The kidneys are a pair of bean-shaped organs located in the abdominal area. They function to remove waste products from the body by converting waste into urine, which then flows into the bladder for elimination. Kidney cancer occurs when kidney cells grow abnormally. The cause of this abnormal growth is unknown, but kidney cancer affects an estimated 50,000 Americans each year.

The most common type of kidney cancer is renal cell carcinoma, although transitional cell carcinoma and Wilms’ tumor (mostly affecting children) kidney cancers also exist.

Kidney Cancer Symptoms

In its earliest stage, kidney cancer does not present any symptoms. However, later stage patients may experience:

• Back and/or abdominal pain
• Dark, rust or brown colored urine
• Blood in urine
• Weight loss

Those at highest risk for kidney cancer are older males who are smokers. Obesity and high blood pressure also are risk factors.

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