ACS：2026年美国癌症数据与趋势报告（英文版）

What Is Cancer? Cancer is a group of diseases characterized by the uncontrolled growth and spread of abnormal cells that can result in death if untreated. The cause of most cancers is unknown, but certain lifestyle factors and inherited genetic mutations can increase risk, either by acting alone or in combination, to initiate and/or promote cancer growth. Can Cancer Be Prevented? Excluding non-melanoma skin cancer, at least 40% of newly diagnosed cancers in US adults — about 850,000 cases in