Kidney Cancer Renal Cell Carcinoma

The most common form of kidney and pelvis cancer is renal cell carcinoma (RCC). In fact, this type of cancer accounts for 90 percent to 95 percent of all kidney cancers. Though RCC has few early signs and is very resistant to most forms of radiation and chemotherapy, recently developed targeted treatments have had more success against it.

Causes and Risk Factors for Renal Cell Carcinoma

The primary function of the kidneys is to filter wastes from the blood. To accomplish this, the kidneys contain many small tubes, called tubules. Renal cell carcinoma develops on the lining of these tubules.

Though the cause of renal cell carcinoma is not known, identified risk factors include:

  • age of 50 to 70 years
  • dialysis treatment
  • family history of the disease
  • male gender (RCC is twice as common in men than in women.)
  • obesity
  • smoking and tobacco use (doubles the risk of RCC)
  • von Hippel-Lindau (VHL) disease, a rare hereditary disease affecting small blood vessels in the brain (Forty percent of VHL patients develop RCC).

Symptoms of Renal Cell Carcinoma

In patients with renal cell carcinoma, symptoms are usually absent until the cancer is in an advanced stage. In fact, 25 to 30 percent of patients never experience symptoms.

The following comprise the classic triad of symptoms of advanced RCC:

  • flank mass
  • flank pain
  • hematuria (blood in the urine).

Other symptoms include:

  • fever
  • hypertension (high blood pressure)
  • hypercalcemia (excess calcium in the blood)
  • malaise
  • night sweats
  • unexplained weight loss
  • varicocele (an enlarged vein in the scrotum).

Diagnosis of Renal Cell Carcinoma

Since symptoms are usually only accompanied with later stages of tumor development, it is rare for renal cell carcinoma to be discovered in early stages.

A positive diagnosis of renal cell carcinoma is difficult to make and is usually accomplished through the use of a combination of imaging tests, including:

  • CT scans
  • MRIs
  • PET scans
  • ultrasonography (ultrasound).

In addition to imaging tests, lab tests can also help diagnose kidney cancer. Urine cytology, a lab test that uses a microscope to examine urine contents, can sometimes detect cancer cells in the urine. The form of kidney cancer that urine cytology usually detects, however, is transitional cell carcinoma. Although RCC can still be detected with this test, the diagnosis occurs less frequently.

On rare occasions, a fine needle aspiration biopsy will be taken. This technique involves pushing a small needle through the skin to remove tissue samples for examination under a microscope.

Treatment of Renal Cell Carcinoma

Roughly half of all cases of renal cell carcinoma are successfully treated in early stages of the cancer. Once the disease has progressed to stage IV, however, prognosis is usually poor. The primary treatment for RCC involves some combination of surgery, targeted therapy and immunotherapy:

  • Immunotherapy: Immunotherapy is a new form of treatment that uses drugs called cytokines to stimulate the immune system, allowing it to more effectively attack cancerous cells. The use of cytokines has been shown to reduce tumor size in 10 percent to 20 percent of patients.
  • Surgery: Surgical treatment is the only treatment that is aimed at curing the disease in early stages, though it can also reduce pain in patients with more advanced RCC. The most common form of RCC surgery is radical nephrectomy, which removes the entire affected kidney, the attached adrenal gland and the tissues around the kidney. A partial nephrectomy removes only the part of the kidney that contains the cancer and is usually performed in patients with cancer in both kidneys or when the patient has only one kidney.
  • Targeted Therapy: Targeted therapy, another new approach, uses drugs to attack specific targets in the cancer cells. These drugs work to block molecules that stimulate the growth of tumors and prevent the development of new blood vessels that feed tumors.

Radiation therapy, chemotherapy and hormonal therapy are sometimes used to treat RCC but are less effective treatments.

Resources

American Cancer Society (October 21, 2005). How is Kidney Cancer (Renal Cell Carcinoma) Diagnosed? Retrieved July 10, 2007 from the American Cancer Society Web site: http://www.cancer.org/docroot/CRI/content/CRI_2_4_3X_How_is_kidney_cancer_diagnosed_22.asp?rnav=cri.

American Cancer Society (October 21, 2005). What are the Risk Factors for Kidney Cancer (Renal Cell Carcinoma)? Retrieved July 10, 2007 from the American Cancer Society Web site: http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_What_are_the_risk_factors_for_kidney_cancer_22.asp?rnav=cri.

American Cancer Society (October 21, 2005). What is Kidney Cancer (Renal Cell Carcinoma)? Retrieved July 10, 2007 from the American Cancer Society Web site: http://www.cancer.org/docroot/cri/content/cri_2_4_1x_what_is_kidney_cancer_22.asp.

National Cancer Institute (n.d.). Kidney Cancer. Retrieved July 10, 2007 from the National Cancer Institute Web site: http://www.cancer.gov/cancertopics/types/kidney.

Sachdeva, K., Makhoul, I (June 10, 2006). Renal Cell Carcinoma. Retrieved July 10, 2007 from the eMedicine Web site: http://www.emedicine.com/med/topic2002.htm.