Patients with recurrent ovarian cancer who received either single agent PLD, TPT, or both were included. CA-125 levels were evaluated prior to initiation of chemotherapy and thereafter for each additional cycle. The Rustin criteria were utilized to evaluate CA-125 response.
Fifty-four of 120 patients were judged to be responders. When comparing responders to non-responders, as expected, the majority of responders demonstrated a decrease after each of the first 4 cycles. However, nearly 50%of responders who received PLD demonstrated an increase in CA-125 after cycle 1. There were no responders who demonstrated two successive rises in CA-125.
The majority of patients with recurrent ovarian cancer who will ultimately manifest a CA-125 response to novel agents, such as TPT or PLD, will demonstrate a decrease following each cycle. An initial increase in CA-125 should not mandate discontinuation of current therapy, but a successive rise over two or more cycles reliably predicts that a treatment response ultimately is unlikely.