Renal cancer occurs in nearly 10 of every
100,000 people in the United States and in approximately 45 of every
100,000 of those over 65 years of age. Standard treatment is open
surgery, often involving total removal of the tumor along with the
kidney. However, a study in the September issue of the Journal of
Ultrasound in Medicine reports that ultrasound-guided renal
cryoablation is a feasible technique for treating renal malignancies
while still preserving the renal parenchyma.
Sparing Renal Tissue
Harry G. Zegel, MD, and coauthors from theAllegheny University
Hospitals in Pennsylvania and Urology Specialists of Coastal Georgia
write, "Recent advances in cross-sectional imaging (ultrasound,
MRI, CT) have led to increased detection of small, asymptomatic renal
tumors. Also, in selected cases, patients undergoing partial
nephrectomy have been reported to have rates of survival similar to
those of patients undergoing radical nephrectomy. This has led some
physicians to question the need for radical nephrectomy in patients
with small lesions. While partial nephrectomy spares the maximal
amount of functioning renal tissue, and often eliminates or postpones
the need for dialysis, this technique is associated with risks.
Hence, better kidney tissue-sparing techniques may be of benefit in
The study examined the feasibility of using ultrasound-guided
cryosurgery to treat selected patients with renal malignancy by
studying the technique in six patients with renal tumors.
Benefits of Intraoperative Ultrasonography
In the study, intraoperative ultrasonography accurately delineated
tumor size, cryoprobe placement, and depth of freezing in all
patients. In addition, intraoperative ultrasonography identified a
total of nine additional lesions in three patients that had not been
detected by preoperative imaging. The patients have been followed
with clinical and laboratory assessments, as well as MRI or CT
imaging, and all were tumor-free 3 to 22 months, postoperatively.
In conclusion, the authors write, "we conclude that cryoablation
with intraoperative ultrasonographic guidance is a promising new
technique for treating renal masses while preserving renal parenchyma
and function. Long-term follow-up in a larger series of patients with
biopsy-proved lesions is necessary to determine the true efficacy and
safety of this procedure."