The formation of endometrial cancer may take several years to decades, and the exact time cannot be determined because of individual differences, cancer types, lifestyles and other related factors. For patients with type I endometrial cancer, it is mostly related to long-term estrogen over-stimulation and lack of progesterone, and the disease develops into cancer gradually, and due to the current advanced diagnostic and treatment technology, usually when women have manifestations such as thickening of endometrial lining, they will be actively intervened with medication or surgery under the guidance of doctors, so the development of cancer will take a longer period of time. For patients with type I endometrial cancer, the cause of the disease is still unclear, and it is mostly related to gene mutation, so when the patient has a combination of gene mutation, there is a possibility of malignant transformation, so the time needed is generally shorter and there is a great individual difference. For patients who are found to have endometrial thickening and endometrial polyps, it is recommended that they go to the gynecology department of a regular hospital, and improve hysteroscopy and pathological examination if necessary, in order to exclude or detect malignant lesions early, and then treat them under the guidance of the doctor as soon as possible.