The outlook for patients with leukemia and other life-threatening blood cancers is rapidly improving thanks to targeted therapies and advancements in blood and marrow transplants, researchers say.
But while breakthroughs are improving patients' quality of life, a cure for blood cancers is more problematic. "There are so many different kinds of cancer and they seem to find their way around the innovations that we develop," said Dr. Leslie Popplewell, an associate clinical professor, researcher and staff physician at City of Hope, a cancer research hospital in Duarte.
The Leukemia & Lymphoma Society estimates 156,420 people in the U.S. will be diagnosed with leukemia, lymphoma or myeloma this year, accounting for 9.4% of all new cancer cases. More than 55,000 people will die this year from the diseases.
Popplewell and others say the prognosis for blood cancer patients is far more promising than just a generation ago. Targeted therapies, for example, can hold certain blood cancers in check for years. Cellular immunotherapy, meanwhile, has alleviated the need for harsh radiation and chemotherapy by taking T cells — or T lymphocytes that mature in the thymus — from a cancer patient and programming them through genetic engineering before reinfusing the modified cells into the patient to attack the cancer.
"Although not curative, [targeted therapies] provide amazing, relatively nontoxic disease control for chronic myelogenous leukemia and now will probably do so, to a lesser extent, for chronic lymphocytic leukemia," said Dr. James Mason of Scripps Health in La Jolla. "There are also some exciting new antibody therapies – immune therapy – for CLL."
Mason heads the blood and marrow transplantation program at Scripps' Green Hospital, and he notes the survival rate among patients undergoing such procedures has more than doubled since Scripps Health founded San Diego County's first blood and marrow transplantation program in 1980.
"I have seen an amazing transformation of blood and marrow transplantation for acute leukemias," Mason said. "Using genomics we can better identify donors and that, coupled with over 10 million donors in the U.S. and around the world, means that most patients can find a lifesaving stem cell donor within a few months."
Popplewell agrees that patients with chronic myelogenous leukemia today face a much-improved prognosis thanks to advances in research. "Some of these diseases such as CML can be held in check for a very long time," she said.
In fact, five-year survival rates have increase dramatically from 40 years ago. From 1960 to 1963, for example, just 14% of leukemia patients survived more than five years. From 2003 to 2009, that jumped to 59%.
"We still have a long way to go," Mason said. "But each year, the outcomes improve."