Because of its special anatomical structure, local recurrence rate of locally advanced proximal gastric adenocarcinoma is still high after radical operation.

As a local/regional therapy, radiotherapy combined with concurrent chemotherapy can kill local residual tumor cells and reduce the risk of local and regional recurrence.

• Radiation: Adjuvant Chemoradiotherapy
  DT 45Gy/25F/5W, using IMRT technology, synchronous tegio single drug chemotherapy
  Other Name: CRT
• Drug: Adjuvant Chemotherapy
  Oxalis 130mg/m2 intravenous drip on day 1, tegio 80-120 mg daily, twice, half an hour after breakfast and dinner, for 14 consecutive days
  Other Name: CT

• Experimental: Adujvant CT+CRT
  Four to six weeks after D2 radical surgery, adjuvant chemotherapy was initiated with SOX regimen , repeated every three weeks, and adjuvant radiotherapy was started at the end of two cycles of adjuvant chemotherapy , with synchronous tegiol single drug chemotherapy. And the original SOX regimen was continued for 4 cycles after 3-4 weeks of radiotherapy.
  Interventions:

  • Radiation: Adjuvant Chemoradiotherapy
  • Drug: Adjuvant Chemotherapy
• Active Comparator: Adujvant CT
  The adjuvant chemotherapy was started 4-6 weeks after D2 radical operation. The SOX regimen was repeated every 3 weeks for 8 cycles.
  Intervention: Drug: Adjuvant Chemotherapy

Inclusion Criteria:

• Voluntary Participation and Written Signature of Informed Consent.
• Age 18-70, gender unlimited.
• Gross pathology confirmed that the tumor center was within 1 cm to 5 cm of the EGJ line. Histopathologically diagnosed as adenocarcinoma.
• No neoadjuvant therapy.
• Transabdominal standard D2 radical operation was performed and R0 resection was performed. Ascites cytology was negative.
• The pathological stages were IIB, IIIA, IIIB and IIIC.
• There was no intraperitoneal implantation and distant metastasis. CT should be routinely performed to evaluate the tumor bed before radiotherapy. Positron emission tomography (PET-CT) could be accepted to determine whether there was residual or distant metastasis.
• Physical condition score ECOG 0-1.
• No history of serious heart and lung diseases, abnormal hematological examination and immunodeficiency: hemoglobin (Hb) > 9 g/dL; white blood cell (WBC) > 3 x 109/L; neutrophil (ANC) > 1.5 x 109/L; platelet (Pt) > 100 x 109/L; bilirubin < 1.5 times the upper limit of normal value; glutathione transaminase (ALT) & alanine transaminase (AST) = 2.5 times the upper limit of normal value; serum creatinine < 1.5 times the normal value Upper limit.
• No other systemic tumors were found.
• Fertile men or women are willing to take contraceptive measures in the trial.
• The daily energy intake is more than 1500 kcal.

Exclusion Criteria:

• Those who had a history of malignant tumors (except skin basal cell carcinoma, thyroid papillary adenocarcinoma and cervical carcinoma in situ, who survived for more than 3 years after treatment).
• Patients with a history of neoadjuvant radiotherapy and chemotherapy before operation.
• Study participants who participated in other clinical trials within 30 days before treatment.
• Pregnancy, lactation or fertility without contraceptive measures.
• Drug addiction and other adverse drug addiction, long-term alcoholism and AIDS patients.
• Those with uncontrollable infections, seizures, or loss of self-awareness due to mental illness.
• Those with a history of severe allergy or specific constitution.
• Researchers believe that it is not appropriate to participate in this experiment.