Diagnostic cytology Lecture 2 Flashcards
What are the best lymph nodes to sample?
Popliteal and prescapular nodes - submandibular have higher exposure to antigenic stimulation
What are the five different types of lymph node findings that can be seen?
- Normal findings
- Hyperplastic/reactive change
- Inflammation/necrosis
- Lymphoma
- Non-lymphoid (metastatic) neoplasia
What are the findings that will be observed in a “normal” lymph node?
- Normal lymph nodes - 75-85% well-differentiated lymphocytes - 1 to 1.5 times size of erythrocytes
- 5-10% intermediate (medium) lymphocytes - 1.5 to 3 times size of RBC
What is your diagnosis for a lymph node with this appearance?
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Normal lymph node
Name the lymph node finding shown below:
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Lymphoblast
Name the lymph node finding that is shown below:
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Plasma cell
Name the lymph node finding that is shown below:
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Macrophage
How big are lymphoblasts in comparison to an erythrocyte?
Lymphoblasts are generally 2 to 4 times the size of an erythrocyte and are larger than a neutrophil
Name the finding that is shown below:
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Lymphoblasts - generally 2 to 4 times the size of an erythrocyte
In what ratios should plasma cells, macrophages, neutrophils, eosinophils and mast cells be found in normal lymph nodes?
- Plasma cells (<3%)
- Macrophages (occasional)
- Neutrophils (<1%)
- Eosinophils (<1%)
- Mast cells (<1%)
What finding will be seen in reactive lymph nodes?
- Intermediate and large lymhocytes - increased number up to 15-20%
- Plasma cells vary from none to 5-10%
- Macropahges greater than 2%
What cells are shown in the red arrows below?
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Increased plasma cells in the mesenteric lymph nodes
What cell type is shown below (red arrows)?
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The cell type shown are lymphoblasts
What are the two different ways that lymphadenitis can arise?
Lymphadenitis is inflammation of the lymph node and may be:
- Primary = node itself is inflammed or necrotic
- Secondary = node is draining an area of inflammation/necrosis
What term describes a lymph node with neutrophils >5%?
Purulent lymphadenitis
What term describes a lymph node with eosinophils >3%?
Eosinophillic lymphadenitis
What term describes a lymph node where macrophages are predominant?
Histiocytic
What term describes a lymph node where neutrophils and epithelioid macrophages are predominant?
Pyogranulomatous lymphadenitis - Mixture of neutrophils + epithelioid macrophages - due to systemic fungal infections (e.g. cryptococcis)
What characteristics on a smear lead to a suspected diagnosis of lymphoma?
- Immature cells > 50%
- Frequently medium and large lymphocytes exceed 80%
- Small cell lymhoma is difficult to diagnose - predominance of small, well differentiated lymphocytes