On September 20, 2008, “Clinical research on hyperbaric oxygen combined with chemotherapy in the treatment of metastatic gastric cancer”, a key scientific research project in Hefei, which was presided over by Hu Xinglong of the Department of Oncology of our hospital, successfully passed the appraisal. It is understood that gastric cancer is the second most common malignant tumor in the world and the first in China in terms of incidence and mortality. Although the mortality rate of gastric cancer has decreased in recent years, the annual incidence has not decreased. Due to the lack of specificity of gastric cancer symptoms, most gastric cancer patients are in the progressive stage of the disease when they are diagnosed, and the probability of its radical cure is greatly reduced, and in the absence of radical cure, the disease is inevitably classified as metastatic gastric cancer. The treatment of metastatic gastric cancer is currently recognized as a combination of chemotherapy-based treatment. Since gastric cancer is a relatively chemotherapy-sensitive malignancy, how to improve the efficiency, clinical benefit rate and prolong the survival period of chemotherapy is a hot spot and a difficulty in current research. At present, a series of basic and clinical studies on hyperbaric oxygen combined with chemotherapy and radiotherapy for the treatment of malignant tumors have been conducted at home and abroad, indicating that hyperbaric oxygen combined with radiotherapy and chemotherapy for the treatment of malignant tumors is one of the indications for hyperbaric oxygen therapy. However, hyperbaric oxygen has not been well utilized in the treatment of tumors, especially the clinical research on hyperbaric oxygen combined with chemotherapy for metastatic gastric cancer has not been reported in China. Since the establishment of hyperbaric oxygen therapy center in our hospital in 2004, we started to pay attention to the research progress of hyperbaric oxygen combined with chemotherapy in the treatment of malignant tumors, and after reading and summarizing a lot of literature, we proposed the research of this topic and established the project in 2005, which became a key scientific research topic of Hefei Municipal Science Committee. In this study, 30 cases of metastatic gastric cancer (stage IIIb-IV) were treated with hyperbaric oxygen combined with chemotherapy, and 30 cases were controlled with chemotherapy alone group, and the efficacy and toxic side effects, quality of life were observed to explore the value of its clinical application and related mechanisms. The results showed that hyperbaric oxygen combined with chemotherapy could prolong the lesion-free progression time and median survival of patients caused by TTP, reduce some toxic side effects of chemotherapy, and improve patients’ tolerance of chemotherapy. The appraisal committee invited famous domestic experts as judges: Professor Zhu Jinshui from the Sixth People’s Hospital of Shanghai Jiaotong University as the chairman of the appraisal committee, researcher Huang Lianshuai from Anhui Provincial Department of Science and Technology as the deputy chairman, and seven experts including Professor Wu Jianxin from Xinhua Hospital of Shanghai Second Medical University, Professor Zhang Hongyan and Professor Hu Changlu from Anhui Provincial Hospital, Professor Yang Lin and Professor Pan Yueyin from An Medical College. The members of the appraisal committee comprehensively and carefully reviewed the reports and listened to the report of the subject group, reviewed the relevant information, and gave a high evaluation after questioning and discussion. They unanimously agreed that this project is the first one in China to adopt hyperbaric oxygen combined with chemotherapy for metastatic gastric cancer (stage IIIb-IV), which is closely integrated with the clinic, with novel topic, reasonable design, detailed data, reasonable statistical methods, reliable results and correct conclusions. We suggest that the group should continue to increase the number of samples, accumulate clinical data, and conduct further in-depth research. The results of the study are reasonable.