Clinicopathological Features of Tumors as Predictors of the Efficacy of Primary Neoadjuvant Chemotherapy for Operable Breast Cancer

Neoadjuvant chemotherapy (NC) is standard therapy for patients with locally advanced breast cancer and is increasingly used for early-stage operable disease. Clinical and pathological responses are important prognostic parameters for NC, which aims to achieve a pathological complete response or tumor reduction to reduce the volume of subsequent breast resection. Clinicopathological markers that predict patient response to NC are needed to individualize treatment. From 1998 to 2006, 368 patients with primary breast cancer underwent curative surgical treatment after NC (anthracycline and/or taxane without trastuzumab). We retrospectively evaluated the clinicopathological features and classification of the tumors using computed tomography (CT) before NC and analyzed the correlation with the pathological complete response (pCR) and reduction of tumor size after treatment. The overall response and pCR rates in these patients were 86% and 17%, respectively. In multivariate analysis, classification as a scirrhous-type tumor was an independent predictor of reduced likelihood of pCR (p = 0.0115; odds ratio 0.21). For tumor reduction, histological grade 3 (p = 0.0002; odds ratio 3.3) and localized tumors identified by using CT imaging (p = 0.0126; odds ratio 2.4) were independent predictors in multivariate analysis. In this study, NC often did not result in pCR for breast cancers classified as scirrhous. Furthermore, tumor type classification using CT imaging and histological grading was effective to predict tumor reduction in response to NC that included an anthracycline and/or a taxane.