Not to diminish the severity of the medical issue the OP faces, but this situation reminds me of the old joke:
A man walks into a bar with a toad on his head. the bartender looks at him and says " hey buddy, what the hell is that". before anyone else can speak the toad quietly says " I've got no idea, it just started out as a pimple on my ass"
Moral of the story. Get it dealt with.
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