Acute histologic changes in human renal tumors after cryoablation.Acute
histologic changes in human renal tumors after cryoablation.
Edmunds TB Jr, Schulsinger
DA, Durand DB, Waltzer WC.
Department of Urology, State University of New York
at Stony Brook, 11794, USA.
BACKGROUND AND PURPOSE: Cryoablation is a treatment
option for some patients with small, exophytic lesions of the kidney.
Several investigators have evaluated the effects of cryoablation
in normal renal tissue of animals. The purpose of this study was
to investigate the tissue changes following cryoablation in human
renal tumors. PATIENTS AND METHODS: We prospectively evaluated patients
with solid renal lesions (1.5-1.8 cm) confirmed by CT, MRI, or both.
Metastatic work-up for all patients was negative. All lesions were
biopsied prior to freezing. Two patients with bilateral renal tumors
underwent argon-gas-based CRYOcare System (Endocare, Irvine, CA)
treatment via an open approach. A 3-mm cryoprobe was placed directly
into each tumor. A single 15-minute freeze preceded an active thaw
(helium gas) for each lesion. Iceball dimensions were monitored
by intraoperative ultrasonography. After successful cryoablation,
partial nephrectomy was performed to remove the lesion, and the
renal tissue underwent histologic evaluation. RESULTS: The cryoprobes
achieved a temperature of -135 degrees C. No bleeding was noted,
and there were no intraoperative or postoperative complications
with a mean follow-up of 3 months. Histologically, freezing of renal
tissue resulted in coagulative necrosis and hemorrhage beyond the
boundaries of the lesions. There was a zone of demarcation between
the viable and nonviable tissue. CONCLUSIONS: In our series, cryoablation
was effective in destroying tumor tissue in vivo in human kidneys.
Freezing was sufficient to achieve a negative surgical margin. Cryoablation
of renal tumor is an alternative to the currently available nephron-sparing
surgical techniques. The long-term effect of tumor tissue destruction
by cryosurgery requires further investigation.
PMID: 10772505 [PubMed - indexed for MEDLINE]