CA125 may be elevated in many physiological and pathological conditions, with gynaecological and non-gynaecological causes. These conditions are summarised in the table below.
Elevated CA125: investigation & management, Gynaecology (1113)
Warning
Objectives
To provide guidance on how to investigate women where a raised CA125 is found
Audience
Healthcare providers in primary and secondary care in Great Glasgow and Clyde (GGC)
CA125 is considered to be the best available marker for epithelial ovarian cancer.
The widely accepted normal range of CA125 in GGC is 0-35 IU/ml.
Primary Care
Ovarian cancer presenting features often include non-specific abdominal symptoms that are persistent and frequent and there may also be a palpable pelvic mass or ascites.
Examination and investigations that should be arranged are
- Abdominal palpation
- CA125 blood serum level measurement (best taken out with menstruation)
- Urgent suspected cancer (USOC) pelvic ultrasound scan (ideally transvaginal assessment)
These investigations should be undertaken in the following patients:
- Women (especially those aged 50 or over) with one or more unexplained symptoms occurring most days over the last four weeks, including:
- abdominal distension or persistent bloating
- feeling full quickly, difficulty eating, or loss of appetite
- pelvic or abdominal pain
- increased urinary urgency and/or frequency
- change in bowel habit
- Women aged 50 or over who have experienced new symptoms within the last 12 months suggestive of irritable bowel syndrome
Important note: CA125 is not raised in all cases of ovarian cancer, therefore, CA125 should always be done in conjunction with a pelvic USS in women with symptoms or signs suspicious of ovarian cancer.
Additionally if physical examination in primary care suggests ascites and or a pelvic or abdominal mass (which is not obviously uterine fibroids) they should be referred urgently for review in gynaecology and referral should not be delayed whilst waiting for CA125 result.
Secondary Care
Abnormal Ultrasound Scan or imaging findings – premenopausal women
The Royal College of Obstetricians and Gynaecologists (RCOG) advises that a CA125 level is not routinely needed for the diagnosis of a simple cysts in premenopausal women.
If germ cell origin tumours are suspected following imaging (e.g. women < 40yrs), αFP, βHCG and LDH are recommended in addition to CA125.
Please see GGC guidelines for further details Ovarian Masses in premenopausal adults, assessment and management (514) | Right Decisions
Abnormal Ultrasound Scan or imaging findings – postmenopausal women
A CA125 level should be measured in all postmenopausal women with a cystic lesion of 3cm or more. This should be used in conjunction with the USS findings to calculate the Risk of Malignancy Index Score (RMI). Please see GGC guidelines for further details Ovarian Pathology in Post-Menopausal Adults (549) | Right Decisions.
Normal pelvic ultrasound scan or imaging & Raised CA125
If a CA125 has been measured prior to imaging, a normal ultrasound can exclude ovarian cancer with a high degree of confidence.
Postmenopausal ovaries will appear smaller and more homogenous compared to those found in pre-menopausal women. It is therefore common not to visualize the ovaries on ultrasound in a postmenopausal woman. For completeness an abdominal examination and bimanual examination may be undertaken to assess for potential non pelvic masses.
In the presence of a normal pelvic ultrasound scan or imaging, there is no clear evidence to repeat a CA125 measurement. However, extrapolating from ovarian cyst data, a rapidly rising CA125 is more likely to be associated with malignancy, therefore consider a repeat CA125 after 8 weeks to assess trend. If significantly rising, further imaging by urgent CT scan of abdomen and pelvis should be arranged.
If no gynaecological cause identified, patient should be referred back to GP to assess for other clinical causes of symptoms and investigate or refer as appropriate.
