The kidneys are two bean-shaped organs — approximately the size of a fist — that filter urine and waste out of the blood. Kidney cancer, also known as renal cancer, is a form of cancer that forms in one or both of the kidneys. It typically originates in the lining of tiny tubes (tubules) in the kidney, which is known as renal cell carcinoma.
What causes kidney cancer?
While the cause of kidney cancer is unknown, there are risk factors that may increase the risk of developing kidney cancer. These include:
- Certain genetic conditions (e.g., von Hippel-Lindau syndrome, Birt-Hogg-Dubé syndrome)
- Hypertension (high blood pressure)
- Long-term dialysis to treat chronic kidney failure
- Obesity
- Older age
- Smoking
What are the symptoms of kidney cancer?
Symptoms of kidney cancer rarely appear in the early stages. Symptoms seen in the later stages include:
- Fatigue
- Hematuria — or blood in the urine — where urine may appear pink, red or cola-colored
- Pain below the ribs that doesn’t dissipate
- Sporadic fever
- Weight loss
What are the types of kidney cancer?
In adults, renal cell carcinoma is the most common form of kidney cancer. Children, however, are more likely to develop a rare form of kidney cancer known as Wilms’ tumor or nephroblastoma.
How is kidney cancer diagnosed?
Tests to confirm a diagnosis of kidney cancer may include:
- Blood and urine tests to determine the cause of symptoms.
- Imaging tests, including an ultrasound, magnetic resonance imaging (MRI) or computed tomography (CT) scan.
- Tissue sample or biopsy from a suspicious area on the kidney.
Once a diagnosis is confirmed, a physician will determine which stage the cancer is in.
Stages of kidney cancer are:
- Stage I: The tumor can be up to 2 ¾ inches in diameter, but is confined to the kidney.
- Stage II: A stage II tumor is larger than a stage I tumor, but is still confined to the kidney.
- Stage III: The tumor has spread beyond the kidney to the surrounding tissue and may also have spread to a nearby lymph node.
- Stage IV: The cancer has spread beyond the kidney to lymph nodes or to other parts of the body (e.g., liver, lungs or bones).
How is kidney cancer treated?
Treatment for kidney cancer depends on a number of factors, including:
- Overall health
- Stage of kidney cancer
- Treatment preferences
- Type of kidney cancer
Surgery is the most common form of treatment for kidney cancer. Surgical treatment options include:
Also known as nephron-sparing surgery. During a partial nephrectomy, the tumor and a margin of healthy tissue is removed. This may be performed traditionally (open procedure with a large incision), laparoscopically (through a small incision) or utilizing robotic technology. It is a common treatment for smaller kidney cancers and is generally preferred over a radical nephrectomy.
In this procedure, the affected kidney is completely removed along with a border of healthy tissue, nearby lymph nodes and possibly the adrenal gland (a gland that produces a variety of hormones). This may be performed traditionally, laparoscopically or utilizing robotic technology.
Treatments for when surgery isn’t an option. In some cases, surgery is not a treatment option for patients with kidney cancer. When this occurs, other treatments may include:
This technique uses an X-ray-guided needle to insert gas into the tumor that freezes the cancer cells.
Like cryoablation, an X-ray-guided needle is injected into the tumor. However, rather than freezing the cancer cells, an electrical current is passed through the mass to heat and burn the cells.