A Study to Confirm the Accuracy of Locally Advanced Gastric Cancer Diagnosis

With the introducing of neoadjuvant therapy, it becomes ever more important to evaluate the preoperative TNM (cTNM) stage accurately facilitating preoperative treatment as well as the adjuvant therapy. At present, the recommendation of neoadjuvant chemotherapy varies among guidelines especially between eastern and western countries. According to the updated Japanese gastric cancer treatment guidelines (ver.5), neoadjuvant chemotherapy is the recommended standard procedure for patients with cT2-4 stages. However, the acknowledgement of preoperative therapy accompanied by the higher risk of overtreatment. As mentioned in JCOG1302-A, the overall precision rate in cT staging is 38.8%. Patients diagnosed with pI stages postoperatively account for 6.5% in cT3-4N+ treatment indicating more likely to avoiding the overtreatment comparing to patients with other cT stages. Inspired by JCOG1302-A, this multicentre study prospectively collect data in preoperative TNM staging assessment using CT(computed tomography, CT) scan and the postoperative TNM (pTNM) staging according to histopathologically examination. By analyzing the accordance between the cTNM and pTNM, this study aims to evaluate the current accuracy of the cTNM staging in china, verifying the proportion of pI stages less than 5% in cIII stage diagnosis patients, learning the overtreating rate in neoadjuvant chemotherapy in China and furthermore, to discover the scope of beneficiaries for neoadjuvant chemotherapy.