Ovarian Cysts Flashcards
Definition of ovarian cysts
Ovarian cysts are fluid filled sacs in the ovarian tissue. The vast majority of identified cysts are benign.
Incidence and prognosis of ovarian cysts in pre-menopausal women
Around 8% of pre-menopausal women have one
In premenopausal women almost all ovarian masses and cysts are benign (incidence of symptomatic ovarian cyst is around 1:1000 premenopausal women)
* Functional or simple ovarian cysts (thin-walled cysts without internal structures) which are less than 5cm maximum diameter usually resolve over 2–3 menstrual cycles without the need for intervention
Incidence and prognosis of ovarian cysts in post-menopausal women
Incidence in post-menopausal women is anywhere between 5 and 17% (increasing incidence due to increased imaging leading to identification of incidental cysts)
Cystic lesions in the postmenopausal ovary should only be reported as ovarian cysts, and considered significant, if they are 1 cm or more in size. However, adnexal cysts which are 5cm or smaller are rarely malignant (same as premenopausal)
Types of ovarian cyst
- Endometrioma: A cyst (containing blood and endometrial tissue) formed via endometrial tissue on the ovary
- Functional cysts (occur around ovulation)
- Follicular- unruptured Graffian follicle (form following failed rupture of the dominant follicle or failed degeneration of the non-dominant follicle)
- Luteal- following rupture the follicle reseals and distends with fluid
- Haemorrhagic- bleeding into a functional cyst
Risk factors for developing cysts
PCOS, obesity, early menarche, 1st trimester pregnancy, endometriosis
Complications of ovarian cysts
- Become haemorrhagic: Bleeding inside cysts, More common with follicular and corpus luteal cysts
- Rupture: Can happen spontaneously but more frequent after sexual intercourse
- Ovarian torsion: When ovary twists around the suspensory ligaments, Risk factor for this is when ovary is 5cm or larger
- Infection
- Malignant change
Presentation of ovarian cysts
- May be asymptomatic
- May present with lower abdo pain, deep dyspareunia, pressure symptoms, abdominal swelling (common in larger cysts)
- Acute accident: severe right/ left iliac fossa pain accompanied by vomiting in torsion (indicates torsion, haemorrhage, rupture)
Investigation of ovarian cysts in premenopausal women
- A thorough medical history should be taken from the woman with specific attention to risk factors or protective factors for ovarian malignancy and a family history of ovarian or breast cancer. Symptoms suggestive of endometriosis should be specifically considered
- Other symptoms to be considered: suggesting ovarian malignancy- persistent abdominal distension, appetite change including increased satiety, pelvic or abdominal pain, increased urinary urgency and/or frequency
- TVUSS
- A serum CA-125 assay does not need to be undertaken in all premenopausal women when an ultrasonographic diagnosis of a simple ovarian cyst has been made
- Unreliable in premenopausal women de to false positive risk
- Lactate dehydrogenase (LDH), α-FP and hCG should be measured in all women under age 40 with a complex ovarian mass because of the possibility of germ cell tumours
- Calculation of Risk of malignancy index (RMI-1)
Investigation of ovarian cysts in postmenopausal women
- A thorough medical history should be taken from the woman, with specific attention to risk factors and symptoms suggestive of ovarian malignancy, FHx of ovarian, bowel, breast cancer
- A full physical examination of the woman is essential and should include body mass index (BMI), abdominal examination to detect ascites and characterise any palpable mass, and vaginal examination
- CA125- allows calculation of RMI (normal value does not exclude diagnosis)
- Non-malignant gynaecological conditions such as PID, fibroids, acute events in benign cysts (e.g. torsion or haemorrhage) and endometriosis can all result in an increased CA125 level
- TVUSS- single most effective way of evaluating ovarian cysts in postmenopausal women- transabdominal USS should NOT be used in solation
- Colour doppler, CT, MRI and PET-CT are not routinely used in the initial evaluation of ovarian cyst in postmenopausal women
- CT pelvis abdomen, MRI are second line investigations
- Calculation of Risk of malignancy index (RMI-1)
- RMI I score with a threshold of 200 is recommended to predict the likelihood of ovarian cancer and to plan further management
- CT of the abdomen and pelvis should be performed for all postmenopausal women with ovarian cysts who have a RMI I score greater than or equal to 200, with onward referral to a gynaecological oncology MDT
Five features of simple cysts on USS
- Round or oval shape
- Thin or imperceptible walls
- Posterior acoustic enhancement
- Anechoic fluid
- Absence of septations or nodules
Worrying deatures in complex cysts that are assocaited with risk of malignancy
- Complete septation (i.e multiocular cysts)
- Solid nodules
- Papillary projections
How do we calculate RMI-1
Product of serum CA125, menopausal status and USS
* The ultrasound result is scored 1 point for each of the following characteristics: multilocular cysts, solid areas, metastases, ascites and bilateral lesions. U = 0 (for an ultrasound score of 0), U = 1 (for an ultrasound score of 1), U = 3 (for an ultrasound score of 2–5).
* The menopausal status is scored as 1 = premenopausal and 3 = postmenopausal.
* Serum CA125 is measured in iu/ml and can vary between zero and hundreds or even thousands of units
What is the IOTA classification
Based on specific USS markers and has comparable sensitivity and specificity to RMI
Management of ovarian cysts in premenopausal women
- Women with small (less than 5cm diameter) simple ovarian cysts generally do not require follow-up as these cysts are very likely to be physiological and almost always resolve within 3 menstrual cycles
- Women with simple ovarian cysts of 50-70mm in dimeter should have yearly USS follow-up and those with larger simple cysts should be considered for further MRI or surgical intervention
- HOWEVER, ovarian cysts that persist or increase in size are unlikely to be functional and warrant surgical management
- Should remove cysts laparoscopically if possible (larger cysts may require laparotomy)
- Complex cysts should also be removed via cystectomy
Management of ovarian cysts in postmenopausal women
- Asymptomatic, siple, unilateral, uniocular cysts less than 5cm in diameter have a low risk of malignancy. They should be managed conservatively, with repeat evaluation in 4-6 months (as long as normal CA125)
- It is reasonable to discharge in 1 year if the cyst does not change in size
- If a woman is symptomatic, further surgical evaluation is necessary
- Aspiration is not recommended except for the purpose of symptom control in women unfit for surgery
- Women with an RMI1 of less than 200 are available for laparoscopic management
- Laparoscopic management of ovarian cysts in postmenopausal women should comprise bilateral salpingo-oophorectomy rather than cystectomy (even when risk of malignancy is low)
- Full staging laparotomy will be required if evidence of malignancy is revealed
- Where possible, the surgical specimen should be removed without intraperitoneal spillage in a laparoscopic retrieval bag via the umbilical port
- All ovarian cysts that are suspicious of malignancy in a postmenopausal woman, as indicated by a RMI I greater than or equal to 200, CT findings, clinical assessment or findings at laparoscopy, require a full laparotomy and staging procedure.
- If a malignancy is revealed during laparoscopy or from subsequent histology, it is recommended that the woman be referred to a cancer centre for further management
Presentation of cyst accidents
