According to AI neither is a “safe” just different side effects sometimes depending on a specific case ADT, chemo and radiation is used, think of chemo as carpet bombing, and Radiation target bombing with some possible collateral damage.

Zzotte

You don’t want to do chemo unless you have to. It does have negative effects on some people.

These side effects arise because chemotherapy drugs target rapidly dividing cells, which include not only cancer cells but also some healthy cells like those in the bone marrow, hair follicles, and digestive tract.

Radiation does not have these issues, it has its own issues, they are not nearly as bad as chemo side effects.

You have cancer, so "safe" has become a less important term. As @zzotte previously posted, radiation in more a single point target with the possible of nearby collateral damage. Chemo is the shotgun method of hitting most everything to knockout cancer with, hopefully, minimal damage to, well everything else. Your medical team should decide what you need at this point.
With prostate cancer, I had the usual targeted beam and then ARC radiation. I began to play Whack A Mole. Then two types of chemo. They all helped by buying time. Then, Pluvicto, which is working wonderfully.
All of these forms of treatments come with risk, but not nearly as risky as advancing cancer. You have to step back, take a breath, look at the big picture, remove emotion and use the available knowledge and options to make the best choice for you.