Parasitic Worms Cause Bile Duct Cancer

A parasitic liver fluke is thought to be associated with cancer of the bile duct, which is sometimes linked to eating uncooked freshwater fish.

In Thailand, health authorities are screening people infested with the worms for signs of the cancer especially as nearly all cases of cholangiocarcinoma develop in individuals with this infection.

The link between the cancer and the infection is now being investigated at the George Washington University School of Medicine and Health Sciences (Washington DC, USA) which has just been awarded a five year, US$500,000-per-year grant from the US National Cancer Institute (NCI; Bethesda, MA, USA). The grant will support research into the development of proteomic biomarkers for Opisthorchis viverrini induced cholangiocarcinoma.

The scientists will use a quantitative proteomics approach to scan tumor tissues and matched plasma patients with cholangiocarcinoma to identify a suite of candidate biomarkers proximal to the disease site. Any potential biomarkers identified during the analysis of tumor tissue will be verified in the plasma of healthy individuals who are at risk for bile duct cancer from O. viverrini infection.

The global epicenter of cholangiocarcinoma is the region along the Chi River basin in Northeast Thailand, where infection with O. viverrini is endemic. The parasite is also endemic in Laos, Vietnam, and Cambodia, but it is difficult study cancer incidence in those countries. In Thailand, everyone above 30 years of age will get an annual stool examination to screen for fluke eggs. Those who are infected will be treated with drugs. O. viverrini is a food-borne parasite that is believed to infect more than 40 million people, primarily in Southeast Asia. Raw fish is the immediate host for the parasite and is a staple of the diet in that region.

Jeffrey M. Bethony, PhD, an associate professor of microbiology, said, "Bile duct cancer is associated with a late presentation, and there is no effective chemotherapy to treat the disease. Therefore, in addition to intervention strategies that focus on preventing or treating liver fluke infection, there is a need to identify biomarkers that can be measured early and in accessible samples.”

Related Links:
George Washington University
US National Cancer Institute