ANNOUNCER: Patients with Chronic Myeloid Leukemia or CML face many decisions over the course of their treatment. Doctors don't have all the answers. So CML patients must collaborate in decision-making. That means patients must become well-educated about their disease and understand how their body responds to therapy.
STEPHEN O'BRIEN, MD, PhD: It's very important for patients to know the nature or the natural history of chronic myeloid leukemia because that must inform decision-making.
ANNOUNCER: First off, a patient must understand how CML , a cancer of the white blood cells may progress. In the early, or chronic phase of CML, the disease is stable, and the patient may experience no, or only mild symptoms, like fatigue. But later, low platelet counts may lead to uncontrolled bleeding. Too few normal white blood cells may lead to serious infection.
STEPHEN NIMER, MD: As the disease progresses, it becomes more difficult to treat and ultimately becomes untreatable. And so patients die not in the chronic phase of their disease, but from accelerated phase or blast phase disease.
STEPHEN O'BRIEN, MD: Well, clearly the most desirable treatment goal is to cure the patient with Chronic Myeloid Leukemia. At the moment, the only know curative therapy is a bone marrow transplant.
ANNOUNCER: CML patients must learn the factors that determine eligibility. For transplant. Age, overall health, tolerance for risk and the quality of a potential donor match.
STEPHEN NIMER, MD: And really, only about a third of patients will have a suitable donor for the transplant, which leaves the other two-thirds of the patients for whom transplantation is not really an option.
ANNOUNCER: So most patients discover their best goal in therapy falls short of "cure."
RICHARD STONE, MD: In general the goal of treatment of CML should be to lengthen life, lengthen good quality of life. In other words, the idea is to prolong the stable phase as long as possible.
ANNOUNCER: A patient undergoing drug therapy for CML must understand how his body's response is measured. There are three different kinds of tests, tracking hematologic, cytogenetic and molecular responses.
GWEN NICHOLS, MD: When we see that that the medicine treats the blood counts, we call this a hematologic response. When it returns the blood counts to what we consider a normal range.
ANNOUNCER: Some drugs, like interferon, have a deeper impact, reducing the number of cancerous cells containing the abnormal chromosome at the heart of the disease, the so-called Philadelphia chromosome.
STEPHEN NIMER, MD: And if more than two-thirds of the bone marrow, or the peripheral blood are in fact normal cells and not the CML cells, we would call that a major cytogenetic response. Now if we find no CML cells when we do the chromosome analysis, that's call a complete cytogenetic response.
ANNOUNCER: CML patients learn that doctors can also monitor the response to treatment at the molecular level, testing for signs of an aberrant gene called BCR-able which is found on the Philadelphia chromosome.
RICHARD STONE, MD: It's good to have a hematalogic response. It's better to have a chromosome response. It's better still to have a molecular response.
ANNOUNCER: CML patients and their doctors follow the results of these tests closely. Good responses at the chromosome and molecular levels correlate to longer survival.
STEPHEN O'Brien, MD, PhD: The goal of medical therapy is as far as possible to reduce the Philadelphia chromosome, the hallmark of chronic myeloid leukemia, as much as possible. Because previous studies with medical therapy have shown that survival of patients with a low level or with no detectable Philadelphia chromosome is considerably better than for those who have not had the Philadelphia chromosome reduced or eliminated.
ANNOUNCER: Patients must understand there can be setbacks, that drugs sometimes loose their efficacy.
JUDY OREM: And I'd taken interferon for two years, and they said that it really wasn't working very well. It had made some progress getting rid of the Philadelphia chromosome, but not a lot.
ANNOUNCER: Judy Orem entered a clinical trial for the drug imatinib, and she responded well. In three weeks, her hematologic tests were normal. In nine months, she was showing a good cytogenetic response.
Imantinib, known also by the brand name Gleevec blocks a protein in the leukemia cells, preventing them from multiplying. The drug has been approved only for treatment of CML when other therapies have failed. But a recent trial shows Gleevec is very effective for newly diagnosed patients as well.
STEVE MACKINNON, MD: The hematological response rates are greater than 90 percent and the complete cytogenetic response rates are between 60 and 70 percent in the treatment. And this is much better than any of the previous therapies that have been used for CML.
ANNOUNCER: CML patients quickly learn different drugs have different impact on their quality of life. Interferon requires daily injections and often brings about aches, fever and fatigue. Gleevec is taken as a pill, and generally has easily tolerated side effects, like weight gain, and puffiness around the eyes.
JUDY OREM: Now, those side effects are basically nothing by comparison. I have the energy. You know, I feel good. I don't sleep as much as I used to, but then I get more done.
STEVEN O'BRIEN, MD, PhD: One of the most striking things I've seen over the last few years in patients who are coming into my clinic who have been on interferon, for example and who are now on imatinib, is that they are transformed in may cases - going back to work, feeling well, going on holiday whereas they wouldn't have been doing those sorts of things on interferon.
ANNOUNCER: There are many effective therapies for Chronic Myeloid Leukemia. Choosing among them is often difficult. Experience shows, a patient does best when she understands the disease, and collaborates with her doctor on treatment decisions.