Today, thousands of leukemia patients have a second chance at life because of the dedicated bone marrow research of Dr. E. Donnall Thomas (1920–2012).

Born on this day in Texas, Dr. Thomas became a quiet hero in humanity’s quest to find a cure for cancer.

Leukemia, once almost always fatal, is now often curable. Many lives are saved because of discoveries in bone marrow transplantation.

Healthy marrow injected into the bloodstream allows patients whose marrow has been destroyed by chemotherapy or radiation to produce new blood cells again. A miracle of modern medicine.

Thomas first pursued this research while still in medical school. In 1956, he successfully transplanted bone marrow between a leukemic patient and his identical twin. In 1969, he performed another transplant between relatives who were not identical twins. From there, he began exploring unrelated donor matches.

The journey was not easy. Many in the medical community were skeptical. “Back then,” Thomas explained, “we didn’t know anything about histocompatibility (tissue typing).”

Progress came slowly through improved tissue-typing techniques and the development of better antibiotics to control transplant infections.

Then in 1977, patient Laura Graves successfully received marrow from an unrelated donor. Her recovery helped open the door to national and international bone marrow donor registries.

In accepting the 1990 Nobel Prize in Medicine, Thomas humbly credited his colleagues and donated the $350,000 award to the Fred Hutchinson Cancer Research Center.

Today, more than 43 million people are listed as potential bone marrow donors worldwide. Because of the path Thomas helped pioneer, patients with leukemia and dozens of other diseases now have new hope and a second chance at life.