Anne,
Here's a link to a study posted on UW's clinical trial page; following is the eligibility description:
Study Population / Indication Breast cancer: Stage III or Stage IV breast cancer in remission and defined as "no evidence of disease."
Ovarian cancer: Stage III or IV. All subjects must be in first complete remission with a normal and stable CA125. Two sequential normal CA 125 values must be documented, the most recent within thirty days of enrollment in study.
http://depts.washington.edu/tumorvac/synopsis1.html
I'd suggest contacting them to find out if the study is open for enrollment yet, and if you're mom is interested in the study she can ask for a copy of the consent form to be mailed. It will have much more detailed information and is good to have to preview.
Love, Lolly