The kidneys are a pair of organs located at the back of the abdomen outside the peritoneal cavity. They filter waste products and water from the blood, producing urine, which empties into the bladder through the ureters. They are also important endocrine organs concerned with salt and water metabolism and maintaining blood pH, and they play a key role in vitamin D metabolism.
Incidence and survival rates
Kidney cancer – also known as renal cancer – is the 12th most common cancer worldwide, with 337,860 cases recorded in 2012. However, the International Agency for Research on Cancer predicts a 22 per cent increase in the number of people developing the disease by 2020, amounting to about 412,929 cases (an increase of 75,069).
Statistics also show that incidence rates of the disease are twice as high among men than women and that 59 per cent of kidney cancer cases occur in more developed countries, with the highest rates seen in North America and Europe and the lowest in Africa and Asia.
Although kidney cancer is the 16th most common cause of death from cancer, survival rates are relatively high in developed countries. In the US, overall survival rates are 72 per cent after five years; the survival rate beyond five years is even higher at 92 per cent for the two thirds (64 per cent) of cases that are diagnosed in the early stages. However, these high survival rates are not seen in lower income countries where cancers are often detected at later, more advanced stages.
Lifestyle factors and kidney cancer risk
In this report from our Continuous Update Project (CUP) – the world’s largest source of scientific research on cancer prevention and survivorship through diet, nutrition and physical activity – we analyse global research on how certain lifestyle factors affect the risk of developing kidney cancer. This webpage forms part of the World Cancer Research Fund/American Institute for Cancer Research Third Expert Report Diet, Nutrition, Physical Activity and Cancer: a Global Perspective.
Findings on kidney cancer
There is strong evidence that:
- being overweight or obese INCREASES the risk of kidney cancer
- being tall INCREASES the risk of kidney cancer (the taller a person is, the greater his or her risk of kidney cancer)
- consuming alcoholic drinks DECREASES the risk of kidney cancer, when consuming up to 30 grams (about 2 drinks) a day. There is insufficient, specific evidence for higher levels of drinking – for example, 50 grams (about 3 drinks) or 70 grams (about 5 drinks) a day. It is also important to remember that there is strong evidence that alcohol is linked to an increased risk of five other cancers
There is some evidence that:
- consuming drinking water that contains arsenic might increase the risk of kidney cancer
Other causes of kidney cancer
In addition to the findings on diet, nutrition and physical activity outlined above, other established causes of kidney cancer include:
Smoking is a cause of kidney cancer. Current smokers have a 52 per cent increased risk of kidney cancer, and ex-smokers a 25 per cent increased risk, compared with those who have never smoked.
Painkillers containing phenacetin are known to cause cancer of the renal pelvis. Phenacetin is no longer used as an ingredient in painkillers.
- kidney disease
Polycystic kidney disease predisposes people to developing kidney cancer.
High blood pressure is associated with a higher risk of kidney cancer.
The kidneys filter blood and excrete metabolic waste products. These waste products include potential carcinogens, consumed as or derived from pharmaceuticals or foods and drinks, or through exposure from other environmental sources such as cigarette smoke. Some of these may play a role in kidney carcinogenesis.
Inherited genetic predisposition accounts for only a minority of kidney cancers. Von Hippel-Lindau (VHL) syndrome is the most common, with up to 40 per cent of those inheriting the mutated VHL tumour suppressor gene developing kidney cancer. Tuberous sclerosis is less common and predisposes to multiple cancer types, kidney cysts and kidney cancer. About three-quarters of kidney cancers without a familial component are a clear cell type, of which about 60 per cent have a mutation in the VHL gene. A further 12 per cent of non-familial kidney cancers are papillary, which are less likely to metastasise.
Full references and a summary of the mechanisms underpinning all the findings can be found in the kidney cancer report.
How the research was conducted
The global scientific research on diet, nutrition, physical activity and the risk of kidney cancer was systematically gathered and analysed, and then independently assessed by a panel of leading international scientists in order to draw conclusions about which of these factors increase or decrease the risk of developing kidney cancer.
Published findings in peer-reviewed journals
Selected findings from this report have been published in peer-reviewed journals. Details of the papers and links to the abstract in PubMed are below:
WCRF-AICR continuous update project: Systematic literature review of prospective studies on circulating 25-hydroxyvitamin D and kidney cancer risk. Darling AL, Abar L & Norat T. J Steroid Biochem Mol Biol. 2015. Abstract
This webpage is a summary.
For much more, download the full chapter.