Urinary transforming growth factor beta-1 levels correlate with the effect of renorrhaphy on functional outcomes post-laparoscopic partial nephrectomy: A pilot-study.

Purpose: Preservation of functional renal parenchyma is one of the main targets of partial nephrectomy. We investigated the effects of suture on renal parenchyma in tumor bed and on short-term renal function.

Materials and methods: Patients with unilateral cT1 renal masses candidate for laparoscopic partial nephrectomy (PN) have been recruited. After tumor excision, medullary sutures were replaced by argon beam in Group 1, while Group 2 had conventional 2-layer renorrhaphy. Groups have been matched using propensity score. Transforming growth factor beta-1 (TGFb1) levels in urine have been measured at the 1^st and 30^th day post-PN. Glomerular filtration rate has been estimated (eGFR) at baseline and 3 months post-PN.

Results: Sixteen cases were matched in each group. There was no difference between groups regarding baseline, operative and perioperative data. Number of sutures in group 1 is nearly half that in group 2 (10 vs 19, respectively, p < 0.001). Group 1 showed lower urinary TGFb1 levels at the 1^st and 30^th day post-PN (p < 0.01 for each), higher eGFR after 3 months (p = 0.01), and less decline of eGFR from baseline (p = 0.046).

Conclusion: TGFb1 levels in urine after PN are related to the number of sutures. Reduced number of sutures in tumor bed has a positive effect on short term eGFR changes possibly by reducing tumor bed fibrogenic healing response as well as preserving renal parenchymal volume.