Stephen Hawking tells us that all life started from one cell. I figure that, if that cell had not mutated, there would be no life on earth.
Therefore, is cancer just nature continuing its process - at our expense?
Each of us thinks of ourselves as a unit. In fact we are what STAR TREK called, big "bags of mostly water."
And we contain billions of cells all doing their own thing while we are totally oblivious to is going on.