I have found it to be worse because my brain had nothing else to do but spin itself into a frenzy. Everything took me back into one trauma or another.
It sounds like I absolutely lucked out in that all of my doctors formed one giant round robin in caring for me, so they all knew about my rampaging PTSD, and that I'd also unexpectedly lost my mother just three months prior to the cancer discovery, which when combined added a new PTSD causation to my diagnosis. For all their gentleness, though, it certainly didn't stop me cycling when I dropped into reality between med doses during recovery.