According to research presented at the 2013 Alzheimer’s Association International Conference, many types of cancer are associated with a decreased risk of developing Alzheimer disease (AD). This is the second report within a week that reported on a link between cancer and lowered AD risk. This study of 3.5 million veterans age 65 and older found that many cancers reduced the risk of AD from 9% to 51%. The greatest decrease in risk was seen with liver cancer. Melanoma, prostate and colorectal cancers were not associated with a decreased risk. In addition, chemotherapy, but not radiation treatment, for cancer was associated with an additional 20% to 45% decrease in risk. Understanding why cancer and chemotherapy lead to a reduced risk of AD could open up new avenues of research for the prevention and treatment of AD. Please note, information presented at meetings is preliminary and subject to change until published in a peer-reviewed journal.