Early Chemotherapy for Ovarian Cancer Relapse Based on Serial CA-125 Monitoring does Not Improve Overall Survival or Quality of Life

Early chemotherapy for relapsed ovarian cancer based on serial monitoring of CA-125 levels failed to improve overall survival or quality of life (QOL) compared with delayed therapy according to clinical signs and symptoms of relapse in a large European trial that were presented at ASCO’s Plenary Session.

“Early treatment does not improve survival. In fact, it slightly decreases quality of life, because patients tested early are treated with far more chemotherapy,” stated Gordon Rustin, MD, Mt. Vernon Cancer Center, Middlesex, UK, who presented results. “For the first time, women can be told that even if their CA-125 rises, chemotherapy can be safely delayed until they have signs or symptoms of recurrence. Now women can make informed choices.”

The study, funded by the EORTC and MRC in Europe, enrolled 1442 patients from 59 centers in 10 countries. These women all attained complete remission (CR) on first-line platinum-based chemotherapy and had normal CA-125 measurements at baseline. They were monitored with blood tests for CA-125 every 3 months. Women whose CA-125 levels rose to two times the upper limit of normal (n = 529) were randomized to early treatment (n = 265) or delayed treatment (n = 264). Patients and physicians in the early treatment arm were informed of serial CA-125 results while those in the delayed treatment arm were not.

Non-randomized patients included 421 women with persistent CA-125 levels below two times the upper limit of normal and relapse, 61 women who relapsed, and 213 who relapsed without elevations of CA-125 2 times the upper limit of normal.

Second-line chemotherapy with platinum and a taxane was given to 91 patients (34%) in the early treatment arm and 101 patients (38%) in the delayed treatment arm. Chemotherapy was initiated a median of 0.8 months in the early treatment arm compared with a median of 5.6 months in the delayed arm.

At a median follow-up of 56.9 months, 379 patients were dead and 150 alive. Of the deaths, 364 were disease-related. No difference in survival was observed between the early and delayed treatment arms. The mortality Hazard Ratio was 1.0.

Dr. Rustin said, “Second-line chemotherapy was given 4.8 months earlier in the early treatment arm and third-line chemotherapy was given 4.6 months earlier in this arm. Despite having early chemotherapy, there was no benefit of longer remission from that chemotherapy.”

“The impact of these results on clinical practice is that women with ovarian cancer who respond to first-line chemotherapy can be assured that they will have no benefit from early detection of relapse by routine CA-125 measurements,” he concluded. “Even if CA-125 level rises, chemotherapy can be delayed with the same outcome.”