What is Kidney Cancer?
It’s easier to understand kidney cancer information if you learn about the role the kidneys play in your body. The kidneys are two reddish-brown, bean-shaped organs located just above the waist, one on each side of the spine. They are part of the urinary system. Their main function is to filter blood and produce urine to rid the body of waste. As blood flows through the kidneys, they remove waste products and unneeded water. The resulting liquid, urine, collects in the middle of each kidney in an area called the renal pelvis. Urine drains from each kidney through a long tube, the ureter, into the bladder, where it is stored. Urine leaves the body through another tube, called the urethra.
The kidneys also produce substances that help control blood pressure and regulate the formation of red blood cells.
Several types of cancer can start in the kidney. The most common type of kidney cancer in adults is renal cell cancer. This type is sometimes called renal adenocarcinoma or hypernephroma. Another type of cancer, transitional cell carcinoma, affects the renal pelvis. It is similar to bladder cancer and is often treated like bladder cancer.
When kidney cancer spreads outside the kidney, cancer cells are often found in nearby lymph nodes. Kidney cancer also may spread to the lungs, bones, or liver. And it may spread from one kidney to the other.
When cancer spreads (metastasizes) from its original place to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the primary tumor. For example, if kidney cancer spreads to the lungs, the cancer cells in the lungs are actually kidney cancer cells. The disease is metastatic kidney cancer, not lung cancer. It is treated as kidney cancer, not lung cancer. Doctors sometimes call the new tumor metastatic or "distant" disease.