Neoadjuvant Versus Adjuvant Chemotherapy in Early Breast Cancer
The use of neoadjuvant chemotherapy appears to be associated with a higher local recurrence risk than the same chemotherapy given postoperatively after breast-conserving surgery, according to a meta-analysis reported in The Lancet Oncology by the Early Breast Cancer Trialists’ Collaborative Group.
The meta-analysis identified 4,756 women with early breast cancer randomized to receive either neoadjuvant chemotherapy or the same chemotherapy given postoperatively. Patients from 10 randomized trials were included, with women entering the trials between 1983 and 2002 and a median follow-up of 9 years. Most of the women (about 80%) received anthracycline-based chemotherapy. The other chemotherapy agents included mitoxantrone, methotrexate, mitomycin, cyclophosphamide, and fluorouracil.
More than two-thirds of women allocated neoadjuvant chemotherapy had a complete or partial clinical response. Neoadjuvant chemotherapy was associated with a statistically significant increase in local recurrence compared with adjuvant chemotherapy, with a 15-year local recurrence rate of 21.4% versus 15.9%, respectively. Patients receiving neoadjuvant chemotherapy had an increased frequency of breast-conserving therapy (65% vs. 49%).
No significant difference was found in distant recurrence, breast cancer mortality, or death from any cause. “Strategies to mitigate the increased local recurrence after breast-conserving therapy in tumours downsized by [neoadjuvant chemotherapy] should be considered (eg, careful tumour localisation, detailed pathological assessment, and appropriate radiotherapy),” noted the researchers.