After operation

radiotherapy and chemotherapy

the cancer is eliminated

but recurrence and metastasis can still occur. It has characteristics of insidious onset and poor prognosis

which is consistent with characteristics of "lingering pathogen hidden internally" in traditional Chinese medicine. From clinical practice

it is believed that healthy qi deficiency is the cause of "lingering pathogens hidden internally" and "onset due to hidden pathogens"

and emotional disorder is promoting factor in "reignition" of hidden pathogens. Clinical treatment of traditional Chinese medicine in postoperative cancer recurrence and metastasis should be focused on prevention before disease. "Clearing" and "expelling" should be applied for "eliminating pathogens". Supporting healthy qi is applied for reinforcement and elimination in combination. It provides theoretical support for basic research and clinical application of traditional Chinese medicine in preventing and treating postoperative recurrence and metastasis of cancer.