What is a tumour marker?
Tumour markers are generally a product your body makes that can be measured in a blood test that is also associated with specific cancers.
Tumour Markers help in clarifying whether or not a given ovarian mass is more or less likely to be a cancer but by themselves are NOT diagnostic of cancer
What are the most common tumour markers?
CA125, CEA, CA19.9, CA15.3, Alphafetoprotein, Inhibin, Beta HCG, HE4
What cancers are they associated with?
- CA125 is elevated in 85-90% of ovarian cancers but is also elevated in 1% of the normal population and in many other benign conditions such as endometriosis and fibroids. It is therefore said to be sensitive but not specific and unfortunately is only elevated in 50% of early ovarian cancers and at this point is NOT a reliable screening tool to detect ovarian cancer by itself. Because of the large number of confounding benign causes for elevating CA125 its interpretation in premenopausal women needs to be viewed cautiously.
- CEA – is typically associated with mucinous tumours of the ovaries and bowel cancers (smoking can also elevate this marker)
- CA19.9 – also typically associated with mucinous tumours of ovary or bowel and also pancreatic tumours
- CA15.3 – typically associated with breast cancer
- Alphafetoprotein - typically associated with yolk sac tumours of the ovary (germ cell tumour) a very reliable marker
- Inhibin – associated with granulosa cell tumours of the ovary – a very reliable marker
- BetaHCG – this is the hormone elevated normally in pregnancy but also some germ cell tumours and also in molar pregnancy (a condition which is largely a tumour of the placental tissue)
- HE4 – One of the newer tumor markers designed to improve the specificity of CA125 alone. This is increased in ovarian cancers but also can be elevated if there are kidney problems and also in lung tumours. It is used in combination with the Ca125 to calculate a ROMA (risk of malignancy Algorithm), which essentially predicts the likelihood of an ovarian mass being cancer. It is generally not elevated in endometriosis, which is sometimes very useful in differentiating younger patients with elevated CA125, and a mass that looks like an endometrioma from cancers.
If you have any concerns regarding results of elevated tumour markers and or family history of ovarian, breast or other gynaecological cancers Dr Land can advise the most appropriate course of action.