Cryotherapy Can Successfully Treat Small Renal Masses
LONDON—Cryotherapy can be used to treat small renal tumors or masses successfully with relatively low rates of complications and recurrence, a urologist skilled in the technique told attendees here at the Renal and Bladder Cancer 3rd National Conference.
Neil Barber, FRCS, Consultant Urological Surgeon at Frimley Park Hospital, Surrey, UK, spoke about his experience with cryotherapy for renal cancer. Since 2008, he has used this modality to treat 52 patients, 75% of whom had a small malignant mass (4 cm or less). Patients had an average age of 70 years. The typical procedure time was two hours and 20 minutes and no blood transfusions were required. The average hospital stay was one night. Three patients experienced complications: two patients had bleeding, which was managed conservatively, and one had a ureteric injury.
With the incidence of small renal masses (2-4 cm) rising in both men and women, particularly in elderly patients, Dr. Barber said he believes treatment options other than surveillance could reasonably be considered when managing this group of patients.
“Surveillence is the talk of the town [at the moment] when we talk about how to manage small renal masses, and there is increasing evidence that surveillance is a safe option although there are no randomised trials to confirm this.” Data have shown that most of these tumors grow very slowly.
Dr. Barber cited data from the Surveillance, Epidemiology, and End Results (SEER) database showing that up to 75% of patients with small renal masses had malignant small renal masses. Of those that were malignant, about 55% had low-grade malignancy. However, up to 20% of patients had high-grade tumors, with some smaller tumors were already metastatic at presentation.
Treatment options for small renal tumors or masses include nephron-sparing surgery or partial nephrectomy, but these, too, are not without their complications, Dr. Barber said.
Dr. Barber's cryotherapy involves freezing and thawing the renal mass. By using hollow needles, he uses argon to freeze the mass. Ice crystals form inside and outside of cells as well as in the surrounding blood supply. During the thawing stage, helium is placed into the mass. Extracellular fluid re-enters cells, further damaging the mass and causing necrosis in the entire tumor.
Overfreezing can be an issue, and there may be complications with bleeding, he noted. The overall complication rate is 9.4%, but this appears to be less than with radiofrequency ablation. Dr. Barber said he thinks cryotherapy is an important option for patients, particularly elderly patients who have a high incidence of small renal tumors. Cryotherapy is minimally invasive and is associated with rapid hospital discharge, and low complication rates, he said. In addition, it is not very technically demanding for surgeons.