Carcinogenesis or oncogenesis or tumorigenesis is the actual formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by a progression of changes at the cellular, genetic, and epigenetic level that ultimately reprogram a cell to undergo uncontrolled cell division, thereby forming a malignant mass.

Carcinogenesis or oncogenesis or tumorigenesis is the actual formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by a progression of changes at the cellular, genetic, and epigenetic level that ultimately reprogram a cell to undergo uncontrolled cell division, thereby forming a malignant mass.