How effective are the CA 27.29 test?

I am a two year survivor of stage II breast cancer.  I have been give the CA 27.29 tumor marker test for the past year.  It was usually staying around 32 to 34.  The last three months it has gone from 39.4 to 30.9 to 39.6 this last week.  Can you tell me the reasons this marker is going up and down?

[CCF-RN,MSN-rf]

Dear flaaggie:  The use of CA27.29 to detect breast cancer recurrence at present is controversial. When other alternative causes of elevated CA 27.29 have been eliminated, an abnormal test result may indicate recurrent disease. However, there has been no evidence to date that treatment based solely on CA27.29 elevation significantly improves overall survival rates. The American Society of Clinical Oncologists (last update in 1997) guidelines state that at present the data are insufficient to recommend routine use of CA27.29 for screening, diagnosis, staging or surveillance following primary treatment. Although an increasing CA 27.29 can detect recurrence following primary treatment, the clinical benefit is not established. When discussing clinical benefit they are talking about will this have an effect on disease free or overall survival? Will the benefit of early treatment outweigh the risks of treatment side effects? The answers or evidence in regards to these questions is not currently available.

Elevated levels may be found in-patients with other diseases such as ovarian cysts, uterine fibroids, intestinal or colonic problems, medication; Paxil, hepatitis, tuberculosis, systemic lupus.

Whether a person should proceed with treatment based solely on the elevated CA27.29 would have to be seriously weighed based on risks of treatment and unknown overall benefit.  In most cases, a CA27.29 would not be sufficient information on which to base treatment decisions.

[GEMC]

In October 2001 my wife's CA 27.29 went from 50+/- to 150=/-.  Bone and CT scans indicated mestastasic bone CA.  Treatment followed.  In Oct 2002 CA 27.29 jumped to 320+/-.  CT scan in Jan indicated some activity in old lesions and bone and CT in March indicated growth of old lesions and new lesions.  We will start newround of chemo today.  In two years I have been unable to get a good answer to, How high can CA 27.29 go? And when is it too high?