| To summarize, there are four major phases of tumor | | | | The invasive phase can happen rapidly, requiring only |
| formation. Each phase can take years to complete. | | | | a few months. However, in some cases it may take |
| The first one alone usually takes anywhere from 15 | | | | up to five years. This phase is dependent on the |
| to 30 years. | | | | ability of the tumor to invoke nearby blood vessels |
| The first phase occurs when normal cells mutate into | | | | to grow toward it and provide it with nutrients - |
| tumor cells and begin dividing out-of-control. This may | | | | commonly referred to as angiogenesis. |
| take place over successive generations of cells. | | | | Metastasis, or dissemination to other tissues if the |
| When just the right mutations occur, the cells will | | | | final phase. This phase has the same time period as |
| divide and grow to a small tumor. | | | | the invasive phase, ranging from a few months to |
| The second phase is called Carcinoma in situ. This | | | | five years. |
| phase is classified by the presence of a cancerous | | | | At each phase, the cancer can either progress |
| tumor that has not yet invaded other tissues. This | | | | further or altogether diminish. If you add each phase |
| phase usually lasts between 5-10 years and is limited | | | | up, the average for the cell mutating events and |
| by the nutrient flow to the tumor. If blood vessels | | | | cancer diagnosis is 20-50 years apart. This is why |
| can be induced to grow into the tumor | | | | cancer mostly affects older people. Actually, half of |
| (angiogenesis), the tumor will progress to the next | | | | all cancers are diagnosed after the age of 65. |
| phase, called the invasive stage. | | | | |