Week 2- approach to the investigation of lymphadenopathy

Question 1

What can cause lymphadenopathy?

Answer 1

Viral- e.g. EBV
Bacterial
Lymphoma
Malignancy- particularly metastatic spread. 
Connective tissue disorders e.g. SLE.

Question 2

Put the list of differential diagnosis for lymphadenopathy in order from most likely to least likely?

Answer 2

Reactive
Bacterial infection (local)
Viral infection (generalised)
Metastatic malignancy
Lymphoma

Question 3

What causes tender lymphadenopathy?

Answer 3

Viral and bacterial causes.

Question 4

What causes hard lymph nodes?

Answer 4

Viral, bacterial and metastatic carcinoma

Question 5

What causes rubbery lymph nodes?

Answer 5

Lymphoma

Question 6

What causes the surface of the lymph node to be smooth/

Answer 6

Viral, bacterial and lymphoma.

Question 7

When would the skin become inflamed in lymphadenopathy?

Answer 7

In a bacterial infection

Question 8

When would the skin be tethered in lymphadenopathy?

Answer 8

Could be tethered in bacterial infection but also likely to be metastatic carcinoma.

Question 9

What should you do if lymphoma or other malignancies are suspected?

Answer 9

Ask surgeon to biopsy.

Question 10

How do you assess lymph node pathology?

Answer 10

Histology- microscopic appearance
Immunohistochemistry solid node
Immunophenotyping blood/marrow
Genetic analysis
Molecular analysis

Question 11

What is immunohistochemistry used for?

Answer 11

Confirming its a lymphoma and classifying it.

Question 12

What does immunohistochemistry do?

Answer 12

Looks at patterns of proteins on the surface of lymphoma cells. Uses antibodies against these to look for reactions. If it turns brown then it is positive.

Question 13

What is CD20 found in?

Answer 13

Non-Hodgkins lymphoma

B cell lymphomas

Question 14

What is CD30 found in?

Answer 14

Hodgkins disease.

Question 15

Describe the process of immunophenotyping?

Answer 15

Cells are tagged with antibodies attached to a fluorochrome molecule. It emits a certain colour when a laser is shone on it if it binds to an antigen.

Question 16

When is immunophenotyping useful?

Answer 16

Useful in leukaemias and in lymphomas involving bone marrow.

Question 17

What does cytogenetic analysis look for?

Answer 17

Specific patterns of chromosome abnormalities.
G banding- aspirate the node and grow cells in culture and look at the spread of chromosomes.
FISH-look for specific abnormalities in chromosomes using probes that emit a specific light colour.

Question 18

If you’ve got a lymphoma, what is the first question?

Answer 18

Whether it is Hodgkins or non-hodgkins lymphoma

Question 19

If its non-hodgkins lymphoma, whats the next question needing answering?

Answer 19

Is it T cell (10%) or B cell non Hodgkins lymphoma (90%).

Question 20

How can B cell non-hodgkin lymphomas be further divided?

Answer 20

Into low grade and high grade non-Hodgkin lymphomas. If low grade- it grows slowly and can be treated with chemo but can’t be cured. If high grade responds well to chemo and can be cured.