Indications:
The blood test CA 15.3 is useful in the effective control of an antitumor treatment.
Principle:
Circulating antigen, CA 15-3 is associated with breast cancer: it is recognized by monoclonal antibodies against membrane antigens of breast tumors.
Technique:
Levy of 2 mL of blood in a dry tube.
The assay method is radioimmunoassay or enzyme-immunoassay.
Results:
The normal value is less than 30 U / ml.
CA 15.3 rises in 10% of benign breast tumors, 30-50% of metastatic breast cancers and not in 80% of metastatic cancers.
His lack of sensitivity can not therefore make a cancer screening test, or a specific examination of breast cancer because high levels can also see if ovarian or lung cancer in chronic hepatitis , cirrhosis, or in case of autoimmune diseases.
However, this marker is useful in the monitoring of treated cancers: a rise in the rate can precede a few months the occurrence of metastases.
Cost:
B50 to B105.
Practical advice:
An isolated elevation of CA 15.3 in a patient treated for cancer has to fear the presence of metastases and advise treatment, although no secondary location is detectable clinically or radiologically.
