I don’t know of any contagious human cancers but I know that there is a contagious cancers that dogs can get and a different contagious cancer that Tasmanian Devils can get.
Perhaps one of the others will know about in people?
I didn’t think so, so Emma’s answer was interesting to me. You can certainly put a bit human tumour into mice and make them grow tumours. But you can’ get somebody’s tumour by day-to-day contact, such as through sneezing.
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