[Pathological evaluation and grading for neoadjuvant therapy]

In Japan, the pathological grading of pre-operative neo-adjuvant therapy for gastric cancer is conducted based on the criterion recommended in the Japanese Classification of Gastric Carcinoma. This pathological grading system has been developed from the classic system proposed by Drs. Oboshi and Shimosao. With this grading system, based on chemotherapy gastric cancer specimens are to be divided into 4 categories based on the ratio of the remaining tumor area against the tumor burden, which is a different method from the RECIST guideline, commonly used in clinical settings. Thus, it will be important for clinicians to understand the basis of this pathological grading system for neoadjuvant therapy, and to properly use it for further treatment of cancer patients.