Emory
Physician Sees Cryosurgery As Growing Alternative for Destroying Kidney
Cancer
Emory urologists
are using a new surgical technique -- crysosurgery, or the application
of extreme cold to kill cancerous tissue -- in the treatment of kidney
cancer. The procedure was used at the Emory Clinic for the first time
in October 2001, but the physicians predict that several more procedures
will be performed there in the next several months. Cryosurgery shows
promising results with minimal pain and bleeding, shorter recovery period,
and less expensive costs than traditional approaches, says John Pattaras,
M.D., assistant professor of urology.
"It is a kidney sparing alternative
method that is still investigational, but it spares the patient major
surgery," says Dr. Pattaras, director of the division of Minimally Invasive
Urologic Surgery. "It is justified in older patients with small tumors
and other medical problems. Moreover, older patients have less functioning
kidney tissue and are at more risk for peri-operative complications."
Younger patients with minimal
medical problems would best benefit from a partial nephrectomy – removal
of part of the kidney – Dr. Pattaras says. During the kidney ablation
surgery, a laparoscope inserted through a quarter-inch incision into
the abdomen lets the physician view the organs inside of the abdomen.
The physician also uses an ultrasound device to locate the tumor and
to help guide the cryoprobe.
The cryoprobe, containing
liquid nitrogen, is inserted through a small 1/8- inch incision into
the center of the tumor after a biopsy has been taken. Nitrous oxide
then circulates through the instrument and causes the tip to drop to
a temperature of approximately – 90¼ to –100¼ Celsius. The entire tumor
is frozen, allowed to thaw, then refrozen a second time. The freezing
cycle is completed within 15-20 minutes and the tumor is destroyed within
the two hours of the entire procedure.
"The procedure freezes the
cancer cells and directly kills them," says Dr. Pattaras. "It also indirectly
freezes the blood supply surrounding the tumor, thereby starving the
tumor even if some cells survive. Kidney cells will not regenerate,
so only scar tissue remains."
Cryosurgery patients are
admitted for overnight observation and discharged the next morning.
Normally, patients with open surgery procedures are released in seven
to ten days.
Currently there are not outcome
measures that compare the rate of survivorship or prevention of metastasis
from cryosurgery to those of traditional procedures. Use of the procedure
is too recent and there is not five-year follow up data, Pattaras explains.
Cryosurgery has traditionally
been used on external tumors, such as skin cancers and for retinoblastoma
(childhood cancer of the retina). It is also a favorable option because
it minimizes pain and bleeding, avoids the destruction of surrounding
healthy tissue and is less expensive than traditional methods, Pattaras
says.
The American Cancer Society
estimates that there will be 31,800 new cases of kidney cancers in 2002
and 11,600 deaths. Kidney cancer is the eighth most common cancer in
men and the tenth most common cancer in women.
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