what's kidney cancer

Kidney cancer, or cancer of the kidney, is any type of cancer that has arisen from the kidney. Kidney cancer does not usually include a cancer that arose outside the kidney and metastasized to include metastatic cancer of the kidney. 

The most common types of kidney cancer include renal cell carcinoma and urothelial cell carcinoma of the renal pelvis. Renal cell carcinoma accounts for approximately 90% of all kidney cancers. Urothelial cell carcinoma is a type of cancer that occurs in the urinary system, specifically the kidney, urinary bladder, ureter, urethra and urachus.

The following are also types of kidney cancers:

1. Juxtaglomerular cell tumor (reninoma)
2. Angiomyolipoma
3. Renal oncocytoma
4. Bellini duct carcinoma
5. Clear-cell sarcoma 
6. Squamous cell carcinoma
7. of the kidney
8. Mesoblastic nephroma
9. Wilms' tumor (usually diagnosed in children under 5)
10. Mixed epithelial stromal tumor

On very rare occasions these cancers and potentially cancerous tumors that usually originate in other parts of the body, can start off in the kidneys: clear cell adenocarcinoma, transitional cell carcinoma, inverted papilloma, renallymphoma, teratoma, carcinosarcoma, carcinoid tumor of the renal pelvis. 

Kidney cancers originate mainly in two parts of the kidney - the renal tubule and the renal pelvis. Most that originate in the renal tubule are renal cell carcinoma and clear cell adenocarcinoma. Most cancers that originate in the renal pelvis are transitional cell carcinoma. 

3% of all adult cancers in the Western Europe are kidney cancers. There were 5,745 diagnosed cases of kidney cancer in England and Wales in 2004. In the USA there are over 50,000 newly diagnosed cases of kidney cancer each year, causing over 13,000 deaths annually. Worldwide, approximately 208,000 cases of kidney cancer are diagnosed annually, accounting for nearly 2% of all cancers. Regions in Asia and Africa have the lowest rates of kidney cancer worldwide, while North America has the highest rate. 

In the UK kidney cancer is the eighth most common form of cancer in adult men and the fourteenth most common in adult women. 

Adults aged between 50 and 80 years are more likely to develop kidney cancer compared to other people. This type of cancer affects men more than women. 

The incidence of kidney cancer in the developed world has been steadily increasing over the last three decades. Some experts believe there is a close link between this increase and a parallel rise in rates of adult obesity.
 see an article  here about kidney cancer symtoms
see  an article about what are the causes of kidney cancer and risk factors