Lecture 1: The Leukemias Flashcards
How do the cells of acute vs. chronic leukemias differ?
- Acute = the cells represent immature precursor cells (blast cells)
- Chronic = the cells are more mature appearing
In older patients with mild pancytopenia and macrocytosis what should also be in the differential diagnosis?
Myelodysplasia or early AML
In acute leukemia (especially ALL) patients often present with what complaint?
Bone pain
What is Sweet’s Syndrome aka acute febrile dermatosis (AFND); and what is it associated with?
- Cutaneous manifestation of AML w/ biopsy demonstrating myeloblasts in the dermis (histiocytic variant of AFND)
- Can be confused with pyoderma gangrenosum
- Tx = management of AML
Auer rods are seen as azurophilic rods in the cytoplasm of cells in pt’s with what disorder?
AML
Gingival hypertrophy is most commonly seen in which variant of AML?
The M4 and M5 variants
Multiple smudge cells seen on peripheral smear are associated with what condition?
CLL
What are some of the known risk factors for developing AML?
- Exposure to radiation and benzene
- Chemotherapy, especially alkylating agents
Radiation is a risk factor for all leukemias except for?
CLL
When the leukocyte count is very high in pt with AML, the leukemic blasts can occlude the microcirculation leading to respiratory failure and cerebral dysfunction, this is known as what?
Leukostasis syndrome
How is the diagnosis of AML confirmed?
Bone marrow aspiration + biopsy showing >20% blasts
Which antigens expressed by myeloblasts can be used as markers for AML?
- CD34 (stem cell marker)
- HLA-DR
- CD33 and CD13
Which translocation is most frequently observed in children with AML?
t(8;21)
Most cases of AML with t(8;21) are classied as what type of AML; what is the prognosis in adults and children?
- AML w/ maturation
- Favorable prognosis in adults
- Poor prognosis in kids
Which genetic abnormality is seen in most causes of Acute Myelomonocytic Leukemia (AMML)?
inv(16); some have t(16;16)
Which tx do pt’s with AMML due to inv(16) or t(16;16) mutation have a good response to?
Intensive Chemotherapy
Which secondary mutation seen in AMML due to inv(16) mutations confers a poor prognosis?
KIT mutations
Recurring translocations involving 11q23.3 are seen in what type of AML; what is the prognosis?
Acute MONOcytic leuekmia; assoc. w/ poor outcome
FLT3-ITD mutations may occur in any subtype of AML, but are most common in which 2; what is the prognosis w/ this mutation?
APL and AML with normal karyotype; poor prognosis
Mutations of NPM1 are most often seen in what type of AML; prognosis?
- Most frequent in acute monocytic leukemia
- In absence of FLT3 mutations is assoc. w/ favorable prognosis
Pt’s with AML require immediate hospitilization for what?
- Placement of durable venous access (Hickman catheter, subcutaneous port)
- Initiation of chemotherapy
- Irradiated blood and platelet transfusion support
- If febrile and leukopenic, Abx for presumed infection
What is the standard chemotherapy induction regimen for AML?
- 3 days of an anthracycline, such as danorubicin or idarubicin
- 7 days of continous infusion of cytarabine (aka Ara-C)
Which complication may be seen in some patients during the initiation for AML?
Tumor lysis syndrome = abrupt necrosis of a large mass of leukemia cells and release of intracellular contents into circulation
After induction therapy for AML, patients with neutropenic fever should receive what therapy; what is done if there is persistent neutropenic fever following therapy?
- Should receive broad-spectrum Abx
- If there is persistent neutropenic fever despite Abx this warrants empiric ANTI-FUNGAL therapy
Older pt’s with AML that have significant comorbidities and high-risk cytogenic abnormalities have lower remission rates and are best treated how?
Palliatively, rather than w/ induction chemo
In addition to advanced age, poor performance status, and certain cytogenetic abnormalities, what are 2 other asssociations with AML that indicate a poor prognosis?
AML related to prior cancer chemo or a pre-existing myeloproliferative neoplasm or dysmyelopoietic syndrome
Describe the induction, consolidation, and maintenance phase of tx for AML?
- Induction: 3 + 7 (anthracycline and cytarabine aka Ara-C)
- Consolidation: high-dose Ara-C (HDAC)
- Maintenance: acute promyelocytic leukemia only w/ ATRA
Describe the induction, consolidation, and maintenance phase of tx for ALL?
- Induction: vincristine/prednisone plus others
- Consolidation: multiple agents plus CNS prophylaxis (MTX or Ara-C)
- Maintenance: 6-MP and MTX
ALL is a malignancy of B or T lymphoblasts and occurs most commonly in whom?
Children although may occur in adults, predominantly in 7th decade
Diagnosis of ALL requires what; examination of what is a essential part of the initial diagnostic evaluation?
- Presence of 20% or more lymphoblasts on BM exam
- CSF examination for evidence of CNS involvement is essential