What is ovarian remnant syndrome?
Ovarian remnant syndrome is a rare condition, that may occur following removal of one or both ovaries for endometriosis where (microscopic) endometriosis tissue that unknowingly has been left behind, can re-grow and become functional again by continuing to produce hormones. This can occur even years following the original surgery.
What are the signs and symptoms?
The most common symptom of Ovarian Remnant Syndrome is pelvic pain. Less frequently seen symptoms include a pelvic mass, or the absence of menopausal symptoms after surgery. If menopausal symptoms weren’t experienced after surgery to remove both ovaries, this would suggest that the patient may still be producing hormones and ovarian tissue may have been left behind. Some people with ovarian remnant syndrome also have symptoms similar to endometriosis, such as painful intercourse, urinary or bowel symptoms.
It may be possible that some people with ovarian remnant syndrome do not present with any symptoms, but the rate of this is unknown.
What are the causes?
Ovarian remnant syndrome is caused by incomplete removal of the ovarian tissue at the time of surgery to remove the ovaries. It has a higher risk of occurring in patients with endometriosis, pelvic inflammatory disease, pelvic adhesive disease, or after difficult or repeated surgery.
Pelvic adhesions are scar tissue that may cause body organs to stick to one another and can cause a range of problems. Pelvic adhesions are most often found on the ovaries, uterus, and bladder. Pelvic adhesions raise the risk of ovarian remnant syndrome because there is an increased risk of ovarian tissue being embedded into nearby organs, making complete excision of all ovarian tissue more difficult and complex. Pelvic adhesions are more common in people who have pre-existing conditions such as endometriosis or previous surgeries.
Intraoperative bleeding, anatomical abnormalities (where ovaries are located in an unusual location) and an unskilled surgeon or poor surgical technique may also increase the risk of ovarian remnant syndrome.
How is ovarian remnant syndrome diagnosed?
To be diagnosed with ovarian remnant syndrome, a patient must have had an oophorectomy (removal of ovaries). A doctor may consider ovarian remnant syndrome in women who have undergone oophorectomy and have associated symptoms, the presence of a pelvic mass, or evidence of persistent ovarian function. A pelvic ultrasound is performed to look for a pelvic mass, or presence of residual ovarian tissue. A doctor may also perform blood tests to assess levels of follicle-stimulating hormone (FSH) and estradiol.
A biopsy of tissue which is then examined under a microscope is required to confirm the diagnosis.
What are the treatment options?
The treatment may also be performed at the same time as biopsy, where the surgeon removes the remnant ovarian tissue in the same procedure. This is completed via a laparoscopic (keyhole) approach.
Treatment is primarily for those who develop symptoms, a pelvic mass, or a high risk of ovarian cancer (such as BRCA gene carriers). There is a very small chance that the remaining ovarian tissue can develop into ovarian cancer.
If surgery is not an option, treatment may include hormonal therapy to suppress ovarian function.
Preventing ovarian remnant syndrome
When conducting oophorectomy I employ all surgical techniques necessary to prevent and minimise this condition occurring, including excision of all pelvic adhesions.
For example, I always use a retroperitoneal approach to remove ovaries where I generate a safety margin around the ovary for the aim of complete removal. However, and while this minimises the risks of ovarian remnant syndrome, it does not completely exclude it.
Surgery to remove remnant ovarian tissue is complex, carries risks for surgical complications and should ideally be performed by someone with experience in advanced laparoscopic surgery.
If you wish to discuss assessment and treatment of pelvic pain after oophorectomy with Dr Obermair, please enquire about an appointment via the contact us page.