Hematology Week 3: Lymphoma II Flashcards
Lymphoma Main Categories
Follicular Lymphoma Clinical Features
4 listed
- Painless generalized lymphadenopathy is common
- incurable and indolent clinical course except when transformed
- histologic transformation occurs in up to half of the cases
- Diffuse large B-cell lymphoma is the most common type of transformation but can also become Hodgkins Lymphoma
Most common indolent type of Non-Hodgkin Lymphoma in the US
Follicular Lymphoma
Follicular Lymphoma Morphological Features
5 listed
- Nodular growth pattern
- closely arranged neoplastic follicles
- Neoplastic cells include:
- Small cleaved lymphocytes (centrocytes)
- Large lymphocytes (centroblasts)
Follicular Lymphoma Cells arise from?
Germinal Center B-cells
Follicular Lymphoma Neoplastic Cells
2 listed
- Small cleaved lymphocytes (Centrocytes)
- Large Lymphocytes (Centroblasts)
Follicular Lymphoma Histology
look like germinal center cells
Neoplastic vs Reactive Follicles: Reactive Follicle Features
4 listed
- Reactive Follicle:
- Intact mantle zone
- Many ‘tingible body’ macrophage
- polarization is present
Neoplastic vs Reactive Follicles: Neoplastic Follicle Features
3 listed
- Absent or thin Mantle Zone
- Lack of ‘tingible body’ macrophages
- lack of polarization
Identify
Reactive Follicle
Tingible Body Macrophages
beig macrophages with lots of debris
present in a reactive follicle
Absent in neoplastic follicle
Follicular Lympha Flow Cytometry
- Small cells
- CD19+ CD20+ and CD10+ (germinal center like)
- Monoclonal so either kappa or lambda
Follicular Hyperplasia Flow Cytometry
- small cells
- few CD10+ germinal center cells
- B cells are not monoclonal
Follicular Lymphoma Genetics
t(14;18)(q32;q21)
- present in 90% of follicular lymphomas
- Balanced reciprocal translocation
- BCL2 oncogene on chromosome 18 is juxtaposed to IGH gene on chromosome 14
- Results in upregulation of BCL2 gene
Follicular Lymphoma specific mutation
Follicular Lymphoma Genetic testing
t(14;18)(q32;q21) can be seen in karyotype
or FISH
Follicular Lymphoma Pathophysiology
3 listed
consequences of BCL2/IGH rearrangement
Follicular Lymphoma Immunohistiochemistry
- Reactive follicles never express BCL2
- Only neoplastic germinal centers express BCL2 in 90% of them
Mantle Cell Lymphoma prevalence
2.5% of Non-Hodgkin Lymhoma
Mantle Cell Lymphoma Clinical Presentations
- commonly present with painless lymphadenopathy
- Frequent extranodal involvement including BM, spleen, liver and GI tract
- intestinal involvement may present with polyps (lymphomatoid polyposis)
Mantle Cell Lymphoma Prognosis
4 listed
- Very aggressive
- Poor prognosis
- median survival 3-4 years
- Currently incurable
Mantle Cell Lymphoma Cells come from?
Mantle Cell Lymphoma Morphologic Features