According to an article recently published in the Journal of Clinical Oncology, women with early breast cancer may delay chemotherapy for up to three months without affecting long-term outcomes. However, at three months a delay in chemotherapy is associated with a decreased survival rate.
Early breast cancer refers to cancer that has not spread from the breast or axillary (under the arm) lymph nodes. Standard therapy for early breast cancer often includes surgery, followed by radiation therapy and chemotherapy. Results from a recent study have indicated that delaying radiation therapy for more than three months following surgery may reduce outcomes for patients.
Researchers from British Columbia recently conducted a clinical trial to evaluate the timing of chemotherapy following surgery among women with early breast cancer. This trial included 2,594 women who received initial surgery followed by radiation therapy. The women were then divided into the following four groups to determine optimal timing of chemotherapy: less than four weeks from surgery, four to eight weeks from surgery, eight to 12 weeks from surgery, and 12–24 weeks from surgery.
- When chemotherapy was administered less than four weeks after surgery, relapse-free survival was 74% and overall survival was 84%.
- When chemotherapy was administered four to eight weeks after surgery, relapse-free survival was 79% and overall survival was 85%.
- When chemotherapy was administered eight to 12 weeks after surgery, relapse-free survival was 82% and overall survival was 89%.
- Beyond 12 weeks, however, survival rates began to decline: when chemotherapy was administered 12–24 weeks after surgery, relapse-free survival was reduced to 69% and overall survival to 78%.
The researchers concluded that delaying chemotherapy for up to three months following surgery does not appear to compromise long-term outcomes for patients with early breast cancer. However, delaying treatment with chemotherapy longer than three months appears to decrease survival among these patients.
Patients diagnosed with early-stage breast cancer may wish to speak with their physician regarding their individual risks and benefits associated with optimal timing of their treatment regimen.
Reference: Lohrisch C, Paltiel C, Gelmon K, et al. Impact on survival of time from definitive surgery to initiation of adjuvant chemotherapy for early-stage breast cancer. Journal of Clinical Oncology.2006;24:4888-4894.