What are the role of Reed-Sternberg cells in Hodgkin Lymphoma?
Release factors that induce the accumulation of reactive lymphocytes, macrophages, and granulocytes
Activation of which TF is a common event in class Hodgkin Lymphoma?
The lacunar variant of Reed-Sternberg cells are associated with what subtype of HL?
Nodular sclerosis subtype
What markers are expressed by Reed-Sternberg cells in the "classical" subtypes of HL vs. the lymphocyte predominant subtype?
- Classical = CD15+ and CD30+ and PAX5+
- Lymphocyte predominant = CD20+ and BCL6
The nodular sclerosis type of HL has a propensity to involve which strucutres; most commonly in whom?
Lower cervical, supraclavicular, and mediastinal nodes of adolescents and young adults
Which 3 subtypes of HL are most often associated with EBV?
- Mixed cellularity type
- Lymphocyte depletion type
Which subtype of HL has the worst overall prognosis?
Lymphocyte depletion type
The mixed cellularity type of HL arises most often in what age groups and has a predominance for what sex?
- Biphasic age distribution (peaks in young adults and then older adults)
- Male predominance
Common presenting features of mixed cellularity type of HL?
Commonly has systemic sx's, such as night sweats and weight loss
How is the lymphocyte-rich type of HL distinguished from the lymphocyte predominant subtype?
By presence of mononuclear variants and diagnostic Reed-Sternberg cells w/ a "classical" immunophenotypic profile
The lymphocyte depleted type of HL occurs most frequently in whom?
More common in older males, HIV-infected, and developing countries
Describe the morphology of the Reed-Sternberg cell variants found in the lymphocyte predominant type of HL.
- Multilobed nucleus resembling popcorn kernel ("popcorn cell")
- Known as lymphohistiocytic variant
Majority of patients with lymphocyte predominant type of HL are what sex/age; how do they present?
Typically males, usually <35 y/o presenting w/ cervical or axillary LAD
Which 2 subtypes of HL are more likely to be (stage III-IV) and present with sx's such as fever, night sweats and weight loss?
- Mixed-cellularity type
- Lymphocyte depletion type
What is the most important prognostic variable for HL with current treatment protocols?
How is stage II vs. stage III HL and NHL classified?
- Stage II: involvement of 2+ LN regions on same side of diaphragm
- Stage III: involvement of LN regions on both sides of diaphragm
Diagnosis of Acute Myeloid Leukemias (AML) is based on what?
Presence of >20% myeloid blasts in the bone marrow
What are the 2 most common chromosomal rearrangements seen in AML?
t(8;21) and inv(16)
Acute promyelocytic leukemia (APL - M3) is associated with what translocation?
What is seen morphologically in Acute promyelocytic leukemia (APL); high incidence of what complication?
- Numerous Auer rods, often in budles within individual progranulocytes
- Primary granules very prominent
- High incidence of DIC
AML with what genetic aberration is associated with a poor prognosis?
Translocations involving MLL on chromosome 11q23
AML with t(11q23;v); diverse MLL fusion genes usually shows some degree of what differentiation?
How does AML with t(8;21) differ from those with inv(16) rearrangements in terms of morphology?
- t(8;21): shows full range of myelocytic differentiation; Auer rods easily found = AML w/ myelocytic maturation (M2 subtype)
- inv(16): myelocytic and monocytic differentiation; abnormal eosinophilic precursors w/ abnormal basophilic granules = AML w/ myelomonocytic maturation (M4 subtype)
Prognosis of AML w/ MDS-like features?
AML with monocytic maturation is characterized by what clinically?
High incidence of organomegaly, LAD, and tissue* infiltration
Which type of AML is represented by the FAB class M1, M2, M3, and M4?
- M1 = AML without maturation; ≥3% blasts MPO (+)
- M2 = AML with myelocytic maturation - t(8;21)
- M3 = Acute Promyelocytic leukemia - t(15;17) - P and 3
- M4 = Acute myelo-monocytic leukemia - inv(16) - has 4 letters
How do myeloblasts differ from monoblasts in terms of staining?
- Myeloblasts = MPO (+) = have Auer rods
- Monoblasts = nonspecific esterase (+) = lack Auer rods
Which CD markers are positive on myeloid blasts?
CD34(+) and CD33 (+)
What are the most common presenting signs/sx's of AML?
- Fatigue (anemia) + bleeding (thrombocytopenia) + fever/infection (neutropenia)
- Spontaneous mucosal and cutaneous bleeding very common
Fungal skin infections, leukemia cutis, orbital granulocytic sarcoma, and infiltration of the gingiva are common features of which type of AML?
Acute monocytic leukemia (M5a/b); any with monocytic differentiation