All three scoring systems demonstrated reliability among observers and represent novel methods of quantitatively describing renal tumors. They were all associated with WIT, percent change in creatinine level, and tumor size. They did not, however, correlate with any other perioperative parameters investigated. At this time, these SS provide a common language for describing renal tumors.

E 2 3 5What ' s known on the subject? and What does the study add? Off-clamp laparoscopic partial nephrectomy (LPN) is thought to preserve renal function by limiting warm ischaemia time (WIT) and consequently reperfusion injury. To date, studies using the off-clamp technique represent a heterogeneous group, with limited follow-up showing feasibility and safety in a restricted number of cases.We report the largest experience of off-clamp vs on-clamp LPN with perioperative outcomes and intermediate follow-up of renal functional outcomes with stratifi cation by WIT. OBJECTIVE• To evaluate perioperative and 6-month renal functional outcomes of patients undergoing off-clamp vs complete hilar control laparoscopic partial nephrectomy (LPN). PATIENTS AND METHODS• A retrospective review of 489 patients undergoing LPN was completed.• Preoperative imaging assessed tumour characteristics.• Patient demographics, perioperative parameters, and postoperative outcomes were documented.• Multivariable regression analysis was used to assess factors contributing to changes in postoperative renal function between off-clamp and clamped LPN. RESULTS• In all, 289 LPNs were performed on-clamp and 150 were performed off-clamp.• Tumours in the on-clamp group were larger than those in the off-clamp group • Univariable analysis comparing off-clamp to on-clamp cohorts showed that estimated glomerular fi ltration rate (eGFR) was better preserved in the off-clamp cohort at 6 months ( − 5.8% vs -11.4%, P = 0.046). Multivariable analysis of the groups showed that estimate blood loss ( P = 0.015) and warm ischaemia time (WIT, P < 0.001) were the only signifi cant predictors of decreased eGFR in the postoperative period.• Difference in eGFR at 6 months was not signifi cant when WIT was limited to 30 min. The complication rate was greater in the clamped cohort (10% vs 20%, P = 0.012).• There was no difference in transfusion rate or positive margin status. CONCLUSIONS• LPN without hilar clamping is feasible, safe and associated with less renal injury as assessed by postoperative GFR in select patients.• With experience, it can be applied to complex renal lesions. KEYWORDSrenal cell carcinoma , renal ischemia , laparoscopic partial nephrectomy , ischaemia-reperfusion injury

The objective of this review is to explore the available literature on solid renal masses (SRMs) in transplant allograft kidneys to better understand the epidemiology and management of these tumors. A literature review using PubMed was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology. Fifty-six relevant studies were identified from 1988 to 2015. A total of 174 SRMs in 163 patients were identified, with a mean tumor size of 2.75 cm (range 0.5-9.0 cm). Tumor histology was available for 164 (94.3%) tumors: clear cell renal cell carcinoma (RCC; 45.7%), papillary RCC (42.1%), chromophobe RCC (3%), and others (9.1%). Tumors were managed by partial nephrectomy (67.5%), radical nephrectomy (19.4%), percutaneous radiofrequency ablation (10.4%), and percutaneous cryoablation (2.4%). Of the 131 patients (80.3%) who underwent nephron-sparing interventions, 10 (7.6%) returned to dialysis and eight (6.1%) developed tumor recurrence over a mean follow-up of 2.85 years. Of the 110 patients (67.5%) who underwent partial nephrectomy, 3.6% developed a local recurrence during a mean follow-up of 3.12 years. The current management of SRMs in allograft kidneys mirrors management in the nontransplant population, with notable findings including an increased rate of papillary RCC and similar recurrence rates after partial nephrectomy in the transplant population despite complex surgical anatomy.