Wow. UTUC is supposed to be very "vigorous" and hard to beat, not to mention uncommon. You are a year further into treatment than I. It is difficult to know what to expect. My oncologist is optimistic as I am only 61.5 yrs old without any other health issues and I blasted through the chemo without any real issues except loss of apetite and a bit of hair thinning. Hair thinning was a bit of a bonus on not having to shave my legs in the summer. : )
My cancer definitely started in the kidney pelvis. Surgery was complex as the kidney was stuck to the adrenal gland and both were stuck to my diaphram. The tumour extended into both the renal vein and renal artery which were stuck to adjacent tissue. They had to cut into my diaphram in two spots and the inferior vena cava in one spot. Only the kidney end of the ureter was compromised, so I had hoped to avoid bladder issues. I have a lovely 15 inch scar down my abdomen.
I was lucky that my family doctor sent me to a good oncologist. She had a brief battle with the first surgeon my first urologist sent me to over chemo before surgery. The chemo stopped it from progressing and the new second surgeon agreed on the chemo decision. Unfortunately the first urologist did not know anything about UTUC and delayed a second biopsy attempt by 2 months (ureteroscopy didn't work as they couldn't access the kidney through the top of the ureter) by asking for a second opinion (that took 3 weeks). Then it took him 2 weeks after the external biopsy result showed high grade muscle invasive UTUC to contact me. December 2021 CT scan had half the kidney gone, the mid-March 2022 CT had entire kidney gone. The first urologist's comment was "I see hundreds of high grade cancer reports so why should I have jumped on this one". He is no longer my urologist and I am putting a complaint in with the Patient Relation board at the hospital (not one in the USA) about his attitude. If he had not delayed a total of 3 months, perhaps it would have been stopped at the T3 stage. My oncologist said she wished she had seen me sooner. First urologist did not even consider refering me to an oncologist. The current urologist seems to be more humane.
I hope that your cancer will respond and give you at least a few years without hearing the word cancer.