Differentiating reconstructive techniques in partial nephrectomy: a propensity score analysis.

INTRODUCTION: To assess whether volumetric measurements can differentiate functional changes between reconstructive techniques after partial nephrectomy. MATERIALS AND METHODS: One hundred and fifty-six patients undergoing partial nephrectomy for a single renal mass were retrospectively studied between 2008 and 2012. Computed tomography scans were available for volume calculations on 56 (18 non-renorrhaphy and 38 renorrhaphy). Institutional review board approval was obtained. The primary outcome was %volume loss in the operated kidney, which was calculated from three-dimensional reconstructions using a semiautomatic segmentation algorithm. Multivariable regression and propensity score analysis was performed. RESULTS: Volumetric analysis detected a difference in mean %volume loss between two-layer reconstruction (cortical renorrhaphy and base-layer) and base-layer only (15.6% versus 3.8%, p < 0.001). The mean %glomerular filtration rate (GFR) loss was also greater in the two-layer group (8.9% versus 2.4%, p = 0.03). Demographics were similar between groups except the two-layer group was older, had more males, and increased ischemia time. On multivariable regression the presence of two-layer closure (ß = -15.2%, p < 0.001) and tumor diameter (ß = -7.4, p = 0.004) were significant predictors of %volume loss while ischemia time (p = 0.88) was not. Two-layer closure remained a predictor on propensity-adjusted analysis (ß = -14.3, p = 0.004). The base-layer only group had two (5.3%) urine leaks and two (5.3%) bleeding complications. The two-layer group had two (1.7%) urine leaks and three (2.5%) bleeding complications (p = 0.23, 0.41). CONCLUSIONS: Volume loss calculated from CT scans can be used to monitor postoperative renal function. Techniques for renal reconstruction and tumor diameter are associated with volume and functional loss after partial nephrectomy and should be controlled for in future studies.

First 100 cases at a low volume prostate brachytherapy institution: learning curve and the importance of continuous quality improvement.

INTRODUCTION: We report the first 100 patients who underwent prostate brachytherapy as monotherapy with 125I at an institution with moderate volume radical prostatectomy but low volume brachytherapy (<2 cases per month). Learning curve and quality improvement was assessed by way of achieving prescription dose targets. MATERIALS AND METHODS: From May 2002 to August 2006, 100 patients underwent prostate 125I brachytherapy monotherapy via preplanned approach. Preoperative planned dose to 100% of prostate gland (D100) was 145 Gy and postoperative confirmed dose was assessed by computed tomography. The cohort was divided into quartiles and recurrence was assessed using Kaplan-Meier analysis. RESULTS: Patient quartiles were of similar age and Gleason grade, while PSA was slightly higher in the first group. Postoperative D90 increased after the first quartile (p = < 0.0001) reaching targeted values. Kaplan-Meier survival analysis revealed that 5 year recurrence-free survivals by Phoenix definition was 96%-100% in all groups while by ASTRO definition there was a decrease in recurrence for later cases. CONCLUSIONS: At our low volume institution during the first 100 brachytherapy cases, a learning curve for radiation dosimetry was evident, which improved after 25 patients. Preplanned dose-volume parameters were adjusted, enabling the achievement of post-implant goals emphasizing the importance of continuous quality improvement. Although recurrence data is limited by sample size and moderate follow up, there was a discrepancy between the Phoenix and ASTRO definition when evaluating recurrence.