Everyone has cancer
By middle age, people are riddled with cancer cells:
But knowing more about how tumors develop and sometimes reverse course might help doctors decide which tumors can be left alone and which need to be treated, something that is now not known in most cases.
Cancer cells and precancerous cells are so common that nearly everyone by middle age or old age is riddled with them, said Thea Tlsty, a professor of pathology at the University of California, San Francisco. That was discovered in autopsy studies of people who died of other causes, with no idea that they had cancer cells or precancerous cells. They did not have large tumors or symptoms of cancer. “The really interesting question,” Dr. Tlsty said, “is not so much why do we get cancer as why don’t we get cancer?”
The earlier a cell is in its path toward an aggressive cancer, researchers say, the more likely it is to reverse course. So, for example, cells that are early precursors of cervical cancer are likely to revert. One study found that 60 percent of precancerous cervical cells, found with Pap tests, revert to normal within a year; 90 percent revert within three years.
But if you think about it, it is tough to imagine a model whereby this situation comes about suddenly in middle age. What is more likely is that everyone has cancer cells from a young age. What declines over time is the ability of the body to manage those cancer cells.