1. Cancer development - -steps of cell growth -malignant vs. benign -S/S -staging (TNM) 2. Initiation (Steps of cell growth) - -this is an irreversible event -that can lead to cancer development -this can happen due to the presence of carcinogens (cancer causing agents i.e. cxm., physical agents (barret's epithelium in the esophagus), or viruses (HPV) 3. Promotion (Steps of cell growth) - -refers to the enhanced growth of a cell by substances known as promoters -hormones (especially estrogen), body proteins i.e. insulin -causes the malignant cells to divide more rapidly & become a tumor -the period between initiation & growth into a tumor called the latency period-can range from months to yrs. 4. Progression (Steps of cell growth) - -is the continued change of cancer making it more malignant -after a tumor grows to 1cm-it has at least 1 billion cells -once it begins to build its own blood supply, it becomes a health problem -as tumors grow they contain less and less normal cells