Anatomy and Cancer Flashcards
Define desmoplasia.
A growth of excessive supporting stroma surrounding a tumour.
Define anaplasia.
List 6 characteristics of anaplastic tumours.
- Anaplasia is a condition of cells with poor differentiation.
1 - Hyperchromatic nuclei.
2 - Abundant mitosis.
3 - Loss of polarity.
4 - Presence of tumour giant cells.
5 - Ischaemic necrosis.
6 - Pleomorphism.
Define tumour giant cell.
A cell in which mitosis occurs so rapidly that multiple nuclei can be found within one cell, and there is an excessively large volume of cytoplasm (as the cell has reproduced nuclei faster than it has been able to split).
Why might malignant tumours undergo ischaemic necrosis?
Malignant tumours might undergo ischaemic necrosis as the cancer cells are dividing faster than the blood supply is able to catch up.
Define pleomorphism.
- Pleomorphism is high variation in the size and shape of the cells and nuclei within a population of cancer cells.
- This is characteristic of malignant tumours.
Define dysplasia.
Dysplasia is loss of cellular uniformity, which is reversible if the inciting stimulus is removed.
Define metaplasia.
Metaplasia is the transformation of one differentiated cell to another.
How does growth rate of a tumour affect differentiation?
- Growth rate inversely correlates with the level of differentiation:
- If a tumour is slow-growing, it has more time to undergo differentiation, therefore slow-growing tumours are more poorly differentiated.
- If a tumour is fast-growing, it has less time to undergo differentiation, therefore fast-growing tumours are less poorly differentiated.
List 3 mechanisms of cancer spread.
1 - Local spread (invading into surrounding structures).
2 - Lymphatic spread (via lymph vessels / nodes).
3 - Haematogenous spread (via venous drainage).
Describe the organisation of the lymphatic system.
https://drive.google.com/file/d/1I56J1sCTxFYtMkOrlYBYiTQVKXxqQRIE/view?usp=sharing
What is the cisterna chyli?
The cisterna chyli is a lymphatic channel that receives lymph from the lower limbs, lumbar trunks and intestinal trunk, and empties into the thoracic duct.
From which trunks does the thoracic duct receive lymph?
The thoracic duct receives lymph from the:
1 - Intercostal trunks.
2 - Mediastinal trunks.
3 - Left subclavian trunks.
4 - Jugular trunks.
From which trunks does the right thoracic duct receive lymph?
The right thoracic duct receives lymph from the:
1 - Right subclavian trunks.
2 - Jugular trunks.
What is a sentinel lymph node?
Why is it important clinically?
- A sentinel lymph node is the first lymph node that drains a tumour.
- It is used to predict the likelihood of tumour spread (staging). If no cancer cells are found within it, unnecessary lymph node removal can be avoided.
- The sentinel lymph node can also be removed to prevent lymphatic spread (but you might end up with oedema!).
How is the sentinel lymph node of a tumour identified?
- A dye is injected at the tumour site.
- The first lymph node that the dye drains to is the sentinel lymph node.