Vietnam veterans have struggled to deal with PTSD and other health challenges in the nearly 50 years since they served overseas.

Following the results of a Department of Veterans Affairs study, a link between cases of a rare bile duct cancer and a parasite that gets into the body via raw or undercooked fish may have been found.

Reporting by the Associated Press found that 700 veterans have been diagnosed with the cholangiocarcinoma over the past 15 years.

To learn more about the disease — and the parasite — I turn to Dr. Paul Brindley. He is director of the Brindley Lab at the George Washington School of Medicine and Health Sciences, and he focuses on neglected tropical diseases and associated cancers.