Issues involved in research into the neoadjuvant treatment of breast cancer.

Randomized studies have failed to find convincing evidence that neo-adjuvant chemotherapy results in improved overall survival. This may be related to limited efficacy of the regimens used. A sequence of an anthracycline-based primary chemotherapy followed by docetaxel has shown promising results which are briefly discussed. The assessment of the efficacy of neoadjuvant therapy should be based on the evaluation of pathological response and a simple, reproducible method of grading differential response would be of great value. Positive identification of tumor stroma is essential in defining pathological complete response (pCR). This paper presents a grading scheme based purely on microscopic assessment which classifies patients into five groups with significantly different disease-free and overall survival. A system dividing patients into only two groups, i.e. those with pCR or those with any evidence of invasive tumor, may lose information of prognostic value. Assessing the response of metastatic disease in the lymph nodes, as well as response of the primary tumor, may further refine our ability to identify those patients likely to gain most from neoadjuvant chemotherapy.