乳腺癌新辅助化疗是乳腺癌标准化治疗方法之一，因此，新辅助治疗后的病理评估以及评估的标准化非常重要。不同病理评估标准的主要区别在于pCR的定义不同。现阶段一般把ypT₀/is ypN₀定义为pCR，即化疗后乳腺内可残留DCIS，但腋窝淋巴结内无癌细胞残留。笔者将着重介绍日本乳腺癌学会所采用的病理评估标准，并把该标准与美国MD Anderson癌症中心的残余肿瘤量(Residual Cancer Burden)系统、英国的Millar和Payne法，以及天津市肿瘤医院推荐的病理评估标准等进行比较。大量的临床研究表明，新辅助化疗后乳腺癌pCR者相比非pCR者，其DFS率和OS率均有明显提高。但是，pCR对于各种乳腺癌亚型的意义不尽相同，而pCR可能不是新辅助化疗的唯一预测因子。

Neoadjuvant chemotherapy is one of the standardized treatment methods for breast cancer. Pathological assessment and standardized evaluation after neoadjuvant therapy are very important. The main differences between the different criteria of pathological assessments are their definitions of pathologic complete response (pCR), which is currently generally defined as ypT₀/is ypN₀, that is, residual ductal carcinoma in situ in the breast after chemotherapy, without residual cancer cells in the axillary lymph nodes. This paper introduces the histological response criteria of the Japanese Breast Cancer Society and compares it with the Residual Cancer Burden system of MD Anderson Cancer Center, the Millar and Payne method of the United Kingdom, and the pathologic evaluation standard recommended by Tianjin Cancer Hospital. A large number of clinical studies show that the DFS and OS of breast cancer patients with pCR are significantly higher than those of non-pCR patients after neoadjuvant chemotherapy. However, pCR has different meanings in different breast cancer subtypes and pCR may not be the only predictor in neoadjuvant chemotherapy.