Tumour markers are biochemical substances associated with tumours, which can be identified in biological fluids (such as blood, urine, peritoneal fluid or fluid from cysts).
Although there is a correlation between marker level and tumour volume, its valuation is only complementary and should be associated with other diagnostic methods (ultrasound, MRI, diagnostic biopsy with pathologic examination, etc). Therefore, rather than to diagnose a tumour, the main tumour marker utility is to monitor the patient’s response to the treatment.
19% of all cancers have a gynaecological origin (ovarian, cervical, endometrial and vulvar). Most of these cancers occur in postmenopausal women and have an ovarian or endometrial origin. Cervical cancer occurs in young women, while vulvar cancer is more common in older women.
Survival patterns differ. The development stage of the cancer, when diagnosed, is the most powerful evolution predictor. In developed countries, most of these tumours are diagnosed early, except for ovarian cancer, which, in 75% of patients, is diagnosed in the third and fourth stage. Its approximate survival rate, after 5 years, is of 40%.
Most used tumour markers
There is a variety of “star” markers, frequently used in fertility clinics because of their greater sensitivity and specificity.
CA-125 is a routine test, used when there are suspicions of ovarian cancer. This test calculates the risk of developing the disease. It is also used to assess the patient’s response to cytostatic drugs or treatments and to predict tumour relapses before the manifestation of symptoms.
Other useful ovarian cancer markers are the beta-HCG and, in cases of germ cell tumours, the alpha-fetoprotein (AFP). The CA-19.9 is used to detect ovarian cancer with average specificity, while the SCC (squamous cell carcinoma) is used to detect cervical, vulvar and vaginal cancers. In other gynaecological tumours, the tumour markers role is more limited.