What is the best timing for chemotherapy after surgery in patients with early-stage breast cancer?

This study looked at the timing of chemotherapy (CT) after surgery in the treatment of early breast cancer (BC). The authors found that CT given within 31 days after surgery may improve survival in patients with triple-negative (TN) BC. 

BC is one of the most common types of cancer found in women. There are multiple types of BC depending on the receptors (proteins) found on cancer cells. TN BC is a form of aggressive BC that has no receptors for hormones (estrogen and/or progesterone) or HER2. It is more difficult to treat. Treatment for early-stage BC usually involves surgery followed by CT to kill any cancer cells that may have been left after surgery. Despite advances being made in treatment for BC, the optimal timing of CT after surgery has not been defined in patients with early-stage BC. 

The study looked at 2003 patients with early-stage BC. All patients were treated with surgery followed by CT. 1102 patients started CT less than 31 days after surgery (group 1). 901 patients started Ct 31 days or more after surgery (group 2). Some patients also received hormonal therapy or radiotherapy. The average length of follow-up was 115 months. 

Overall, there was no difference in disease-free survival (DFS) in both groups. The 5-year DFS rate was 81% for group 1 and 82% for group 2. Overall survival rates at 5 years were also similar between group 1 (89.8%) and group 2 (90.7%).

However, patients with TN BC who received CT within 31 days of surgery were 2.18 times more likely to have a longer overall survival compared to those who had CT after 31 days or more from surgery. The 5 years overall survival rate for patients with TN BC was 89% in group 1 compared to 77% in group 2.

The authors concluded that overall, the timing of CT after surgery did not impact survival. However, in patients with TN BC, CT given within the first 31 days after surgery may improve survival.

This study was based on medical records. Some data regarding the type of BC was missing. This may have affected the results.