Microcystins: Potential risk factors in carcinogenesis of primary liver cancer in Serbia

Abstract

The Primary Liver Carcinoma (PLC) is one of the most common malignant diseases in the world. In Central Serbia during the period from 2000 to 2006 the average incidence was 16.9/100 000 that complies to the European epidemiology. The main risk factors for PLC are considered to be cirrhosis of liver and viral chronic Hepatitis B and C. The goal of this research was to analyze epidemiological data of these diseases and to state the correlation between PLC, liver cirrhosis and Hepatitis B and C in Serbia. During the research period of 6 years the correlations between PLC and the corresponding risk factors were negative. For this reason it was necessary to examine other risk factors. The high incidence of PLC in Nišavski, Toplički and Šumadijski region correlate with emerging blooms of Cyanobacteria in water reservoirs supplying these areas with drinking water. Since we examined only 7 years span and have no completed cyanotoxin analysis, it is necessary to complete more research in this field. The identification of cyanotoxins as risk factors that contribute to the development of liver cancer will help in the prevention of this disease.

Epidemiology of Primary Liver Cancer in Serbia and Possible Connection With Cyanobacterial Blooms

“…Figure 8 shows a downward curve of PLC incidence from the Nišavski district with the highest incidence, to the Rasinski district with the lowest, from 2000 to 2006. At the same period, the courses for liver cirrhosis mortality and incidence of HBV and HCV for given districts are very similar to each other, but do not correspond to the distribution of PLC incidence [57]. This may indicate that there are some other factors greatly affecting the occurrence of liver cancer in addition to these well-known and generally accepted risk factors.…”

“…Therefore, during the observed period, there was no correlation between PLC and these diseases that are considered to represent its most important risk factors. This could be clearly recognized in six-year epidemiological study of PLC incidence and mentioned risk factors (Figure 8) [57]. Figure 8 shows a downward curve of PLC incidence from the Nišavski district with the highest incidence, to the Rasinski district with the lowest, from 2000 to 2006.…”

“…In recent years, research on the relationship between blooming of cyanobacteria and the PLC has been done in Serbia [8,38,[55][56][57]. For more reliable conclusions, in order to find the connection between PLC and cyanobacterial blooms, a longer period of time was analyzed in this article.…”

Review of 130 years of research on cyanobacteria in aquatic ecosystems in Serbia presented in a Serbian Cyanobacterial Database

“…MCs) from drinking water could present a risk factor for primary liver cancer and possibly even other types of cancer (Svirčev et al, 2010;Drobac, 2015). Epidemiological studies conducted in Serbia have revealed a significant correlation between an increased incidence of several cancers (brain; heart, mediastinum and pleural; ovarian; testicular; gastric; colorectal; retroperitoneal and peritoneal; leukemia; malignant skin melanoma; and primary liver cancer) and cyanobacterial blooms in reservoirs used for drinking water supply (Svirčev et al, 2009(Svirčev et al, , 2013b(Svirčev et al, , 2014bDrobac, et al 2011;Drobac, 2015).…”

Human Exposure to Cyanotoxins and their Effects on Health

“…The prevailing opinion in the literature is that the development of PLC results from cirrhosis and chronic viral hepatitis (HBV and HCV). However, this could not be concluded from the obtained data on the incidence of PLC, HBV, HCV, and liver cirrhosis mortality in central Serbia from 2000 to 2006; no correlation between PLC and these diseases was found (21). On the other hand, epidemiological studies in Serbia have shown that the consumption of drinking water contaminated by MCs could be connected to human PLC (9,20,22).…”