It is not possible to determine whether a cancer is early or advanced. Generally, there are early-stage cases of moderately differentiated adenocarcinoma, but there are also some cancers that are in the middle or late stage when detected, and the size of the tumor, the presence or absence of surrounding tissue infiltration and distant metastasis should be taken into consideration. The degree of cell differentiation is divided into highly differentiated, moderately differentiated, poorly differentiated and undifferentiated cancers. The higher the degree of differentiation, the lower the malignancy. Intermediate differentiated adenocarcinoma is in the middle and may be more malignant than highly differentiated cancer, but it will be better than the low differentiated and undifferentiated cases. In this case, early-stage patients can still hope to be cured by surgery, and post-operative treatment can be combined with chemotherapy, radiotherapy and targeted drugs, and the stage can be more clearly determined according to post-operative pathology.