"Nearly half of all cancer is related to two things -- tobacco and obesity," said Dr. Jay Brooks, chief of hematology/oncology at Ochsner Health System in Baton Rouge, La. "That's something I don't think people truly grasp." Dr. Neil Hayes, a medical oncologist specializing in lung and head and neck cancers at the University of North Carolina School of Medicine, concurred. "Most of my patients are smokers, so it's rare I see someone truly surprised by the diagnosis. But I don't think they fully think through the risk associated with smoking," he said. Evaluating your risk of cancer, and taking steps to modify those risk factors within your control, could save your life. Smoking is far and away the leading cause of preventable cancer deaths. In the United States, nearly one-third of all cancer deaths -- more than 170,000 Americans -- each year are related to tobacco use, according to the American Cancer Society (ACS). Yet, almost one in four American adults still uses tobacco. And, about 22 percent of teens are still lighting up. Read more at: http://news.yahoo.com/s/hsn/20080329/hl_hsn/youmaybethekeytocancerprevention