Journal of the American Academy of Physician Assistants:
Quick Recertification Series
Gore, Jill M. MPAS, PA-C
Jill M. Gore practices primary care in San Antonio, Tex. The author has indicated no relationships to disclose relating to the content of this article.
Dawn Colomb-Lippa, MHS, PA-C, and Amy M. Klingler, MS, PA-C, department editors
* Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by overproduction of mature, but abnormal, myeloid white blood cells (WBCs).
* Chronic lymphocytic leukemia (CLL) is a clonal malignancy of B cells, leading to an accumulation of lymphocytes that are immunoincompetent and are unable to adequately respond to presenting infections.
* CML and CLL follow an indolent course. Patients rarely notice symptoms of their illness and the malignancy is frequently an incidental finding on routine complete blood cell (CBC) count.
* Both disorders affect middle-aged to older adults, with most patients diagnosed between ages 50 and 65 years.
* In developed countries, CLL is the most common form of leukemia in adults.
* CML is one of only a few cancers known to be linked to a specific gene mutation, the reciprocal translocation on the long arms of chromosomes 9 and 22 known as the Philadelphia chromosome.
* Patients with CML present at various stages of the disease and transition between various stages.
* Chronic phase: patients have a gradual rise in WBC count. In peripheral blood, blasts compose less than 15% of the WBC count. Splenomegaly, weight loss, and B symptoms (fever, night sweats, and weight loss) may be present.
* Accelerated phase: patients with previously controlled disease develop worsening blood counts. Fifteen percent to 30% of peripheral blood is composed of blasts. Organomegaly develops. A new chromosomal abnormality may be acquired.
* Blastic phase: patients have signs and symptoms of acute leukemia, including bone pain and B symptoms. An increased number of blasts are found in the peripheral blood and bone marrow, with more than 30% blasts being diagnostic for this phase.
* Patients frequently are asymptomatic; leukocytosis is an incidental finding on a CBC count.
* Symptoms, if present, include fatigue, weight loss, night sweats, low-grade fever, recurring infections, abdominal fullness, early satiety, and lymphadenopathy.
* Physical examination findings may include hepatosplenomegaly, sternal tenderness, and lymphadenopathy.
* CML: patients will have an elevated WBC count on CBC count. Anemia and thrombocytopenia may be present. Confirmation of diagnosis is made by bone marrow biopsy. Hypercellularity with expansion of the myeloid cell line will be noted. The Philadelphia chromosome, which is pathognomonic for CML, will be present in 95% of patients.
* CLL: patients will have a high WBC count on CBC count. Peripheral blood flow cytometry and bone marrow biopsy will confirm the diagnosis. An ultrasound of the liver and spleen may be performed. If the patient has had frequent infections, immunoglobulin testing may be indicated.
* Patients who are asymptomatic do not require treatment. Treatment is indicated for patients whose WBC count is greater than 100x109/L, who have worsening anemia or thrombocytopenia, or who develop symptoms including fever, enlarged lymph nodes, or hepatosplenomegaly.
* Treatment for CLL typically includes a combination of chemotherapy, a monoclonal antibody (such as rituximab), and/or prednisone.
* Since 2001, tyrosine kinase inhibitors have been indicated as first-line treatment for CML. These include imatinib, dasatinib, nilotinib, bosutinib, and ponatinib.
* The only known curative therapy is an allogenic stem cell transplant.
© 2014 American Academy of Physician Assistants.