents for war and other agents used for protective services. In the course of that work, a compound called nitrogen mustard was studied and found to work against a cancer of the lymph nodes called lymphoma. This compound was used as the model for a long series of similar but more effective agents, also known as alkylating agents, that killed rapidly growing cancer cells by damaging their DNA. The two Yale pharmacologists behind this discovery were Alfred Gilman and Louis Goodman.
The First Recorded Experiments
The two scientists began the experiment by working with mice in which the lymphomas were established. This showed that the tumors could be treated with the mustard agent and led to the first cases of human patients receiving the same type of treatments. The two men then teamed up with Gustav Linskog, a thoracic surgeon, and began injecting a more controlled dosage of the agent into a patient with non-Hodgkin’s lymphoma.
After recording the results of the process used on the patient, they found the masses to begin reducing significantly in size after just a few weeks. The patient had to return every few weeks for repeat treatments, which led to this being the first recorded experiment using cytotoxic agents for the treatment of cancer.
The Evolution of Chemotherapy
Post-WWII, more approaches to chemotherapy were discovered. Pathologist Sidney Farber from Harvard Medical School began to study the anticancer effect of folic acid, an essential vitamin in DNA metabolism. In 1948, Farber’s experiments led to the development of folate analogues, which were used to restore normal bone marrow in children with acute lymphoblastic leukemia, thus beginning the remission stage. More experiments with plant alkaloids in the 1950s and 1960s, like those from the vinca rosea plant, led to vinca alkaloids to be used as anticancer agents. These were used to create vinblastine, which is used to treat Hodgkin’s disease, and vincristine, the agent used to treat pediatric leukemia. Throughout the 1970s, 1980s and into the 1990s, more processes were created for earlier detection and treatments were made more customizable for different types of patients and their needs.
More recently in the past decade, with more medical advances than we have seen in the past century, doctors are able to identify cancer sooner, and scientists are still working to perfect the process of chemotherapy by making it safer and more effective for patients with more cancer type