Results of the SWOG S0500 Trial

Clinical Pearls

Brian Leyland-Jones, MBBS, PhD, director of Edith Sanford Breast Cancer Research, discusses the results of the SWOG S0500 trial, which looked at circulating tumor cell (CTC) levels in patients with metastatic breast cancer. Results of the trial were presented at the 2013 San Antonio Breast Cancer Symposium.

• The trial set out to determine whether CTC levels could be used to guide the frontline treatment of metastatic breast cancer
• It was hypothesized that those patients who maintained a high level of CTCs would do badly
• Patients with low CTC levels before and after chemotherapy did best
• Patients with elevated CTC levels before chemotherapy but lower levels after chemotherapy did moderately well
• Patients with elevated CTC levels before and after chemotherapy did poorly
• This trial demonstrated how dramatic the differences were in prognosis amongst the three groups