The Threat of Multiple Liver Carcinogens in the Population of Laos: A Review

Abstract

Laos is a landlocked country in South East Asia, ranking fifth for primary liver cancer incidence worldwide. Risk factors that might explain this worrying situation are poorly known. We conducted a review of the literature concerning the etiologies of terminal liver diseases in Laos. A double infectious burden with hepatitis B and C viruses and the liver fluke Opisthorchis viverrini seems to be the main cause of the high liver cancer incidence. Moreover, it was also suggested that mutagenic substances frequently found in tobacco, alcoholic beverages, fermented fish, and mold-contaminated cereals or nuts, which are all substances heavily consumed by Lao people, lead to the accumulation of DNA mutations in the liver cell genome causing tumor processes. However, the respective proportions of liver cancer cases attributable to each category of infections and substances consumed, as well as the histological nature of the neoplasia are still not precisely documented in Laos. The international medical and scientific communities as well as public health stakeholders should urgently consider the alarming situation of liver health in Laos to stimulate both research and subsequent implementation of prevention policies.

Concealed for a Long Time on the Marches of Empires: Hepatitis B Virus Genotype I

“…In Laos, genotype I was found in blood donors from the national capital Vientiane, located in the northern part of the country [ 22 ]. We isolated five genotype I strains in chronically infected patients from regions (Vientiane, Xiengkouang, Huaphan, and Phongsaly) located in Northern Laos but none from Central and South Laos [ 39 ]. Outside Southeast Asia, two patients both originating from Vietnam have been characterized in France and Canada [ 40 , 41 ].…”

Estimating the burden of hepatitis B virus infection in Laos between 2020 and 2021: A cross-sectional seroprevalence survey

“… 7 As a consequence, severe liver diseases including cirrhosis and cancer are estimated to be common in the country. 3 , 8 This is especially true for liver cancer, for which the age-standardized incidence rate is one of the highest in the world, both for women and men (14.2 and 35.7 cases for 100,000 respectively in 2021). 9 This major Public Health issue prompted the Lao government to progressively implement a nationwide anti-hepatitis B immunisation campaign of newborns, starting in 2001.…”