An American Cancer Society study has found that mortality rates for African-American and Caucasian patients with oral cavity and pharynx can¬cer decreased between 1993 and 2007, particularly among those with at least a high school education. Mortality rates increased among Caucasian men with less than a high school education. Researchers suggest that their observed differences may be explained by the prevalence of smoking and risky sexual behaviors among the different educational attainment populations.