I found this a helpful way of visualizing the development of cancer and taming our crippling fear of one of the most dreaded diseases. At every milestone of its development Dr. Gilbert Welch clearly notes that the body has the potential to overcome the abnormal growth.
Unfortunately, what Dr. Welch did not put in this diagram (which, however, he does explain very well in other parts of the book) is the fact that having an invasive cancer does not necessarily lead to death from that cancer. For one, the cancer may be nonprogressive or a slow progressing type such that it will never be the cause of death. Or the cancer may even regress without treatment.
Death from the cancer can happen if the cancer is of the aggressive type and if left untreated (if a reliable treatment is in fact available) and metastasizes.