Transarterial Neoadjuvant Chemotherapy vs.Traditional Intravenous Chemotherapy For Locally Advanced Gastric Cancer With SOX+PD-1 (TACTIC)

Transarterial Neoadjuvant Chemotherapy vs.Traditional Intravenous Chemotherapy For Locally Advanced Gastric Cancer With SOX+PD-1

A Multicenter, Randomized, Controlled Study of S-1 Combined With Oxaliplatin by Arterial Infusion Plus PD-1 Antibody Versus Conventional SOX Chemotherapy Plus PD-1 Antibody for Locally Advanced Gastric Cancer

SOX regimen, consisting of oral S-1 and intravenous oxaliplatin, is the preferred regimen for perioperative chemotherapy for gastric cancer. The goal of this clinical trial is to compare the efficacy and safety between S-1 combined with oxaliplatin by arterial infusion, as neoadjuvant chemotherapy, and conventional SOX regimen, in locally advanced gastric cancer. The main question it aims to answer is: whether arterially infused oxaliplatin plus S-1 has the potential to be a better neoadjuvant option for patients with locally advanced gastric cancer. Participants will be randomised, and receive: 3 cycles of conventional SOX chemotherapy plus PD-1 antibody or arterial infused oxaliplatin plus S-1 and PD-1 antibody, as neoadjuvant chemotherapy; Adequate gastric resection along with D2 lymph node dissection; 3 cycles adjuvant chemotherapy using SOX regimen plus PD-1 antibody. Administration of S-1 regularly till 1 year after surgery. Researchers will compare Major pathological response rate (MPR) ，pathologic complete response rate（pCR）,the 2-year overall survival (OS) rates, 2-year disease free survival (DFS), R0 resection rates, and adverse events, to see if the modified perioperative chemotherapy improve the prognosis of patients with locally advanced gastric cancer.

3 cycles of neoadjuvant chemotherapy: Oxaliplatin arterial infusion+S-1 3 cycles of immunotherapy: sintilimab surgery and 3 cycles of adjuvant chemotherapy using SOX regimen plus sintilimab. S-1 administration till 1 year after surgery

3 cycles of neoadjuvant chemotherapy: SOX regimen 3 cycles of immunotherapy: sintilimab surgery and 3 cycles of adjuvant chemotherapy using SOX regimen plus sintilimab. S-1 administration till 1 year after surgery

All patients, whose lesions are resectable and medically operable after 3 cycles neoadjuvant chemotherapy, will receive gastrectomy plus D2 lymph node dissection.

3 cycles of SOX adjuvant chemotherapy every 21 days after surgery in both groups. Sequential S-1 chemotherapy every 21 days till 1 year postoperation.

The percentage of people who has less than or equal to 10% residual viable tumor after neoadjuvant therapy.

The percentage of individuals in this study who are free of the signs and symptoms of gastric cancer at 2 years after treatment

The percentage of individuals in this study who are alive two years after their diagnosis or the start of treatment.

Inclusion Criteria: Eastern Cooperative Oncology Group(ECOG) score 0-1 Ambulatory males or females, aged 18-75 years Histologically or cytologically confirmed adenocarcinoma of the stomach or gastroesophageal junction (Siewert type II or III) Locally advanced gastric carcinoma (cT3N2-3M0, cT4aN1-3M0, cT4bNanyM0, American Joint Committee on Cancer (AJCC) TNM staging system 8th edition) Life expectancy more than 3 months Give written informed consent, with the understanding that the patient has the right to withdraw from the study at any time, without prejudice. Normal hepatic, renal, and bone marrow function (ALT/AST<2.5 fold of upper limit value;Tbil<1.5mg/dl, Cr<1.5 fold of upper limit value; White Blood Cell count≥3 × 10^9/L, ANC ≥ 1.5 × 10^9/L,PLT≥ 80 × 10^9/L,Hb ≥ 90 g/L). Exclusion Criteria: Patients can not bear surgical procedure. Pregnant or lactating women. HER2 overexpression(+++) confirmed by immunohistochemistry. Previous cytotoxic chemotherapy, radiotherapy or immunotherapy. History of another malignancy within the last five years. History of uncontrolled seizures, central nervous system disorders or psychiatric disability judged by the Investigator to be clinically significant precluding informed consent or interfering with compliance for oral drug intake. Clinically significant (i.e. active) cardiac disease e.g. symptomatic coronary artery disease, New York Heart Association (NYHA) grade II or greater congestive heart failure or serious cardiac arrhythmia requiring medication or myocardial infarction within the last 12 months. History of dysphagia, complete or partial gastrointestinal obstruction, active gastrointestinal bleeding and gastrointestinal perforation; Organ allografts requiring immunosuppressive therapy. Serious uncontrolled intercurrent infections or other serious uncontrolled concomitant disease. Moderate or severe renal impairment: serum creatinine > 1.5 x upper limit of normal (ULN). Hypersensitivity to any drug of the study regimen. With abdominal cavity implantation metastasis or distant metastasis. Unwilling or unable to comply with the protocol for the duration of the study.