CA125

CA-125 is an antigenic determinant of a murine immunoglobulin Ig1 monoclonal antibody that was raised against an epithelial ovarian carcinoma cell line and is expressed in more than 80% of nonmucinous epithelial ovarian cancers.

CA-125 (also known as mucin 16 or MUC16) is a glycoprotein. CA-125 in humans is encoded by the MUC16 gene. CA-125 is used as a tumor marker because CA-125 concentrations may be elevated in the blood of some patients with ovarian cancer, but also in some benign conditions. CA-125 levels in serum are elevated in approximately 50 percent of women with the early stage the disease, and in over 80 percent of women with advanced ovarian cancer.

Monitoring CA-125serum levels is also useful for determining the response of a patient to ovarian cancer therapy as well as for predicting a patient’s prognosis after treatment. In general, persistence of high levels of CA-125 during therapy is associated with poor survival rates in patients.

Also, an increase in CA-125 levels in a patient during remission is a strong predictor of recurrence of ovarian cancer. The specificity of CA-125 is limited because CA-125 levels are elevated in approximately 1% of healthy women and fluctuate during the menstrual cycle. CA-125 is also increased in a variety of benign and malignant conditions