Effective. Tumor, also known as cancer in general, is a malignant tumor originating from epithelial tissue, which has biological characteristics such as abnormal cell differentiation and proliferation, metastasis and so on. Pecan skin contains many kinds of polyphenols, such as flavonoids, phenolic acids, polyphenolamides and so on, which can strengthen the function of immune system and improve the body's resistance. Although tumor cells escape the attack of immune cells by inhibiting the function of immune system, polyphenols can enhance the function of immune system and thus play an anti-tumor role.