Thread: Cancer

When you have Cancer Cell growth occurring at some point in your body, would it somehow also affect your lymph nodes? If it does, how, and Why? and also does it count for any type of cancer??

thank you
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In short, yes. It is possible for a cancer cell to break away from the original tumour mass, otherwise known as the primary tumour, and to gain access to the lymphatics system. It does this through a fairly complex process of localised invasion, followed by intravasation into lymphatic microvessels. The cancer cell can then be transported via the lymph system to distant sites. The cell may then leave the lymphatics system (extravasate) and form a micrometastasis. This may develop into a macrometastasis upon colonisation, so we have the formation of a potentially life-threatening secondary tumour (malignancy). In fact, it is estimated that ~90% cancer deaths are due to the spreading process (metastasis) and subsequent secondary tumours; it is not usually the primary tumour which kills people. The latter can be relatively easily removed surgically in most cases (depends on the tumour type). Hence, understanding the process of metastasis is really very important if we want to prevent cancer deaths.

As to *why* this happens, it can be put down to changes in the cancer cell at the molecular level which confer upon it the properties required for metastasis. Tumours are evolving beings, so if there is sufficient selection for such phenotypes, they will become more prevalent.

To address your final point, i *think* it does depend on cancer type. I.e. some cancer types have a higher probability of metastasising via the lymph system than others.

I refer you to pretty much the hero of the cancer biology field, Dr. Robert A. Weinberg. 'Biology of Cancer' (2007) Chapter 14 'Moving out: Invasion and Metastasis' p.587-653 8)

Heins, do you mean how are the lymph nodes affected in general or how does cancer get seeded in there?

As tridmity says, metastases can set up secondary tumors in the lymph nodes (and pretty much everywhere else). The lymph nodes produce a variety of soluble factors which are supposed to act as a sort of homing beacon for white blood cells. So if the metastases are expressing the right receptors, they'll home right to the lymph nodes just as lymphocytes would.

Putting aside metastases, your lymph nodes may also respond to the detection of cancer as they would to infection. Some lymphocytes function to eliminate new cancer cells on a regular basis (we get them all the time), so the lymph nodes may swell as they respond to cancer antigens by replicating rapidly before they migrate to the tumor site.