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please can you advise me on the importance of CA125.

mine was 1250 then after surgery 46 a week later now 56.

i have ppc and have had a bowel obstruction . Since then ormentum taken away and bowel restriction. I caught pneumonia from surgery and had cardiac arrest so have had to build strength up over 3 months.

i was delighted at CA125 being low but feel that no one else mentions it. 

I ask for it to be done and written in chemo book, 

how important is it? 


Ellen M-Macmillan
Posted by

Hi Lemonade,

Thanks for getting in touch with us.

It sounds as if you’ve been through such a lot. It can be difficult enough having to cope with a diagnosis of cancer without the added stress of having complications after surgery.

Primary Peritoneal Cancer(PPC) is a rare cancer that starts in the thin tissue lining the inside of the abdomen. PPC cells are the same as the most common type of ovarian cancer cells.  This is because the lining of the abdomen and the surface of the ovary develop from the same embryonic tissue in the womb. So, doctors treat PPC in the same way as ovarian cancer.

Primary peritoneal cancers often produce a protein called CA125 that shows up in a blood test. Doctors call this a tumour marker.

A raised level of CA125 can be a sign of either PPC, ovarian cancer or fallopian tube cancer. If someone has a high level at diagnosis, then doctors can use this to monitor treatment effects. They can also use this to detect if a cancer is coming back. It’s good news that your level has come down. Having a slight increase doesn’t mean that your cancer has come back, as it can be raised due to inflammation too.

Doctors usually measure it before you start treatment. If you had high levels, your doctor will expect the level to fall as the chemotherapy destroys the cancer cells.

Some doctors monitor someone’s CA125 blood tests before each chemotherapy treatment to see how well the treatment is working. Others recommend that the test is done after your whole course of chemotherapy has finished.

Doctors can also use scans, such as a CT scan, to see how well treatment has worked. They might recommend that you have a scan after 3 or 6 cycles of chemotherapy

I see from your activity that you’re concerned because the doctors/nurses don’t seem to be checking your CA125 levels. Don’t worry about talking to your team about your concerns. They will be able to discuss your blood results in more detail.

Best wishes and take care.

Ellen-Macmillan Online Digital Nurse Specialist.