CA125 and Breast Cancer: Any relationship?

Hi,

My wife (37 years old) just underwent a year of treatment for metastatic Breast Cancer with 2 spots on the spine (CEF chemotherapy, lumpectomy, Taxol chemotherapy, breast radiation, Oopherectomy) and has been on Tamoxifen for 3 months now. During treatment the Doc mentioned that the disease seemed 'less aggressive' and also chemo sensitive since first round with CEF had shrunk all sites by 50 - 60%.

The CA-125 was done prior to Oopherectomy in August and was at 153 and they did find deposits in the Ovaries which were identified by the histopath as 'Breast Cancer' but with lower percentage of ER/PR +ve cells. Her recent PET-CT scan showed a lot of new hotspots in the spine and skeleton with high SUVs (above 8) and the CA125 is now at 887.

She is asymptomatic with no pain.

The Onco now feels she has 'Ovarian Cancer' as well which was earlier missed. He wants to begin Chemo with Carboplatin.
Is the diagnosis correct?
Another Doc we consulted felt that current findings (CA125 and PET hotspots) could still be explained by exisiting Breast Cancer and current hormonal treatment should be continued until she indicates any other symptoms such as any pain etc.

Please advise your thoughts.

What should be the next mode of treatment?

Thanks for your help and support.
Regards,
Al

[Cleveland Clinic]

Dear Al:  The CA-125 is a non-specific tumor marker that can be elevated for a variety of reasons.  It is best applied to tracking a known diagnosis of ovarian cancer.  It's significance in breast cancer is unknown.  If there is concern that your wife has ovarian cancer, the pathology slides from the oopherectomy should be checked.  Though there are no rules in terms of how a cancer may behave, skeletal metastases are more common in breast cancer than in ovarian cancer.