What Does The Ultrasound Report Indicate?

I had went for a follow up ultrasound Thursday aafternoon. I was told that the left cyst had either bust or shrunk due to the contraceptive i was given,however my right cyst which was known to be very large was no a fluid filled tube. the doctor had told me it was not going to get better, that if i were to remove it would be fine since its useless he said and im young my other tybe would allow me to have no trouble in having children in the future. My question is are there other options, is it dangerous to leave, could it be misdiagnosed ?