Surely cancer has always been a threat, it's just that in more recent centuries or millennia humans have achieved long enough lifespans to actually see its effe

Surely cancer has always been a threat, it's just that in more recent centuries or millennia humans have achieved long enough lifespans to actually see its effects. Nowadays we live long enough to actually see the results of accumulated transcription errors as our cells regenerate (every 7 years I think?), which is basically the root cause of cancer. Things like carcinogens or radiation make those errors more likely and can cause fatal cancer to occur sooner, but even with otherwise perfect health and perfect bodies, my understanding is that we'd all die from cancer eventually (with a long life, but not that much longer than what we enjoy today).