Efficacy and Survival Analysis of Perioperative Treatment of Locally Advanced Gastric or Gastroesophageal Junction Cancer

This study is a single-center, retrospective cohort study. The purpose is to evaluate different perioperative treatment options on the efficacy and survival prognosis of locally advanced GC/GEJC, clarify whether the tumor regression grade can influence survival of patients using neoadjuvant therapy. Moreover, we aim to explore the clinical and pathological characteristics that will affect the long-term survival benefit of patients who underwent perioperative treatment.

Inclusion Criteria: * (1) Pathologically diagnosed as gastric adenocarcinoma or esophageal-gastric junction adenocarcinoma, and has not received any anti-tumor treatment before (such as surgery, radiotherapy, chemotherapy, targeted therapy, immunotherapy, etc.) * (2) cT3-4N+M0 (according to AJCC version 8 stage) confirmed as resectable by CT or MRI. * (3) Patients who underwent adjuvant therapy before surgery. * (4) After neoadjuvant therapy , radical resection was performed at the Cancer Hospital of the Chinese Academy of Medical Sciences. * (5) Patients who have complete clinical, pathological and imaging data. Exclusion Criteria: * (1) It is known that peritoneal metastasis or peritoneal irrigation solution cytology is positive (CY1P0) or there is distant metastasis (according to the 8th edition of AJCC). * (2) There are unresectable factors, including irresectable tumor causes or surgical contraindications that are irresectable or refuse surgery. * (3) Those who have suffered from other malignant tumors within 5 years or at the same time, except for cured skin basal cell carcinoma and cervical cancer in situ and breast cancer in situ. * (4) Those who have had radiotherapy, interventional treatment and other local therapists before surgery. * (5) Patients whose key diagnosis and treatment information records were missing.