Vol. 9, No 1, 2002 pp. 108 - 113
UC 616.61-004 616.62-006
MALIGNANT BLADDER TUMORS AND BALKAN ENDEMIC
NEPHROPATHY: POSSIBLE COMMON ETIOLOGIC FACTORS
Branislav Petrović1, Biljana Kocić2,
Rade Čukuranović2, Vladisav Stefanović2
1Institute of Epidemiology, Faculty
of Medicine, Niš, Serbia
2Institute of Nephrology and Hemodialysis,
Faculty of Medicine, Niš, Serbia
Summary. The aim of this work is to establish the most important
epidemiologic features of malignant bladder tumors (based on the investigations
so far), to get an insight into the risk factors and explain possible association
with Balkan endemic nephropathy. Data from the most important studies were
used, published in the country and abroad in scientific literature. Morbidity
and mortality rates were expressed per 100.000 inhabitants. The most common
primary malignant bladder tumors are: carcinoma transitocellulare (80-90%),
planocellular carcinoma (3-7%), adenocarecinomas (1-2%) and malignant sarcomas
(1%). Bladder cancer belongs to the group of 12 most frequently registered
new malignant tumors per year, in both sexes, and in industrial countries
it is even more common. People living in highly developed countries in
Europe and North America are most frequently affected, as well as those
in the regions with endemic schistosomiasis (Africa) and Taiwan. In highly
developed countries bladder cancer mortality demonstrates the lowest degree
of variability compared to other regions. Mortality rates are higher in
male population. Bladder cancer affects mainly male population. Male/female
ratio differs from country to country and it is usually 4:1, but there
are regions with much higher or lower ratio. The highest incidence and
mortality rates are registered in those over 75 years of age (more than
140/100.000 men) or those over 30 in female population. The connection
of bladder cancer to upper part urothelial tumors has been established
in many investigations, but this connection for bladder cancer was seen
only in some recent studies. According to different investigations, the
incidence of bladder malignant tumors was 1.5 to 8.4 (mainly 3 to 4) times
higher in the endemic regions for BEN versus the non-endemic. Possible
common etiologic factors for BEN and malignant bladder tumors, established
in various independent studies may be: genetic basis, lack of oligoelements
and antioxidants in food and drinking water, and exposure to different
aromatic hydrocarbons. Both BEN and urothelial tumors (bladder cancer as
well) are probably the diseases with multifactorial etiology, for the occurrence
of which, in addition to genetic hypotheses, environmental factors are
responsible too. It may well be spoken of the same external factors the
effect of which depends on their concentration in an organism, duration
of exposure and type of cells they act upon. However, to establish the
etiology of both diseases it is necessary to perform many multidisciplinary
studies including scientists from various fields: geneticists, toxicologists,
clinical physicians, epidemiologists, geologists and others.
Key words: Bladder cancer, Balkan endemic nephropathy, etiology
