PCBs may cause Kidney Cancer,
Bladder Cancer or Urothelial Cancers
| Introduction PCBs may cause kidney cancer, bladder and urothelial cancers, according to several studies included here. Kidney cancer causes are difficult and sometimes impossible to determine. Cancer of the lining of the urinary tract is related to kidney cancer. Once the cells in one part of the lining are affected there is often a field change which predisposes the lining cells (urothelium) in other parts, such as the Kidneys, to develop tumours. For this reason the tumours are called 'urothelial' and this emphasises the need to keep under careful surveillance the rest of the urinary system once the original tumour has been treated. |
The International Agency for Research on Cancer has concluded that there is some evidence to link long-term, high-level, PCB exposure in occupational settings to an increased incidence of cancer, particularly liver and kidney cancer. This conclusion is based on studies of humans exposed to PCBs contaminated with polychlorinated dibenzofurans, which may play a role in cancer development. (Source: Environment Canada) Most PCBs are contaminated with furans.
Renal cell carcinoma is the most common kidney cancer; it accounts for more than 90% of malignant kidney tumors. Less common types of tumors include transitional cell carcinomas, Wilms' tumors, renal sarcomas, renal cell adenomas, renal oncocytomas, and angiomyolipomas. In the United States, renal adenocarcinoma — cancer of the kidney — accounts for about 3% of all adult cancers.
The American Cancer Society estimates that there will be about 30,800 new cases of kidney cancer (18,700 in men and 12,100 in women) in the United States in the year 2001, and about 12,100 people (7,500 men and 4,600 women) will die from this disease. These statistics include both adults and children, and include renal cell carcinomas as well as transitional cell carcinomas of the renal pelvis. Renal cell carcinoma is the most common type of kidney cancer in adults while Wilms' tumor is the most common type of kidney cancer in children.
Risk Factors for Kidney Cancer
Lifestyle risk factors for Kidney Cancer include: smoking, obesity, certain medications (diuretics), and consumption of well-cooked meat. Also, workplace exposures to asbestos, cadmium (a type of metal), certain clothing dyes, some chemicals used in the rubber industry, and organic solvents, particularly trichloroethylene. Men have approximately twice the risk of women (which may be related to higher smoking and occupational exposures in men). Kidney cancer tends to affect adults aged 50-70 years.
Some people inherit a tendency to develop certain types of cancer. The DNA that a person inherits from their parents may have certain changes that account for this tendency to develop cancer. Sometimes, these DNA alterations also occur during fetal development inside the mother's womb.
Some changes in chromosomes and genes that cause kidney cells to become cancerous are inherited, and cause the conditions leading to hereditary (inherited) kidney cancer. Sometimes these changes are not inherited, and occur after birth, possibly due to cancer-causing chemicals or other unknown causes. (Source: The American Cancer Society)
There has been a steady increase in the incidence of renal cell carcinoma that is not explained by the increased use of diagnostic imaging procedures. Mortality rates have also shown a steady increase. From 1950 to 1989, the incidence of kidney cancers increased 109.4%, and the death rate increased 28%. For another period, from 1973 to 1998, the incidence increased 47%.
An important study appearing in the New England Journal of Medicine on July 13, 2000, confirmed what many suspected -- inherited genetic factors make only a minor contribution to susceptibility to most cancers. The researchers found that for all cancers combined, identical twins -- sharing 100 percent of their genes--developed the same disease about 10 percent of the time. For breast, prostate, and colon cancer, both twins had the disease 14-30 percent of the time. In other words, most cancer is made, not born.
Czech people are BEER DRINKERS... They put MUCH HOPS in their beer.
British drink beer, too. But the horrible wee that they drink, contains no hops.
| Variation in incidence of kidney cancer in Europe |
Age-standardised incidence rates (World Standard population) of cancers of the kidney vary from around 3 cases per 100,000 person-years in Portugal to around 20 cases per 100,000 person-years in Czech Republic and Estonia.
Lowest rates for males are observed in Northern Europe, whereas for females lowest rates are observed in Southern Europe and highest in the West.
Source:
J. Ferlay, F. Bray, P. Pisani and D.M. Parkin.
GLOBOCAN 2002
Cancer Incidence, Mortality and Prevalence Worldwide
IARC CancerBase No. 5, version 2.0
IARCPress, Lyon, 2004.
The epidemiology of bladder and kidney cancer
Abstract
Bladder and kidney cancer together account for about 5% of cancers worldwide, and represent the 9th and 14th most common cancers in terms of absolute numbers, respectively. Our knowledge of these two cancers, however, indicates that they have strikingly different etiology. A number of important occupational, lifestyle and genetic factors have been implicated in bladder carcinogenesis, which have greatly increased our understanding of this disease. In some instances, identification of these factors has contributed to the prevention or reduction of exposure to bladder carcinogens. Conversely, the etiology of kidney cancer is less well elucidated, which limits the possibilities for reducing its incidence by this approach. It is likely that much remains to be uncovered about the causes of these two cancers, and these advances will increase our appreciation of the biology of these cancers and perhaps lead to further possibilities for their prevention. In this article, we evaluate the epidemiology of bladder and kidney cancer and also discuss potential priorities for future research.
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