Lymphadenopathy and EBV Flashcards
What is the transit for B cells?
Bone marrow (maturation)
Blood
Enter lymph node through High Endothelial Venule
Migrate to cortex
Begin in mantle zone as naive B cells
Clonal expansion in germinal center in response to antigen
Migrate to marginal zone and differentiate into plasma cells
Exit via efferent lymphatics
What is the transit for T cells?
Thymus (maturation)
Blood
Enter lymph node through High endothelial venules (HEV)
Migrate to paracortex
Clonal expansion in response to antigen
Exit via efferent lymphatics
What are causes of Reactive Lymphadenopathy (also is reactive more likely in children or adults)
Histologic patterns?
(Reactive lymphadenopathy is more common in children)
Infectious: Infectious mononucleosis/cat scratch/others
Autoimmune
Follicular hyperplasia: B cell expansios
Paracortical hyperplasia: T cell expansions
Sinus histiocytosis
What are examples of non Hodgkin lymphomas (neoplasms of mature B cells)
Burkitt lymphoma
Diffuse large B-cell lymphoma
Extranodal marginal zone lymphoma
Follicular lymphoma
Mantle cell lymphoma
What are examples of Neoplasms of mature T cells or NK cellS?
Peripheral T-cell lymphoma unspecified
Anaplastic large-cell lymphoma
Extranodal NK/T cell lymphoma
What are types of Hodgkin lymphomas?
Classical Hodgkin lymphoma
Nodular lymphocyte predominate Hodgkin lymphoma
Important parameters for reactive vs. neoplastic lymphadenopathies in clinical exam
Duration/growth interval?
Size (<1cm is better)?
Location (if location in area that typically does not drain, then bad)? Extent?
Tender (reactive associated) vs. Nontender (neoplastic associated)?
**Fixed **vs. mobile (reactive associated)?
Associated physical exam findings?
Causes for reactive lymphadenopathy?
Infectious
Autoimmune
Drugs
Foreign body
Castleman’s disease
Sarcoidosis
Kikuchi-Fujimoto
Kimura’s disease
Rosai dorfmann
Causes for Neoplastic lymphadenopathy
Lymphoma
Leukemic involvement (lymphoblastic lymphoma/myeloid sarcoma)
Metastatic tumor
What are the reactive lymphandenopathy histologic patterns?
Follicular hyperplasia- Autoimmune/early HIV/Toxoplasmosis
Paracortical hyperplasia- EBV, CMV, Herpes, drugs
Sinus histiocytosis- Draining tumors
Necrotizing- Cat scratch/bacterial/fungal/autoimmune/viral
Granulomatous-fungal, tb
Mixed
JUST KNOW THE BOLDED FIRST THREE
What is rituximab and what is it used for?
Mech of action?
Humanized murine IgG antibody targeting Cd20 antigen. Used to treat Follicular Lymphoma and appears to improve survival
MOA: CDC/ADCC/Apoptosis/ionizing radiation induced cell death
Burkitt Lymphoma
CDs?
Genotype?
How does it present?
CD10+/CD19+/CD20+
c-MYC and immunoglobulin loci: t(8;14) t(2;8) t(8;22)
Adolescent or young adults with rapidly growing extranodal masses (ileocecum); uncommonly presents as leukemia
Aggressive
3 variants:
endemic (EBV associated)
sporatic
Immunosuppression-related (EBV-associated)
Diffuse Large B-Cell Lymphoma
CDs?
How does it present?
CD 19+/CD20+
All ages but commonly adults. Rapidly growing mass/lymphadenopathy
Aggressive
Extranodal marginal zone lymphoma (MALToma)
CDs?
Genotype?
Features?
CD 5-/CD10-/CD19+/CD20+
t(11;18) most common creating MALT1-IAP2 fusion
Localized, associated with chronic infections or inflammatory diseases (H. pylori) or (Hashimoto’s thyroiditis). Indolent. Arises in the lymphoid tissue of mucosal/epithelial-based sites in adults.
Indolent.
Follicular lymphoma
CDs?
Genotype?
Manifestation?
CD 5-/CD10+/CD19+/CD20+
t(14;18) BCL2-IgH fusion gene
Adults with generalized lymphadenopathy, frequent retroperitoneal involvement. Slow growth but 40% transofrm to more aggressive lymphoma (Burkitt lymphoma or Diffuse Large B-cell lymphoma)
Mantle cell lymphoma
CDs?
Genotype?
Manifestation?
CD 5+/CD10-/CD19+/CD20+
t(11;14) CyclinD1 overexpression
Older males with disseminated disease, frequent GI involvement; moderately aggressive
Peripheral T-cell lymphoma, unspecified
Cell of origin?
Features?
Helper T cell
Older adults, presents with lymphadenopathy, aggressive
Anaplastic Large-cell lymphoma
Cell of origin?
Genotype?
Clinical features?
Cytotoxic T cell
Rearrangement of ALK gene
Children, with lymph node and soft tissue disease. Aggressive
Extranodal NK/T-cell
Cell of origin?
Genotype?
Features?
NK-cell commonly or cytotoxic t cell rarely
EBV assoc
Adults with destructive extranodal masses, commonly sinonasal. Aggressive
Classical Hodgkin Lymphoma
What age present?
Site of involvement?
Characteristics?
CDs?
Cell of origin?
What type is most common and that we need to know and how does it characteristically present?
Adolescents
Mediastinum, cervical
Characterized by Reed Sternberg cells (large eosinophilic nucleoli (owl eye) Large size with frequent binucleation. Contiguous spread, lymph node involvement
CD 15+/CD30+/CD20-/CD45-
B cell lineage (despite not expressing CD20)
Nodular Sclerosis Hodgkin Lymphoma most common presenting with mediastinal mass
Nodular lymphocyte predominate Hodgkin lymphoma
Nodular collections of popcorn cells admixed with lymphocyte
CD15-/CD30-/CD20+/CD45+
B cell origin
INdolent with frequent relapses
