Lymph Node Cytology

Question 1

Why/ when would we sample a lymph node? (3)

Answer 1

• If patient has Lymphadenomegaly (enlarged lymph nodes)
• To evaluate the extent of Metastasis
• To classify a lymphoma

Question 2

Why would we prefer to aspirate a lymph node rather than biopsy it?
BUT when is a biopsy indictated and why?

Answer 2

Less invasive, cheaper and does not need general anaesthesia
Biopsy indicated to view metastasis and grade lymphoma as need to view cell detail and architecture

Question 3

What are the 5 lymph node classifications?

Answer 3

Normal
Hyperplastic/ Reactive
Lymphadenitis (inflammation)
Lymphoid neoplasia
Non lymphoid neoplasia

Question 4

A lymph node that is enlarged but has a normal cell types is a…

Answer 4

hyperplastic lymph node

Question 5

What is characteristic of the cells in a Hyperplastic/ reactive lymph node?

Answer 5

Increased % of medium to large lymphocytes BUT still less than 50% of cells

Question 6

What is characteristic of the cells in Lymphadenitis?

Answer 6

Increased percentage of inflammatory cells such as Neutrophils, Eosinophils, Macrophages
[Can characterise the lymphadenitis based on which inflammatory cell type if most prominent]

Question 7

Lymphoid neoplasia contains predominantly what cell types?

Answer 7

Immature lymphocytes (med-large) - monotonous (all the same)

Question 8

Clusters of epithelial cells on a lymph node sample suggests…

Answer 8

Metastatic neoplasia (because they’re foreign cells)

Question 9

We know T and B cells are unrecognisable under cytology so how can we differentiate a T cell and a B cell lymphoma? (2)

Answer 9

We can use PCR clonality detection of T and B cells
OR Flowcytometry (uses immunophenotyping)