While it is highly likely that finasteride has caused epigenetic changes, that is not nearly as drastic as acute close proximity high radiation exposure, where your entire cellular structure is decomposed and chromosomes can literally be cut into pieces. As much as I love watching shows and reading about nuclear disasters… Even with my limited understanding of biochemical processes and medical knowledge I can tell you that the comparison is overly dramatic (if not a little absurd) and you really don’t need to worry about something like that.
From what I understand, an epigenetic change is more like a ‘state change’ and it’s still likely that this change can somehow be reverted.
But I don’t want to delve into theorizing any more than this.
The bottom line of my comment is that you shouldn’t worry so much as to concoct such fantastical horror scenarios, (even if they’re just metaphors). I understand this condition is awful and I’ve also had periods where things seemed only to be getting worse, but it’s likely that your situation can fluctuate and improve over time.
There’s no point in making it worse for yourself by giving yourself these ideas. You’re not melting.