Phenacetin, and products containing phenacetin, have been shown in an animal model to have the side effect and after-effect of carcinogenesis. In humans, many case reports have implicated products containing phenacetin in urothelial neoplasms, especially urothelial carcinoma of the renal pelvis. Phenacetin is classified by the International Agency for Research on Cancer (IARC) as carcinogenic to humans. In one prospective series, phenacetin was associated with an increased risk of death due to urologic or renal diseases, death due to cancers, and death due to cardiovascular diseases.