Tamoxifen causing large ovarian cyst

I agreed with my gyno to monitor the cyst by having a pelvic ultrasound in three months time before I decided what I would do.  That ultrasound showed that the 5cm cyst had shrunk to 4cm but also now had a 4cm cyst on the other ovary.  I left it for another three months and had another ultrasound, that showed both cysts had completely vanished.  I now have no pain or discomfort, I did not have my ovaries removed, and I am nearly five years on tamoxifen now with another five to go.  As long as I have no bleeding the gyno is happy for me to continue as I am.  My onocologist told me all along that this is what happens the cysts come and the cysts go.  I am very relieved I did not choose to have any further surgery and at the moment am continuing comfortably on the tamoxifen apart from my aches and pains which are also a side effect!!