Prediction of Pathologic Findings with MRI-Based Clinical Staging Using the Bayesian Network Modeling in Prostate Cancer: A Radiation Oncologist Perspective / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#This study aimed to develop a model for predicting pathologic extracapsular extension (ECE) and seminal vesicle invasion (SVI) while integrating magnetic resonance imaging-based T-staging (cTMRI, cT1c-cT3b). @*Materials and Methods@#A total of 1,915 who underwent radical prostatectomy between 2006-2016 met the inclusion/exclusion criteria. We performed a multivariate logistic regression analysis as well as Bayesian network (BN) modeling based on possible confounding factors. The BN model was internally validated using 5-fold validation. @*Results@#According to the multivariate logistic regression analysis, initial prostate-specific antigen (iPSA) (β=0.050, p < 0.001), percentage of positive biopsy cores (PPC) (β=0.033, p < 0.001), both lobe involvement on biopsy (β=0.359, p=0.009), Gleason score (β=0.358, p < 0.001), and cTMRI (β=0.259, p < 0.001) were significant factors for ECE. For SVI, iPSA (β=0.037, p < 0.001), PPC (β=0.024, p < 0.001), Gleason score (β=0.753, p < 0.001), and cTMRI (β=0.507, p < 0.001) showed statistical significance. BN models to predict ECE and SVI were also successfully established. The overall area under the receiver operating characteristic curve (AUC)/accuracy of the BN models were 0.76/73.0% and 0.88/89.6% for ECE and SVI, respectively. According to internal comparison between the BN model and Roach formula, BN model had improved AUC values for predicting ECE (0.76 vs. 0.74, p=0.060) and SVI (0.88 vs. 0.84, p < 0.001). @*Conclusion@#Two models to predict pathologic ECE and SVI integrating cTMRI were established and installed on a separate website for public access to guide radiation oncologists.

The Protein Expressions of Apoptosis-associated Genes in the Obstructed Ureters of Rats / 대한비뇨기과학회지

PURPOSE: The role of apoptosis in the pathogenesis of ureteral damage from obstructive uropathy has rarely been studied. This study was performed to determine the protein expression of the apoptosis-associated genes in the pathogenesis of ureteral damage during the course of obstructive uropathy in ligated rat ureters. MATERIALS AND METHODS: After unilateral ligation of the ureter, each group of five Sprague-Dawley rats was sacrificed and examined at 1, 5, 10, 15, 20, 25, 30 and 35 days after ligation: five rats with normal ureters were also examined as controls. The protein expressions of the fas-associated death domain (FADD), Bax, Bcl-xL and cyclooxygenases (COX)-2 genes in obstructed ureters were assessed by performing Western blotting. RESULTS: The expressions of FADD protein in the 20 and 25 day-obstructed ureters (DOUs) were significantly higher than that in control ureters and the peak was reached in the 25 DOUs. The expressions of Bcl-xL protein in the 20, 25 and 30 DOUs were significantly higher than that in the control ureters and the peak was reached in the 25 DOUs. The expression of COX-2 protein in the 5, 10, 15, 25 DOUs were significantly higher than that in the control ureters and the peak was reached in the 10 DOUs. CONCLUSIONS: The FADD and Bcl-xL genes were involved in apoptosis of the obstructed ureter. The peaks of their expressions were at 25 DOUs. The expression of the COX-2 gene may be related with apoptosis in the obstructed ureter.

The Serial Microscopic Changes of Cell Proliferative and Apoptotic Phenomenon in Obstructed Ureters in the Rat / 대한비뇨기과학회지

Purpose: Obstructive uropathy due to a ureteral obstruction is one of the most common diseases of the urinary tract, and can lead to severe renal injury and ureteral damage. This study performed to elucidate the histological findings and serial changes in the apoptotic and proliferative phenomena in the pathogenesis of ureteral damage during the course of obstructive uropathy in ligated rat ureters. Materials and Methods: After unilateral ligation of the ureter, each group of five Sprague-Dawley rats was sacrificed, and examined 1, 5, 10, 15, 20, 25, 30 and 35 days after ligation: five rats with normal ureters were also examined as controls. The cell proliferation and apoptosis were detected with proliferating cell nuclear antigen (PCNA) immunohistochemistry and a terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) in situ nick-end labeling (TUNEL) study, respectively, in 45 Sprague-Dawley rats. Results: The epithelial layer was thickened in the 5 day-obstructed ureters (DOUs). The severity of thickening of the fibrous and smooth muscle layers progressed consistently to the 15 DOUs, which was maintained until day 35. The expression of PCNA in the epithelial layer was present in every ureter, with a significant increase of labeled cells in the 1 and 5 DOUs. The expressions of PCNA in the fibrous and smooth muscle layers were present from day 10 after ligation and maintained until day 20, but then significantly declined at 25 DOUs. TUNEL-positive cells were shown in the epithelial layer in the 10, 15, 20, 25, 30 and 35 DOUs. The mean numbers of TUNEL-positive cells in the 20, 25 and 30 DOUs were significantly higher than those in the 10 DOUs, and reached their peak in the 25 DOUs. Positive cells were shown in the fibrous and smooth muscle layers in the 25, 30 and 35 DOUs. Conclusions: Apoptosis and cell proliferation may play an important role in the pathogenesis of ureteral damage in obstructed ureters. The peak of apoptosis was shown in the 25 DOUs.

Prophylactic Efficacy of Intravesical Bacillus Calmette-Guerin for High Risk Superficial Bladder Tumor / 대한비뇨기과학회지

A study was performed to determine the prophylactic efficacy of intravesical BCG instillation in 82 patients with high risk superficial bladder tumors. Recurrent, grade III, multiple(more than 3) or large(more than 3cm) stage Ta orT1 tumors were included. They were treated with 6 weekly instillation of 120mg of BCG after transurethral resection. Another thirty six patients treated with transurethral resection alone were selected as a control group. All the patients were followed more than 24 months, with the mean of 32 months. The one year recurrence rate was 54% in BCG group and 74% in controls, which was statistically different(p0.05). The median interval of recurrence from treatment was l4.5 months in the BCG group which was longer than that of 7 months in controls and the recurrence per l00 patient months was 7.86 and l4. 68(p<0.05), respectively. In 56 patients with recurrent tumors after BCG treatment, the tumor stage, grade, number and size of the recurrent tumors were lowered significantly compared to the initial tumors (p<0.05). One patient of the BCG group and 3 of the controls had recurrent tumors with progression to muscle invasion. In summary, BCG instillation improved stage and grade, decreased number and size of the recurrent tumors, and delayed the time of recurrence in patients with high risk superficial bladder tumors. Also the overall one year recurrence rate was significantly improved. but two year recurrence rate was not significantly improved.

A comparison of mitomycin C and bacillus calmette-guerin for the prophylaaxis of high risk superficial bladder tumors / 대한비뇨기과학회지

We compared the prophylactic efficacy of intravesical mitomycin C with bacillus Calmette-Guerin instillation in the high risk superficial bladder tumor patients. Recurrent, grade III multiple (more than 3) or large(more than 3 cm) stage Ta or T1 tumors were included. Thirty patients were treated with 8 weekly instillation of 40mg of mitomycin C and 31 with 6 weekly instillation of 120mg or BCG. Thirty six patients were selected as a control Group. The mean follow-up period was 31.3 months in BCG, 27.7 months in mitomycin C and 23.2 months in control group. The overall one and two year recurrence rate was 52% and 62% in BCG, 70% and 80% in mitomycin C and 74% and 82% in control group. which was not statistically different(p>0.05) and the recurrence free pattern among three groups was not different statistically. But the mean time for recurrence and time for recurrence of 50 percent of the patients was 24.55 and 13 months in BCG group, which were longer than 14.2 and 5 months in mitomycin C and 12.72 and 7 months in control group. The tumor grade and number were lowered in the 20 recurrent tumors after BCG treatment with statistical significance. The overall 2 year recurrence rate was not significantly improved, BCG instillation resulted in improvement in grade, decrease in the number of the tumor and delay in time for recurrence in patients with high risk superficial bladder tumors. Although prophylactic efficacy of the BCG instillation is not complete, it would be provide reasonable benefit to the patients and is apparently superior to mitomycin C.