Kidney cancer begins when healthy cells in 1 or both kidneys change and grow out of control, forming a mass called a renal cortical tumor. A tumor can be malignant, indolent, or benign. A malignant tumor is cancerous, meaning it can grow and spread to other parts of the body. An indolent tumor is also cancerous, but this type of tumor rarely spreads to other parts of the body. A benign tumor means the tumor can grow but will not spread.
Renal cell carcinoma
Renal cell carcinoma is the most common type of adult kidney cancer, making up about 85% of diagnoses. This type of cancer develops in the proximal renal tubules that make up the kidney’s filtration system.
Urothelial carcinoma
This is also called transitional cell carcinoma. It accounts for 5% to 10% of the kidney cancers diagnosed in adults. Urothelial carcinoma begins in the area of the kidney where urine collects before moving to the bladder, called the renal pelvis.
Sarcoma
Sarcoma of the kidney is rare. This type of cancer develops in the soft tissue of the kidney; the thin layer of connective tissue surrounding the kidney, called the capsule; or surrounding fat.
Wilms tumor
Wilms tumor is most common in children and is treated differently from kidney cancer in adults. Wilms tumors make up about 1% of kidney cancers.
Lymphoma
Lymphoma can enlarge both kidneys and is associated with enlarged lymph nodes, called lymphadenopathy, in other parts of the body, including the neck, chest, and abdominal cavity.
It is estimated that 14,830 deaths (9,860 men and 4,970 women) from this disease will occur in the united states.
About two-thirds of people are diagnosed when the cancer is located only in the kidney. For this group, the 5-year survival rate is 93%. If kidney cancer has spread to surrounding tissues or organs and/or the regional lymph nodes, the 5-year survival rate is 70%. If the cancer has spread to a distant part of the body, the 5-year survival rate is 12%.
Early renal cancer rarely causes signs or symptoms. There are currently Genetic tests to screen for renal cancer without symptoms. In the later stages, signs and symptoms of renal cancer may include:
- Mass in the abdomen
- Hematuria (blood in the urine)
- Loss of appetite
- Unexplained weight loss
- Tiredness
- High temperature and heavy sweating
- Persistent pain in the back
- Intermittent fever
Factors that can increase the risk of renal cancer include:
- Older age: the risk of renal cancer increases with age
- Being male: men are about twice as likely as women to get renal cancer
- Smoking: smoking is associated with an increased risk of renal cancer
- Obesity: extra weight may cause changes to hormones that increase the risk
- Family history: the risk is especially high in siblings
- High blood pressure
- Exposure to certain substances: such as benzene, asbestos, organic solvents, cadmium, or certain herbicides