Over the years I have seen many patients with significant endometriosis including those unfortunately affected with deep invasive disease and also ovarian involvement or endometriomas commonly known as chocolate cysts. We had been aware of a link between larger endometriomas and the subsequent development of rare forms of ovarian cancer for some years although the exact relationship at this stage is unclear. A recent disturbing large study has compared over 70,000 women with endometriosis to women without endometriosis. There were almost 600 women with ovarian cancer identified. Patients with deep infiltrating endometriosis and/or ovarian endometriomas had an almost 10 times the risk of ovarian cancer when compared with individuals without endometriosis.
At this stage the reasons for this link are unknown although there is emerging evidence of an overlapping genetic predisposition to both endometriosis and certain types of ovarian cancer.
I have been suggesting ongoing surveillance for my patients with endometriomas but I am now beginning to think it may be appropriate to contemplate prophylactic oophorectomy at menopause to decrease the risk. Unfortunately the very nature of the disease is such that this may not be a simple procedure and I believe only experienced surgeons should be undertaking this
