TUESDAY, Oct. 3, 2006 (HealthDay News) -- Women with early-stage breast cancer may safely wait up to 12 weeks after cancer surgery before they begin chemotherapy, a new study shows.
However, waiting any longer than that increases the risk of cancer recurrence and reduces overall survival by 60 percent, a Canadian team concluded.
The findings were published Monday in the online edition of the Journal of Clinical Oncology.
For this study, researchers in the province of British Columbia analyzed the records of nearly 2,600 breast cancer patients.
"Our findings can reassure women with early-stage breast cancer that it is okay to take some time before their start chemotherapy to gather information and be actively involved in treatment decision-making. These steps have been shown to reduce anxiety and depression associated with breast cancer," study lead author Dr. Caroline Lohrisch, a medical oncologist with the BC Cancer Agency, said in a prepared statement.
"However, to achieve the full benefit of chemotherapy, patients should not delay further, and should ensure that they start treatment within three months of surgery," she added.
The women in this study received chemotherapy after surgery for stage I and II breast cancer between 1989 and 1998. Among women who started chemotherapy within four weeks of surgery, 84 percent were alive five years after their breast cancer diagnosis. Survival rates were similar for women who began chemotherapy four to eight weeks (85 percent) and eight to 12 weeks (89 percent) after surgery.
But the study found that five-year survival dropped to 78 percent among women who didn't start chemotherapy until more than 12 weeks after breast cancer surgery. These women also had a higher rate of cancer recurrence (31 percent) than women who started chemotherapy within 12 weeks (18 percent to 26 percent).
The U.S. National Cancer Institute has more about breast cancer treatment.