Diagnosing ovarian cancer (information for GPs)

GPs play a crucial role in ruling out ovarian cancer at the first suspicion, and ensuring women are diagnosed at the earliest possible stage. National guidelines set out how GPs should assess and refer women with symptoms that could be caused by ovarian cancer.

Here you'll find information covering:

Symptoms

Guidance issued by NICE and SIGN recognise the following symptoms most commonly associated with ovarian cancer. 

Symptoms are frequent (usually occurring 12 times a month or more) and persistent, and include:

  • persistent abdominal distension (women often refer to this as bloating)
  • early satiety and/or loss of appetite
  • pelvic or abdominal pain
  • urinary urgency and/or frequency.

Occasionally there can be other symptoms such as unexplained weight loss, unexplained fatigue, and unexplained changes in bowel habit. Any post-menopausal bleeding requires urgent investigation.

Symptoms of ovarian cancer are usually more persistent and frequent than similar symptoms caused by other conditions like irritable bowel syndrome.

Risk factors 

The two greatest risk factors for ovarian cancer are age and family history. Almost 85 per cent of all diagnosed cases occur in women over the age of 50.

Women with a family history (maternal or paternal) of not only ovarian but also breast cancer could be at greater risk of developing ovarian cancer.

Find out more about risk factors

Diagnostic tests

NICE gives clear guidance on how to manage symptomatic women.

  • If physical examination identifies ascites and/or a pelvic or abdominal mass, refer urgently to gynae-oncology.
  • Women reporting persistent or frequent symptoms highly indicative of ovarian cancer should be given a serum CA125 test, particularly if they are age 50 or over.
  • Women age 50 or over presenting with new onset IBS should be given a serum CA125 test.
  • If the CA125 is greater than 35 IU/ml arrange an urgent ultrasound scan of the abdomen and pelvis.
  • If the ultrasound suggests ovarian cancer then the woman should be referred to gynae-oncology.
  • Advise women with a normal CA125, or a CA125 greater than 35 IU/ml but a normal ultrasound to return for re-assessment within one month if symptoms continue. If concerns persist refer urgently to gynae-oncology.

Scottish SIGN guidance and the Scottish referral guidelines for suspected cancer recommends performing abdominal palpation on women presenting with symptoms of ovarian cancer, and referring them for a CA125 serum test and urgent pelvic ultrasound scan.

If the pelvic ultrasound is abnormal and/or the CA125 greater than 35 IU/ml women should be referred urgently to secondary care for further investigation.

Our Diagnostic tests for ovarian cancer: A guide for primary care fact sheet [PDF] will help GPs and GP nurses understand national guidance for referring patients for diagnostic tests. It gives an insight into the limitations of CA125 and offers suggestions for safety-netting.

Women undergoing tests for suspected ovarian cancer can contact our support line for confidential support and information.

Common problems diagnosing ovarian cancer

Nearly two-thirds of women diagnosed with ovarian cancer will have late-stage disease at the point of diagnosis. The challenge for primary care professionals is in the detective work required to identify suspected cases of ovarian cancer from cases of non-malignant disease.

  • Misdiagnosis: women presenting with symptoms of ovarian cancer often receive a diagnosis of IBS, diverticulitis, urinary tract infection or changing menopausal status. NICE and SIGN clinical guidelines advise that women over 50 rarely present with IBS for the first time, in these cases serum CA125 should be measured.
  • Bloating: abdominal distention is a high-risk symptom, warranting rapid investigation (increased abdominal size/persistent bloating, not bloating that comes and goes). Women often using the word 'bloating' to describe both abdominal distention as well as fluctuating bloating and discomfort. Since persistent distension is a key indicator of ovarian cancer and fluctuating bloating is not, this can be a challenge.
  • Follow-up consultation: women often fail to return for a follow up consultation even if their symptoms persist. Healthcare professionals should encourage women to book a follow-up consultation within one month if symptoms persist. Suggesting that patients keep a record of symptom frequency and persistency may help a follow-up appointment. Patients can use a copy of our symptoms diary [PDF] to help them. 

Screening programmes

There is currently no national screening programme for ovarian cancer in the UK.

Two major clinical trials have assessed the impact of screening on ovarian cancer mortality both among women in the general population and among those at increased risk of ovarian cancer due to a family history.

Both trials used a multimodal screening (MMS) method. In this approach an algorithm known as the ROCA (risk of ovarian cancer algorithm) test was used. This establishes an individual's baseline level of CA125 and reveals an individualised profile of change over time rather than relying on a single CA125 fixed cut-off value. Transvaginal ultrasound (TVU) is also used as part of the MMS protocol.

United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) study

This study recruited 200,000 women between the ages 50–74 from centres across the UK. The trial was only for women without symptoms of ovarian cancer who aren't at high risk of developing the disease due to a strong family history of either breast or ovarian cancer.  Participants were assigned to one of three study groups – a control group, MMS group or yearly TVU group.

Results published in 'The Lancet' show that neither MMS or annual TVU led to a reduction in mortality. On this basis, implementation of a national screening programme for ovarian cancer is not possible.

CA125 and TVU and are considered effective diagnostic tests for investigating women presenting with symptoms of ovarian cancer, and are recommended by NICE and SMC for use in primary care.

For free information on managing symptomatic women in primary care, explore our training modules.

United Kingdom Familial Ovarian Cancer Screening Study (UKFOCSS)

This study looked at whether regular screening is beneficial for women at high-risk of developing ovarian cancer. Over 4,000 women with a 1 in 10 or greater risk of developing ovarian cancer due to family history or known gene mutation took part in the study. Results published in the 'Journal of Clinical Oncology' indicated that four-monthly screening with the ROCA Test may be an option for these women until they decide to undergo surgery; however, this has not yet be implemented.