I bought no-nose saddles for both my bikes when I started radiotherapy. Actually, we were told not to ride out bikes, which my onco thought was OTT. I had already ordered the no-nose saddle at that point, showed it to the radiotherapists, and they said, That should be fine.
No-nose is rather misleading in terms of the feature I was after - no perineum would be a better description, so you are sitting on your pelvis bone, and there's nothing under the perineum.
This is the one I got:
It took about 3 rides to get used to them and get them adjusted comfortably. I don't need them anymore, but I've kept them on the bikes and now find them comfortable. I have recommended them to a few people, and at least one of them said it was dire and gave up. I don't think he put in any time to get used to it or adjust it though.
Without the nose, there's not much to prevent it slipping out sideways if you're mountain biking, but you quickly get used to using your arm and leg muscles to perform that function.