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 along with any symptoms suggesting possible ovarian malignancy: persistent abdominal distension, appetite change including increased satiety, pelvic or abdominal pain, increased urinary urgency and/or frequency.

A careful physical examination of the woman is essential and should include abdominal and vaginal examination, and examination to determine the presence or absence of local lymphadenopathy. Although clinical examination has poor sensitivity in the detection of ovarian masses, its importance lies in the evaluation of mass tenderness, mobility, nodularity and ascites.

In the acute presentation with pain the diagnosis of accident to the ovarian cyst should be considered (torsion, rupture, haemorrhage).

Imaging

A pelvic ultrasound is the single most effective way of evaluating a pelvic mass with transvaginal ultrasonography being preferable due to its increased sensitivity over transabdominal ultrasound. Routine use of CT or MRI is not indicated but where clinical or ultrasound suspicion exists, refer to Guidelines for Imaging of Gynaecological Malignancy (West of Scotland Cancer Network Guideline). CT of the abdomen and pelvis should be performed for masses with RMI >200 or in those with RMI <200 where clinical or ultrasound suspicion exists. MRI pelvis / lower abdomen should be performed in those with a complex mass which is difficult to characterise clinically or on ultrasound, or in young women (<30yrs) with suspected malignant tumour or a complex pelvic mass.

Blood tests

1. CA125 – a serum CA125 assay does not need to be undertaken in all premenopausal women when an ultrasonographic diagnosis of a simple ovarian cyst has been made, but should be performed in all other circumstances. However it must be recognised that it is unreliable in determining whether ovarian lesions are benign or malignant as CA125 is also raised in conditions such as fibroids, endometriosis, adenomyosis and pelvic infection. Note also that CA125 is primarily a marker for epithelial ovarian tumours but is only elevated in around 50% of early stage disease.
2.  LDH, αFP and hCG should be measured in all women under the age of 40 with a complex ovarian mass to exclude germ cell tumours.
3. Calculate RMI – see below.

Calculation of the RMI

RMI combines three presurgical features: serum CA125 (CA125); menopausal status (M); and ultrasound score (U).
The RMI is a product of the ultrasound scan score, the menopausal status and the serum CA125 level (IU/ml) as follows:     RMI = U x M x CA125

• 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.
• Postmenopausal can be defined as women who have not had a period for more than one year or women over the age of 50 who have had a hysterectomy.
• Serum CA125 is measured in IU/ml and can vary between zero to hundreds or even thousands of units.

• Women with an RMI of more than 200 should be discussed with the gynaecological oncology team and presented to the managed clinical network for gynaecological oncology after appropriate imaging as per WOSCAN Guidelines.
• Women with small (less than 50mm diameter) ovarian cysts generally do not require follow-up as these cysts are very likely to be physiological and almost all resolve within 3 menstrual cycles.
• Women with simple ovarian cysts of 50-70mm in diameter should have yearly ultrasound follow-up and those with larger simple cysts should be considered for either further imaging or surgical intervention.
• Ovarian cysts that persist or increase in size are unlikely to be functional and may warrant surgical management.
• The use of the combined oral contraceptive pill does not promote the resolution of ovarian cysts.

• A laparoscopic approach should be used whenever possible.
• Aspiration of ovarian cysts, either vaginally or laparoscopically, is less effective and is associated with a high rate of recurrence.
• Spillage of cyst contents should be avoided where possible as pre-operative and intra-operative assessment cannot absolutely preclude malignancy.
• Where minimal access surgery is employed, consideration should be given to the use of a tissue bag to avoid peritoneal spill of cystic contents, bearing in mind the likely pre-operative diagnosis.
• The possibility of oophorectomy must be discussed prior to surgery, documented in the notes and included in the consent form.