Eric S. Winer, M.D.
Hematology/Oncology (Leukemia, Lymphoma, and Myeloma), University Medicine Foundation
Rhode Island Hospital, The Miriam Hospital, Providence, Rhode Island
Blood cancers, including leukemia and lymphoma, are some of the most common types of cancer. Dr. Winer explains some recent advances in the field of leukemia treatment, specifically acute myelogenous leukemia (AML), the most common type of adult leukemia. These advances are helping leukemia patients to better handle treatment and improve their quality of life.
Q: How do you test for and diagnose leukemia?
A: If a person has symptoms of an illness, they may have a complete blood count done that shows abnormal cells not usually seen in a healthy person. But to confirm that a person has leukemia and what type of leukemia it is, there is really just one major test, a bone marrow biopsy. From the patient's hip, we remove a very small (1 cm) piece of bone and some marrow fluid and then test it. We actually look for markers on the surface of the cells and then determine whether or not they are leukemic. If they are, further testing is done to determine what type of leukemia it is and to look in even greater detail at the cell's chromosomes, helping us to move forward with treatment. Treatment for AML begins immediately. It is not the type of disease where you wait around to see what happens. The repercussions are severe if you do nothing. Once we make an initial diagnosis, the patient is admitted to the hospital for treatment.
Q: What does the treatment involve, and are there any advancements in that area?
A: The type of treatment is based on the patient. It depends on their age and how well we believe they will be able to handle the treatment based on their health and any other medical conditions they have. The most common initial treatment involves a combination of two chemotherapy drugs to destroy the leukemic cells. It is a very tough regimen, quite honestly. In the past, this type of chemotherapy treatment was not suitable to give to the elderly. If they started this type of treatment, they could get very sick or develop severe complications.
But, within the last five years, the field has advanced and new chemotherapy drugs have been developed that offer effective treatment but at lower doses, and with much less toxicity. These new combinations can be much more easily tolerated by older patients, or by younger patients who have other medical problems and would not be able to tolerate traditional chemotherapy. It's really become kind of a balancing act as we try to figure out what is the best combination of all of these drugs for each individual patient.
Q: What is the next step for leukemia patients after chemotherapy?
A: Well, hopefully, after the initial chemotherapy regimen, the leukemia will go into remission—a stage where there is no evidence of disease, even on tests like another bone marrow biopsy. That is the goal, of course. In fact, the complete remission success rate for adults with AML is between 68 and 72 percent. Even with a complete remission, further treatment is still necessary and may involve either three or four more cycles of chemotherapy or a bone marrow transplant.
Q: What is the long-term prognosis for leukemia patients, and what do you tell them after diagnosis?
A: I really believe that the word leukemia shouldn't carry the same fear that it did even 20 years ago. There is so much more optimism and hope today with the treatments that are available, and we are continuing to work towards improving response and survival rates. We see so many more success stories now, and patients can and do return to a productive life after treatment. Also, there is such a vast and excellent support network available, and many resources to turn to for information.
Q: What are some other advancements in the treatment of leukemia?
A: One area where real advancements have been made is in the treatment of chronic mylogenous leukemia (CML). [For reference, CML is the type of leukemia that former professional basketball player Kareem Abdul Jabbar recently announced he has.] We are now able to target individual genes for therapy. This has progressed from first identifying the leukemic cells to looking at the chromosomes of the cells, and then taking it a step further to be able to look at individual genes in those chromosomes. It is these genes that can become targets for successful therapy.
Specifically, there are drugs—Gleevec® is the most common—that target the specific gene and protein that causes the leukemia. Prior to Gleevec, CML patients had remission periods, but almost always had to have a bone marrow transplant for long-term survival. This targeted type of treatment has not been successful for AML yet. But through research and clinical trials, we are always trying to find ways to make improvements in this area.
I can't overstate the importance of trials in this situation. If we had a 99 percent response rate to treatment for AML and we were completely satisfied with the results, we wouldn't need trials. But the fact remains that while we have about a 70 percent response to treatment, there are still 30 percent of patients who do not have a successful remission. We are always looking for what we can do to better target our treatment and increase response.
Q: What is the most common type of leukemia in children?
A: Acute lymphocytic leukemia (ALL) is the most common type of leukemia in children. We're really not quite sure why that is, but children tend to respond much better in terms of treatment, response, and cure rates than adults. For instance, we even see dramatic differences in response in a 10-year-old child when compared to a 20-year-old. A child and an adult could have the exact same disease and the child will usually do better. Perhaps it's because they're better able to metabolize the chemotherapy drugs, but we don't know for certain.
Q: What are the differences in treatments between AML and ALL?
A: AML and ALL are very different diseases. While the treatment regimen for AML with chemotherapy alone could last about three or four months, the treatment regimen for ALL is just over two years. There is long-term maintenance therapy to prevent it from coming back. There is also more of a chance of relapse for adults who have ALL, and it is far harder to treat ALL in adults as compared to children.
