Approach to lymphadenopathy and diagnosing lymphoma Flashcards
what are differential diagnoses for a ‘lump’ / lymphadenopathy
lymphoma
infections - ‘reactive’
malignancy - metastatic
connective tissue diseases eg SLE
what should you assess for when examining lymph nodes clinically
regional vs generalised
tender vs non-tender
consistency and surface
skin inflammation elsewhere
describe lymph node findings in a viral infection
tender, hard, smooth nodes
no skin inflammation or tethering
describe lymph node findings in a bacterial infection
tender, hard, smooth nodes
possible skin inflammation and tethering
describe lymph node findings in lymphoma
non-tender, rubbery/soft, smooth nodes
describe lymph node findings in metastatic carcinoma
non-tender, hard, irregular nodes
tethered
carcinomas/sarcomas spread through lymphatics
carcinomas spread through lymphatics
sarcomas spread haematogenously
FNA and core biopsy are acceptable methods to sample suspicious lymph nodes, true or false
FALSE
need a big sample
lymphoma can be diagnosed by CT scan, true or false
FALSE
what are the 5 steps to assessing lymph node pathology
Histology Immunochemistry Immunophenotype Cytogenetic analysis Molecular analysis
what is immunohistochemistry
identifies antigens on cell surfaces using specific antibodies
identifies CD numbers
confirms and classifies lymphoma
what is a CD number
Cluster of Designation eg CD30+….
what is immunophenotyping and how does it differ from immunohistochemistry
differs as it uses cells in a liquid phase
cell surface antigens are identified by fluorescently tagged antibodies
flow cytometry assesses this
determines CD number
very useful in leukaemias and lymphomas involving marrow
what is cytogenetic analysis
identifies certain patterns of chromosomal abnormalities in certain lymphomas
grow cells in culture and look at chromosomes
FISH technique
what is molecular analysis
assesses patterns of gene expression
helps to classify lymphoma
