About Kidney Cancer

Most people have two kidneys, one on each side of the backbone, above the waist. The tiny tubules in the kidneys filter and clean the blood, taking out waste products and making urine. The urine passes from each kidney into the bladder through a long tube called a ureter. The bladder stores the urine until it is passed from the body.

Kidney cancer includes renal cell carcinoma (cancer that forms in the lining of very small tubes in the kidney that filter the blood and remove waste products) and urothelial carcinoma (cancer that forms in the center of the kidney where urine collects).  Renal cell carcinoma and urothelial carcinoma act differently and are treated differently.

Risk factors for kidney cancer include:

• Smoking
• Misusing certain pain medicines, including over-the-counter pain medicines, for a long time.
• A family history of kidney cancer, indicating a possible hereditary genetic condition such as von Hippel-Lindau.

Today, about 80% of kidney cancers are detected accidentally when CT scans are obtained for other reasons. These cancers typically are less aggressive than the ones that cause symptoms, such as blood in the urine or pain in the side.

• What tests and procedures may be used to detect kidney cancer?

  Physical exam and history: An exam of your body will check general signs of health, including signs of disease, such as lumps or anything else that seems unusual. A history of your health habits and past illnesses and treatments is also relevant.

  Blood chemistry studies: A blood sample may be checked to measure the amounts of certain substances released into your blood by organs and tissues in your body. A higher or lower than normal amount of a substance can be a sign of disease in the organ or tissue that makes it. Overall kidney function can be determined by measuring a substance called creatinine.

  Urinalysis: This is a test to check the color of urine and its contents, such as sugar, protein, red blood cells, and white blood cells.

  Urine cytology: Examination of urine under a microscope can detect abnormal cells. Urothelial cancer in the kidney may shed cancer cells into the urine. Renal cell carcinoma would not be detectable with a cytology.

  Liver function test: A sample of blood can measure the amounts of enzymes released by the liver. An abnormal amount of an enzyme can be a sign that cancer has spread to the liver. Certain conditions that are not cancer may also increase liver enzyme levels.

  Ultrasound exam: This is a procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and produce echoes. The echoes form a picture of body tissues called a sonogram.

  CT scan (CAT scan): A CT scan makes a series of detailed pictures of areas inside the body through a computer linked to an Xray machine. A dye may be injected into your vein or swallowed to help your organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.

  MRI (magnetic resonance imaging): An MRI is a procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside your body.

  Ureteroscopy: This is a surgical procedure to look inside the ureter and renal pelvis to check for abnormal areas. A ureteroscope is a thin, tube-like instrument with a light and a lens for viewing. The ureteroscope is inserted through the urethra into the bladder, ureter, and renal pelvis. A tool may be inserted through the ureteroscope to take tissue samples to be checked under a microscope for signs of disease. This test typically is performed if your urologist suspects that you have urothelial carcinoma, since that type of cancer can be seen from within the urinary tract.

  Biopsy: During a biopsy, cells or tissues are removed so they can be viewed under a microscope by a pathologist to check for signs of cancer. To conduct a biopsy for renal cell cancer, a thin needle is inserted into the tumor, and a sample of tissue is withdrawn.

• What factors affect the chance of recovery and kidney cancer treatment options?

  Your prognosis and treatment options depend on the stage of the disease, the aggressiveness of the disease as determined by the grade, your age and general health, and the status of your other kidney.

• How is kidney cancer treated?

  There are many ways of treating kidney cancer. Your urologist at Minnesota Urology will help navigate you through those options so you can choose the one that is best for you. Some of the treatment options include:

  • Radical Nephrectomy: Removal of the entire kidney. This is generally reserved for larger cancers and cancers that cannot be removed from the remainder of the kidney while still leaving behind a functioning kidney. This is commonly performed with a minimally invasive technique called robotic surgery, but occasionally tumors are large enough or complex enough that robotic surgery is not feasible.

   

  • Partial Nephrectomy: Removal of just the tumor. This is the most common surgical method used for treating kidney cancer. Typically, this is performed via a minimally invasive technique called robotic surgery. The tumor is removed, and the remainder of the kidney is repaired. For small to medium-sized tumors, the chance that the cancer will come back is the same with removal of the kidney or just the tumor, assuming that the surgeon can remove all of the tumor. With removal of part of the kidney, the remainder of the kidney continues to function, and subsequent kidney failure is less likely. For these reasons, partial nephrectomy, while technically more challenging, is favored for smaller and medium-sized tumors.

   

  • Radical Nephroureterectomy: Removal of the entire kidney and ureter. For patients who have urothelial carcinoma of the kidney or ureter, removal of the entire kidney and ureter tube is often the best option. This is usually performed with minimally invasive robotic surgery.

   

  • Ablation: Destruction of the tumor. Some small tumors can be destroyed by inserting a probe into the mass and introducing either extremely cold temperatures (cryoablation) or radio frequency waves. These procedures are guided by CT imaging or ultrasound and require a simple puncture through the skin. Most patients are discharged the same day. In properly selected patients, the cure rate can be close to that of removal of the tumor.

   

  • Surveillance: Watching the tumor. For most small tumors that are detected by accident and are not causing any symptoms, the growth rate is quite slow (1 mm per year), and the chance for metastasis (“spread”) is extremely low. For some patients, these tumors will never cause any problems. For this reason, watching the tumor with periodic imaging is a reasonable option. If the tumor grows faster than expected, one of the active interventions may be chosen.