there's little difference between early and delayed treatment of an ovarian cancer recurrence. A study was done, and reported at ovariancancer dot org, showing that there is little value in treating an ovca recurrence when it's first detected by a rise in CA-125 readings. Looks like you can safely wait until there's other evidence of the relapse. I found this report in an October newsletter from the Ovarian Cancer National Alliance.
http://www.ovariancancer.org/2010/10/18/early-versus-delayed-treatment-of-relapsed-ovarian-cancer/