New Approaches to Adult Leukemia Give Hope
Monday April 22, 2002
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(Left to right) Donna Miale-Mayer, RN, BSN, MSN, OCN; Elizabeth Halton, RN, MS, ANP, OCN; and Erin Whelan, RN, MSN, OCN; at Memorial Sloan Kettering Cancer Center in NYC, discuss the acute care of an AML patient. Photo by Mark Paris.
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The nurses on the leukemia and lymphoma unit at Memorial Sloan-Kettering Cancer Center in New York City, have stories to tell. They know the 55-year-old woman who was found to have leukemia from the blood work drawn during a routine physical examination. They know the new mother who was diagnosed within months of delivering her first child. They know the father of two young boys who has been battling the disease for two years. They celebrate the successes. They mourn the losses.
"Leukemia," explains Elizabeth Halton, RN, MS, ANP, OCN, the adult nurse practitioner (APN) for the leukemia service, "is an incredibly life-threatening disease. It is a disease that overtakes your whole body. It is a disease that overtakes your life." While mortality has declined and five-year survival rates have increased among adults and children with certain forms of leukemia, for all forms of leukemia, the five-year survival rate was still only 46% in 2001. Over 28,800 new adult cases were diagnosed in the US that same year.1
Leukemia, together with lymphoma and multiple myeloma, are hematopoietic neoplasms or cancers of the blood-forming organs. Leukemias develop when a leukocyte transforms into a malignant cell. In leukemia, the cancerous cells are discovered in the blood and bone marrow. Eventually they can spread to the lymph nodes, brain, liver, and spleen. The most common leukemia types are grouped by how quickly the disease develops, and the type of white blood cell, lymphoid or myeloid, affected.
In acute leukemias the malignant cells are immature and incapable of performing immune system functions. The onset is rapid, and often fatal unless there is early treatment. Chronic leukemias develop in more mature cells that are still able to perform some of their tasks. Though the disease development is slower than the acute, chronic leukemias are often more difficult to cure.
"At any time, on any given day, we see a variety of these patients on our unit," Halton says, "but more often than not, our patients have the acute disease because they are, initially, the sickest. We do see the chronic form of the disease when these patients get into trouble, and we also have a group of patients who are referred to as having myelodysplastic syndrome. These are patients who are transforming into an acute leukemia."
"Acute myelogenous leukemia (AML) is the most common leukemia," adds Donna Miale-Mayer, RN, MSN, OCN, unit nurse leader on the leukemia/lymphoma unit, "it makes up 35% of all leukemias. That's the one we see most often in our adult population." Acute lymphcytic leukemia (ALL) is not as common in adults, but Halton says her patient population is about equally divided between the two acute forms. "It's because of the center that we are," she says, "it would be difficult to treat these patients in a local or community setting. Their transfusion and overall medical requirements are so intense. In many other settings, these patients would require ICU stays."
Vague Symptoms, Concise Diagnosis
In the early stage of leukemia, patients often seek medical attention for a cough or some kind of low-grade fever. The immune system is compromised and multiple treatments with antibiotics fail to help. "In fact, a lot of the patients complain that they just weren't feeling themselves," advises Erin Whelan, RN, MSN, OCN, clinical nurse specialist on the leukemia/lymphoma unit, "They feel as though they have had the flu or a cold that wouldn't go away."
Sometimes patients have no symptoms at all. Often the first suspicions arise with routine blood work. The 55-year-old woman at the routine physical had a white blood cell count of 85,000. "The white cell count can vary from really low to really high," Halton explains, "depending on the type of leukemia and even within the specific groups you can see a wide variation." The next step in the diagnoses is a bone marrow aspirate and biopsy, where a count of blasts or immature cells is done. Normally, blasts make up less than 5% of the bone marrow content, in leukemia blasts increase to between 30% and 100%.
From there, biopsied cells are studied to determine specific features. "Flow cytometry is used to identify surface markers (specific antigens) on the cells," Halton explains. "This starts to narrow down the field." Cytogenetics is one of the newest tools in leukemia diagnosis and treatment. "Here they can test for the different cytogenetics or chromosome changes that the cell may be expressing." Halton adds, "Certain ones are identified with specific leukemias."
The standard classification system for AML has been the French American British (FAB) system, in which AML subtypes are grouped according to a particular cell line in which the disease developed. "They still use this system," Halton says, "but along with that they have been able to identify certain genetic changes within the cells, some of which have helped identify a subtype of AML called acute promyelocytic leukemia, or APL. When treated early and quickly, APL has a great prognosis. If detected early, it's the one most easily treatable."
The analysis of the chromosomes is called the karyotype. This analysis, together with the FAB classification, will determine effective treatment as well as predict the course of the disease. "They can take the cytogenetics and identify what we call good prognostic factors and bad." Halton adds, "That helps determine not only the type of leukemia, but also the treatment. Investigators have been working on this for a full decade, but we are now seeing the impact of the genetics in diagnosis and treatment."
Treatment Progress
Treatment for adult leukemia has typically included chemotherapy, immunotherapy, and bone marrow transplantation. With information that is emerging about genetics, researchers are looking at new ways to control leukemia including approaches that can kill tumor cells directly, can inhibit the body's production of substances that promote their growth, or can enhance the immune response against leukemic cells.2 Thanks to the genetic understanding of APL, in which there is a translocation of genetic material between chromosomes 15 and 17, these patients receive a completely different treatment regimen. "ATRA (all-trans-retinoic acid), which is really vitamin A, is combined with chemotherapy. The ATRA helps the cell to normalize. This was a whole new revelation in how to deal with the cancer cell." explains Halton, "We have been able to pull that group out of the AML population and treat them specifically based on what their cytogenetics are." ATRA has increased the cure rate for APL from 40% to over 70% in just 10 years.1
Molecularly targeted agents have also shown promise in chronic myelogenous leukemia (CML). While studying CML, researchers noted a translocation between chromosomes 22 and nine. The identified fusion gene, bcr-abl, is expressed in about 95% of CML patients. Gleevec, one of the first oncogene-targeted drugs, given in pill form, has shown great promise in the treatment of the chronic-phase CML. Molecular analyses of other types of leukemias have now produced the identification of more than 100 additional oncogene targets that may eventually be available to similar drug development strategies.1
Good and poor prognostic factors determined by cytogenetics can also determine treatment options. "For patients with poor prognostic factors, you may opt not to treat them with standard chemotherapy and may, instead, treat with a higher-dose chemo and move them on fairly rapidly to bone marrow transplant," Halton adds.
In addition to the specific therapies, adjunctive treatments have also come a long way in helping patients tolerate the leukemia treatments. " The antibiotics have gotten better; the antifungals are better tolerated; and our treatments for nausea have greatly improved symptom management," notes Miale-Mayer, "We don't see people going through the difficult time that they used to."
Some Things Never Change
Diagnostics, treatment, and research aside, what doesn't change for the adult leukemia patient is the nursing care. "When it is all said and done," Whelan asserts, "It is the nursing care that gets these patients through the disease. It takes a specialized group of nurses to care for these patients. When the patients are admitted with AML, they are with us for a month. When they are neutropenic from treatment or disease, they won't manifest the normal signs of infection. Our nurses, who are so astute at caring for these patients, will pick up subtle changes very quickly."
But caring for leukemia patients is more than precise assessments and top-notch clinical skills. There is also the human factor. And perhaps that is where the real challenge of nursing care comes in, encouraging people to live their lives and in helping them to die.
"Acute leukemia can take over your life." Halton acknowledges. "Everything gets put on hold. Often patients will say to the nurses in amazement, 'My God, I was fine.' Part of the nursing job is to help people to focus so they can maintain their lives. One of our doctors says that leukemia is a great challenge, but also a great opportunity. I see what patients can endure. I always marvel at what the human spirit can master."
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