Neoadjuvant therapy in breast cancer – an update

Traditionally, neoadjuvant systemic therapy (NST) serves as treatment of advanced breast cancer to achieve technical operability by resulting in tumor regression. Nowadays, NST is advantageous in all cases if adjuvant systemic therapy is needed, since the in vivo study of its effect provides possibility for the estimation of prognosis, the treatment may be modifi ed according to the therapeutic response, the systemic therapy starts earlier as compared to adjuvant therapy, and fi nally, it may result in the reduction of surgical and radiotherapeutical radicality. The type of NST should be selected on the basis of tumor features refl ecting treatment sensitivity. In case of chemosensitive cancers, chemotherapy is taxane- and anthracycline-based, and the planned dose should be delivered prior to surgery. In HER2-positive cancers, the addition of an anti-HER2 agent doubles the rate of pathological complete regressions. In hormone-sensitive tumors, the standard neoadjuvant endocrine therapy consists of an aromatase inhibitor (postmenopause), or tamoxifen or an aromatase inhibitor combined with an LHRH analog (premenopause) for 4-8 months that is continued following the surgery in the adjuvant setting. For the early evaluation of the effect of NST, serial tumor biopsy or imaging studies (MRI, PET) seem promising. Sentinel lymph node biopsy around the NST should be practiced with prudence; it may warrant the avoidance of axillary blockdissection in some cases. For the design of radiotherapy, the initial stage and the degree of regression are considered.