LAD Flashcards
Where B cells are located in the lymph node?
Outer cortex
Germinal follicles
Where macrophages and plasma cells are in a lymph node?
Medulla
Where T cells are in a lymph node?
Paracortex (between cortex and medulla)
3 histological patterns of reactive lymphadenopathy
Follicular hyperplasia– autoimmune, early HIV, toxoplasmosis
Paracortical hyperplasia– EBV, CMV, herpes, drugs
Sinus histiocytosis– draining tumors
Follicular lymphoma is generally indolent but 40% may transform to which aggressive lymphomas?
Diffuse large B-cell lymphoma
Burkitt lymphoma
How does immunophenotype contribute to diagnosing B-cell NHL?
Establish B-cell lineage
Small-sized lymphomas: CD5, CD10, CD23
High grade lymphomas
Burkitt lymphoma
Diffuse large B-cell lymphoma
Indolent
Small-sized cells
Mainly MALT sites (gastric, thyroid, lung)
Treatment: antibiotics, resection, radiation, chemo
Extranodal marginal zone lymphoma
Agressive
Large-sized cells
Extranodal and nodal disease
Treatment is aggressive chemo
Diffuse large B-cell lymphoma
Peidatric tumor
CD8+ T cell neoplasm
Characterized by ALK rearrangements, commonly t(2;5)
Agressive
Anaplastic large-cell lymphoma
Adult tumor
Mostly NK-cell neoplasm but may be T cell
Nasal mass with necrosis, extransive destruction and angioinvasion
Agressive
Extranodal NK/T-cell lymphoma
Nasal type
What are the clinical variants of Burkitt lymphoma?
Sporatic (ileocecal mass)
Endemic (EBV, breast, jaw, ovary mass)
Immunosuppression-related (EBV)
Transformation from follicular lymphoma
EBV-associated neoplasms
Lymphomas (mostly B): Endemic Burkitt, Post-transplant Lymphoproliferative disorder, Extranodal NK/T-cell lymphoma, nasal type; Subsets of Hodgkin lymphoma, diffuse large B-cell lymphoma, T-cell lymphomas
Nasopharyngeal carcinoma
What is interesting about classical HL?
It is a B-cell neoplasm but does not express CD20
