Noninvasive nodal restaging in clinically node positive breast cancer patients after neoadjuvant systemic therapy: A systematic review

Objective: To provide a systematic review of studies comparing the diagnostic performance of noninvasive techniques and axillary lymph node dissection in the identification of initially node positive patients with pathological complete response of axillary lymph nodes to neoadjuvant systemic therapy. Methods: PubMed and Embase databases were searched until May 21st, 2014. First, duplicate studies were eliminated. Next, study abstracts were read by two readers to assess eligibility. Studies were selected based on predefined inclusion criteria. Of these, data extraction was performed by two readers independently. Results: Of the 987 abstracts that were considered for inclusion, four were eligible for final analysis, which included a total of 572 patients. The diagnostic performance of clinical examination, axillary ultrasound, breast MRI, whole body F-18-FDG PET-CT, and a prediction model to identify patients with pathological complete response were investigated. Studies were often limited by small sample size. Furthermore, systemic therapy regimens and definitions of clinical and pathological complete response were variable, refraining further pooling of data. The reported positive predictive value of different techniques to identify patients with axillary pathological complete response after neoadjuvant systemic therapy varied between 40% and 100%. Conclusion: At present, there is no accurate noninvasive restaging technique able to identify patients with complete axillary response after neoadjuvant systemic therapy.