Apparent diffusion coefficient values obtained by unenhanced MRI predicts disease-specific survival in bladder cancer.

AIM: To assess the ability of apparent diffusion coefficient (ADC) measurements obtained by MRI to predict disease-specific survival (DSS) in patients with bladder cancer and compare it with established clinico-pathological prognostic factors. MATERIAL AND METHODS: The ethical review board approved this cross-sectional study. Patients with suspected bladder cancer receiving diagnostic 3 T diffusion-weighted imaging (DWI) of the bladder before transurethral resection of the bladder (TUR-B) or radical cystectomy were evaluated prospectively. Two independent radiologists measured ADC values in bladder cancer lesions in regions of interest. Associations between ADC values and pathological features with DSS were tested statistically. A combined model was established using artificial neuronal network (ANN) methodology. RESULTS: A total of 51 patients (median age 69 years, range 41-89 years) were included. Three patients were lost to follow-up, leaving 48 patients for survival analysis. Seven patients died during the 795 months studied. ADC showed significant potential to predict DSS (p<0.05). Except for grading, all pathological features as assessed by TUR-B could predict DSS (p<0.05, respectively). The combined ANN classifier showed the highest accuracy to predict DSS (0.889, 95% confidence interval: 0.732-1, p=0.001) compared to all single parameters. ADC was the second important predictor of the ANN. CONCLUSIONS: ADC measurements obtained by unenhanced MRI predicts DSS in bladder cancer patients. A combined classifier including ADC and clinico-pathological information showed high accuracy to identify patients at high risk for disease-related death.

Utility and limitations of 3-Tesla diffusion-weighted magnetic resonance imaging for differentiation of renal tumors.

OBJECTIVE: To investigate utility and limitations of 3-Tesla diffusion-weighted (DW) magnetic resonance imaging (MRI) for differentiation of benign versus malignant renal lesions and renal cell carcinoma (RCC) subtypes. MATERIALS AND METHODS: Sixty patients with 71 renal lesions underwent 3 Tesla DW-MRI of the kidney before diagnostic tissue confirmation. The images were retrospectively evaluated blinded to histology. Single-shot echo-planar imaging was used as the DW imaging technique. Apparent diffusion coefficient (ADC) values were measured and compared with histopathological characteristics. RESULTS: There were 54 malignant and 17 benign lesions, 46 lesions being small renal masses ≤ 4 cm. Papillary RCC lesions had lower ADC values (p=0.029) than other RCC subtypes (clear cell or chromophobe). Diagnostic accuracy of DW-MRI for differentiation of papillary from non-papillary RCC was 70.3% resulting in a sensitivity and specificity of 64.3% (95% CI, 35.1-87.2) and 77.1 (95% CI, 59.9-89.6%). Accuracy increased to 83.7% in small renal masses (≤ 4 cm diameter) and sensitivity and specificity were 75.0% and 88.5%, respectively. The ADC values did not differ significantly between benign and malignant renal lesions (p=0.45). CONCLUSIONS: DW-MRI seems to distinguish between papillary and other subtypes of RCCs especially in small renal masses but could not differentiate between benign and malignant renal lesions. Therefore, the use of DW-MRI for preoperative differentiation of renal lesions is limited.

Magnetic resonance imaging-guided prostate biopsy: institutional analysis and systematic review.

OBJECTIVES: To evaluate the detection rate of prostate cancer (PCa) after magnetic resonance-guided biopsy (MRGB); to monitor the patient cohort with negative MRGB results and to compare our own results with other reports in the current literature. MATERIALS AND METHODS: A group of 41 patients was included in this IRB-approved study and subjected to combined MRI and MRGB. MRGB was performed in a closed 1.5 T MR unit and the needle was inserted rectally. The follow-up period ranged between 12 and 62 months (mean 3.1 years). To compare the results with the literature, a systematic literature search was performed. Eighteen publications were evaluated. RESULTS: The cancer-suspicious regions were punctured successfully in all cases. PCa was detected in eleven patients (26.9 %) who were all clinically significant. MRGB showed a benign histology in the remaining 30 patients. In the follow-up (mean 3.1 years) of patients with benign histology, no new PCa was diagnosed. The missed cancer rate during follow-up was 0.0 % in our study. CONCLUSION: MRGB is effective for the detection of clinically significant cancer, and this is in accordance with the recent literature. In the follow-up of patients with benign histology, no new PCa was discovered. Although the probability of developing PCa after negative MRGB is very low, active surveillance is reasonable.

The use of mannitol in partial and live donor nephrectomy: an international survey.

PURPOSE: Animal studies have shown the potential benefits of mannitol as renoprotective during warm ischemia; it may have antioxidant and anti-inflammatory properties and is sometimes used during partial nephrectomy (PN) and live donor nephrectomy (LDN). Despite this, a prospective study on mannitol has never been performed. The aim of this study is to document patterns of mannitol use during PN and LDN. MATERIALS AND METHODS: A survey on the use of mannitol during PN and LDN was sent to 92 high surgical volume urological centers. Questions included use of mannitol, indications for use, physician responsible for administration, dosage, timing and other renoprotective measures. RESULTS: Mannitol was used in 78 and 64 % of centers performing PN and LDN, respectively. The indication for use was as antioxidant (21 %), as diuretic (5 %) and as a combination of the two (74 %). For PN, the most common dosages were 12.5 g (30 %) and 25 g (49 %). For LDN, the most common doses were 12.5 g (36.3 %) and 25 g (63.7 %). Overall, 83 % of centers utilized mannitol, and two (percent or centers??) utilized furosemide for renoprotection. CONCLUSIONS: A large majority of high-volume centers performing PN and LDN use mannitol for renoprotection. Since there are no data proving its value nor standardized indication and usage, this survey may provide information for a randomized prospective study.

[Energy ablative therapy of renal tumours]. / Energieablative Therapie von Nierentumoren.

Solid renal tumours with a diameter <4 cm may be effectively cured by partial nephrectomy but this is associated with a complication rate of 15-20%. In addition, these tumours are more frequently diagnosed in the elderly (<70 years) and 26% are aggressive G3 and potentially hazardous tumours. Since these tumours are frequently unifocal, spherical, peripherally located and easily accessible for minimally invasive approaches, energy ablative techniques are attractive less invasive therapeutic options. These tumours may be treated by freezing (cryoablation) or by heat (radiofrequency ablation, high intensified focused ultrasound). Cryoablation seems to be the most reliable technique with a 1.6% recurrence rate over 3 years follow-up but only 1.8% complications. Conversely skipping renders RFA unreliable in highly vascularised tumours >3 cm with 23% vital tumours to be found at histological work-up. Laparoscopic HIFU is still experimental. Percutaneous techniques are less effective as compared with laparoscopy with recurrence rates ranging between 13-21% (cryoablation) and 14-18% (RFA). In addition, oncological follow-up relies solely on radiological measurements, frequently without histological verification thus making percutaneous techniques unpredictable.

Morbidity of laparoscopic extraperitoneal versus transperitoneal radical prostatectomy verus open retropubic radical prostatectomy.

OBJECTIVE: Morbidity and postoperative pain after extraperitoneal (E-LRPE) and transperitoneal (T-LRPE) laparoscopic radical prostatectomy was compared to open extraperitoneal radical prostatectomy (O-RPE). MATERIAL AND METHODS: Between January 2002 and October 2003, we evaluated 41 E-LRPE, 39 T-LRPE and 41 O-RPE prospectively. All operations were performed as standard procedures by the same group of surgeons and perioperative results and complications were evaluated. Pain management was performed with tramadol 50-100 mg on demand, and no other form of anaesthesia was given. Postoperative pain was assessed daily in all patients quantifying analgesic requirement and evaluation of Visual Analogue Scale (VAS). All patients had at least a 12 month follow-up. RESULTS: Mean age, prostate volume, PSA and Gleason score were comparable between all three groups (p>0.05). Mean blood loss was lower with laparoscopy (189+/-140 and 290+/-254 ml), as compared to 385+/-410 ml for O-RPE (p=0.002). However, mean operating times were significantly longer in L-TRPE (279+/-70 min) as compared to E-LRPE (217+/-51 min) and O-RPE (195+/-72 min) (p<0.001), but E-LRPE and O-RPE showed no statistical difference (p=0.1143). Average VAS score on the 1st and 5th postoperative day for E-LRPE versus T-LRPE versus O-RPE was 4.9+/-1.0 versus 7.8+/-1.5 versus 5.8+/-1.9 and 1.6+/-0.9 versus 2.3+/-1.2 versus 2.3+/-0.9 respectively, which was significant lower (p=0.02) between E-LRPE versus T-LRPE (p<0.001) and O-RPE (p=0.008), but equal (p=0.655) between T-LRPE and O-RPE since postoperative day 3. Mean tramadol analgesic consumption within the first postoperative week was 290 versus 490 versus 300 mg respectively, which was statistical different between E-LRPE and T-LRPE (p<0.001), O-RPE and T-LRPE (p<0.001), but not between E-LRPE and O-RPE (p=0.550). Statistical analysis revealed a strong correlation of urinary leakage with increased postoperative pain (p=0.029) in all groups, especially for T-LRPE (p=0.007). Likewise, increased operating times (>240 min) were associated with increased post-operative pain (p=0.049). Full continence defined as no pads at one year was achieved in 36/41 (88%, E-LRPE) versus 33/39 (85%, T-LRPE) versus 33/41 (81%, O-RPE), respectively (p=0.2). CONCLUSION: E-LRPE resulted in a significant subjective (VAS Score, p<0.001) and objective (analgetic consumption, p<0.001) pain reduction compared to T-LRPE, but only in VAS Score compared to O-RPE (p=0.008). Analgetic consumption during first postoperative week was equal in E-LRPE (290 mg) and O-RPE (300 mg) (p=0.550). Shorter operating times, lower urinary leakage rates, lower stricture rates and lower blood loss in E-LRPE compared to T-LRPE are mainly explained due to the long learning curve in LRPE, which we did not overcome yet, and not due to the approach (extraperitoneal versus transperitoneal).

Modified laparoscopic nephroureterectomy for treatment of upper urinary tract transitional cell cancer is not associated with an increased risk of tumour recurrence.

INTRODUCTION: Laparoscopic nephroureterectomy reduces the morbidity of surgical management of urinary tract transitional cell carcinoma (TCC), but a potentially increased risk for local tumour spreading was reported. We evaluated results obtained from patients undergoing a modified laparoscopic approach and open procedures in this respect. PATIENTS AND METHODS: Between January 2000 and March 2002 we performed 19 modified laparoscopic nephroureterectomies (LNU) with open intact specimen retrieval in conjunction with open distal ureter and bladder cuff removal and 15 open standard nephroureterectomies (ONU). Staging lymphadenectomy was performed in 14/19 (73.7%) patients with LNU and in 6/15 (40.0%) with ONU. In all patients operating time, blood loss, complications, pain score (VAS) and data in respect to tumour recurrence were analysed. Mean follow-up was 22.1+/-9.2 (range 14-34) months for LNU and 23.1+/-8.8 (14-36) for ONU respectively. RESULTS: In LNU and ONU pathological features were 12 pT1 vs. 10 pT1, 2 pT2 vs. 2 pT2 and 5 pT3 vs. 3 pT3, respectively. All patients had TCC and were R0 at final histology. Four patients with LNU had lymph node involvement, one in ONU. LNU had decreased operating times (p=0.057), blood loss (p=0.018), complications (p=0.001) and VAS scores (p=0.001). One tumour recurrence occurred in LNU, associated with a pT3b pN2 G3 TCC at final histology. One patient with ONU had local tumour recurrence at the site of the bladder cuff. No port-site metastasis occurred during follow-up with LNU. CONCLUSION: Improved peri-operative results and same cancer control as compared to open surgery by this modified LNU was not associated with an increased risk for tumour recurrence, since strict "non-touch" preparation, avoiding of urine spillage and intact specimen retrieval prevents tumour seeding. However, results from long term studies are still warranted to clarify this issue.

Benefits of laparoscopic renal surgery are more pronounced in patients with a high body mass index.

PURPOSE: Aim of this prospective study was to determine whether patients with a higher body mass index (BMI) will benefit more from laparoscopic procedures in respect to postoperative morbidity and pain as compared to regular patients. PATIENTS AND METHODS: Between September 1999 and October 2001, we performed 36 laparoscopic radical nephrectomies and 18 nephron sparing partial nephrectomies for renal cell carcinoma and 6 nephrectomies for benign disease (group 1, n=60). In addition, we performed 24 open radical nephrectomies and 18 nephron spearing interventions for renal cell carcinoma (group 2, n=42). Mean age was 59+/-17.9 years and average BMI was 27.1+/-3.3 kg/m(2) in the entire group. All techniques were evaluated for intraoperative results and complications. Postoperative morbidity was assessed in all patients by quantifying pain medication and by daily evaluation of Visual Analogue Scale (VAS). RESULTS: Mean hospitalisation time in group 1 as compared to group 2 was 10.1 days versus 5.4 days, average operating time was 273 minutes versus 187 minutes, mean length of skin incision was 7.2 cm versus 30.8 cm. Overall analgesic consumption was lower in the laparoscopic group (190 mg versus 590 mg, p<0.001), in patients with a BMI >28 kg/m(2) the difference was even more pronounced (160 mg versus 210 mg, p=0.032). In group 1, patients with a BMI >28 kg/m(2) had significantly less pain on the first and fourth postoperative day in a linear regression analysis (VAS1=10.714-0.218 BMI; r=0.688 (p<0.001) and VAS4=3.98-0.09 BMI, r=0.519 (p<0.001), respectively). In group 1, 3/60 (5.0%) and in group 2, 5/42 (11.9%) complications occurred, no difference was found in respect to a high BMI (p=0.411). CONCLUSION: Patients with a higher BMI (cut-off >28 kg/m(2)) benefit more from laparoscopy than slim patients in respect to postoperative pain and morbidity but do not experience more complications. Consequently, reluctance to perform laparoscopic procedures in patients with a higher BMI is no longer justified.

Stone treatment and coagulopathy.

OBJECTIVE: The aim of this retrospective study was to evaluate treatment protocols and results of upper tract stone treatment in patients with clotting disorders. METHODS: In a 6-year period, 6,827 stone interventions (ESWL or endourologic procedures) were performed in 5,739 patients. Thirty-five (0.61%) patients suffered from a variety of systemic clotting disorders or were anti-coagulated. Clotting disorders were corrected by specific therapy prior to any intervention. A total of 76 interventions were performed consisting of ESWL, ureteroscopy (URS), percutaneous nephrolithotomy (PNL), ureteric stenting or percutaneous nephrostomy. RESULTS: All patients became stone-free within 3 months or had clinically insignificant residual fragments. Severe complications were observed in 10/76 (13.1%) interventions. ESWL was successful in 88.9% (16/18) of patients, but associated with a 33.3% (6/18) complication rate; 27.8% (5/18) of patients required auxiliary procedures. URS and PNL were successful in all cases and complications occurred in 0% (0/7) and 33% (1/3) of patients, respectively. Time to complete stone clearance after ESWL was 32.0+/-49.3 days compared with a mean of 19.4+/-28.6 days in a non-coagulopathy control group; no difference was observed for endourologic procedures. Average costs of treatment in patients undergoing ureteroscopy was higher in patients with coagulopathy (4,611 versus 2,342); however, the difference was less pronounced compared with ESWL (6,070 versus 1,731). CONCLUSION: Patients with coagulopathy have a higher rate of complications despite apparently normal clotting parameters during treatment and hospitalisation was prolonged. The efficacy of ESWL was lower in patients with coagulopathy and we currently favour endoscopic procedures for stone removal in this patient group.

Urolithiasis in allograft kidneys.

OBJECTIVES: Allograft stones are an uncommon clinical problem and management is mainly based on anecdotal experience, rather than analysis of larger series. METHODS: In an 8-year period, 19 patients were treated for 19 renal and 3 ureteral stones. In 9 patients, stones were transplanted and 10 formed de novo stones within a mean of 28 months (range 13 to 48) after transplantation. In 4 patients, stones were removed during transplantation. Seven patients were treated with extracorporeal shock wave lithotripsy (ESWL), 3 patients had stones removed percutaneously, 1 by antegrade ureteroscopy, and 1 at the time of ureteral reimplantation. Three patients passed stones spontaneously. RESULTS: In 3 of 4 patients with stones detected before transplantation, the procedure was completed successfully after endoscopic stone removal. Three of 5 patients with transplanted stones required emergency nephrostomy; 1 patient had permanent renal impairment. Three (42.9%) of 7 patients treated with ESWL needed transient nephrostomy; ultimately, all became stone free within a mean 15 days (range 10 to 40). Endoscopic stone removal always resulted in complete clearance without renal impairment. All patients were stone free during a follow-up of 29 months (range 13 to 48). CONCLUSIONS: Nine (47%) of 19 stones were actually transplanted. Therefore, intraoperative screening by ultrasonography with subsequent endoscopic removal is advisable. Small stones (4 mm or less) may be closely followed up, because they can pass spontaneously. ESWL is the treatment of choice for caliceal stones sized 5 to 15 mm. However, for stones greater than 15 mm or for ureteral stones, antegrade endoscopic procedures seem to be more favorable.

Local intratumoral tumor necrosis factor-alpha and systemic IFN-alpha 2b in patients with locally advanced prostate cancer.

To examine tolerability and activity of local, intratumoral tumor necrosis factor-alpha (TNF-alpha) and systemic interferon-alpha2b (IFN-alpha2b) in locally advanced, hormone-resistant prostate cancer (LA-HRPC), 10 patients with LA-HRPC (T4N x M0, n = 3, T4N x M1, n = 5; T4N1M1, n = 2) were treated with recombinant TNF-alpha injected locally into prostate tumor tissue at 4-week intervals (maximum of four cycles) combined with intermittent subcutaneous (s.c.) administration of 5 x 10(6) IU IFN-alpha2b. Twenty-nine TNF-alpha cycles were administered. Despite significant TNF-alpha leakage into the systemic circulation 2 h after intraprostatic application (from a mean of 9 to a mean of 416 pg/ml; p = 0.0034), TNF-alpha (and IFN-alpha2b) was well tolerated (WHO grade 1-2 toxicity), possibly because of its rapid neutralization by increasing soluble 55-kDa and 75-kDa TNF receptor levels in the serum (mean increase 268% and 91%, respectively) at the same time. TNF-alpha induced prostate tumor cell necrosis in all patients, leading to a significant reduction of prostate volume in 9 of 10 cases (mean 38%; p = 0.0025). The significant short-term increase of prostate-specific antigen (PSA) (mean 65%; p < 0.001), tissue polypeptide-specific antigen (TPS) (mean 85%; p = 0.001), and possibly interleukin-8 (IL-8) (mean 2687%; p < 0.009) serum levels within 4 h after TNF-alpha confirmed the cytotoxic effect in vivo. In the long term, serum PSA levels dropped by 18%-87%, reaching the nadir value 7 weeks after baseline. Objective responses of metastases were not seen. Intraprostatic administration of TNF-alpha is feasible at a tolerable toxicity in patients with LA-HRPC and, thus, may be a new treatment option for these patients.

[Submucous mucous membrane support in intrinsic sphincter insufficiency. A therapeutic approach in female stress incontinence]. / Submuköse Schleimhautunterfütterung bei intrinsischer Sphinkterinsuffizienz. Ein Therapieanatz bei weiblicher Stressinkontinenz.

Urethral bulking agents are an attractive alternative for treating patients with intrinsic sphincter deficiency (ISD), i.e., type III urinary stress incontinence. These endoscopic techniques are minimally invasive and can be used in high-risk patients. As bulking agents, Teflon, autologous fat, collagen, silicone particles, and detachable microballoons have been the object of considerable clinical research. Teflon forms granulomas in the surrounding tissue and tends to migrate and is now considered obsolete. More recently, human collagen, autologous cartilage, Bioglass, and hyaluronic acid with dextranomer and polycarbon particles have come under clinical investigation, but long-term results are still lacking. The optimal bulking agent should be nondegradable and biologically inert and should not migrate or change its bulking capability. To date, there is no consensus on the best agent fulfilling these requirements, but encapsulated substances appear most promising.

Use of peripheral neuromodulation of the S3 region for treatment of detrusor overactivity: a urodynamic-based study.

OBJECTIVES: To determine the efficacy of peripheral neuromodulation of the S3 region in patients with urgency-frequency syndrome due to an overactive bladder. METHODS: Fifteen patients (11 women and 4 men) with urgency-frequency syndrome, as documented by a voiding chart, were diagnosed with overactive bladder. Pelvic pain was assessed by a visual analogue scale (VAS). Full urodynamic workup was performed before and after 12 peripheral stimulations with a 9-V monopolar generator, the so-called Stoller Afferent Nerve Stimulator (SANS). Follow-up was for a mean (SD) of 10.9 (4 to 15) months. RESULTS: Reduction in pain was achieved in all patients, with a decrease in VAS from a mean (SD) of 7.6 (5 to 10) to 3.1 (1 to 7) (P = 0.00049). Seven patients (46.7%) had a complete response and were considered cured, 3 (20.0%) showed significant improvement, and 5 (33.3%) were classified as nonresponders. Urodynamic evidence of bladder instability, evident in all patients before treatment, was eliminated in 76.9% of patients. In all patients, mean (SD) total bladder capacity increased significantly from 197 (35 to 349) to 252 (78 to 384) mL (P = 0.00795), mean (SD) volume at first bladder sensation from 95 (16 to 174) to 133 (32 to 214) mL (P = 0.00166), and mean (SD) bladder volume at normal desire to void from 133 (27 to 217) to 188 (47 to 296) mL (P = 0.00232). In the responding group, the mean (SD) total numbers of voids was reduced from 16.1 (9 to 24) times during the day and 4.4 (2 to 6) times during the night to 8.3 (6 to 10) and 1.4 (1 to 2) times (P = 0.002539), respectively. No complications from treatment were observed. CONCLUSIONS: Peripheral neuromodulation of the S3 region can successfully treat patients with urgency-frequency syndrome due to an overactive bladder.

Serum dehydroepiandrosterone sulfate concentrations in men with erectile dysfunction.

OBJECTIVES: In 1994, the Massachusetts Male Aging Study presented the finding of an inverse correlation of the serum levels of dehydroepiandrosterone sulfate (DHEAS) and the incidence of erectile dysfunction (ED). Prompted by the positive results of a pilot study on the treatment of ED with dehydroepiandrosterone (DHEA), we performed a detailed investigation on the serum DHEAS levels in men with ED according to age category. METHODS: Inclusion criteria included a history of ED for more than 6 months, a body mass index less than 30, and a state of good general health. Serum DHEAS concentrations were determined in 309 patients with ED and 133 healthy volunteers. All participants were carefully screened to assess medical factors known or suspected to alter endocrine function. Questions 3 and 4 of the International Index of Erectile Function were used to evaluate erectile function. RESULTS: The mean serum levels of DHEAS in patients with ED were lower than in healthy volunteers until 60 years of age. The shape of the curve of the patients with ED indicated a quadratic decrease of DHEAS with age in contrast to a more linear decrease of DHEAS with age in the control group. CONCLUSIONS: Our results suggest that until the age of 60 years, the mean serum level of DHEAS is lower in patients with ED than in healthy volunteers.

Comparative study of two different TRUS-guided sextant biopsy techniques in detecting prostate cancer in one biopsy session.

OBJECTIVE: The aim of this study was to compare a transrectal ultrasound (TRUS)-guided sextant biopsy technique, which puts more emphasis on the apical region of the prostate where most prostate carcinomas (PCs) develop, with the standard sextant biopsy technique. METHODS: A total of 280 patients with suspected PC were included in this analysis. Twelve biopsy cores were obtained from all patients. Six biopsy cores were taken within a lateral parasagittal plane from each lobe at the apex, middle and basis, with an angle of approximately 45 degrees (technique A), and 6 further biopsy cores were taken from the left to the right lateral margin always penetrating the prostate in the apex with the same angle (socalled fan-shaped technique, technique B). Technique A predominantly samples in the sagittal and technique B samples more in the transversal plane with emphasis on the apical region where most PCs develop. The sensitivity in detecting PCs for both techniques was calculated and correlated to the serum prostate-specific antigen (PSA) levels. RESULTS: A total of 72 PCs (25.7%) were diagnosed. We subsequently performed subgroup analysis depending on the serum PSA levels: in patients with a PSA of 10 ng/ml (n = 45) technique A has a PC sensitivity of 93.3% (p = 0.083) and technique B 88.8% (p = 0.023) as compared to our reference standard. The number of positive core biopsies using technique A was superior in 14 cases as compared to 12 with technique B (p = 0.154). In 19 patients the number of positive biopsies was identical. CONCLUSION: Our data suggest that in patients with PSA of

Role of bacteria in the development of kidney stones.

Currently, only struvite stones are regarded as deriving from bacteria. Recent work has suggested that calcium-based stones might also have an infectious origin. Nanobacteria, small intracellular bacteria found in human kidney stones, are capable of forming a calcium phosphate shell, and thus could serve as crystallization centres for renal calculi formation. Until now, however, all trials performed to confirm the presence of nanobacteria in human calculi, serum or urine have failed. In a hyperoxaluric rat model, tissue-residing macrophages were able to remove interstitial crystals and thus may not be primarily engaged in defending against micro-organisms, if present.

Value of power Doppler sonography in the investigation of erectile dysfunction.

OBJECTIVES: The poor sensitivity of conventional color-coded Doppler sonography (CCD) for low-flow signals limits its use for investigating patients with erectile dysfunction. Power Doppler sonography (PD) has recently been described for enhanced visualization of the microcirculation. Aim of this study was to determine the value of PD to demonstrate penile vascular pathophysiology as compared with conventional techniques. METHODS: 33 consecutive men with erectile dysfunction were investigated using the standard workup with conventional CCD and cavernosography before and after prostaglandin E(1) intracavernosal injection. Patients were subdivided into an arteriogenic, a venogenic, or a psychogenic group according to findings in the standard diagnostic workup. PD was used in addition to the standard protocol to demonstrate microcirculation, arterial blood flow, and venous leakage. The accuracy of the diagnosis obtained by PD and response to intracavernosal injection was compared with the clinical outcome in these groups at 6 months. RESULTS: PD was found to be superior to CCD in visualizing cavernosal microcirculation. In addition, arterial flow at basal peak systolic velocity was demonstrated in all patients with PD, whereas a signal sufficient for evaluation was obtained with CCD in only 69.7% (23/ 33). No significant difference in the maximal peak systolic velocity was noted using either PD or CCD. The positive predictive value of PD for venous leakage was poor (60%) when compared with cavernosography. PD used in conjunction with the response to intracavernosal injection was found to reliably predict the clinical outcome in the arteriogenic (p = 0.0007), the venogenic (p = 0.005), and the psychogenic group (p = 0.0002). CONCLUSIONS: Our data indicate that PD improves the evaluation of penile microcirculation and arterial function, but fails to reliably demonstrate venous leakage alone. Nevertheless, in most patients cavernosography could have been avoided by the aid of PD, since the underlying pathology can be calculated at a high predictive value without the need of further invasive tests. Therefore, with the aid of PD, the morbidity for patients being investigated for erectile dysfunction can be significantly reduced.

Regulation of prostatic stromal cell growth and function by transforming growth factor beta (TGFbeta).

BACKGROUND: The majority of the overgrowth in benign prostatic hyperplasia (BPH) specimens is comprised of connective tissue. Factors that control stromal growth in the prostate are poorly understood; however, members of the transforming growth factor beta (TGFbeta) family may be of particular importance in the etiology of BPH. METHODS: Thirty-two low-passage stromal cultures were generated from human prostatectomy specimens. Their stromal origin was confirmed and expression of TGFbetas analyzed by duplex reverse transcription-polymerase chain reaction (RT-PCR). Challenge experiments were designed to study the effects of exogenous TGFbeta1 on stromal cell growth and synthesis of extracellular matrix components. RESULTS: The expression of TGFbetas 1, 2, and 3 was demonstrated in all 32 cell strains. The stromal origin of the cell lines was confirmed. Exogenous TGFbeta1 added to stromal cultures resulted in inhibition of cell growth and increased production of type I collagen. CONCLUSIONS: The prostatic stromal cell strains we have developed are a reliable mod- el for investigating prostatic connective tissue biology. The challenge experiments with TGFbeta1 provide further evidence for the involvement of TGFbetas in prostatic enlargement, as modulators of the extracellular matrix in the absence of growth stimulation.

Outcome analysis of minimally invasive treatments for benign prostatic hyperplasia.

The armamentarium of minimally invasive treatment modalities for patients with benign prostatic hyperplasia has increased steadily during the past decade. The energy sources used range from microwaves and radiofrequency waves to high-intensity focused ultrasound, with laser vaporization/coagulation/resection and electrosurgical techniques. The large amount of data available allow some conclusions to be drawn concerning the present role of the "gold standard" TURP among the minimally invasive procedures. Although the subjective response after TURP and other minimally invasive procedures is comparable, improvements of flow and urodynamic parameters usually are more pronounced after TURP. Failure rates requiring reintervention (usually TURP) are considerable. Minimally invasive procedures lead to a shift of morbidity from the intraoperative phase, which is reduced (risk of bleeding, TUR syndrome, transfusion) to the postoperative phase. This period is characterized by prolonged urinary retention (ILC, VLAP), significant dysuria (VLAP, TUVP), and nycturia. Recent advances in electrosurgical techniques, such as band TURP loops that facilitate coagulation due to the longer contact time between the electrode and the tissue, have the potential to convert TURP into a less invasive procedure. Finally, high-energy TUMT seems to offer a truly minimally invasive treatment combining efficacy and the need for topical anesthesia only. However, due to a lack of homogeneity of criteria for patient recruitment, parameters of evaluation, and adequate follow-up; accurate guidelines for appropriate patient management have not been established yet.