Purpose: Hepatocellular carcinoma (HCC) is a leading health problem worldwide. Any agent causing chronic liver damage and cirrhosis is a risk factor for HCC. Genetic and environmental factors may be responsible for regional variations in the occurrence of HCC worldwide. The aim of this review was to describe the risk factors that may be contributing to low prevalence of HCC in the Mexican population. Methods: An electronic systematic search was conducted in four databases to retrieve studies on

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... hepatocellular carcinoma in Mexico. Results: Eighteen publications gave a total of 1042 HCC cases with a percentage that ranged from 0.25% to 1.87%. Cirrhosis was registered in 7 studies while the main etiologies were: HCV (66%), HBV (11%) and alcoholism (6.6%). Conclusions: In the last 50 years, the studies performed in Mexico have shown a very low incidence and/or mortality rate of HCC. These findings contrast from those reported in high endemic regions, such as Asia, where viral hepatitis and HCC are prevalent. One significant difference is the predominance of HBV genotype H in Mexico and HBV/B and C in Asia. In Mexico, high endemic areas of HBV infection have been detected, mainly among the native population; however, infection seems to resolve very quickly, due to a prominent immunological response among the population. Other factors are that patients with liver cirrhosis die prematurely before that HCC can be detected. Furthermore, an environmental factor that may exert a protective effect against HCC, in spite of the high consumption of potentially aflatoxin-contaminated food products, is the neutralization of these substances by alkaline treatment. This study shows that genetic and environmental factors associated to HCC among the Mexican population are different from others reported worldwide.