Partial nephrectomy has become a successful form of treatment for patients with localized renal cell carcinoma (RCC) when there is a need to preserve functioning renal tissue. We recently reviewed the long-term results of partial nephrectomy¹ for treatment of sporadic² RCC in 500 patients managed at the Cleveland Clinic prior to 1996. A technically successful operation with preservation of function in the treated kidney was achieved in 489 patients (98%). The five-year cancer specific survival rate³ in the series was 93%, and recurrent RCC developed postoperatively in only 8.2% of patients.

Renal cell carcinoma in von Hippel-Lindau (VHL) differs from sporadic RCC in that the diagnosis is made at a younger age, and there are usually multiple bilateral solid and cystic renal tumors. Studies have shown that partial nephrectomy can provide effective treatment for VHL patients with localized RCC tumors. People with VHL are more likely to have recurring RCC tumors; it is normal in VHL to have multiple tumors on both kidneys. Therefore VHL patients must be followed closely after partial nephrectomy so that any recurrences can be detected at an early stage when they are still localized and amenable to a second renal operation.

Laparoscopic renal cryoablation is an emerging minimally invasive treatment option for selected patients with localized renal cell carcinoma. This involves the use of a freezing probe ("cryo") to remove ("ablate") the diseased portion of the kidney. The aim of cryosurgery is to ablate the same amount of diseased renal tissue that would be removed if conventional surgery excision of the tumor were performed. The targeted diseased renal tissue is rapidly frozen in place ("in situ") with a surrounding margin of healthy renal tissue. The freezing process causes those cells to rupture and die. This devitalized tissue is then allowed to slough off over time, with new tissue forming in its place. The basic process of cryosurgery includes rapid freezing, slow thawing, and a repetition of the freeze-thaw cycle.

A primary advantage of renal cryoablation is that it can be performed laparoscopically without the need for a conventional open surgical incision. The advantages of this approach for treated patients include a shorter hospital stay, less postoperative pain, and a more rapid complete recovery.

Relatively few laparoscopic renal cryoablation procedures have been performed worldwide to date. Our Group at the Cleveland Clinic Foundation reported the initial series of ten patients in 1998,⁴ and our experience now includes more than 40 carefully selected patients with localized RCC. These have all been patients with small (less than 4 cm.) solid, peripheral renal tumors not involving the central renal collecting system.

We recently reviewed our experience with laparoscopic renal cryoablation in the initial 32 patients with localized RCC who met the above criteria. All of these patients had a technically successful operation and there were no significant postoperative complications. The average operative time was 2.0 hours and the average blood loss was 67 cc. Hospital stay was less than 23 hours for most patients and the median time for complete recovery was two weeks. Renal function was preserved in all treated kidneys. Sequential postoperative MRI scans demonstrated a gradual contraction in the size of the treated lesion; in some patients the treated lesion was no longer visible on radiological scans after one year. Twenty-four patients have undergone CT-directed needle biopsy of the cryoablated renal tumor site at six months postoperatively, and these biopsies have all been negative for cancer. There have been no cases of renal fossa or metastatic tumor recurrence with follow-up of up to three years.

Our experience demonstrates that the technique of laparoscopic renal cryoablation is reproducible and technically feasible with a low rate of surgical complications. This approach may be employed to treat VHL patients with a limited number of small (under 4 cm.) solid renal tumors on the outside of the kidney that do not involve the central renal collecting system. Laparoscopic renal cryoablation can be performed as a primary treatment for localized RCC, or for secondary treatment of isolated, small locally recurrent tumors. Notwithstanding the promising early results, longer-term clinical and radiographic follow-up of treated patients is needed to ultimately validate the effectiveness of this new approach.

1. A nephrectomy is removal of a kidney; partial nephrectomy is removal of part of a kidney.

2. Sporadic tumors are ones that occur at random in the general population, as contrasted with tumors that occur due to an underlying familial predisposition such as VHL.

3. Cancer-specific survival rates measure the number of people in the study who died from cancer. Someone for example who died in an automobile accident would not be counted as having died for purposes of this study. Thus after five years, 7% of the people in the study had died of cancer. 8.2% of those in the study had a recurrent RCC tumor, which is not unusual in VHL.

4. Urology (1998) 52:543-551.

As printed in the VHL Family Forum 8:1, March 2000. For permission to reprint, please contact VHL Family Alliance, editor@vhl.org. Further information is available from the VHL Family Alliance, info@vhl.org.