NEW YORK (Reuters) - Deaths from mouth and throat cancer have dropped since the early 1990s, according to a new study but only among people with at least a high school education. Researchers said that may be due to higher rates of smoking and other oral cancer risks among less educated, poorer Americans, and because theyre also less likely to have access to timely health care. Similar trends have been shown in rates of death from lung and breast cancers, for example, they added. We have a lot more to do in terms of (the fact that) socioeconomic status probably is a really significant factor in mortality from oral and oropharyngeal cancers, said Dr. Joseph Califano, who studies those cancers at the Johns Hopkins University School of Medicine in Baltimore but wasnt involved in the new research.