Large B cell Lymphomas Part II Flashcards
What is the key clinical history for
Plasmablastic Lymphoma?
- Male predominance
- occurs mostly in HIV
- also seen in post-transplant, autoimmune, and elderly
- can arise in extranodal sites
- mostly oral cavity
What is the morphology of
Plasmablastic Lymphoma?
- composed of large B cells with immunoblastic or plasmablastic morphology
What are the key IHC
findings for Plasmablastic Lymphoma?
- CD38, CD138 (+)
- IRF4/MUM1 (+)
- cytoplasmic Ig (+)
- EBV (+)
- Negative
- CD45
- CD20
How is Plasmablastic lymphoma differentiated
from Plasmacytoma and Primary Effusion Lymphoma?
- Plasmacytoma
- will be positive for CD56
- Plasmablastic lymphoma- negative
- Primary Effusion Lymphoma
- positive for HHV8
- Plasmablastic lymphoma- negative
What is the low-power morphology of
Plasmablastic lymphoma?
- starry sky
- diffuse growth without necrosis
- increased apoptosis and mitosis
- deep blue cytoplasm of cells
- absent dutcher or russell bodies
Note: EBV (+) excludes myeloma
* but if B cell markers are positive consider a DLBCL
What is a common genetic alteration
in Plasmablastic Lymphoma?
- MYC gene aberrations
- seen in 1/3 of cases
What are key things to know
regarding Intravascular Large B cell Lymphoma?
- symptoms are related to small vessel occlusion
- lymph node involvement is rare
- tumor often diagnosed on skin biopsies
What is the clinical presentation of
Primary Effusion Lymphoma?
- strongly associated with HHV-8, especially in AIDS patients
- Presents with:
- Effusions (pleural, pericardial, peritoneal)
- large atypical lymphocytes with immunoblastic, plasmablastic or anaplastic morphology
- cytoplasmic vacuolization
- Extracviatary PEL
- soft tissue or nodal mass
What is the immunohistochemical profile of
Primary Effusion Lymphoma?
- Positive:
- CD45, CD30, CD38, CD138 and EMA
- HHV8, EBV, and MUM1
- Negative:
- for B and T cell markers and myeloid markers
What is the clinical presentation of
Primary Cutaneous DLBCL, leg type?
- affects predominantly elderly women
- 90% of cases on lower extremity
- but can be anywhere
What are the morphological findings
of primary cutaneous DLBCL, leg type?
- nonepidermotropic, deep seated
- large B cells, nodules of tumor in dermis
- positive for pan B cell markers
- BCL2 and BCL6 positive
- MUM1 +
- CD10 negative
Note: BCL2 will be negative in Primary cutaneous FL
What is the clinical for Lymphomatoid granulomatosis?
- it is an angiocentric, destructive, large B cell lymphoma
- commonly affects lungs
- may involve upper aerodigestive tract, brain, kidneys, and liver
- IMP: must have lung involvement if there are other foci
What is the morphology and IHC of
Lymphomatoid granulomatosis?
- neoplastic cells infiltrating into vessel walls, can look like a vasculitis
- large number of reactive T cells
- plasma cells and histiocytes
- associated with EBV infection and immunodeficiency
- IHC:
- large B cells are EBV
- CD20 +
What is the grading for
Lymphomatoid Granulomatosis?
- Based on EBV positive cells / HPF
- Grade 1: < 5
- Grade 2: 5-20
- Grade 3: > 20
What are the key clinical findings
of DLBCL associated with
chronic inflammation?
- B cell lymphoma that arises at sites of longstanding inflammation
- prototype is lymphoma arising within a longstanding pyothorax
- neoplastic cells express EBV
What is the key clinical presentation
for EBV + DLBCL, NOS?
- affects extranodal sites of elderly adults in Asian populations
- neoplasm is thought to be related to immune system senesence
- no immune deficiency or piror history of lymphoma
- IHC:
- CD10 and BCL6 are negative
- MUM1 and EBV are positive
What are the EBV + large
B cell neoplasms?
- Plasmablastic lymphoma
- Primary effusion lymphoma
- Lymphomatoid granulomatosis
- DLBCL associated with chronic inflammation
- EBV+ DLBCL, NOS
- EBV + mucocutaneous ulcer
- Hodgkin like features
- indolent course
What are the most common lymphomas
in HIV infection?
- Burkitt lymphoma
- DLBCL
- especially of the CNS
- PEL
- Plasmablastic lymphoma
- Hodgkin Lymphoma
What is the key clinical association/features
in PTLD?
- abnormal lymphoid proliferation following transplantation
- usually within the first year
- EBV has been implicated in most cases
- seen in early cases
- EBV (-) are seen later in the course
- usually > 5 years, more aggressive
- Elevated EBV-DNA viral load is predictive of an emerging PTLD
Who is at risk for developing
PTLD?
- Heart-lung, liver-bowel reciepients, highest
- renal and BM, lowest incidence
- children are most at risk
- EBV negative recipient at time of transplant, high risk
- Most immunosuppressed, highest risk
What is true of most PTLD origins ?
- most PTLDs are clones of recipient origin
- < 10% are of donor origin
- PTLD often involves the allograft itself
- spectrum of proliferations
- reactive plasmacytosis all the way to monomorphous PTLD
- majority of those are high grade B cell lymphomas
- reactive plasmacytosis all the way to monomorphous PTLD
What is the morphology of Burkitt Lymphoma?
- diffuse proliferation of intermediate cells
- rim of basophilic cytoplasm
- round nuclei with multiple nucleoli
- tingible body macrophages impart Starry sky appearance
What is the immunophenotype of
Burkitt Lymphoma?
- Positive
- CD19, CD20, CD22
- CD10, BCL6
- MYC, ki67 99%
- surface Ig
- Negative
- BCL2
- CD5, CD23
- Tdt, CD34
What are the key genetics of Burkitt
Lymphoma?
- positive for MYC gene rearrangement
- MYC/IGH fusion
- t(8;14)
- also MYC can rearrange with the light chains
- IgK (2p12)
- IgL (22q11)
What is Burkitt-like lymphoma with 11q aberration?
- resembles Burkitt lymphoma
- lacks the MYC gene rearrangement
- shows a chromosome 11q alteration
- clinical course similar to Burkitt lymphoma
