I have ovarian cysts are these curable and would they turn into cancer?

i never had my menstrual period since 21 yrs old and dr said its menopause but at 21yrs old they wanted to do more tests on me but to much of a hle plus i felt like a a freak they couldn't figure this out and some dr.s kept sending me here there then i did have one operation.well any way my ? was how do you get these ovarian cysts?