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Cancer Antigen 125 (CA 125)

What is CA 125?

CA 125 is a tumour marker that belongs to a group of hybridoma-defined antigens. It is primarily used in the monitoring and management of certain cancers, particularly ovarian cancer. CA 125 levels are measured through a blood test and can help assess disease progression and response to treatment.

Elevated CA 125 in Malignant Conditions

While CA 125 is most commonly associated with serous ovarian carcinoma, elevated levels may also be seen in other types of cancers, including:

Cervical cancer

Liver cancer

Pancreatic cancer

Lung cancer

Colon and stomach cancer

Biliary tract, uterine, fallopian tube, breast, and endometrial carcinomas

Elevated CA 125 in Non-Malignant Conditions

Increased CA 125 levels are not exclusive to cancer and may also be found in several nonmalignant conditions, such as:

Cirrhosis and hepatitis

Endometriosis

Ovarian cysts

Pelvic inflammatory disease (PID)

First trimester of pregnancy

During the menstrual cycle

These factors contribute to the marker’s limited specificity, requiring careful clinical interpretation.

Clinical Use of CA 125 Testing

Despite its lack of specificity, CA 125 remains the most valuable tumour marker for:

Monitoring treatment response in serous ovarian carcinoma

Predicting recurrence of ovarian cancer

Assessing the presence of intraperitoneal tumours

CA 125 Blood Testing in Slough and Surrounding Areas

Private CA 125 testing is available in Slough, Windsor, Langley, Burnham, and Maidenhead. This test plays a crucial role in the ongoing management of ovarian cancer and other related conditions. When used alongside imaging and clinical evaluation, CA 125 testing supports early detection, treatment monitoring, and improved patient outcomes in women’s health and oncology care.