Cancer cells generally do not transform into normal cells. Once normal cells are transformed into cancer cells by a combination of internal and external factors, they generally do not reverse into normal cells. If cancer cells are detected early and all cancerous cells can be completely removed through surgery, there may be no cancer cells in the body, which is what people call a cure. Many normal cells in the human body can become cancerous, but most of these cancerous cells will be killed by the body under the action of the normal immune system, while only a few cancerous cells will take root and germinate under the action of the surrounding microenvironment, thus forming tumors. Although cancer cells cannot be transformed into normal cells, some mild and moderate intraepithelial neoplasia have the potential to reverse into normal cells.