Ovarian cancer antigen (CA-125) (CA-125)

“Ovarian cancer-specific antigen” as used clinically corresponds to ovarian cancer antigen CA-125, a high–molecular-weight surface glycoprotein tumor marker measured in blood rather than a discrete therapeutic receptor or enzyme target.[1][2][3][5][6][7][8] CA-125 is produced by cells of Müllerian epithelium (including ovarian, fallopian tube, and endometrial tissues), and elevated serum levels are found in more than 80% of advanced ovarian cancers and about 50% of early-stage cases, but also in numerous benign gynecologic and non‑gynecologic conditions.[2][3][4][6][7] Clinically, CA-125 is used primarily as a biomarker to help assess suspected ovarian cancer, to monitor response to therapy, and to detect recurrence, particularly in epithelial ovarian cancer, often alongside imaging and sometimes additional markers such as HE4, but it is not suitable as a standalone screening test in average‑risk populations because of both false positives and false negatives.[1][2][3][4][5][6][7][8]

Other names

Ovarian cancer antigenCancer antigen 125CA-125 tumor markerGlycoprotein antigenCA125