Asymptomatic bacteriuria in candidates for active treatment of renal stones: results from an international multicentric study on more than 2600 patients.

The occurrence of asymptomatic bacteriuria concomitant to urolithiasis is an issue for patients undergoing renal stone treatment. Disposing of a preoperative urine culture is essential to reduce the risk of septic events. The endpoint of the study is to report which characteristics of candidates for renal stone treatment are frequently associated with positive urine culture. 2605 patients were retrospectively enrolled from 14 centers; inclusion criteria were age > 18 and presence of a single renal stone 1-2 cm in size. The variables collected included age, gender, previous renal surgery, comorbidities, skin-to-stone distance, stone size, location, density, presence of hydronephrosis. After a descriptive analysis, the association between continuous and categorical variables and the presence of positive urine culture was assessed using a logistic regression model. Overall, 240/2605 patients (9%) had preoperative bacteriuria. Positive urine culture was more frequent in females, patients with previous renal interventions, chronic kidney disease, congenital anomalies, larger stones, increased density. Multivariate analysis demonstrated that previous renal interventions (OR 2.6; 95% CI 1.9-3.4; p < 0.001), renal-related comorbidities (OR 1.31; 95% CI 1.19-1.4; p < 0.001), higher stone size (OR 1.06; 95% CI 1.02-1.1; p = 0.01) and density (OR 1.00; 95% CI 1.0-1.00; p = 0.02) were associated with bacteriuria; male gender and lower caliceal location were inversely related to it. Beyond expected risk factors, such as female gender, other parameters are seemingly favoring the presence of positive urine culture. The awareness of variables associated with bacteriuria allows to assess which individuals are at increased risk of presenting bacteriuria and reduce the rate of septic complications.

Real-world experience of abiraterone acetate plus prednisone in chemotherapy-naive patients with metastatic castration-resistant prostate cancer: long-term results of the prospective ABItude study.

BACKGROUND: Limited real-world data exist on the effectiveness and safety of abiraterone acetate plus prednisone (abiraterone hereafter) in the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) naive to chemotherapy. Most of the few available studies had a retrospective design and included a small number of patients. In the interim analysis of the ABItude study, abiraterone showed good clinical effectiveness and safety profile in the chemotherapy-naive setting over a median follow-up of 18 months. PATIENTS AND METHODS: We evaluated clinical and patient-reported outcomes (PROs) of chemotherapy-naive mCRPC patients treated with abiraterone as for clinical practice in the Italian, observational, prospective, multicentric ABItude study. mCRPC patients were enrolled at abiraterone start (February 2016-June 2017) and followed up for 3 years; clinical endpoints and PROs, including quality of life (QoL) and pain, were prospectively collected. Kaplan-Meier curves were estimated. RESULTS: Of the 481 patients enrolled, 454 were assessable for final study analyses. At abiraterone start, the median age was 77 years, with 58.6% elderly patients and 69% having at least one comorbidity (57.5% cardiovascular diseases). Visceral metastases were present in 8.4% of patients. Over a median follow-up of 24.8 months, median progression-free survival (any progression reported by the investigators), time to abiraterone discontinuation, and overall survival were, respectively, 17.3 months [95% confidence interval (CI) 14.1-19.4 months], 16.0 months (95% CI 13.1-18.2 months), and 37.3 months (95% CI 36.5 months-not estimable); 64.2% of patients achieved ≥50% reduction in prostate-specific antigen. QoL assessed by Functional Assessment of Cancer Therapy-Prostate, the European Quality of Life 5 Dimensions 3 Level, and European Quality of Life Visual Analog Scale remained stable during treatment. Median time to pain progression according to Brief Pain Inventory data was 31.1 months (95% CI 24.8 months-not estimable). Sixty-two patients (13.1%) had at least one adverse drug reaction (ADR) and 8 (1.7%) one serious ADR. CONCLUSION: With longer follow-up, abiraterone therapy remains safe, well tolerated, and active in a large unselected population.

Efficacy and efficiency of Green-Light XPS 180-watt laser system for benign prostatic enlargement in patients treated with 5α-reductase inhibitors.

OBJECTIVE: Aim of the study was to evaluate efficacy and efficiency of 180-watt Green-Light XPS (GL-XPS) laser photoselective vaporization of the prostate (PVP) in patients under 5-Alpha-Reductase Inhibitors (5ARI) treatment. PATIENTS AND METHODS: A consecutive series of patients with lower urinary tract symptoms due to benign prostatic enlargement treated by PVP with the GL-XPS were enrolled. Patients were divided in two groups according to the chronic use (>6 months) of 5ARI. These two groups were compared on lasing density (kilojoules per prostate volume), vaporization efficiency (prostate volume per lasing time), vaporization power (kilojoules per lasing time), Prostate Specific Antigen (PSA) reduction from baseline, symptom score change from baseline and uroflowmetry parameters improvement. Follow-up was performed at 3, 6 and 12 months with International Prostate Symptom Score, Uroflowmetry parameters and PSA. RESULTS: Overall 193 patients were enrolled. Out of them 87/193 (45%) were on 5ARI treatment. No significant differences were recorded between the two groups at baseline. Median age was 68 years old and median prostate volume was 60 ml. In terms of laser efficiency, no statistically significant differences were recorded in terms of lasing time (25 min vs. 24.5 min; p>0.05); energy used (250 kJ vs. 221 kJ; p>0.05), lasing density (6.8 kJ/ml vs. 6.6 kJ/ml, p>0.05), vaporization efficiency (1.4 ml/min vs. 1.3 ml/min, p>0.05) and vaporization power (9.6 kJ/min vs. 9.4 kJ/min; p>0.05). Finally, no significant differences were also recorded postoperatively in the two groups in terms of PSA reduction, improvement in symptom score and uroflowmetry parameters (p>0.05). CONCLUSIONS: Thirty-seven efficacy and efficiency outcomes were not statistically different between the two groups. 5ARI does not reduce the performance and ability of the 180-watt Green-Light XPS laser system.

RIRS in the elderly: Is it feasible and safe?

BACKGROUND: The aim of this study was to compare the safety and efficacy of RIRS in men ≥65 years to those <65 years. MATERIALS AND METHODS: Patients who underwent RIRS were prospectively collected from March 2013 to March 2014 in 5 European centers. Perioperative outcomes and complications in elderly men were compared with men <65 years. Univariable and multivariable analyses were performed for factors predicting overall complications. The groups were compared using Mann-Whitney U test. Categorical variables were compared using chi-squared test and the Yates correction or the Fisher's exact test. RESULTS: A total of 399 patients with renal stones were included, 308 (77.19%) were aged <65 years, 91 (22.8%) were aged ≥65 years. Elderly patients were more likely to have higher ASA scores (35.7% vs 92.3%; p < 001), Charlson Comorbidity Index (1.8 vs. 5.2, p < 0.001), hyperlipidemia (10.06% vs. 30.76%; p = 0,0005) and coronary heart disease (5.51% vs. 17.58; p = 0.005) compared to younger cohort. Perioperative outcomes (stone free rate, operative time and re-intervention rate) did not show differences between the two groups (p > 0.05). Surgical and medical complication rates were similar between the cohorts (14.28% vs 9.89%; p = 0.38). Multivariate analysis did not identify any predictive factors of complications among the two groups (p > 0.05). CONCLUSIONS: In this study, elderly RIRS patients had comparable short term efficacy and perioperative complications to younger patients, despite a higher prevalence of comorbidity. Age itself should not be considered as a risk factor for the development of complications in patients undergoing RIRS for renal stone.

The surgical experience influences the safety of retrograde intrarenal surgery for kidney stones: a propensity score analysis.

The aim of this study is to evaluate if surgical experience could influence the outcomes of retrograde intrarenal surgery (RIRS) in terms of stone clearance and complication rate. Patients from five institutions were included in this study. Patients were divided into two groups. Group 1: patients treated by three surgeons in the early phase of learning curve (surgical experience <100 procedures); Group 2: cases operated by two surgeons with great endourological experience (>400 procedures). Patients and stone characteristics, outcome and complications were analyzed. Multivariable regression model was used. Differences between groups were estimated using propensity scores to adjust for the bias inherent to the different characteristics. 381 RIRS were analyzed (Group 1: 150 RIRS; Group 2: 231 RIRS). Clinical data and stone parameters were comparable. The SFR was 70 % in Group 1 and 77.9 % in Group 2 (p = 0.082). Operative time was significantly shorter in the Group 2 (76.3 vs. 53.1 min, p = 0.001). The overall complication rate was significantly lower in Group 2 (20.7 vs. 8.7, p = 0.001). At unadjusted analysis, a non-significant difference was found between centers on SFR (OR 1.51 95 % CI 0.95-2.41). Conversely, a significant difference was found on overall complications (OR 0.36 95 %CI 0.20-0.67) with lower overall complication in Group 2. This study shows that surgeon experience influences the outcomes of RIRS mainly in terms of safety. Further studies will be needed to assess the exact number of procedures necessary to obtain a plateau in the rate of complications and success.

Trends in the use of partial nephrectomy for cT1 renal tumors: Analysis of a 10-yr European multicenter dataset.

AIM: Although extensively addressed in US registries, the utilization rate of Partial Nephrectomy has been poorly addressed in European settings. Our aim is to evaluate the impact of hospital volume on the use of PN for cT1 renal tumors. METHODS: 2526 patients with cT1N0M0 renal tumors treated with either PN or radical nephrectomy at 10 European centres in the last decade were included in the analysis. Joinpoint regression analysis was used to identify significant changes over time in linear slope of the trend for each center. The correlation between yearly caseload and the slopes was assessed with the non-parametric Spearman test. Coincident pairwise tests and regression analyses were used to generate and compare the trends of high-volume (HV), mid-volume (MV) and low-volume (LV) groups. RESULTS: Yearly caseload was significantly associated with increased use of PN (R = 0.69, p = 0.028). The utilization rate of PN was stable at LV centres (p = 0.67, p = 0.7, p = 0.76, for cT1, cT1a, and cT1b tumors, respectively), while increased significantly at MV (p = 0.002, 0.0005 and 0.007, respectively) and HV centers (all p < 0.0001). Regression analysis confirmed the trends for HV and MV as significantly different from those observed in LV centres (all p ≤ 0.002) and highlighted significant differences also between MV and HV centres (all p ≤ 0.03). CONCLUSIONS: We confirmed the association between caseload and the use of PN for cT1 tumors. Our findings suggest that a minimum caseload might turn the tide also in LV centres while a selective referral to HV centers for cT1b tumors should be considered.

Do we need new high-risk criteria for surgically treated renal cancer patients to improve the outcome of future clinical trials in the adjuvant setting? Results of a comprehensive analysis based on the multicenter CORONA database.

BACKGROUND: Since there is still an unmet need for potent adjuvant strategies for renal cancer patients with high progression risk after surgery, several targeted therapies are currently evaluated in this setting. We analyzed whether inclusion criteria of contemporary trials (ARISER, ASSURE, SORCE, EVEREST, PROTECT, S-TRAC, ATLAS) correctly identify high-risk patients. METHODS: The study group comprised 8873 patients of the international CORONA-database after surgery for non-metastatic renal cancer without any adjuvant treatment. Patients were divided into potentially eligible high-risk and assumable low-risk patients who didn't meet inclusion criteria of contemporary adjuvant clinical trials. The ability of various inclusion criteria for disease-free survival (DFS) prediction was evaluated by Harrell's c-index. RESULTS: During a median follow-up of 53 months 15.2% of patients experienced recurrence (5-year-DFS 84%). By application of trial inclusion criteria, 24% (S-TRAC) to 47% (SORCE) of patients would have been eligible for enrollment. Actual recurrence rates of eligible patients ranged between 29% (SORCE) and 37% (S-TRAC) opposed to <10% in excluded patients. Highest Hazard Ratio for selection criteria was proven for the SORCE-trial (HR 6.42; p < 0.001), while ASSURE and EVEREST reached the highest c-index for DFS prediction (both 0.73). In a separate multivariate Cox-model, two risk-groups were identified with a maximum difference in 5-year-DFS (94% vs. 61%). CONCLUSION: Results of contemporary adjuvant clinical trials will not be comparable as inclusion criteria differ significantly. Risk assessment according to our model might improve patient selection in clinical trials by defining a high-risk group (28% of all patients) with a 5-year-recurrence rate of almost 40%.

Splenogonadal fusion mimicking a testis tumor.

The presence of ectopic splenic tissue in the scrotum is attributed to splenogonadal fusion, a rare congenital anomaly. This ectopic splenic tissue can be an incidental finding or less often present as a scrotal mass later in adult life. Given the rarity of splenogonadal fusion, especially in the adult population, this case highlights the clinical characteristics of the condition, with a special focus on the signs and findings that might help prevent unnecessary orchiectomy.

[Postoperative prognosis of chromophobic renal cell carcinoma: comparative analysis of the multinational CORONA database]. / Die postoperative Prognose des chromophoben Nierenzellkarzinoms : Eine vergleichende Analyse anhand der multinationalen CORONA-Datenbank.

BACKGROUND: The chromophobe subtype represents the third most common histological subtype of renal cell carcinoma (chRCC). Due to the rarity of this subtype only one publication regarding the specific analysis of clinical and histopathological criteria as well as survival analysis of more than 200 patients with chRCC is known to date. MATERIALS AND METHODS: A total of 6,234 RCC patients from 11 centres who were treated by (partial) nephrectomy are contained in the database of this multinational study. Of the patients 259 were diagnosed with chRCC (4.2 %) and thus formed the study group for this retrospective investigation. These subjects were compared to 4,994 patients with a clear cell subtype (80.1 %) with respect to clinical and histopathological criteria. The independent influence of the chromophobe subtype regarding tumor-specific survival and overall survival was determined using analysis by Cox proportional hazards regression models. The median follow-up was 59 months (interquartile range 29-106 months). RESULTS: The chRCC patients were significantly younger (60 vs. 63.2 years, p < 0.001), more often female (50 vs. 41 %, p = 0.005) and showed simultaneous distant metastases to a lesser extent (3.5 vs. 7.1 %, p = 0.023) compared to patients with a clear cell subtype. Despite a comparable median tumor size a ≥ pT3 tumor stage was diagnosed in only 24.7 % of the patients compared to of 30.5 % in patients with a clear cell subtype (p = 0.047). In addition to the clinical criteria of age, sex and distant metastases, the histological variables pTN stage, grade and tumor size showed a significant influence on tumor-specific and overall survival. However, in the multivariable Cox regression analysis no independent effect on tumor-specific mortality (HR 0.88, p = 0.515) and overall mortality (HR 1.00, p = 0.998) due to the histological subtype was found (c-index 0.86 and 0.77, respectively). CONCLUSIONS: Patients with chRCC and clear cell RCC differ significantly concerning the distribution of clinical and histopathological criteria. Patients with chRCC present with less advanced tumors which leads to better tumor-specific survival rates in general; however, this advantage could not be verified after adjustment for the established risk factors.

Analysis of radical cystectomy and urinary diversion complications with the Clavien classification system in an Italian real life cohort.

INTRODUCTION: Standardized methods of reporting complications after radical cystectomy (RC) and urinary diversions (UD) are necessary to evaluate the morbidity associated with this operation to evaluate the modified Clavien classification system (CCS) in grading perioperative complications of RC and UD in a real life cohort of patients with bladder cancer. MATERIALS AND METHODS: A consecutive series of patients treated with RC and UD from April 2011 to March 2012 at 19 centers in Italy was evaluated. Complications were recorded according to the modified CCS. Results were presented as complication rates per grade. Univariate and binary logistic regression analysis were used for statistical analysis. RESULTS AND LIMITATIONS: 467 patients were enrolled. Median age was 70 years (range 35-89). UD consisted in orthotopic neobladder in 112 patients, ileal conduit in 217 patients and cutaneous ureterostomy in 138 patients. 415 complications were observed in 302 patients and were classified as Clavien type I (109 patients) or II (220 patients); Clavien type IIIa (45 patients), IIIb (22 patients); IV (11 patients) and V (8 patients). Patients with cutaneous ureterostomy presented a lower rate (8%) of CCS type ≥IIIa (p = 0.03). A longer operative time was an independent risk factor of CCS ≥III (OR: 1.005; CI: 1.002-1.007 per minute; p = 0.0001). CONCLUSIONS: In our study, RC is associated with a significant morbidity (65%) and a reduced mortality (1.7%) when compared to previous experiences. The modified CCS represents an easily applicable tool to classify the complications of RC and UD in a more objective and detailed way.

Collecting system invasion and Fuhrman grade but not tumor size facilitate prognostic stratification of patients with pT2 renal cell carcinoma.

PURPOSE: The 7th edition of TNM for renal cell carcinoma introduced a subdivision of pT2 tumors at a 10 cm cutoff. In the present multicenter study the influence of tumor size as well as further clinical and histopathological parameters on cancer specific survival in patients with pT2 tumors was evaluated. MATERIALS AND METHODS: A total of 670 consecutive patients with pT2 tumors (10.4%) of 6,442 surgically treated patients with all tumor stages were pooled (mean followup 71.4 months). Tumors were reclassified according to the current TNM classification, and subdivided in stages pT2a and pT2b. Cancer specific survival was analyzed using the Kaplan-Meier method, and univariable and multivariable analyses were used to assess the influence of several parameters on survival. RESULTS: Tumor size continuously applied and subdivided at 10 cm or alternative cutoffs did not significantly influence cancer specific survival. In addition to N/M stage, Fuhrman grade and collecting system invasion also had an independent influence on survival. Integration of a dichotomous variable subsuming Fuhrman grade and collecting system invasion (grade 3/4 and/or collecting system invasion present vs grade 1/2 and collecting system invasion absent) into multivariate models including established prognostic parameters resulted in improvement of predictive abilities by 11% (HR 2.3, p <0.001) for all pT2 cases and 151% (HR 3.1, p <0.001) for stage pT2N0M0 cases. CONCLUSIONS: Tumor size did not have a significant influence on cancer specific survival in pT2 tumors, neither continuously applied nor based on various cutoff values. To enhance prognostic discrimination, multifactorial staging systems including pathological features should be implemented. The prognostic relevance of the variable subsuming Fuhrman grade and collecting system invasion should be considered for future evaluation.

[The LESS (Laparo-endoscopic Single-Site) procedure in urology. Technical and clinical aspects]. / La chirurgia laparoendoscopica con singola incisione in urologia. Aspetti tecnici e clinici.

BACKGROUND: Minimally invasive urology is rapidly advancing, and single-site laparoscopic surgery is being explored clinically. Such laparoscopic procedures are technically challenging and require an experienced laparoscopic surgeon due to the lack of port placement triangulation and instrument clashing. METHODS: In the last years several surgeons all over the world have explored the feasibility and safety of LESS using several and different ports, approaches and devices. Hundreds of procedures have been described with overall favorable intraoperative and postoperative outcomes. RESULTS: Our experience consists of more than 30 procedures successfully completed for adrenal, kidney disease and varicocele. CONCLUSIONS: To date, LESS could be considered feasible and effective using currently available devices, however it is to be considered as an initial status technique requiring further confirmatory studies and advanced laparoscopic skills.

Urological applications of N.O.T.E.S.

While adrenal and kidney urological surgery has been performed in animal models mainly by transvesical accesses, to date, NOTES in humans remains in an investigational and developmental phase. Despite great experimental interest, no specific devices are currently available for urological indications in humans and therefore several instruments, taken from different specialist fields, have been used to access through the different natural orifices (including transgastric, transcolonic, transvaginal and transvesical approaches). Furthermore, the accumulating experience with the transvesical approach to the peritoneum suggests it presents new challenges for urologists in terms of technical demands. For these reasons, given their competition with the success of laparoscopy and minimally invasive techniques, NOTES applications in urology risk being underevaluated. In our opinion, after the initial enthusiastic phase, NOTES will cover only specific indications for urological conditions. The transvesical approach to the peritoneum however seems to be one of the best approaches for NOTES overall and certainly the most promising for urologists.

CD10 is a diagnostic and prognostic marker in renal malignancies.

AIMS: To determine the diagnostic and prognostic value of CD10 immunoreactivity in renal cell carcinomas (RCCs) and transitional cell carcinomas (TCCs). METHODS AND RESULTS: CD10 expression was investigated in primary (n = 180) and metastatic (n = 58) RCCs and upper urinary tract TCCs (n = 53) using a tissue microarray technique. One hundred and fifty-four of 172 (90%) evaluable primary and 48/56 (86%) evaluable metastatic RCCs expressed CD10. Extensive immunoreactivity (positivity of >50% cancer cells) decreased with rising tumour grade in conventional RCCs [G1/G2 72/81 (89%), G3/G4 33/48 (69%); P = 0.009]. Chromophobe RCCs showed a significantly lower overall and extensive immunoreactivity compared with conventional tumours (P < 0.001). In papillary RCCs immunoreactivity of more than 10% of cancer cells for CD10 was seen more often in type 2 (7/8, 88%) compared with type 1 (5/12, 42%; P =0.054) tumours. In conventional RCCs, pure apical membranous staining was associated with low tumour stage (P = 0.003), low grade (P = 0.004) and improved prognosis on univariate analysis (P = 0.031). TCCs were less frequently stained (51%). Extensive staining, however, was associated with high-stage tumours (P = 0.024), high-grade (P = 0.073) tumours, and was associated with shorter disease-free survival in univariate analysis (P = 0.003). CONCLUSIONS: CD10 proved to be an additional marker for renal malignancies with predominantly diagnostic potential.

Are heterogenous results of EGFR immunoreactivity in renal cell carcinoma related to non-standardised criteria for staining evaluation?

AIMS: To assess whether heterogeneity of epidermal growth factor receptor (EGFR) immunoreactivity in renal cell carcinoma (RCC) is related to non-standardised criteria for staining evaluation. METHODS: EGFR expression was investigated in 132 primary and 55 metastatic conventional RCCs using a tissue microarray technique. RESULTS: Overall, membranous and/or cytoplasmic EGFR immunostaining was present in 123 of 132 (93%) primary and 49 of 53 (92%) metastatic RCCs, with extensive immunoreactivity (> 50% of tumour cells) in 110 of 132 (83%) primary tumours and 39 of 53 (73%) metastases. Cytoplasmic staining was associated with high tumour stage and high tumour grade. In addition, strong membranous staining (score 3+) prevailed in high grade RCCs. Cytoplasmic immunostaining was associated with an unfavourable prognosis, whereas overall (cytoplasmic and membranous) immunoreactivity and intensity of membranous staining were not. CONCLUSIONS: Different methods of immunohistochemical evaluation led to different results, strengthening the need for standardisation, especially against a background of rapidly evolving EGFR targeted cancer treatment strategies.

Angiomyolipoma with a caval thrombus.

We report the case of a female patient presenting with flank pain. Abdominal ultrasound revealed a tumor of 8 cm in diameter. After abdominal computerized tomography, the tumor was classified as angiomyolipoma with a tumor thrombus in the inferior vena cava. After nephrectomy, the diagnosis was confirmed histologically. To our knowledge, this is the 11th case of a renal angiomyolipoma extending into the vena cava.

Handicap of walking by a huge paratesticular liposarcoma.

We describe the case of a 71-year-old male with a huge left-sided paratesticular tumour, whose walking was increasingly handicapped by this vast mass. Two palliative excisions of tumour tissue were performed. Histology revealed a poorly differentiated paratesticular liposarcoma. The patient achieved satisfying mobility for several months before he died of cachexia.

Value of transrectal ultrasound in preoperative staging of prostate cancer.

BACKGROUND: The aim of the study was to compare preoperative transrectal ultrasound findings with final histopathological stage after radical prostatectomy to determine the value of TRUS in preoperative staging of prostate cancer. METHODS: The evaluation was performed as a retrospective study. In 114 radical prostatectomy specimens the histopathological, ultrasound and rectal digital findings were correlated. Mean age of patients was 63 years and in all patients a radical retropubic prostatectomy was performed. RESULTS: Organ confined PC was found correctly with TRUS in 68% and capsular penetration in 32%. Corresponding findings with digital rectal examination (DRE) were 68% and 17% respectively. Sensitivity of TRUS in organ confined PC (T1-2) was 66.1% (DRE 68.5%), specificity 32.6% (DRE 20%) and positive predictive value 55.7% (DRE 49.3%). Sensitivity, specificity and positive predictive value of TRUS for stage T3 (a,b,c) were 32.6%, 68.4% and 45.5% respectively. A separate evaluation of stage T3c revealed for TRUS: sensitivity 41.2%, specificity 81.8% and positive predictive value 36.8%. CONCLUSION: On the basis of this retrospective analysis, and due to the low sensitivity and specificity, TRUS is not suitable for adequate preoperative staging of prostatic cancer.

The use of polydimethylsiloxane in the treatment of incontinence after radical prostatectomy.

OBJECTIVE: To report the results of transurethral submucosal injection therapy of polydimethylsiloxane (PDS) to treat incontinence after radical prostatectomy (RP). PATIENTS AND METHODS: Since 1993, about 80 retropubic RPs have been carried out at our institution each year. Severe post-operative incontinence occurred in six patients, with a mean duration of incontinence after RP of 28 months. The pre-operative evaluation consisted of cysto-urethroscopy and urodynamics. Because we have no experience with artificial sphincter implantation, transurethral injection therapy was used to treat the post-operative incontinence, using PDS (vulcanized silicone rubber particles). This material has a mean particle size of 188 microns, providing stability of the material at the injection site. The six patients with severe post-operative incontinence were treated using injection therapy with PDS. RESULTS: After a mean follow up of 15.5 months, five patients, who suffered from day and night incontinence and required at least five pads per day, were dry after injection therapy. One patient improved significantly but still required two pads during the day, but was continent during the night; three patients required a second injection. A mean of 7.5 mL of PDS was used per patient and the side-effects of therapy (dysuria and urinary retention) were minimal. CONCLUSION: Because PDS has excellent biocompatibility, few side-effects or complications, transurethral injection therapy using silicone particles is a justifiable procedure for treating incontinence after RP.