I suspect that you may have been given brachytherapy at least in part because of the positive pelvic washings. Otherwise they may not have done any treatment beyond the hysterectomy. Undertreatment is bad, but as terradean noted, overtreatment is bad too. You may have lasting side effects and have no way of knowing whether it was necessary or not.

If the doctors who come up with the treatment guidelines think that positive pelvic washings should not be included in the treatment algorithm, it's unlikely that the people on this board will have much useful to add. I took a quick look at this literature, and it looked like a mess to me.

I agree that being in this situation is upsetting. I am also concerned that my surveillance program (a pelvic exam every 3 months) is unlikely to detect recurrences before they become large and problematic. But I have concluded that I can't do anything about it and that I just have to accept it. I'm thinking positive thoughts and putting it out of my mind.

Do you know the results of the gene tests from your tumor? They should have tested it for a gene called p53 and for 4 genes involved in something called mismatch repair (abbreviated MMR). If those are all negative, a possibility that might make you feel better, IF you got the right result, would be a test for mutations in a gene called POLE. The recurrence rate for POLE-mutated endometrial cancers, which make up ~10% of all endometrial cancers, is extremely low. The national treatment guidelines actually say that endometrial tumors should be tested for POLE, but I learned that in practice, they currently are not in the US. I suspect that this is because insurance won't cover it. I was unwilling to start chemo without having my tumor tested for POLE, so I had my specimen sent to Stanford for the POLE test. It cost me $450 out of pocket in September 2022. It's a bit like buying a lottery ticket: you have a 10%+ chance that the result will be positive, and you will be really happy. If it's negative, you're just out $450 (or whatever the price is now.) Mine was negative, but I'm still glad I did it.