Nephron-sparing surgery (NSS) for renal parenchymal tumours, first documented in the late 19th century [1,2], has developed during the last 10–20 years to become an established technique. Currently the indications for NSS can be divided into three groups, including absolute or imperative, relative, and elective indications. Partial nephrectomy should be considered in all cases of localized malignancy in which a radical nephrectomy would render the individual functionally anephric and requiring renal-replacement therapy. Relative indications include selected patients in whom the contralateral kidney is potentially at risk due to coexisting medical conditions. Elective partial nephrectomy, where the contralateral kidney is normal, is a valid option for renal cell tumours of ≤ 4 cm in diameter [3–5]. Irrespective of the indication, partial nephrectomy is associated with low morbidity, low local recurrence rates and good preservation of renal function [6,7].
Several methods have been described to overcome the problem of haemostasis after resecting a tumour by partial nephrectomy [8–11]. Any attempt to reconstitute the kidney after tissue excision is hampered by sutures cutting through the fragile renal parenchyma once the circulation is restored. Previously, in our department, haemostasis for polar amputations was secured by reconstitution using PTFE pledgeted sutures. Herein we describe a modification of this technique using a natural acellular biomaterial derived from porcine dermis (PelvicolTM, CR Bard Inc., Covington, GA, USA).
The kidney is usually approached via a transperitoneal incision. Gerota's fascia is opened and the renal capsule and hilar vessels exposed, with careful delineation of the tumour extent. The renal artery is clamped and hypothermia instituted with frozen saline slush. The tumour is carefully excised using sharp dissection. Visible arcuate vessels are ligated and if necessary the collecting system repaired. Two (2 × 7 cm) pieces of Pelvicol are placed circumferentially around the cut edges of the renal capsule and two stay sutures placed at either end to hold the biomaterial in place. Haemostatic horizontal mattress polydioxanone sutures are placed along the Pelvicol
Pelvicol (Fig. 1) contains tiny perforations, at sites of previous hair follicles, which can be used to facilitate passage of the round-bodied needle. The sutures are then tied with minimal tension. After restoring the circulation the swelling of the renal substance provides tamponade of any residual bleeding vessels.
ADVANTAGES AND DISADVANTAGES
Pelvicol was designed for implantation in humans and is licensed for use as a sling material in vaginal wall repair, Peyronie's disease and fistula repair. It is manufactured as a completely acellular tissue, which is very close in structure to human collagen. The collagen is also cross-linked and therefore retains strength and is permanent. It is rapidly colonized and re-vascularized by host cells, but induces no inflammatory response. It has so far been shown to persist with no resorption for up to 3 years after implantation [12,13].
COMPARISON WITH OTHER METHODS
The last three partial nephrectomies within our department were performed using Pelvicol; two were elective and the other an absolute indication for partial nephrectomy. There was no difference in operative duration and all three patients had their tumour excised with <30 min of cold ischaemia. The mean operative duration using Pelvicol was 2.1 h, compared to 2.25 h for the previous three partial nephrectomies using the PTFE pledget technique. Unfortunately, exact operative blood loss was not documented for all cases. However, none of the patients required a blood transfusion and comparison of the haemoglobin level before and 1 day after surgery showed a similar decrease (3.2 g/dL for the pledget technique, 3.4 g/dL for Pelvicol). All patients were discharged home within 7 days of surgery with no complications and normal serum creatinine levels.
This technique has advantages over others in that Pelvicol is a natural biomaterial that induces no immune or inflammatory host reaction, and in the event of infection is adequately treated by antibiotics with no need to consider removing the infected synthetic material. It is also our experience that this technique is easier to use than the previously used PTFE pledgets when closing polar-amputation partial nephrectomies.