- Acute leukemias are the most common malignancies in children and the leading cause of cancer-related death in patients younger than age 35 years.
- To establish a definitive diagnosis of acute leukemia, the following diagnostic components are required: bone marrow biopsy and aspirate (with >20% blasts), cytogenetics, and immunophenotyping.
- Several risk factors correlate with prognosis for acute lymphoblastic leukemia (ALL). Poor prognostic factors include high white blood cell count at presentation, very young or very old age at diagnosis, delayed remission induction and presence of certain cytogenetic abnormalities (e.g., Philadelphia chromosome positive [Ph+]).
- For children with ALL, remission induction therapy includes vincristine, a corticosteroid, and asparaginase, with or without an anthracycline. For adults with ALL, vincristine, prednisone, and an anthracycline are given, and asparaginase is sometimes added.
- All patients with ALL require prophylactic therapy to prevent CNS disease because of the high risk of central nervous system relapse. The choice for therapy includes a combination of the following: cranial irradiation, intrathecal chemotherapy, or high-dose systemic chemotherapy with drugs that cross the blood–brain barrier.
- Long-term maintenance therapy for 2 to 3 years is essential to eradicate residual leukemia cells and prolong the duration of remission. Maintenance therapy consists of oral methotrexate and mercaptopurine, with or without monthly pulses of vincristine and a corticosteroid.
- Disease-free survival is lower in adults with ALL and has been attributed to greater drug resistance, poor side effect tolerance with subsequent nonadherence, and possibly less-effective therapy. This population is also more likely to have Ph+ ALL, which is associated with a worse outcome, but the use of tyrosine kinase inhibitors has improved treatment results.
- There are several poor prognostic factors for adult acute myeloid leukemia (AML): older age, organ impairment, presence of extramedullary disease, and presence of certain cytogenetic and molecular abnormalities.
- Therapy of AML usually includes induction therapy with an anthracycline and cytarabine. Postremission therapy is required in all patients and can include either consolidation chemotherapy with or without maintenance therapy, or hematopoietic stem cell transplantation.
- It is estimated that up to 108 to 109 malignant cells remain following attainment of a complete remission. Postremission therapy with either chemotherapy or hematopoietic stem cell transplantation is essential in AML.
- Treatment of acute promyelocytic leukemia consists of induction therapy, followed by consolidation and maintenance therapy. Induction includes tretinoin and an anthracycline; consolidation therapy consists of two to three cycles of anthracycline-based therapy; maintenance consists of pulse doses of tretinoin, mercaptopurine, and methotrexate for 2 years.
- Hematopoietic growth factors can be safely and effectively used with myelosuppressive chemotherapy for acute leukemias. The benefits may include reduced incidence of serious infections, reduced hospital stays, and fewer treatment delays, but do not include prolonged disease-free survival or overall survival.
On completion of the chapter, the reader will be able to:
Identify risk factors associated with a poor prognosis in acute lymphoblastic leukemia.
Compare the clinical presentation of acute myeloid leukemia and acute lymphoblastic leukemia.
Compare the clinical course ...