Adjuvant chemotherapy for breast cancer after a delay from surgery: should it be given? – pro
Should adjuvant chemotherapy be given after a delay beyond 2-3 months? The problem is that there are no studies of adjuvant therapy after such a delay, and there are theoretical reasons why it may not work after such a delay. There is literature documenting poorer outcomes form a delay beyond 91 days, and there is no literature to support subjecting patients to risk fo chemo when a benefit cannot be assured. A meta-analysis by Zhan et al reveals that OS decreases by 13% and DFS decrease by 14% for every four weeks that AC was delayed. Yu et al. reported a similar result: OS decreases by15% and DFS decreases by 16% for every four-week delay in the initiation of AC. Considering that the overall benefit of adjuvant chemotherapy is about 30%, it is likely that the delay of this magnitude provides no benefit and can only be harmful.
Chavez-MacGregor M et al, Delayed Initiation of Adjuvant Chemotherapy Among Patients With Breast Cancer. JAMA Oncol. 2016 Mar;2(3):322-9.
Zhan KD, Huang S, Zhang JX, Liu GY, Shao ZM. Association between delayed initiation of adjuvant CMF or anthracycline-based chemotherapy and survival in breast cancer: a systematic review and meta-analysis. BMC Cancer. 2013;13:240.
Yu KD, Huang S, Zhang JX, Liu GY, Shao ZM. Association between delayed initiation of adjuvant CMF or anthracycline-based chemotherapy and survival in breast cancer: a systematic review and meta-analysis. BMC Cancer. 2013;13:240.