Lymphoid Neoplasms II Flashcards
What are the 2 most common mature B cell neoplasms?
Diffuse large B cell lymphoma and Follicular lymphoma
What is the most common leukemia in the US?
CLL or SLL
Explain CLL or SLL.
Accumulation of naiveB cell, CLL is mainly in the bone marrow whereas SLL is confined to lymph nodes.
* Age: > 60 years.
* Most common adult leukemia.
* CD20+, CD5+ B-cell neoplasm.
* Often asymptomatic, progresses slowly
* Smudge cells B in peripheral blood smear Complications of SLL/CLL are
* Autoimmune hemolytic anemia.
Richter transformation—SLL/CLL transformation into an aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL).
* Hypogammaglobulinemia, leading to immunosuppressive state
What are the clinical features of CLL/SLL.
- Assymptomatic
- Anemia
- Thrombocytopenia
- Lymphadenopathy
- Immunologic abnormalities - autoimmune hemolytic anemia, thrombocytopenia, hypogammaglobulinemia.
What are the pathological findings of SLL/CLL.
- Lymphocytosis - we see smudge cells on peripheral smear In lymph nodes we see diffuse infiltrate of small round lymphocytes.
What cell markers are observed in CLL/SLL.
CD19+, CD20+, CD5+, CD10-, sIg+ (clonal)
Explain the genetics involved in CLL/SLL.
About half of the SLL/CLL cases involve Ig gene rearrangment but no somatic hypermutation in IgVH.Mutated CLL/SLL has Ig gene rearrangment with somatic hypermutation.Other chromosomal abnormalities may involve 13q deletion.
CLL/SLL course and prognosis.
Median survival 6 y
- Worse for U-CLL/SLL (3 y) than for M-CLL/SLL (>7 y) Prolymphocytic transformation –15-30%
- > 10% prolymphocytes
- Increased splenomegaly
- Mean survival <2 y Richter transformation –5-10%
- Large cell lymphoma
- Increased lymphadenopathy
- Mean survival <1 y
Explain hairy cell leukemia.
- Age: Adult males.
- Mature B-cell tumor. Cells have lamentous, hair-like projections.
- Causes marrow fibrosis, dry tap on aspiration.
- Patients usually present with massive splenomegaly.
- Stains TRAP (tartrate-resistant acid phosphatase) ⊕. TRAP stain largely replaced with flow cytometry.
- Treatment: cladribine, pentostatin.
What are the clinical features of hairy cell leukemia?
Hairy Cell Leukemia Clinical Features
- Initially asymptomatic
- Splenomegaly - May be massive
- Hepatomegaly
- Pancytopenia
- Infections
- Indolent course
What are the pathological findings of hairy cell leukemia?Explain immunophenotype, cytochemistry and genetics of this disease
- We see ‘hairy cells’ - lymphocytes with villous cytoplasmic projections.
- Absolute monocytopenia
- Bone marrow shows increased reticulin fibrosis
- Spleen has enlarged red pulp.
On immunophenotyping we see CD11c+. CD25+, CD103+ and Annexin A1.Cytochemistry: Tartrate resistant acid phsophataseGenetics - BRAF mutation.
Explain follicular lymphoma.
- Very common lymphoma in US
- Middle aged to older adults
- t(14;18)—translocation of heavy-chain Ig (14) and BCL-2 (18). BCL2 inhibits apoptosis
- Hepatosplenomegaly
- Indolent, chronic course –median survival 7-9 y Presents with painless “waxing and waning” lymphadenopathy Follicular architecture: small cleaved cells (grade 1), large cells (grade 3), or mixture (grade 2).
What do we see on lymph nodes H&E in follicular lymphoma?Explain the genetics and immunophenotyping of FL.
Nodular infiltrate of small, cleaved lymphocytes with admixed large cells, also the mantle zone is markedly diminished or absent.Genetics - t(14;18), overexpression of BCL2 protein prevents apoptosisImmunophenotyping - CD19+, CD20+, CD10+, CD5-, sIg+ (clonal)
What is the most common lymophoma in the US?
Diffuse Large B cell Lymphoma, it is the most common non Hodgekinlymphoma in the US
Explain diffuse large B cell lymphoma.
- Usually older adults, but 20% in children
- Lymphadenopathy and hepatosplenomegaly are observed.
- Some cases are associated with HHV8 and EBV, although Sketchy specifically said HIV can directly cause diffuse B cell lymphoma.
- In lymph nodes we see diffuse infiltrate of large, non cleaved lymphocytes.
- Alterations in BCL2 and BCL6
