China is one of the countries with the highest incidence of gastric cancer, and the new cases of gastric cancer account for more than 40% of the world. According to the latest statistics, about 679 thousand new cases of new gastric cancer were found in 2015, about 498 thousand of the deaths and second in mortality. A variety of factors such as irregular diet, Helicobacter pylori infection and genetic factors are important causes of gastric cancer.

Scientific research has proved that cancer is caused by genetic variation in human body. These mutations will lead to cell loss of normal regulation and proliferation, and eventually cause cancer. Targeted drugs can be targeted at killing tumor cells carrying specific gene mutations, which is effective. Therefore, it is considered to be the first choice for multiple cancer patients in advanced cancer. For different patients, the genetic variation carried by them is also varied. This difference leads to the different sensitivity and toxicity of each patient to the same targeted drug.

Precision diagnosis is a prerequisite for precision medical treatment. The idea of molecular typing enables doctors to develop the best treatment plan according to the biomarkers and corresponding clinical conditions of gastric cancer patients, and to find the most potential target drugs and improve the efficiency of anticancer drugs. Specific targeted therapies in gastric cancer include the corresponding treatment for patients with Her2 positive. There are also some new targeted therapies, such as MET, which are still in research and development.

The occurrence of tumor is often accompanied by multiple gene mutations and is heterogeneous. The two generation sequencing technology can achieve multi gene parallel detection, and achieve higher technical sensitivity under the condition of more sample saving than traditional detection methods, so as to restore the panoramic panoramic of cancer more realistically.