Gastrointestinal stromal tumor is the most common mesenchymal tumor in gastrointestinal tract, accounting for 1% ~ 3% of gastrointestinal malignant tumor, and it is more common in middle-aged and elderly people. Gastrointestinal stromal tumors mostly occur in the stomach and small intestine, followed by rectum and esophagus. So, what is the cause of this malignant tumor? The etiology of gastrointestinal stromal tumors is now developed by molecular biology technology. Since 1998, people have been studying it more and more deeply. It is now believed that the origin of gastrointestinal stromal tumors is caused by mutation of C-kit gene. Due to the mutation of C-kit gene, the protein CD 1 17 expressed by C-kit gene was greatly amplified, which caused the neoplastic changes and infinite proliferation of gastric interstitial tissue and formed tumors. It turns out that the occurrence of gastrointestinal stromal tumors is related to gene mutation, so what causes gene mutation in human body? One of the common causes of gene mutation is the defect or variation of chromosomes in our own bodies, and there is also an environmental factor. Because all our xx cases occurred in adults aged 40 to 80, some diseases were discovered very early due to gene mutation, which may have occurred in their twenties and thirties, but why this disease is so late is also a category of current research. Gene mutation in human body is the main cause of gastrointestinal stromal tumors, and some environmental pathogenic factors such as viruses, radiation, pollutants and chemicals can often induce gastrointestinal stromal tumors. Therefore, we should pay more attention to the related factors that may cause gastrointestinal stromal tumors in our lives, stay away from these factors and protect our bodies from harm. All right, everybody's finished.