Leftkidney measures11.3x5.5cms enlarged in size rightkidney 9x5.5cms perapelvic cyst leftkidney causing mild calyectasis. Multiple renal cortical cys?

Multiple kidney cyst. The vast majority of renal cysts and benign simple cysts which are a symptomatic and causes no problems. It is not the same as polycystic kidney disease, where many cysts on both kidneys could lead to kidney failure. An ultrasound can determine if these are simple vs complex cysts, the latter could be worrisome. I suspect the kind you have could simply be followed over time; urologist will guide.