Clinically, most carcinoma in situ can be clinically cured after surgical resection, but regular review is needed. Carcinoma in situ is called pre-invasive cancer or intra-epithelial cancer, which belongs to the very early stage of cancer. In carcinoma in situ, the cancerous lesions are only confined to the basement membrane, with no invasion outside the basement membrane and no distant metastasis. The lesions in this period are small, without obvious clinical symptoms, and after surgical resection, the incidence of recurrence and metastasis of cancer lesions is extremely low. Most patients can achieve clinical cure for their cancer. Although the probability of recurrence and metastasis after surgical resection of adenocarcinoma in situ is very low, patients are still recommended to undergo regular review. Pay attention to light diet, quit smoking and drinking, and exercise moderately in daily life.