Cancer is mainly classified into stage 0-4 according to pathological stage. stage 0 may be in situ cancer, stage 1 is early stage cancer, stage 2 and 3 are intermediate stage and stage 4 is advanced stage, the earlier the stage, the better the treatment effect may be, however, it also depends on the follow-up treatment. stage 0, which is in situ cancer, can be removed simply by surgical radical excision. stage 1 is the same, if there is no infiltrative manifestation after surgical radical excision, there is no need to do radiotherapy is not needed if there is no infiltration after surgery. If there is infiltration, postoperative adjuvant chemotherapy is required as in stage 2. stage 3, most of which may not be operable, if operable, may require adjuvant radiotherapy as the postoperative pathology indicates more lymph node metastases. stage 4, which is advanced, may have widespread metastases, which cannot be operated and can be treated with palliative radiotherapy or targeted drug therapy.