dysgerminoma?

 I had a concerning ultra sound. I am due to have a  total hysterectomy at the end of July for adenomyosis and pcos so my Ob/Gyn decided to do a ultrasound.  My right ovary was normal but my left ovary was significantly bigger.  No one wants to hear a ob/gyn say "What is that? I wonder what that is?  I've never seen this before? I can't wait to get in there to see what is going on" That's exactly what I heard. My doctor went on to say my ovary was on top of my uterus and much bigger then my right. She looked concerned but noticed I was concerned.  So she made a joke.  She remembered I donated a kidney   She said my lefty ovary was mimicking my kidney. I think she was just trying get my my mind off of what she just blurted out.  She took several pictures and said because I was having a hysterectomy very soon she didnt want to order other test and left things at she'll see me in 6 weeks for a follow up on medication and to pencil in my surgery date and time. I did sneak a peak at my folder when she went to clip the ultra soundBecause because I saw her write something.  At the bottom I saw a note saying oncology consult.   I am here to ask the woman diagnosed with dysgerminoma  how the doctor discovered they had it?  Did it start with a ultrasound? Cat scan? MRI? Will I have to wait for my hysterectomy?  I am sticking to my motto "hope for the best but expect the worse" I just feel like there is something wrong and I can't shake it. I am never like this I always have a rational mind.