Mutations

I've written many times about how the relationship between the early detection of cancer and decreased mortality from cancer is not nearly as straightforward as the average person—even the average doctor—thinks, the first time being in the very first year of this blog's existence. Since then, the complexities and overpromising of various screening modalities designed to detect disease at an early, asymptomatic phase have become a relatively frequent topic on this blog. Even more than ten years ago, I noted that screening MRI for breast cancer and whole body CT scans intended to detect other…
On Pharyngula, PZ Myers says that cancer, unlike an infectious bacterium or virus, is not the product of millions of years of evolution. Instead, PZ writes, “Cancer misuses and perverts existing processes in your cells to send them out of control.” But what causes cancer? Well, it happens about 20,000 times a day in your body. Luckily, it is almost always repaired. It is the mutation of DNA during cell division. Just one base out of place, and suddenly the gene that made a protein to tightly regulate cell division is making a protein that encourages the cell to divide continually. Depending…