Kidney Cancer (Renal Cancer)

Kidney cancer, also known as renal cancer, is a malignant tumor that develops either from the cells of the kidneys, renal cell carcinoma; or from the cells of the renal pelvis (the tube that connects the kidneys to the ureters), urothelial cancer (formerly known as transitional cell carcinoma). Tumors of the renal pelvis are responsible for about ten percent (10%) of all renal tumors and only five percent (5%) of all urothelial tumors of the urinary tract.

Kidney cancer can develop from different types of cells that make up the renal system. Regardless of the type affected, this condition causes a group of cells of the kidney to become abnormal and multiply uncontrollably, and form a malignant mass: cancer. Kidney cancer tends to evolve asymptomatically and it is often discovered by hazard. In fact, nearly 70% of kidney cancers are discovered during medical exams performed for other health problems. Patients experience symptoms when the tumor is advanced, which often leads to late diagnosis. For additional information, see kidney cancer symptoms.

With time, and if no treatment is performed, the tumor grows and spreads to neighboring organs. Cancer cells can detach from the original site and migrate to other tissues where they form new tumors, metastases. Although many advances have been made in recent years in the field of kidney cancer treatment, the conventional therapies, such as chemotherapy and radiotherapy, are not really effective. But other techniques such as, immunotherapy, may complete the therapy, when there are multiple metastases. Immunotherapeutic drugs work by stimulating the immune system to attack and destroy the cancer cells. For more info, please see kidney cancer treatment

The Kidneys

The kidneys, having a bean-shaped, are two organs which play many important functions in our body. They purify blood by extracting waste from it. They also contribute in balancing body fluids, producing urine, and helping the body to perform other important functions such as cardiac output – the amount of blood the heart pumps in 1 minute. The kidneys also produce hormones. Some control blood pressure, while others stimulate the production of red blood cells in bone marrow.

The kidneys receive and filter approximately 180 liters of blood per day to produce 1.5 liters of urine in healthy individuals. Urine is produced in a group of small units called nephrons, the functional units of the kidney. Grouped in small pyramids, the nephrons filter the blood and produce urine to remove waste from the body. Through a filter wall, the amount of water, salt and potassium is regulated.

Once produced, urine then passes through the ureters to stay in the bladder until being discharged during urination.

Kidney Cancer and Functioning of the Body

When the kidneys are affected by any serious disease such as cancer, all these functions are not performed correctly. At the beginning, certain people can experience warning signs or symptoms, but they tend to neglect them (please see kidney cancer symptoms). Toxins accumulate in the blood, which gradually leads to poisoning. Therefore, renal cancer affects the entire body at advanced stages. The best and only way to restore normal function is undergoing an effective therapy as soon as possible. Please see kidney cancer treatment.

Renal cancer is the third urologic cancer after prostate cancer and bladder cancer. Representing 3% of adult cancers, the disease affects twice men than women, especially men aged 50 years and older.

About 100,000 people die of kidney cancer worldwide every year, making the disease the twelfth leading cancer in the world. In 2012, there were an estimated 375,925 people living with kidney and renal pelvis cancer in the United States, according to the American Cancer Society (ACS). For 2015 statistics, please kidney cancer statistics.


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