Earlier this winter, I met an investment banker who was diagnosed with a brain tumor five years ago. He's a managing director at a top Wall Street firm, and I was put in touch with him through a colleague who knew I was writing a story about the potential dangers of cell-phone radiation. He agreed to talk with me only if his name wasn't used, so I'll call him Jim. He explained that the tumor was located just behind his right ear and was not immediately fatal—the five-year survival rate is about 70 percent. He was 35 years old at the time of his diagnosis and immediately suspected it was the result of his intense cell-phone usage.