I carefully considered the above objection when I first wrote my essay, but I decided against removing the cancer analogy. I though that making an analogy that would be remembered was important. For what it is worth, I myself am a cancer survivor and even after 10 years of it not coming back I still sweat bullets every year when I do my annual cancer screening.
If people stop worrying about forever offended people and someone announcing that they're offended becomes a headpat instead of attention then we will all be better off.