Women's Health Terms Beginning with the Letter "K"
Kidney cancer
Your kidneys are two bean-shaped organs, each about the size of your fist. They're located behind your abdomen, one on each side of your spine. Like other major organs in your body, your kidneys can sometimes develop cancer. In adults, the most common type of kidney cancer is renal cell carcinoma (renal adenocarcinoma or hypernephroma), which begins in the cells that line small tubes (tubules) within your kidneys. Children are more likely to develop a kind of kidney cancer called Wilms' tumor.
Kidney cancer seldom causes problems in its early stages. But as a tumor grows, you may notice blood in your urine or experience unintentional weight loss or back pain that doesn't go away. Cancer cells may also spread (metastasize) outside your kidneys to nearby organs such as your adrenal glands, pancreas and spine, as well as to more distant sites in your body.
An estimated 35,000 Americans are diagnosed annually with kidney cancer and more than 12,000 die of the disease. Yet if kidney cancer is detected and treated early, the chances for a full recovery are good.
Kidney failure
Your kidneys are two bean-shaped organs, each about the size of your fist. They're located at the back of your upper abdomen, one on either side of your spine. The kidneys' main function is to eliminate excess fluid and waste material from your blood. When your kidneys lose their filtering ability, dangerous levels of fluid and waste accumulate in your body — a condition known as kidney (renal) failure.
Sometimes kidney failure happens suddenly (acute kidney failure). This is most likely to occur after complicated surgery or a severe injury, or when blood vessels leading to your kidneys become blocked.
Chronic kidney failure, on the other hand, usually develops slowly, with few signs or symptoms in the early stages. Many people with chronic kidney failure don't realize they have a problem until their kidney function has decreased to less than 25 percent of normal. High blood pressure and diabetes — a disorder that causes high blood sugar levels — are the most common causes.
In end-stage renal disease, the kidneys function at less than 10 percent of normal capacity. At this point they simply can't sustain life. People with end-stage renal disease need either dialysis or a kidney transplant to stay alive. When a transplant isn't possible — often because of poor general health — dialysis becomes the only option.
Kidney stones
If you've ever passed a kidney stone, you're not likely to forget the experience — it can be excruciatingly painful. What's more, kidney stones (renal lithiasis) are increasingly common. One in 10 Americans will have at least one kidney stone some time in their life.
Not all kidney stones cause symptoms. They're often discovered when you have X-rays for an unrelated condition or when you seek medical care for problems such as blood in your urine or recurring urinary tract infections. The pain becomes agonizing only when a stone breaks loose and begins to work its way down from your kidneys to your bladder.
Kidney stones usually form when your urine becomes too concentrated. This causes minerals and other substances in urine to form crystals on the inner surfaces of your kidneys. Over time, these crystals may combine to form a small, hard mass, or stone.
Most small kidney stones pass into your bladder without causing any permanent damage. Still, it's important to determine the underlying cause so that you don't form more stones in the future. In many cases, you can prevent kidney stones simply by drinking more water and making a few dietary changes.

