An increase in CA125 is an early sign of ovarian cancer recurrence. “What causes huge confusion around the world is that it is not currently known whether there is any benefit from doing this regular tumor marker blood test,” Dr. Gordon Rustin from Mount Vernon Cancer Center, Hertfordshire, UK told the conference. “What we do know is that it causes huge amount of anxiety among women.”
Dr. Rustin and colleagues studied 529 women with ovarian cancer in complete remission and normal CA125 levels after first-line platinum-based chemotherapy. At baseline, most patients (81%) were diagnosed with FIGO stage III/IV disease and the median age was 62 years old.
They compared overall survival of 265 women who began second-line chemotherapy based solely on an increase in CA125 with that of 264 women with rising CA125 who delayed chemotherapy until symptoms of relapse appeared such as pelvic pain or bloating.
“What was really quite surprising,” Dr. Rustin said, “was that earlier institution of chemotherapy did not induce a longer remission…or improve survival.”
Even though the early treatment group started second-line chemotherapy 4.8 months before the delayed treatment group, overall survival was the same in both arms: 41 months since completion of first-line chemotherapy.
“Women can be reassured,” Dr. Rustin said, “that there is no benefit from early detection of recurrence by routine CA125 measurements. Even if CA125 rises, if they are well, chemotherapy can be delayed until signs or symptoms of tumor recurrence.”
Based on this study, women can be offered two choices in follow-up care — no routine CA125 measurements, but rapid access to CA125 testing as needed, or regular CA125 measurements, Dr. Rustin said.