Hydronephrosis blocking left ureter

Hi guys, I’m recently diagnosed and had my CT scan and found out that my left ureter is partially blocked causing hydronephrosis to my left kidney causing it to swell. Does anyone has the same experience? He said I might need a stent to be placed before treatment. Also what concerns me is at the report he said usually it might be neoplastic invasion or the tumor pressing on the urethra which I hope is the case. Or else the invasion might mean the cancer had spread there. I’m having pain everyday on my left pelvic area and left lower back that I take pain relief everyday. My oncologist appointment won’t be til 10 days from now. I wish I can be seen more quickly. Any similar experience and advise please. Thank you. Xx