There was an error made in recruitment therefore patients were not randomized correctly. This was identified in February 2012 and the study was cancelled.

The objective of this study is to assess whether using a different type of suture (barbed sutures) during partial nephrectomy results in fewer postoperative complications than with traditional sutures (non-barbed). The most common complications are urine leakage and bleeding. The investigators believe the barbed suture is less technically difficult to use and will allow the surgeon to better repair the hole left in the kidney after the tumor is removed.

With the increased use of radiographic imaging for abdominal complaints the incidental finding of small asymptomatic renal masses has increased. Partial nephrectomy has become the gold standard therapy for treatment of kidney masses ≤7cm in size. Absolute indications for partial nephrectomy include bilateral renal tumors, systemic condition affecting renal function, chronic renal insufficiency and solitary kidney function. Elective indications include masses ≤7cm and normal contralateral kidney function. The procedure can be completed through either laparoscopic or open technique. Complication rates from open and partial nephrectomy have been reported to be about 16% with the most common being urinary leak, postoperative bleeding, renal insufficiency and the need for dialysis.

A major predictor of postoperative complications is the warm ischemia time. This is the length of time the kidney is without blood flow at body temperature. It has been reported that renal and cellular damage of the nephron begins after 20-30 minutes of ischemia. As well, the volume of estimated blood loss has been shown to be a major predictor of postoperative complications. A threshold value of estimated blood loss >750 mL and warm ischemia time >45 minutes have been associated with significantly increased rates of postoperative complications. Recent advancements in laparoscopic technique have lead to the development of the early unclamping method of partial nephrectomy. In this method the renal pedicle is unclamped following the initial central running suture but before the defect has been entirely repaired with bolstering sutures. This method has been reported to decrease warm ischemia time by ≥50% in comparison to the traditional technique of unclamping after full closure of the defect.

The investigators have demonstrated the safety of the "Quill" (Angiotech, Vancouver, BC) polydioxanone barbed self retaining sutures in a retrospective series. These sutures contain unidirectionally oriented barbs on the surface that switch direction at the half-way point. Laparoscopic partial nephrectomy is a technically demanding procedure and maintaining tension during intracorporeal suturing is particularly challenging. The barbs of the self retaining sutures lock into the tissue allowing the surgeon to preserve tissue approximation without needing to maintain tension. The investigators believe these sutures will allow the surgeon to obtain greater tissue approximation therefore decreasing postoperative urinary leakage and bleeding. These findings need to be validated postoperatively.

The investigators believe that coupling the shorter warm ischemia time of the early unclamping method and the greater tissue approximation afforded by the self retaining sutures will result in fewer complications following partial nephrectomy.

Inclusion Criteria:

• any person who is being treated for kidney cancer with partial nephrectomy.

Exclusion Criteria:

• those from whom we cannot obtain adequate informed consent.
• those that are converted from partial to radical nephrectomy intraoperatively.