QUICK RECERTIFICATION SERIES
Acute leukemias Jill M. Gore, MPAS, PA-C
GENERAL FEATURES • Acute lymphoblastic (or lymphocytic) leukemia (ALL) and acute myeloid (or myelogenous) leukemia (AML) are malignant disorders of the bone marrow resulting in excessive, uncontrolled production of immature white blood cells (WBCs). • Most cases of acute leukemia have an idiopathic cause. However, risk factors include previous exposure to radiation, certain toxins such as benzene, and chemotherapy. Trisomy 21 predisposes patients to an increased risk of ALL by 15-fold. AML is more common in patients with certain genetic disorders, with preexisting hematologic disorders, and with a history of chemotherapy treatment. • ALL is the most common childhood malignancy, with a peak incidence between the ages of 2 and 9 years. ALL accounts for 80% of childhood leukemia but only 20% of adult leukemia. Unlike childhood ALL, which is curable, adult ALL carries a poor prognosis. • AML is more common in adults with a median age of 60 years at presentation. • Identifying genetic mutations, including chromosomal translocations, deletions, and inversions, is important in determining treatment and clinical outcomes in patients diagnosed with AML. In addition to age, certain karyotypes are known to carry a favorable, intermediate, or unfavorable prognosis. • According to the National Cancer Institute (NCI), the remission rate for children with ALL is over 95%. Children with ALL have an 80% likelihood of cure; this rate decreases in adolescents. In adults, prognosis is poor, with a cure rate of about 40%. • Patients over age 60 years with AML have a median survival of less than 1 year. Patients under age 60 years typically achieve a complete remission. However, relapse is common, and 5-year survival is less than 50%.
Jill M. Gore practices primary care in San Antonio, Tex. The author has disclosed no potential conflicts of interest, financial or otherwise. Dawn Colomb-Lippa, MHS, PA-C and Amy M. Klingler, MS, PA-C, department editors DOI: 10.1097/01.JAA.0000446221.55059.49
CLINICAL ASSESSMENT • Symptoms are present for only a short time, typically days to weeks, and are related to pancytopenia. Neutropenia may lead to bacterial or fungal infection, such as cellulitis, pneumonia, or perirectal infection. Excessive blast production may produce symptoms of gum hypertrophy and, more often in children, bone pain. Patients frequently complain of easy bruising and prolonged bleeding. Gingival bleeding, epistaxis, or menorrhagia may be noted. • On examination, patients appear pale and fatigued and may have petechiae, purpura, gum hypertrophy, hepatosplenomegaly, and lymphadenopathy. Patients may have fever, focal infection, and dyspnea. Bone tenderness may be elicited, especially in the sternum, tibia, and femur. • Lumbar puncture is required for patients who have ALL to evaluate for the presence of meningeal leukemia. DIAGNOSIS • A complete blood cell count reveals the hallmark finding of pancytopenia with circulating blasts. • A bone marrow biopsy confirms the diagnosis and reveals a hypercellular marrow with either excess lymphoblasts, as in ALL, or excess myeloblasts, as in AML.
QUESTIONS 1. Which finding is pathognomonic in AML? a. smudge cell b. Auer rod c. Philadelphia chromosome d. Howell-Jolly body 2. Which percentage of blasts is diagnostic for acute leukemia? a. >5% b. >10% c. >15% d. >20%
Copyright © 2014 American Academy of Physician Assistants
JAAPA Journal of the American Academy of Physician Assistants
www.JAAPA.com
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
47
QUICK RECERTIFICATION SERIES
1. B. An Auer rod is pathognomonic for AML. Smudge cells are commonly seen with CLL; Philadelphia chromosome with CML; and Howell-Jolly bodies with sickle cell anemia.
Answers
TREATMENT • Acute leukemia can progress rapidly, over weeks to months. Without prompt diagnosis and treatment, acute leukemia can be fatal. • ALL Combination chemotherapy is divided into the following phases: induction, consolidation, central nervous system (CNS) sterilization, and maintenance. Total treatment time is 2 to 3 years. Because of the high risk for CNS disease, patients with ALL undergo CNS-directed therapy, which typically includes intrathecal chemotherapy, CNS-directed systemic chemotherapy (such as dexamethasone or methotrexate), and/or cranial radiation. Allogeneic stem cell transplant is performed either in the first or second remission, depending on the patient’s age.
• AML Treatment with combination chemotherapy is divided into two phases: induction and consolidation. The goal of induction chemotherapy is to achieve a remission, defined as fewer than 5% blasts in the bone marrow. Because nearly all patients have residual disease and the risk of relapse is high with induction chemotherapy alone, consolidation chemotherapy is part of the standard treatment regimen. The goal of this phase is to eliminate undetectable malignant cells, improve survival, and prevent relapse. Allogeneic stem cell transplant provides the highest probability of remission and cure and the lowest risk of recurrence. JAAPA 2. D. According to the WHO, >20% blasts in the circulating blood or the bone marrow is diagnostic for acute leukemia.
• According to the World Health Organization (WHO), greater than 20% blasts on bone marrow or in peripheral blood is diagnostic of acute leukemia. • An Auer rod may be seen on peripheral smear and is pathognomonic of AML.
Official journal jou of the American Academy of Physician Assistants
The official journal of AAPA — and the leading journal for the physician assistant profession — is now published by Lippincott Williams & Wilkins. Featuring a fresh, contemporary design and a state-of-the-art website, each monthly issue of JAAPA delivers informative, educational content, including: Q
Clinical review articles
Q
AAPA-approved Category I CME
Q
Case reports
Q
Clinical departments
Q
Original research
JAAPA is an AAPA member benefit. Members enjoy professional development resources that keep their careers on track. Join AAPA today to start receiving the award-winning JAAPA. Visit aapa.org/join. 4-K116
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Volume 27 • Number 5 • May 2014
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Acute leukemias Jill M. Gore, MPAS, PA-C
GENERAL FEATURES • Acute lymphoblastic (or lymphocytic) leukemia (ALL) and acute myeloid (or myelogenous) leukemia (AML) are malignant disorders of the bone marrow resulting in excessive, uncontrolled production of immature white blood cells (WBCs). • Most cases of acute leukemia have an idiopathic cause. However, risk factors include previous exposure to radiation, certain toxins such as benzene, and chemotherapy. Trisomy 21 predisposes patients to an increased risk of ALL by 15-fold. AML is more common in patients with certain genetic disorders, with preexisting hematologic disorders, and with a history of chemotherapy treatment. • ALL is the most common childhood malignancy, with a peak incidence between the ages of 2 and 9 years. ALL accounts for 80% of childhood leukemia but only 20% of adult leukemia. Unlike childhood ALL, which is curable, adult ALL carries a poor prognosis. • AML is more common in adults with a median age of 60 years at presentation. • Identifying genetic mutations, including chromosomal translocations, deletions, and inversions, is important in determining treatment and clinical outcomes in patients diagnosed with AML. In addition to age, certain karyotypes are known to carry a favorable, intermediate, or unfavorable prognosis. • According to the National Cancer Institute (NCI), the remission rate for children with ALL is over 95%. Children with ALL have an 80% likelihood of cure; this rate decreases in adolescents. In adults, prognosis is poor, with a cure rate of about 40%. • Patients over age 60 years with AML have a median survival of less than 1 year. Patients under age 60 years typically achieve a complete remission. However, relapse is common, and 5-year survival is less than 50%.
Jill M. Gore practices primary care in San Antonio, Tex. The author has disclosed no potential conflicts of interest, financial or otherwise. Dawn Colomb-Lippa, MHS, PA-C and Amy M. Klingler, MS, PA-C, department editors DOI: 10.1097/01.JAA.0000446221.55059.49
CLINICAL ASSESSMENT • Symptoms are present for only a short time, typically days to weeks, and are related to pancytopenia. Neutropenia may lead to bacterial or fungal infection, such as cellulitis, pneumonia, or perirectal infection. Excessive blast production may produce symptoms of gum hypertrophy and, more often in children, bone pain. Patients frequently complain of easy bruising and prolonged bleeding. Gingival bleeding, epistaxis, or menorrhagia may be noted. • On examination, patients appear pale and fatigued and may have petechiae, purpura, gum hypertrophy, hepatosplenomegaly, and lymphadenopathy. Patients may have fever, focal infection, and dyspnea. Bone tenderness may be elicited, especially in the sternum, tibia, and femur. • Lumbar puncture is required for patients who have ALL to evaluate for the presence of meningeal leukemia. DIAGNOSIS • A complete blood cell count reveals the hallmark finding of pancytopenia with circulating blasts. • A bone marrow biopsy confirms the diagnosis and reveals a hypercellular marrow with either excess lymphoblasts, as in ALL, or excess myeloblasts, as in AML.
QUESTIONS 1. Which finding is pathognomonic in AML? a. smudge cell b. Auer rod c. Philadelphia chromosome d. Howell-Jolly body 2. Which percentage of blasts is diagnostic for acute leukemia? a. >5% b. >10% c. >15% d. >20%
Copyright © 2014 American Academy of Physician Assistants
JAAPA Journal of the American Academy of Physician Assistants
www.JAAPA.com
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
47
QUICK RECERTIFICATION SERIES
1. B. An Auer rod is pathognomonic for AML. Smudge cells are commonly seen with CLL; Philadelphia chromosome with CML; and Howell-Jolly bodies with sickle cell anemia.
Answers
TREATMENT • Acute leukemia can progress rapidly, over weeks to months. Without prompt diagnosis and treatment, acute leukemia can be fatal. • ALL Combination chemotherapy is divided into the following phases: induction, consolidation, central nervous system (CNS) sterilization, and maintenance. Total treatment time is 2 to 3 years. Because of the high risk for CNS disease, patients with ALL undergo CNS-directed therapy, which typically includes intrathecal chemotherapy, CNS-directed systemic chemotherapy (such as dexamethasone or methotrexate), and/or cranial radiation. Allogeneic stem cell transplant is performed either in the first or second remission, depending on the patient’s age.
• AML Treatment with combination chemotherapy is divided into two phases: induction and consolidation. The goal of induction chemotherapy is to achieve a remission, defined as fewer than 5% blasts in the bone marrow. Because nearly all patients have residual disease and the risk of relapse is high with induction chemotherapy alone, consolidation chemotherapy is part of the standard treatment regimen. The goal of this phase is to eliminate undetectable malignant cells, improve survival, and prevent relapse. Allogeneic stem cell transplant provides the highest probability of remission and cure and the lowest risk of recurrence. JAAPA 2. D. According to the WHO, >20% blasts in the circulating blood or the bone marrow is diagnostic for acute leukemia.
• According to the World Health Organization (WHO), greater than 20% blasts on bone marrow or in peripheral blood is diagnostic of acute leukemia. • An Auer rod may be seen on peripheral smear and is pathognomonic of AML.
Official journal jou of the American Academy of Physician Assistants
The official journal of AAPA — and the leading journal for the physician assistant profession — is now published by Lippincott Williams & Wilkins. Featuring a fresh, contemporary design and a state-of-the-art website, each monthly issue of JAAPA delivers informative, educational content, including: Q
Clinical review articles
Q
AAPA-approved Category I CME
Q
Case reports
Q
Clinical departments
Q
Original research
JAAPA is an AAPA member benefit. Members enjoy professional development resources that keep their careers on track. Join AAPA today to start receiving the award-winning JAAPA. Visit aapa.org/join. 4-K116
48
www.JAAPA.com
Volume 27 • Number 5 • May 2014
Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
