11.17: Hemo I Flashcards
What characterizes acute vs. chronic neoplasm?
Acute: Presence of immature cells (Blasts)
Chronic: Presence of differentiated, mature cells
***Subdivided into lymphoid or myeloid from here
What is leukemia?
- Malignant neoplasms of HSCs characterized by replacement of bone marrow by neoplastic cells
- These cells usually spill over into peripheral blood
What is a lymphoma?
- Proliferations arising from discreet tissue masses
* Lymph nodes, spleen, liver, etc.
What are the acute leukemias? What common clinical characteristics do they share?
- ALL and AML
- Both involve suppression of normal hematopoiesis by neoplastic blast cells
Lead to:
1. Anemia: Fatigue
2. Neutropenia: fever / infection
3. Thrombocytopenia: Bleeding
Clinical signs more prevalent in ALL than AML?
- CNS involvement
- Hepato / splenomegaly
- Lymphadenopathy
Who is ALL most common in?
- 80% of leukemias in children
- AML is more common in adults
Cells involved in ALL?
- Lymphoblasts: precursors of B and T lymphocytes
- 85% are B cell issues: mainly affects marrow with some spill over into blood as well
Presentation of T-ALL?
- Adolescents males
- Thymic mass in mediastinum
- Presents as lymphoma by moves to leukemic phase of blood and marrow
How is ALL diagnosed?
- Microscopic evaluation showing lymphoblasts with scant basophilic cytoplasm and fine nuclear chromatin
- **Hard to distinguish ALL from AML on microscopy
- Markers are used to distinguish if T or B cells are involved: TDT very important
- Chromosomal analysis is done as well
What is TDT?
“Terminal Deoxynucleotidyl Transferase”
- Marker that distinguishes acute (immature cell) from chronic (mature)
- This is present only in immature lymphoblasts
Prognosis for ALL?
- > 90% remission in children with 2/3 cured
- Best odds display the following:
1. 2 - 10 yo
2. Hyperdiploidy
3. TEL1-AML1 Translocation
What is the Philadelphia chromosome?
- BCR-ABL 9:22 translocation
- Poor prognosis in ALL
- First discovered in CML
Who is AML most often seen in?
- Adults
What is myelodysplastic syndrome?
"Preleukemia," "MSD" - Clonal stem cell disorder of defective hematopoiesis with increased risk of AML 2 types: 1. Primary / idiopathic 2. Therapy related
Characteristics of myelodysplastic syndrome?
- HYPERcellular marrow w/ peripheral cytopenia (ineffective hematopoiesis)
- Cells are being produced by not arriving to periphery - Clonal cytogenetic abnormalities:
- Stem cell gamage of some sort is background cause
- Morphologic abnormalities in all cell lineages
