5 categories of lymphadenopathy
- Normal
- Hyperplastic (reactive)
- Lymphadenitis (inflammatory)
- Lymphoma
- Metastasis to LN
T/F - submandibular LNs are preffered for FNAs
False - they are usually reactive (constantly draining)
Perform lymph panel instead
Which cells should you find in a normal LN
MIXED CELL POPULATION
- Small mature: 90%
- Medium sized/prolymphocytes: 5%
- Lymphoblasts: 2%
- A few mast cells, eosinophils etc
Is this a healthy LN? Why?
Yes - mixed cell population
- Small, mature lymphocytes
- Medium sized lymphocytes (prolymphocytes)
- Etc
A LN with an increasing number of prolymphocytes and plasma cells is…
Reactive
(small mature lymphoctyes still dominate)
What’s this?
Mott cell
- Activated plasma cell
- Dots are where immunoglobulins were —> dissolved due to staining
Whats a lymphoglandular body? Do these indicate a LN is abnormal
Pockets of cytoplasm that pinch of lymphoctyes, forming independent structure
Dont necessarily indicate LN abnormal —> more common in LN pathology
Is this LN normal? Why?
No- reactive
- Increased prolymphocytes
- Increased plasma cells
- Lymphoglandular bodies
A LN is infilitrated with non-degenerate neutrophils. What is this condition called?
Sterile lymphadenitis
Causes of reactive/hyperplastic LN
Drainage of infected site
- LN is healthy —> not inflammed, not infected, not neoplastic!
A LN has many degenerate neutrophils and some intracellular organisms. What is the condition?
Septic lymphadenitis
What is granulomatous lymphadenitis
Influx to LN of:
- Mycobacteria
- Fungi
- Protozoa (toxoplasma)
- Foreign body
Is this a normal LN?
No - influx of neutrophils. Lymphadenitis
Septic (degenerative)?
A lymph node has >50% of cells that are lymphoblasts or prolymphocytes. What do you suspect
Lymphoma –> diagnostic if over 50%
(suspected at >30%)
Staging of lymphma (5)
- Single LN
- Multiple regional LN
- Generalized lymphadenopathy
- (stage 3) + liver and spleen
- Involves bone marrow
Lymphoma originates in….
Leukemia originates in…
Lymphoma: LN
Leukemia: bone marrow
Is this a healthy LN?
No - homogenous, immature cell population
Lymphoma
Tests used to subtype lymphoma
- Behaviour: responsiveness to chemo (B-cells respond, T-cells dont)
- Flow cytometry - CD proteins
- T-cells: CD3
- B-cells: CD79a
- PARR - PCR for antigen receptor rearrangements
- Karyotyping (abnormal chromatin patterns)
Is this a normal LN?
No - this shows epithelial cells in LN. Indicates metastasis to LN
