This legislation mandates the Department of Veterans Affairs (VA) to initiate an epidemiological study within 120 days of enactment, in collaboration with the Centers for Disease Control and Prevention. The study will investigate the prevalence of cholangiocarcinoma , a rare liver cancer, among veterans who served in the Vietnam theater of operations during the Vietnam era, utilizing data from the VA Central Cancer Registry and the National Program of Cancer Registries. It aims to compare incidence rates in these veterans against the general U.S. population and identify percentages by various demographic characteristics such as age, gender, race, ethnicity, and geographic location at diagnosis. Following the study's completion, the VA must submit an initial report to Congress within one year, detailing the results and proposing administrative or legislative actions to address identified issues. The VA is also tasked with continuously tracking the prevalence of cholangiocarcinoma in these veterans and providing periodic follow-up reports to Congress with updated information. Separately, the bill includes a provision to amend title 38, United States Code, extending a certain limitation on pension payments from November 30, 2031, to December 31, 2031.