Ureteral cancer metastasis to peritoneum is because ureteral cancer is already in advanced stage and tumor metastasis to peritoneum has occurred. Clinically, as long as the tumor is malignant, it will have the possibility of metastasis, so ureteral cancer is very likely to metastasize. Ureteral cancer metastasizing to peritoneum may be because the cancer cells of ureter enter into blood vessels or lymphatic vessels after shedding off from tumor tissues and reach the location of peritoneum with the blood running, forming metastasis. However, even if the cancer cells metastasize, they may not necessarily grow immediately, and it depends on whether the environment is suitable or not, so it is also possible that they may be lurking there and will not carry out the next step of development immediately, and it is generally necessary to find out the metastasis of the cancer lesions through relevant examinations. Therefore, patients with ureteral cancer, especially those in advanced stage, should go to the hospital for regular review regularly in order to detect metastasis at an early stage.