Lymphadenopathy and Malignant Lymphoma Flashcards
Lymphadenopathy, what it is due to
Enlargement of lymph nodes
Could be reactive or neoplastic
Lymphadenitis - LAD due to inflammation
How do you describe LAD?
Location Size Number Firm vs. soft Mobile vs. fixed Painful vs. non
Lymphadenopathy and pain
Painful usually due to infection
Painless due to chronic infection, tumors, or lymphoma
Malignant lymphoma
Clonal proliferation of lymphocytes in lymphoid tissue
Genes leading to lymphoma
BCL6 - maturation
MYC - proliferation
BCL2 - survival
How do you evaluate someone with LAD?
History
Exam
Imaging
Pathology
PET scan
Demonstrates which tissues are more metabolically active
Types of pathological sampling
Fine needle aspiration - not enough to make diagnosis
Core needle biopsy - better
Excision biopsy - best
Can also do bone marrow biopsy/aspirate or CSF
Why are lymphocytes prone to mutations
VDJ recombination
Somatic hypermutation
Class switch recombination
What part of lymph node has most mutations
Germinal center
Clinical manifestation of malignant lymphoma
LAD Extra-nodal involvement Visceral involvement Organ dysfunction Immune dysfunction B symptoms
Etiologies of malignant lymphoma
Environment Infectious Immune defect/immune stimulation Hereditary Multifactorial
Polyclonal vs monoclonal
Reactive T or B cell are polyclonal
Neoplastic are monoclonal
Can asses by assessing Ig of TCR gene rearrangements…restricted expression of kappa or lambda chain serves as a surrogate for monoclonality
Diagnosis of malignant lymphoma
Histology
Immunophenotype - flow cytometry
Cytogenic abnormalities
Burkett lymphoma mutation
t(8,14) - C-MYC…up regulates proliferation
