The exact causes of renal cell cancer are unknown, while the single greatest cause of bladder cancer is smoking. Risk factors for these conditions are given below.
- Smoking: Smoking increases the likelihood of developing kidney cancer—and the more you smoke, the greater the chance.
- Asbestos: Research has shown a link between asbestos exposure and kidney cancer.
- Cadmium: Exposure to cadmium may have a link to kidney cancer, and may also strengthen the link between kidney cancer and smoking.
- Family history: A family history of kidney cancer increases a person’s risk of developing it. In addition, people with hereditary syndromes, such as hereditary papillary renal cell carcinoma, hereditary leiomyoma-renal cell carcinoma and hereditary renal oncocytoma, are more likely to develop kidney cancer.
- Gender: Men are twice as likely as women to develop renal cell cancer.
- Von Hippel-Lindau syndrome: This is a genetic disorder that increases one’s chances of developing renal cell cancer.
- Birt-Hogg-Dube syndrome: This is a genetic disorder that increases a person’s susceptibility to renal cancer.
- Obesity: Obesity has been linked to an increased chance of kidney cancer.
- Advanced kidney disease: Patients who have been on dialysis for a long time because of advanced kidney disease are at an increased risk of developing renal cell cancer.
- High blood pressure: Individuals with high blood pressure are more likely to develop kidney cancer.
- Diuretics: Water pills or drugs that eliminate excess body fluid have been linked to an increased risk of kidney cancer, though the evidence on this association isn’t clear.
- Race: African Americans have a slightly higher chance of developing kidney cancer.
It’s worth noting that many people who develop kidney cancer have none of these risk factors, and many people with one of more of these risk factors never develop kidney cancer.
- Smoking: Smoking is the single biggest risk factor for bladder cancer. Carcinogens in cancer become concentrated in the urine, eventually damaging the lining of the bladder and increasing the chance of a cancer-causing genetic mutation. Smokers are twice as likely as nonsmokers to develop bladder cancer—and that risk goes up the more and longer they smoke.
- Occupational risk factors: Repeated exposure to certain chemicals used to manufacture dyes, rubber, leather and paint products may increase the risk of bladder cancer, especially for smokers. In addition, drinking water with high levels of arsenic has been linked to bladder cancer as well.
- Age: Individuals over the age of 70 develop bladder cancer at two or three times the rate of those aged 55 to 69, and as much as 20 times more than those aged 30 to 54.
- Race: Caucasians are more likely to develop bladder cancer than African Americans and Latinos. Asians have a relatively lower risk of developing this cancer.
- Sex: Men are four times as likely as women to develop bladder cancer, perhaps because of hormonal imbalances.
- Chemotherapy and radiation therapy: The anti-cancer drugs cyclophosphamide and ifosfamide have been linked to an increased risk of bladder cancer. In addition, women being treated with radiation therapy for cervical cancer have in some studies been shown to have an elevated bladder cancer risk as well.
- Chronic bladder inflammation: Chronic and repeated urinary infections and cystitis (a urinary tract infection) have been linked to an increased risk of squamous cell carcinoma of the bladder. In addition, a chronic parasitic infection most common in North Africa can lead to squamous cell carcinoma, though this is uncommon in the United States.
- Genetics: Mutations of several genes that regulate cell division and prevent uncontrolled cell growth have been linked to an elevated risk of bladder cancer.
- Diet: A diet high in fat and low in fruit and vegetable consumption significantly increases a person’s risk of bladder cancer.
- Bladder birth defect: Rare birth defects of the bladder can lead to an unusual form of bladder cancer called adenocarcinoma.
- Personal history: A person who has had bladder cancer in the past is at a higher risk of it coming back—sometimes the tumors will form in the ureters or urethra as well as the bladder.