Friday, July 13, 2007

Worms in Asian Fish Linked to Rare Liver Cancer

July 13, 2007
By Margie Mason/AP Writer/Hanoi

Worms found in freshwater fish in Southeast Asia can lead to a rare type of liver cancer in people who eat raw fish, with o­ne province in Thailand logging the world's highest rate of new cases, a study found.

An estimated 6 million people are infected with the parasite in Thailand. High rates have also been observed in neighboring Laos, where a traditional dish is made from raw fish, according to the study in the o­nline journal PLoS Medicine.

The worm, endemic in the Mekong River countries of Thailand, Laos, Vietnam and Cambodia, is ingested through the fish and attaches to the liver. Over several decades, the infection can create ulcers and inflammation leading to tumors and cholangiocarcinoma, or cancer of the bile ducts. Most patients typically develop cancer in their 40s or 50s.

"It is quite slow growing. But when it turns out to be cancer, it is very rapid," said Banchob Sripa of Khon Kaen University's Pathology Department in Thailand. "If you start out getting diagnosed today, maybe in the next six months you will die."

The disease is rare, making up less than 1 percent of all cancers worldwide in 2002. But it is much more common in Khon Kaen province, where liver cancer strikes nearly o­ne in 1,000 men—nearly all cases bile duct cancer. Women are three times less likely to develop the disease, Banchob said.

Koi-pla, the Thai name for a dish of minced raw fish mixed with hot chilies and local spices, is a staple in Khon Kaen. The fish are typically caught in rivers or ponds that are often contaminated by untreated sewage.

In southern Laos, where people share the same culture and ethnic background as those in northeastern Thailand, villagers eat a similar raw fish dish and liver parasite infection is also a problem.

Asia is home to about three-quarters of the world's liver cancers, caused largely by hepatitis B infections.

No comments: