This article says nothing about how lifespans are far longer now, as the comments section points out. Cancer is what you die of when everything else fails to kill you. Cancer is only "purely man-made" in the same sense that increased life expectancy is "man-made" too.
Where would this go on the list of various things this famously ridiculous newspaper has reported either cause or cure cancer (or mysteriously do both)?
Melanomas are the result of industrialisation right? I can certainly accept cancer might be more common now due to various factors, but 'purely man made' is hyperbolic.