Taussig Cancer Institute's GU Medical Oncology Program has ongoing multidisciplinary clinics with colleagues from the Glickman Urologic and Kidney Institute and the GU section of the Department of Radiation Oncology. Urologic oncologists, pediatric urologists, medical and radiation oncologists, radiologists, and genitourinary pathologists at the Clinic collaborate to provide services for more than 1,000 adrenal, renal (kidney), bladder, prostate and testicular cancer and Wilms’ tumor patients annually. More than 350 surgical procedures for urologic cancer are performed each year.
What is renal cell carcinoma?
Kidney Cancer – also called renal cell carcinoma, kidney adenocarcinoma or hypernephroma, as well as renal cancer – accounts for about 3 percent of new cancers in the United States, an estimated 33,000 new cases of kidney cancer in 2005.
Kidney cancer includes several forms.
Clear cell is the most common type of renal cancer, accounting for 75-80 percent of kidney tumors. It can be in pure form or mixed with other types of cells (such as granular cells or sarcomatoid cells). Papillary tumors account for 10-15 percent of cases of renal cell carcinoma.
Although there are biologic differences between different subtypes of kidney cancer, no differences in treatment approaches yet exist. Oncocytomas and chromophobe subtypes are much less aggressive forms of kidney cancer.
Another type of kidney cancer, Wilms’ tumor, is found almost exclusively in children.
What are the symptoms of kidney cancer (renal cell carcinoma)?
The most common symptom of kidney cancer is blood in the urine (hematuria), which is present in up to 65 percent of cases. Abdominal pain is found in 40 percent of patients with renal cancer and an abdominal mass in 35 percent.
Other common symptoms of renal cancer include anemia, bone pain, unexplained weight loss, low-grade fever, general weakness or loss of energy and loss of appetite.
Unusual symptoms of kidney cancer may include hypercalcemia (high blood calcium), high blood pressure, abnormal liver tests or too many red cells in the blood (polycythemia). These symptoms develop because renal tumors can produce substances that indirectly affect other organs, producing conditions called paraneoplastic syndromes.
None of the currently available screening techniques (urinalysis or ultrasound) are helpful in detecting kidney cancer and not routinely used.
How is renal cell carcinoma diagnosed?
History – A doctor may suspect kidney cancer if a patient complains of the common symptoms noted above.
Physical Examination – An abdominal mass may be felt below the rib cage in the back or side area.
Blood and Other Tests for Kidney Cancer
Urinalysis – can detect blood in the urine; one cause of this is kidney cancer although it is not the most common cause (kidney stones, infection and trauma would be other causes).
Liver function tests – can be abnormal if the cancer has spread to the liver.
Complete blood count – the red blood cell count (the hemoglobin or hematocrit) can be high or low.
Blood calcium – kidney cancer can lead to a high calcium level by releasing hormone-like proteins.
Imaging
Intravenous pyelogram (IVP), also called excretory urography. The IVP is a detailed X-ray of the kidney and suspected tumor. It is taken after the injection of a relatively harmless contrast medium into the bloodstream that supplies the kidney. The material is concentrated in the urine and provides a silhouette of the kidney. This reveals any changes in the kidney’s shape due to a tumor and gives information about the other normal kidney.
Ultrasound is the most sensitive test, and is able to find masses as small as 3/4 inch (2 cm) in over 90 percent of cases. Ultrasound can often distinguish between the more common benign or non-cancerous cyst and a solid tumor. When this test is combined with the intravenous pyelogram (IVP), the accuracy of a tumor diagnosis is over 90 percent. The sonogram can also be very helpful in determining whether the tumor has induced a clot in or invaded the renal vein or the inferior vena cava.
CT (computed tomography) with intravenous dye (the same dye used for an IVP) will accurately diagnose renal tumors in 95 percent of cases and be falsely positive in fewer than 2 percent. This test may also show if the tumor extends outside the kidney and can determine the extent that lymph nodes, the liver and blood vessel are involved.
MRI (magnetic resonance imaging) is used for determining more clearly the extent of blood vessel involvement and involvement of adjacent structures. It is useful in obtaining preoperative information in some patients with particularly large tumors. It is not routinely used for all patients.
Biopsy
Ultimately, the diagnosis of kidney cancer is made either by removing the kidney (nephrectomy) or by a biopsy of the kidney itself or of a tumor in another organ. Looking for tumor cells in the urine is not useful.
What are the kidney cancer treatment options?
Surgical removal of the kidney and the surrounding fat, adrenal gland and possibly lymph nodes (radical nephrectomy) can lead to a cure for Stages I and II (disease confined to the kidney) and can potentially cure Stage III patients (disease involving lymph nodes and/or larger blood vessels) in select cases. Stage IV (metastatic disease) requires therapy and kidney cancer treatment that goes throughout the whole body (systemic therapy).
Surgery for Kidney Cancer Treatment
Partial nephrectomy (removal of part of one kidney) is usually performed for patients with tumors smaller than about 4 cm or tumors smaller than about 7 cm in patients with either one kidney or health conditions that could affect future kidney function. Radical nephrectomy is generally accepted as the standard kidney cancer treatment approach. Recent studies have also shown a benefit in some patients to removing the cancerous kidney even when the disease has already metastasized. Surgery in this setting is most often performed in younger, healthier patients with the majority of their cancer in the kidney. It is not appropriate for all patients with metastatic disease.
Therapy after Kidney Cancer Treatment
After surgery that removed all visible cancer, there is still a chance the cancer may return, depending on a number of factors. There is no evidence that pre-operative (neoadjuvant) or post-operative (adjuvant) therapy (either radiation, immunotherapy or chemotherapy) reduces this risk in kidney cancer. Because therapy might expose the patient to toxicity without proven benefit, such kidney cancer treatment should be given only as part of a clinical trial.
Biological Therapy (Immunotherapy)
The standard therapy for renal cell carcinoma involves the use of biological proteins. Several of these proteins regulate the immune system and are normally produced by the body. These proteins (also called cytokines) can be manufactured and administered at higher doses to stimulate a patient’s immune response against the cancer. Interferon-alpha has a 15-20 percent response rate (meaning tumors shrink in these patients).
Interleukin-2 (IL-2), the only FDA-approved drug for the treatment of renal cell carcinoma, also has a 15-20 percent response rate, including a small number of complete responses (complete disappearance of all tumors) that can be durable. These cytokines are given as injections under the skin three to five times per week and cause flu-like symptoms.
The use of intravenous high-dose IL-2 (in the dosage in which it was approved by the FDA) is sometimes given to younger, healthy patients. It requires admission to an intensive care unit because of potentially fatal toxicity. This treatment may, however, lead to a slightly higher overall and complete response rate and may be appropriate for select, younger patients. Your doctor will discuss using one or both of these cytokines and the dose with you.
Angiogenesis Inhibitors
This new class of anti-cancer drugs attempts to reduce tumor growth by inhibiting the formation of new blood vessels around tumors. There are many different drugs designed to accomplish this. These new drugs include bevacizumab (Avastin), SU11248 (Sutent) and BAY 43-9006 (sorafenib; Nexavar) which are now being evaluated in clinical trials. Preliminary results show tumor responses in 10-40 percent of patients.
