How do you die from skin cancer? Or, how does skin cancer kill you?
By spreading all around your body. If you’re thinking of Maureen Reagan, for instance, what started as skin cancer had spread to her spine and brain.
When cancer cells break away from a malignant tumor and enter the lymphatic system (the dermis is rich with lymphatic vessels), they have quick & easy access to other organs like the lungs & brain. But in stead of calling it brain cancer, I think the term is metastatic melanoma.
A cancer that has metastasized is usually referred to by the way it began. So, for example, actor Michael Conrad (who played Sgt. Phil Esterhaus on Hill Street Blues) was said to have died of “urethral cancer” even though, obviously, the loss of one’s urethra by itself couldn’t kill anyone.
My urologist ex-girlfriend explained to me that this is a sensible way to classify cancers, because cancers that start in different parts of the body can behave differently, but tend to behave in the same way even when they’ve metastasized.
I didn’t explain that very well. Let’s look at it like this: Lance Armstrong’s testicular cancer spread to his brain, but once in his brain it still acted like testicular cancer, not like a brain tumor that began in the brain.
I’ll shut up now because I’m sure there’s an oncologist out there who can describe this better.
Or another way of looking at it: When the mutant, cancerous cells metastasize, they don’t infect the new host tissue and cause the local cells to become cancerous. It’s the original cancerous cells that have taken root and continue the spread.
So, in the recent case of Maureen Reagan’s melanoma (a cancer of the pigmentation cells) the mutant pigmentation cells did the traveling, took up residence in her brain, spine, and probably everywhere else, and continued growing. It didn’t cause the local brain, spine, etc. cells to become cancerous.