Ovarian Lesion

I previously posted a question regarding a hypoechoic lesion contained in my ovary.  I have since gone for a 2nd opinion.  Previous sonogram, April 8th, showed hypoechoic lesion contained in ovary.  Yesterday, the doctor said that it has gotton larger since then and is now in the ovary as well as outside the ovary.  I will be having surgery next week to remove it along w/ my ovary & tube on that side.  I have a lot of the symptoms associated with OvCa, and am just tired of not feeling good.  My sister died in 93, she had Endodermal Sinus Tumors.  Do these usually start inside the ovary?  Do benign tumors start inside the ovary & grow to the outside?  I saw the ultrasound as he was doing it, the mass was very "ragged" looking as compared to previous sonograms.  I appreciate your answers. Thank you.