S.J. Hong

Increased Expression of Matrix Metalloproteinase 9 Correlates with Poor Prognostic Variables in Renal Cell Carcinoma

BACKGROUNDnMMP2 and MMP9 are two gelatinolytic enzymes, which are key regulators of tumor invasion and metastasis. This study aimed to clarify the prognostic significance of MMP2 and MMP9 with particular regard to their transcript levels, enzymatic activities in renal cell carcinomas (RCCs).nnnMATERIALS AND METHODSnThrough cDNA array, the differential expression of the MMP superfamily was evaluated in RCC. Various properties of MMP2 and MMP9 were quantified, in 178 patients with RCC, based on the Heidelberg classification. Of these, 145 cases including 16 fresh-frozen cases were available for MMP2 and MMP9 transcript level evaluation. In addition, gelatinolytic activity was assessed by zymography in 16 other fresh-frozen samples from new RCC cases.nnnRESULTSnMMP2, 9, 11, 14, and 16 were upregulated in the conventional RCC in comparison with the chromophobe RCC, whereas MMP1, 11 and 16 were pronounced in papillary RCC. MMP9 transcript levels were strongly associated with the MMP9 enzymatic activity (p=0.001), and therefore, with disease-free survival (p=0.001) and metastasis (p=0.011). Gelatinolytic activity of MMP9 by zymography was strongly associated with MMP9 mRNA expression, which was more intense in conventional RCC than in chromophobe RCC (p=0.001), irrespective of tumor grade or stage. MMP9 was proven to be a significant prognostic predictor by multi-variate survival analysis (p=0.0054). MMP2 enzymatic activity disappeared in spite of its constant transcript expression in RCC.nnnCONCLUSIONSnMMP9 appears to be regulated at the transcript level, whereas MMP2 is regulated at the posttranscriptional level. Poor survival with a high frequency of metastases in conventional RCC is associated with MMP9, which exhibits a high transcriptional level, and a high gelatinolytic activity. As a result, MMP9 may be a candidate of predictors of disease-free survival in RCC.

A novel mathematical model to predict the severity of postoperative functional reduction before partial nephrectomy: The importance of calculating resected and ischemic volume

PURPOSEnPreoperatively predicting postoperative kidney function is an essential step to achieve improved renal function and prevent chronic kidney disease. We introduce a novel formula especially to calculate resected and ischemic volume before partial nephrectomy. We examined whether resected and ischemic volume would have value for predicting postoperative renal function.nnnMATERIALS AND METHODSnWe performed a retrospective cohort study in 210 patients who underwent robotic partial nephrectomy between September 2006 and October 2013 at a tertiary cancer care center. Based on abdominopelvic computerized tomography and magnetic resonance imaging we calculated resected and ischemic volume by the novel mathematical formula using integral calculus. We comparatively analyzed resected and ischemic volume, and current nephrometry systems to determine the degree of association and predictability regarding the severity of the postoperative functional reduction.nnnRESULTSnOn multivariable analysis resected and ischemic volume showed a superior association with the absolute change in estimated glomerular filtration rate/percent change in estimated glomerular filtration rate (B = 6.5, p = 0.005/B = 6.35, p = 0.009). The ROC AUC revealed accurate predictability of resected and ischemic volume on the stratified event of an absolute change in estimated glomerular filtration rate/event of percent change in estimated glomerular filtration rate compared to 3 representative nephrometry systems. The calibration plot of this model was excellent (close to the 45-degree line) within the whole range of predicted probabilities.nnnCONCLUSIONSnWe report a method of preoperatively calculating resected and ischemic volume with a novel formula. This method has superior correlation with the absolute and percent change in estimated glomerular filtration rate compared to current nephrometry systems. The predictive model achieved a strong correlation for the absolute and percent change in estimated glomerular filtration rate.

Comparison of pathological outcomes of active surveillance candidates who underwent radical prostatectomy using contemporary protocols at a high-volume Korean center.

OBJECTIVEnWe compared contemporary active surveillance protocols based on pathological outcomes in patients who underwent radical prostatectomy.nnnMETHODSnWe identified the experimental cohort from prostate cancer patients who underwent radical prostatectomy between 2001 and 2011, and who met the inclusion criteria of five published active surveillance protocols, namely Johns Hopkins Medical Institution, University of California at San Francisco, Memorial Sloan-Kettering Cancer Center, University of Miami and Prostate Cancer Research International: Active Surveillance. To compare each protocol, we evaluated the pathological outcomes and calculated the sensitivity, specificity and accuracy for each protocol according to the proportion of organ-confined Gleason≤6 disease.nnnRESULTSnOverall, 376 patients met the inclusion criteria of the active surveillance protocols with 61, 325, 222, 212 and 206 patients meeting the criteria of the Johns Hopkins Medical Institution, University of California at San Francisco, Memorial Sloan-Kettering Cancer Center, University of Miami and Prostate Cancer Research International: Active Surveillance protocols, respectively. The sensitivity and specificity values of the five protocols, respectively, were 0.199 and 0.882 in Johns Hopkins Medical Institution, 0.855 and 0.124 in University of California at San Francisco, 0.638 and 0.468 in Memorial Sloan-Kettering Cancer Center, 0.599 and 0.479 in University of Miami, and 0.609 and 0.527 in Prostate Cancer Research International: Active Surveillance. In terms of both the sensitivity and specificity, Prostate Cancer Research International: Active Surveillance was the most balanced protocol. In addition, Prostate Cancer Research International: Active Surveillance showed a more accurate performance for favourable pathological outcomes than the others. However, using the area under the curve to compare the discriminative ability of each protocol, there were no statistically significant differences.nnnCONCLUSIONSnThe contemporary active surveillance protocols showed similar pathological characteristics in patients who had undergone radical prostatectomy. However, we concluded that the Prostate Cancer Research International: Active Surveillance protocol would be most helpful to Korean populations in choosing candidates for active surveillance considering the balance between sensitivity and specificity and the accuracy of diagnosis.

Prognostic impact of preoperative neutrophil-to-lymphocyte ratio after radical prostatectomy in localized prostate cancer

Background:Neutrophil-to-lymphocyte ratio (NLR) has a prognostic value in patients with metastatic castration-resistant prostate cancer receiving systemic therapy. However, the prognostic significance of NLR was never previously evaluated in patients who underwent radical prostatectomy (RP) for prostate cancer. In the present study, we investigated the influence of NLR on survival after a RP for prostate cancer.Methods:We retrospectively reviewed clinical data of 2301 patients with prostate cancer who underwent RP at our institution between 2000 and 2010. Among these patients, we considered only patients who had a preoperative complete blood count with differential result available. Patients who received neoadjuvant or postoperative adjuvant treatment (radiation, androgen deprivation therapy or both) and those without adequate medical record were excluded. A Kaplan–Meier analysis was performed to analyze biochemical recurrence-free survival (BCRFS), overall survival (OS) and prostate cancer-specific survival (CSS). Univariate and multivariate Cox regression models were used for each end point.Results:In total, 2067 patients were evaluated; median follow-up time was 78 months (interquartile range (IQR) 65–96), median age at RP was 66 years (IQR 61–70) and median preoperative NLR was 1.76 (IQR 1.35–2.40). A Kaplan–Meier analysis showed a significant association between high NLR (⩾1.76) and decreased CSS (P=0.005) and OS (P=0.003) but not with BCRFS (P=0.223). In the univariate and multivariate regression analyses, a high NLR was a significant predictor of CSS (hazard ratio (HR) 2.012, 95% confidence interval (CI) 1.222–3.310, P=0.006) and OS (HR 1.650, 95% CI 1.127–2.416, P=0.010).Conclusions:This study shows that in patients with prostate cancer preoperative NLR is an independent prognostic factor for OS and CSS after a RP and suggests that a preoperative hematologic workup should be considered in the risk assessment of these patients.

Clinical values of selective-clamp technique in robotic partial nephrectomy

AbstractPurposenIn the era of robotic partial nephrectomy (RPN), several efforts on improved renal functional outcome have been reported. Selective-clamp is a novel technique that eliminates global ischemia, the clinical value of which needs to be demonstrated. The purpose of this study was to compare the postoperative functional outcomes of patients who underwent selective-clamp and total-clamping RPN.Patients and methodsFrom February 2009 to October 2012, a database of 126 consecutive patients who underwent RPN was retrospectively analyzed, 117 patients met our inclusion criteria and were stratified into two groups, 20 patients underwent selective-clamp RPN, and 97 patients underwent total-clamping RPN. Post hoc power analysis was subsequently performed for calculation of sufficient sample size. Demographics/tumor characteristics, functional outcomes and complications were analyzed.ResultsAll selective-clamp RPN cases were successfully performed. Mean tumor size was 3.4xa0cm [standard deviation (SD): ±1.4], mean RENAL nephrometry score was 7.3 (SD: ±2.0), and no Clavien–Dindo III–V complications were recorded. Selective-clamp RPN group had a significantly lower percentage decrease in the postoperative estimated glomerular filtration rate at 1xa0week (1.8 vs. 20.8xa0ml/min/1.73xa0m2, pxa0=xa00.001) and 3xa0months (0 vs. 9.9xa0ml/min/1.73xa0m2, pxa0=xa00.032) when compared with the total-clamping RPN group. There were no significant differences in surgical margin and complication rates.ConclusionsSelective-clamp confers improved renal functional outcomes in comparison to total-clamping RPN, with acceptable complications and oncological outcomes even in large and complex tumors.

A rare case of interparietal incisional hernia from 8 mm trocar site after robot-assisted laparoscopic prostatectomy.

Trocar site hernia arising from 8xa0mm robotic port is very rare despite the increasing prevalence of robot-assisted surgeries. To date, there had been only a single case reported in the literature. We report a case of small bowel obstruction secondary to an interparietal trocar site incisional hernia after robot-assisted laparoscopic prostatectomy. Meticulous closure of 8xa0mm robotic trocar sites associated with large peritoneal defect at the end of surgery should be performed.