Men are at higher risk than women for being diagnosed with kidney cancer, according to the American Cancer Society. While renal cell carcinoma makes up only 3 percent of all cancers, almost 25 percent of the 54,390 people who are diagnosed with the disease in 2008 will die. Improved screening of at-risk patients and the development of new treatment options, however, can help to increase survival rates in these patients.
Because kidney cancer symptoms — low back pain, a mass or lump in the abdomen, fever, swelling of the ankles and legs — usually do not become apparent until the disease has progressed beyond the initial stages, improved screening of at-risk patients is important, said Clint Holladay, MD, a radiation oncologist at Trinity Medical Center. "Physicians can do a urinalysis to check for blood in the urine, but that's not cost effective to do on all patients," he said. "Plus, the blood can be a symptom of a lot of other things, too."
Holladay said that physicians can use some of the more common risk factors for renal cell carcinoma as a guide for which patients should be monitored. "The number-one indicator for the development of kidney cancer is Von Hippel-Lindau disease. Of the people who have this rare genetic disease, 35 percent will get cancer," he said. "These patients tend to be younger and are more likely to develop the cancer in both kidneys."
Polycystic kidney disease can also increase a person's risk for kidney cancer, along with older age, smoking and obesity. Many studies suggest that exposure to certain chemicals, such as asbestos, cadmium, some herbicides, and organic solvents can also increase the risk of developing the disease.
Kidney cancers are often found incidentally during tests for some other illness, such as gallbladder disease. When the cancer is discovered this way, the survival rate is higher because it is usually at an earlier stage. However, because of the location of the kidneys, most renal cell carcinomas are discovered after they become advanced.
The treatment regimen for kidney cancer is usually based on the size of the tumor, said Lee N. Hammontree, MD, of Urology Centers of Alabama, P.C. Traditional surgery for large tumors includes a radical nephrectomy, which involves the removal of the kidneys as well as the adrenal gland that sits atop the kidney, a border of healthy tissue and adjacent lymph nodes. This surgery can be done through an incision or laparoscopically.
For patients who have early-stage kidney cancer or have only one kidney, nephron-sparing surgery has been the traditional treatment option in which the surgeon removes only the tumor, not the entire kidney. Recovery from both this surgery and the radical nephrectomy can be long and painful.
A new procedure called cryoablation has been developed for the treatment of smaller localized tumors and can effectively kill the tumors on an outpatient basis while offering a faster recovery time. Most patients are sent home the same day as the surgery. According to the Society of Interventional Radiology, cryoablation is 95 percent effective in tumors that are four centimeters or smaller and almost 90 percent effective for tumors up to seven centimeters when the disease is confined to the kidney at the one-year follow up.
During the procedure, the doctor inserts cryotherapy needles and temperature sensors into the kidney through a small incision in the abdomen. The doctor then infuses the tumor with argon gas, which causes a ball of ice to form at the tip of the needle. Once the area reaches the temperature that kills the cancer, the tumor is allowed to thaw slightly with the help of helium gas. This cycle is repeated two more times to ensure that the tumor is completely killed. During the procedure, the blood supply to the tumor is completely cut off, which causes the tumor to die and eventually disappear.
Hammontree was the first surgeon in the region to offer cryosurgery for small kidney tumors, and he has handled more than 100 cases to date. "The recurrence rate for tumors following cryosurgery is 1 to 2 percent. At this point, however, I haven't had a case where a tumor has recurred," he said. "Another plus for this procedure is that in the event of a local recurrence, we can repeat the cryoablation or do a partial nephrectomy because the cryosurgery spares the healthy kidney tissue."
Hammontree follows his cryosurgery patients with a CT scan three months after the procedure and then every six months until he is positive the mass is not going to recur.
"Cryosurgery is one of the most exciting things to come along in a while," he added. "The current standard treatment is laparoscopic partial nephrectomy, but given the continued high success of cryoablation, that may change."
