Conventional Treatments for Kidney Cancer

In the United States, 85 percent of kidney cancers are discovered by accident when a CT scan or ultrasound exam is ordered for other reasons. Because most kidney tumors are less than 5 cm (2 inches), people with kidney cancer more often than not undergo surgery to remove only part of their kidneys. This is known as a partial nephrectomy or "nephron-sparing" surgery.

For larger kidney cancers, a surgeon removes the entire kidney in what's known as a radical nephrectomy. Urological surgeons prefer to perform nephron-sparing surgery whenever possible. Compared to a radical nephrectomy, this kind of treatment has been shown to lead to better overall kidney function, with the same cure rates.

Nephron-sparing surgery

There are three types of nephron-sparing surgery: partial nephrectomy, cryoablation, and radiofrequency ablation.

Partial nephrectomy

Sparing some of the kidney can be a safeguard against future kidney problems.  If the other kidney were injured or diseased, at least a portion of the working kidney would remain, potentially sparing the patient from kidney dialysis several times a week for an indefinite period. 

Removal of only part of the kidney is increasingly the standard treatment for anyone with a stage 1 kidney cancer, which is defined as a tumor less than 7 cm (2.5 inches).  In some cases, it may not be possible to have this type of surgery, even with a small tumor, because of its position within the kidney. 

A partial nephrectomy can be performed either through what's known as an "open" surgery, in which the surgeon makes a large enough incision to allow room for operating instruments, or through laparoscopy, in which much smaller instruments are placed through a tiny incision. A third option is robotic partial nephrectomy, in which a surgeon manipulates robotic arms into precise micro-movements within the surgical area. 

Cryoablation

Cryoablation refers to freezing of the tumor. This technique is appropriate for treating tumors as large as 5 cm, although the best results are achieved when treating tumors 3 cm or less. Cryotherapy is performed by a laparoscopic technique. The tumor is exposed and all other organs in the area are moved away, so as to not be damaged. To freeze the cancer, special thin probes called cryoablation needles are placed into the tumor. 

Argon gas is delivered under pressure into a small chamber inside the tip of the needle where it expands and cools, reaching a temperature well below -100º Celsius. This produces an iceball of predictable size and shape around the needle. This iceball engulfs the tumor, killing the cancerous cells as well as a small margin of surrounding tissue while sparing healthy kidney structures.  A double freeze-thaw cycle is favored, since studies suggest that consistently larger areas of cell death are achieved with a double rather than single freeze-thaw cycle.

Ultra-thin thermal sensors may also be placed at the margin of the tumor to monitor tissue temperature and help ensure that the entire tumor is destroyed.  At Pacific Urology, Dr. Hopkins has been performing cryoablation on selected patients for several years, with great success. He is accepting referrals for this highly specialized procedure.   

Radiofrequency Ablation

Radiofrequency ablation kills the cancerous cells by heat. The best candidates are patients with tumors three centimeters or less, located on the back side of the kidney, well away from the bowels and other vital structures. Usually performed under CT guidance, with sedation and local anesthesia, a radiofrequency needle is placed into the tumor.

The needle then opens like a drooping umbrella, and radiofrequency energy passes through the tips of the prongs, heating the tumor to the point where the proteins inside the cells curdle, and the cells die. This technique is the least common one utilized for treating kidney cancer as it has the lowest success rate.

Some patients are too sick to have a general anesthesia, and may be candidates for this particular treatment modality. 

Radical nephrectomy

In cases of a large kidney cancer, a surgeon may be required to perform a radical nephrectomy, or complete kidney removal.

As in a partial nephrectomy, a radical nephrectomy can be performed either through open surgery or through laparoscopy. An open radical nephrectomy is performed through a large incision in the side, chest or abdomen. This approach is preferred for very large tumors which may be invading other structures. 

If the surgeon decides that a laparoscopic approach is feasible, he places a camera through the navel into the abdomen and uses specialized instruments to remove the kidney through very small openings in the skin. There is much less pain from a laparoscopic radical nephrectomy, as well as faster recuperation, shorter hospital stay, less unsightly scarring, and faster return to normal activities. 

Among the most modern technological advancements is the da Vinci Robot, which can be utilized to perform a robotic laparoscopic radical nephrectomy, but this is usually reserved for highly selected cases. A urologist can advise you as to which approach is best for your particular situation.

Radiation therapy, chemotherapy & immunotherapy

Kidney cancer is not very responsive to radiation therapy, and so radiation is not considered a primary treatment. Its role is limited to treatment of painful areas of spread (particularly spread to the bones) or brain.  

Kidney cancer is also not very responsive to standard forms of chemotherapy, so it too is not used as primary treatment. Its role is limited to the treatment of advanced cases, where the cancer has spread to other organs.

Immunotherapies, where drugs are used to stimulate the body's own defense mechanisms to fight the cancer, have been the mainstay of treatment for many years. Agents such as Interferon and Interleukin-2 have been utilized for years, but with very limited success.

Recently the FDA has approved new drugs with novel approaches based on our understanding of how the cancer genes operate. Pacific Urology works closely with our medical oncology specialists to provide the latest approaches to the treatment of advanced disease.