Blood cancer is actually a term applied to three different types of cancer – leukemia, lymphoma and myeloma. For centuries, these cancers had virtually no possibility of survival. Even as recently as the 1960s, the five-year survival rate for leukemia was 14%. By 2010, it had increased to 61%. Similar gains have been made in the survival rates for lymphoma and myeloma, with Hodgkin lymphoma reaching a five-year survival rate of 88% in that year. The story of the science behind the gains in survival rates and the development of ever-more effective therapies is the story of advances in the field of immunotherapy and personalized medicine taking place at centers such as Abramson at UPENN and Dana-Farber in Boston.
The first significant increases in survival rates occurred in the early 1980s, with the introduction of chemotherapy and bone marrow transplants. In a UPENN CureTalks interview in 2017, Dr. Carl June of UPENN described the two-step process. First, the patient’s immune system received super-lethal doses of chemotherapy. Then, bone marrow from a sibling was transplanted into the patient. When the result was a better survival rate, the increase in survival was attributed to the super-lethal dose of chemotherapy administered prior to the transplant. When the procedure was performed on identical twins and researchers discovered that increased survival did not occur, researchers had to rethink their premise. They realized that the source of the survival increase lay in the differences in the marrow of the non-identical sibling rather than in the process of destroying the patient’s immune system before the introduction of new bone marrow.