The purpose of PET scans like the one I had a few days ago is to detect suspicious activity on the cellular level. When it comes to tumors (i.e. cancer), size doesn’t matter that much. It’s more about genetics.
In a New Yorker article called “The Picture Problem,” Malcolm Gladwell interviewed several experts about the pros and cons of our current approach to early detection.
The danger posed by a tumor is expressed visually. Large is bad; small is better—less likely to have metastasized. But here, too, tumors defy visual intuitions.
According to Donald Berry of the M. D. Anderson Cancer Center in Houston, “we don’t know whether it’s tumor size that drives the metastatic process or whether all you need is a few million cells to start sloughing off to other parts of the body. We do observe that it’s worse to have a bigger tumor. But not amazingly worse. The relationship is not as great as you’d think.”
… scientists discovered that even with tumors in the one-centimeter range…the fate of the cancer seems already to have been set.
At its root, cancer is in the genes. We all produce defective ones but it’s only when they get out of control that tumors sprout and cancer spreads. The best hope until we can find a genetic cure is to make our bodies a hostile environment for cancer through diet and lifestyle.