Two hundred and fifty stage II-IV gastric cancer patients who should receive neoadjuvant therapy, conversion therapy or palliative chemotherapy will be enrolled in this study. Baseline information of the enrolled patients including medical history, physical examination records and clinical examination records will be collected. Tumor material of those patients will be obtained from gastric endoscopic biopsies or surgical resection. Patient-derived organoids (PDOs) will be established and cultured from gastric cancer tumor specimens. PDOs will then be treated with drugs of the chemotherapeutic regimens for gastric cancer. Organoid size and growth will be monitored before and after the treatment, and dose-response curves will be generated. As for the assessment of clinical outcomes of patients, tumor regression grade (TRG) systems will be used to evaluate tumor histological responses, and treatment responses will also be assessed by biomedical imaging according to the Response Evaluation Criteria in Solid Tumors (RECIST1.1). Consistency between treatment responses in PDO models and clinical outcomes of patients will be assessed by correlation analysis.
Gastric cancer is the fourth leading cause of cancer-related death worldwide. Accurate assessment of the clinical responses to current treatment regimens is key to improving the prognosis and prolonging the survival of patients. In this study, two hundred and fifty patients with gastric cancer who ought to receive neoadjuvant therapy, conversion therapy or palliative chemotherapy will be enrolled, and patient-derived organoids from their tumor biopsies will be used to test the sensitivity of chemotherapy drugs which mainly include 5-fluorouracil, irinotecan, oxaliplatin and paclitaxel.