L15 - Cancer causes to cures

Question 1

What are lymphatic capillaries?

Answer 1

They are blind ending tubes made of endothelial cells. They contain valves and are 15-75um in diameter

Question 2

What drains into the cysterna chyli?

Answer 2

Lymph from the lower limbs, interstines and the right and left trunk.

Question 3

What lymph drainage combines with that of the cysterna chyli and where does it go?

Answer 3

Eventually drains to the thoracic duct which drains into the left subclavian vein. The lymph from the cysterna chyli is joined by the intercostals, left bronchomediastinal, left subclavian and left jugular.

Question 4

What is the lymph drainage that does not drain into the thoracic duct?

Answer 4

The right jugular trunk, right subclavian and right bronchomediastinal nodes. These drain into the right lymphatic duct which drains into the right subclavian vein.

Question 5

What percentage of the blood volume becomes lymph?

Answer 5

Roughly 10%

Question 6

What is chyle?

Answer 6

It is the lymph drainage from the GI system that is especially fatty.

Question 7

What are the four main mechanisms of cancer spread?

Answer 7

Direct extension (seeding)-local spread to adjacent tissues
Lymphatic spread-predictable
Haematogenous spread - veins especially
Metastatic cascade

Question 8

what is the main problem with primary local tumour spread?

Answer 8

If the tumour is in a small space then it can compress other structures.

Question 9

what is lymphatic secondary spread?

Answer 9

The most common form of spread which is the most predictable.

Question 10

How much lymph is produced a day?

Answer 10

Up to 3L

Question 11

What is the advantage of lymph plexuses having no basement membrane to their endothelium?

Answer 11

It means that surplus tissue and even whole cells can enter them to be drained from the interstitual space.

Question 12

What is the path of superficial and deep lympathic vessels?

Answer 12

The superficial lymphatic vessels are more numerous than veins and anastomose freely, they then drain into the deep lymphatic vessels.
Deep lymphatics accompany arteries and also drain internal organs.

Question 13

What is the result of ligation of lymphatic trunks or even the thoracic duct itself?

Answer 13

Usually only has a transient effect due to new patterns of drainage being esablished through lymph-venous communications elsewhere in the system.

Question 14

Where is a common site of secondary cancer sites?

Answer 14

The lymph nodes where cancerous cells are trapped as they try to spread through the lymph system.

Question 15

How would a cancerous lymph node present?

Answer 15

Swollen but unpainful upon pressing

Question 16

Which type of cancer most commonly spreads by Haematogenous spread?

Answer 16

Sarcomas (connective tissue cancers). Occurs more often by venous routes than arterial routes as veins have thinner walls so are easier to penetrate.

Question 17

What are the most common secondary sites for haematogenous spread of cancer?

Answer 17

Liver and lungs as this is where the venous blood tends to flow to.