Sentinel lymph nodes

Dr Elizabeth Baird (Remuera Dermatology) and Professor Rod Dunbar (University of Auckland) discuss sentinel lymph nodes and their role in melanoma treatment. A sentinel lymph node is the first lymph node or nodes, a cancer spreads to from the primary tumour.

Professor Dunbar refers to a procedure that identifies sentinel lymph nodes, which is called lymphoscintigraphy. The project to track the lymph nodes a melanoma drains to is the Melanoma spread pattern model by Dr Hayley Reynolds.

Note: This video contains graphic images of surgery.

Transcript

Dr Elizabeth Baird

Sentinel lymph node biopsy is a very common procedure that we perform for thick melanomas when we are concerned that they may have spread.

Professor Rod Dunbar

As part of therapy for melanoma, it's very common for patients to have the lymph nodes where melanoma has spread to removed. Obviously, for the sake of the patients, you would want to do that as soon as possible because the fewer cells that are there, the more likely you are to be cured and not have further therapy.  

Dr Elizabeth Baird

The problem is working out which lymph node that piece of skin is draining to. And in all our textbooks it says that, if you have a melanoma on the left arm, the lymph node that you will need to biopsy is in the left armpit. However, many studies have shown that that is not the case, and sometimes quite paradoxically, a lymph node on the right side might be the sentinel lymph node biopsy.

A technique that helps us work out the sentinel lymph node – i.e. the lymph node that that melanoma is draining to – is useful.

Professor Rod Dunbar

So in melanoma, it’s important to find out which lymph nodes would be the first ones that the melanoma cells would go to. At the Sydney Melanoma Unit, they have the most experience in the world in this – they have done over 5,000 cases. There is something very special that Hayley has been able to do in her project and that is to make a map across the three-dimensional surface of the human body to look at which lymph nodes are the first lymph nodes the melanoma cells would go to if they left the skin.

Dr Elizabeth Baird

A negative sentinel lymph node is great news for the patient and very, very reassuring. 

Acknowledgements:
Dr Elizabeth Baird, Remuera Dermatology
Professor Rod Dunbar, University of Auckland
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Dr Roger Uren