Renal cell carcinoma, or RCC, is the most common type of primary kidney cancer. There are several subtypes of RCC, based on the cell type affected, and the most prevalent is clear cell renal cell carcinoma, or CCRCC. According to the Kidney Cancer Association, in 2009, approximately 49,000 people in the United States were diagnosed RCC and 11,000 died from it. Symptoms of RCC may include blood in the urine, flank pain, abdominal mass, and weight loss, or there may be no symptoms at all. The most well-established risk factors for developing RCC include smoking, obesity, and high blood pressure. A small percentage of RCC cases result from hereditary conditions.
Smoking
According to a 2006 study in "Seminars in Oncology," smoking increases the risk of developing renal cell carcinoma by 10 to 30 percent. The increased risk is related to the amount a person smokes. If the person quits smoking, the risk of developing RCC diminishes; however, it takes many years to reach the risk level of an individual who has never smoked. Cigarette smoking harms the kidneys in two main ways: First, with smoking, carcinogens enter the blood steam, get filtered by the kidneys, and are ultimately excreted in the urine. Along the way, these carcinogens damage the kidney tissues. Second, nicotine and other cigarette substances negatively impact the nervous and cardiovascular systems, and these effects can result in kidney damage. Aside from CCRCC, smoking can lead to other forms of kidney cancer and renal failure.
Obesity
The aforementioned 2006 study reports that obesity contributes to the development of 30 percent of renal cell carcinoma. According to 2010 information from the World Health Organization (WHO), an estimated 300 million people worldwide are obese, and complications of obesity include type 2 diabetes, cardiovascular diseases including high blood pressure and stroke, osteoarthritis, sleep apnea, liver disease, and kidney damage such as in RCC. Obesity places considerable strain on all the body's organs, and the strain on the kidneys may lead to CCRCC or other forms of kidney disease. Also, obesity-related hormone changes may play a role.
Hereditary Conditions
Hereditary genetic disorders are associated with a small percentage of CCRCC sufferers. The most common disorder is von Hippel-Lindau, or VHL, disease. VHL disease is caused by a genetic mutation in the VHL gene, and it causes tumors in many different parts of the body, such as the eyes, brain, spinal cord, pancreas, and adrenals. People with VHL disease have a higher likelihood of developing CCRCC. Other DNA-related disorders related to kidney cancer include familial renal carcinoma, papillary RCC, tuberous sclerosis, polycystic kidney disease, and Birt-Hogg-Dube syndrome.
References
- MD Consult; Renal Cell Carcinoma; Basir Tareen, M.D., et. al.; Apr 2010
- American Cancer Society: Kidney Cancer (Adult) - Renal Cell Carcinoma
- Kidney Cancer Association: About Kidney Cancer
- "Seminars in Oncology"; Epidemiologic aspects of renal cell carcinoma; JK McLaughlin, et. al.; 2006
- World Health Organization: Fact Sheet on Obesity
