In vivo ureteroscopic intrarenal pressures and clinical outcomes: a multi-institutional analysis of 120 consecutive patients

OBJECTIVES

To evaluate the pressure range generated in the human renal collecting system during ureteroscopy (URS), in a large patient sample, and to investigate a relationship between intrarenal pressure (IRP) and outcome.

PATIENTS AND METHODS

A prospective multi-institutional study was conducted, with ethics board approval; February 2022-March 2023. Recruitment was of 120 consecutive consenting adult patients undergoing semi-rigid URS and/or flexible ureterorenoscopy (FURS) for urolithiasis or diagnostic purposes. Retrograde, fluoroscopy-guided insertion of a 0.036-cm (0.014″) pressure guidewire (COMET™ II, Boston Scientific, Marlborough, MA, USA) to the renal pelvis was performed. Baseline and continuous ureteroscopic IRP was recorded, alongside relevant operative variables. A 30-day follow-up was completed. Descriptive statistics were applied to IRP traces, with mean (sd) and maximum values and variance reported. Relationships between IRP and technical variables, and IRP and clinical outcome were interrogated using the chi-square test and independent samples t-test.

RESULTS

A total of 430 pressure traces were analysed from 120 patient episodes. The mean (sd) baseline IRP was 16.45 (5.99) mmHg and the intraoperative IRP varied by technique. The mean (sd) IRP during semi-rigid URS with gravity irrigation was 34.93 (11.66) mmHg. FURS resulted in variable IRP values: from a mean (sd) of 26.78 (5.84) mmHg (gravity irrigation; 12/14-F ureteric access sheath [UAS]) to 87.27 (66.85) mmHg (200 mmHg pressurised-bag irrigation; 11/13-F UAS). The highest single pressure peak was 334.2 mmHg, during retrograde pyelography. Six patients (5%) developed postoperative urosepsis; these patients had significantly higher IRPs during FURS (mean [sd] 81.7 [49.52] mmHg) than controls (38.53 [22.6] mmHg; P < 0.001).

CONCLUSIONS

A dynamic IRP profile is observed during human in vivo URS, with IRP frequently exceeding expected thresholds. A relationship appears to exist between elevated IRP and postoperative urosepsis.

Upper urinary tract pressures in endourology: a systematic review of range, variables and implications

OBJECTIVES

To systematically review the literature to ascertain the upper tract pressures generated during endourology, the relevant influencing variables and clinical implications.

MATERIALS AND METHODS

A systematic review of the MEDLINE, Scopus and Cochrane databases was performed by two authors independently (S.C., N.D.). Studies reporting ureteric or intrarenal pressures (IRP) during semi-rigid ureteroscopy (URS)/flexible ureterorenoscopy (fURS)/percutaneous nephrolithotomy (PCNL)/miniaturized PCNL (mPCNL) in the period 1950-2021 were identified. Both in vitro and in vivo studies were considered for inclusion. Findings were independently screened for eligibility based on content, with disagreements resolved by author consensus. Data were assessed for bias and compiled based on predefined variables.

RESULTS

Fifty-two studies met the inclusion criteria. Mean IRP appeared to frequently exceed a previously proposed threshold of 40 cmH₂ O. Semi-rigid URS with low-pressure irrigation (gravity <1 m) resulted in a wide mean IRP range (lowest reported 6.9 cmH₂ O, highest mean 149.5 ± 6.2 cmH₂ O; animal models). The lowest mean observed with fURS without a ureteric access sheath (UAS) was 47.6 ± 4.1 cmH₂ O, with the maximum peak IRP being 557.4 cmH₂ O (in vivo human data). UAS placement significantly reduced IRP during fURS, but did not guarantee pressure control with hand-operated pump/syringe irrigation. Miniaturization of PCNL sheaths was associated with increased IRP; however, a wide mean human IRP range has been recorded with both mPCNL (lowest -6.8 ± 2.2 cmH₂ O [suction sheath]; highest 41.2 ± 5.3 cmH₂ O) and standard PCNL (lowest 6.5 cmH₂ O; highest 41.2 cmH₂ O). Use of continuous suction in mPCNL results in greater control of mean IRP, although short pressure peaks >40 cmH₂ O are not entirely prevented. Definitive conclusions are limited by heterogeneity in study design and results. Postoperative pain and pyrexia may be correlated with increased IRP, however, few in vivo studies correlate clinical outcome with measured IRP.

CONCLUSIONS

Intrarenal pressure generated during upper tract endoscopy often exceeds 40 cmH₂ O. IRP is multifactorial in origin, with contributory variables discussed. Larger prospective human in vivo studies are required to further our understanding of IRP thresholds and clinical sequelae.

Gleason grade accuracy of transperineal and transrectal prostate biopsies in MRI-naïve patients

PURPOSE

Accurate assessment of Gleason grade is essential to guiding prostate cancer management. Not all healthcare systems have universal access to prostate MRI. We investigated whether transperineal (TP) prostate biopsies provide more accurate Gleason grading than transrectal (TR) biopsies in MRI-naïve patients.

METHODS

Consecutive patients undergoing TP and TR systematic prostate needle biopsies from 2011 to 2018 were analysed. Patients who underwent radical prostatectomy (RP) within 180 days of biopsies were included. Patients undergoing MRI prior to biopsies were excluded. Pathological concordance, incidence of Gleason upgrading, and correlation coefficients among biopsies and RP Gleason grade were compared. A sub-analysis for concordance in anterior prostate tumours was conducted.

RESULTS

262 patients were included (112 TP; 150 TR), the median age was 63 years, and median time from biopsy to RP was 68 days. Concordance with RP histology for TP was 65% compared to 49% for TR (p = 0.011). Biopsy technique predicted RP concordance independent of the number of cores. Gleason upgrading occurred following 24% of TP versus 33% of TR biopsies. In anterior and apical tumours, upgrading occurred in 19% of TP biopsies and 38% of TR biopsies (p = 0.027).

CONCLUSION

This study suggests TP approach to prostate biopsies result in improved histological grade accuracy in men whom MRI is not available, even after controlling for number of cores. TP approach also resulted in less upgrading for lesions in the anterior and apical prostate compared to TR.

Which has more complications?—Shockwave lithotripsy versus endoscopic treatment of renal calculi with 1‐year follow‐up in an Australian population

Introduction and objectives

Renal calculi are a common medical problem with incidence rates calculated to be approximately 6%‐9% in men & 3%‐4% in women worldwide. Incidence appears to be increasing. This study compares emergency presentations and unplanned readmissions between extracorporeal shock wave lithotripsy (SWL) and pyeloscopic stone treatment in the population of Victoria, Australia after 1‐year follow‐up.

Methods

This is a population study comparing all patients with renal calculi electively treated with SWL to those initially treated with flexible ureteroscopy (URS) in Victoria, Australia. We used data linkage across the state of Victoria to follow patients treated with either modality in a 12 months period (with no urological surgery in the prior 12 months). Each patient's emergency presentations and subsequent re‐admissions were followed up for 1 year after their index treatment to assess for stone complications. We assessed for selection bias between the two patient groups by comparing age, gender, insurance status, geographical location, and comorbidity scores.

Results

We report stone‐related complications for 739 flexible URS and 1317 SWL procedures undertaken across public and private hospitals in Victoria over 12 months. Unplanned emergency presentations within 60‐days of surgery were (22/739) 2.98% for flexible URS patients and (83/1317) 6.30% for SWL patients (P = .001); however, at 12 months, this became 16.23% (120/739) for flexible URS patients and 12.83% (169/1317) for SWL patients (P = .034). Flexible URS patients were more likely than SWL patients to be admitted with 71.76% of flexible URS versus 53.97% of SWL patients requiring an admission at any given emergency presentation (P ≤ .001) within 12 months. On multivariate analysis, both flexible URS ([OR] 1.67, CI 1.23‐2.26, P = .001) and being a public patient ([OR] 3.06, CI 2.24‐4.18, P < .001) significantly increased the likelihood that patients required an unplanned re‐admission within 12 months.

Conclusions

There is work needed to reduce emergency presentations and unplanned re‐admissions after both SWL and flexible URS. At 12‐months follow‐up, unplanned emergency visits and re‐admission rates were significantly more after flexible URS. Symptoms at emergency presentation indicate that better education regarding stent management is needed, especially in the public health care system.

What is the best way to manage ureteric calculi in the time of COVID‐19? A comparison of extracorporeal shockwave lithotripsy (SWL) and ureteroscopy (URS) in an Australian health‐care setting

Objectives

To determine the best way to intervene for ureteric stones which still require treatment during the COVID‐19 pandemic, with respect to infection control. In this setting, in which resources are constrained, extracorporeal shockwave lithotripsy (SWL) has prima facie advantages over ureteroscopy (URS). It is also necessary to also consider posttreatment resource consumption in regards to complications and repeat procedures.

Subjects and methods

The ideal ureteric stone treatment during a pandemic such as COVID‐19 would involve minimum resource consumption and a minimum number of patient attendances. We compared all patients initially treated with SWL to those initially treated with URS for acute ureteral colic within the state of Victoria, Australia in 2017.

Results

A total of 2724 ureteric stones were analyzed, a cumulative “3‐month exposure and burden on the healthcare system” was calculated for each patient by their initial procedure type. The readmission rate for URS was significantly higher than for SWL, 0.92 readmissions/patient for URS versus 0.54 readmissions/patient for SWL (P < .001). The cumulative hospital stay per patient for these two procedures was 2.35 days for SWL versus 3.21 days for URS (P < .001). The number of procedures per patient was 1.52 for SWL versus 1.89 for URS (P = .0213).

Conclusions

Patients with ureteric stones treated initially by SWL have shorter length of stay with fewer overall attendances and procedures at 3 months than those treated with URS. During a pandemic such as COVID‐19, SWL may have benefits in preserving hospital resources and limiting opportunity for virus transmission, compared to URS.

Pressurized-Bag Irrigation Versus Hand-Operated Irrigation Pumps During Ureteroscopic Laser Lithotripsy: Comparison of Infectious Complications

Introduction and Objectives: A variety of irrigation systems are available during ureteroscopy. We sought to compare gravity-driven pressure bags with hand-operated irrigation pumps in terms of postoperative complications after ureteroscopy with lithotripsy. Methods: A retrospective analysis of 234 patients undergoing flexible ureteropyeloscopy with laser lithotripsy by 24 supervised trainees over 4 years at a single teaching institution. Patients were divided into those who had procedures performed by using gravity-driven pressure bags fixed at 60 to 204 cm H₂O, vs those who had procedures performed by using a hand-operated irrigation pump capable of delivering 1 to 10 mL per flush. Variables including surgical duration, hypotension, fever, sepsis, and hematuria were extracted from the charts, along with the surgical techniques utilized. Statistical analyses included chi-squared tests and Student's t-tests. Results: There were no differences in gender, age, indication, or stone size in the two groups. Postoperative systemic inflammatory response syndrome was significantly greater in the hand-assisted n = 11/144 (7.6%) compared with the fixed irrigation group n = 1/90 (1.1%); p = 0.032. Emergency room presentations were greater in the hand irrigation group, n = 46/144 (32%) vs n = 12/90 (13%) in the pressure-bag irrigation, p = 0.002. Postoperative fever was also greater in the hand pump irrigation cohort compared with the continuous pressure cohort (13/144 [9%] vs 1/90 [1%], p = 0.011). No statistical difference was found between the two groups with respect to stone clearance and subsequent procedures required (p = 0.123). Conclusions: This analysis suggests that using continuous flow irrigation at a fixed maximum pressure of 150 mmHg (204 cm H₂O) or less may result in decreased pain, infection, and sepsis compared with handheld pressure irrigation.

Stone clearance times with mini-percutaneous nephrolithotomy: Comparison of a 1.5 mm ballistic/ultrasonic mini-probe vs. laser

INTRODUCTION

A limitation of mini-percutaneous nephrolithotomy (mPCNL) is the narrow working channel of mini-nephroscopes, typically restricting instrumentation to 5 French (F) or smaller. We evaluated the efficacy of the 1.5 mm Swiss LithoClast ^® Trilogy (Trilogy) rigid probe and compared the results to consecutive cases performed with a 30 W Holmium:YAG (Ho:YAG) laser.

METHODS

A retrospective review of 30 consecutive mPCNL cases using the Trilogy and 30 W Holmium laser was performed. A 12 F MIPS nephroscope with a 16.5 F access sheath and 6.7 F working channel was used for all mPCNL cases. The Trilogy was used with a disposable 1.5 mm × 440 mm probe with dual ultrasonic and ballistic energy. The Ho:YAG laser was used with a 550 micron fibre and a maximum of 30 W. Stone clearance time (SCT) was defined by the total time interval between activation of the lithotripter until insertion of the nephrostomy tube and measured in mm²/minutes. SCT included time for fragment retrieval, equipment adjustments, and rigid and flexible nephroscopy during and after lithotripsy.

RESULTS

Eleven cases using a 1.5 mm Trilogy probe and 16 cases using a Ho:YAG laser met final inclusion criteria. Three cases using the Trilogy were excluded from final analysis due to conversion to alternative energy sources - two of those were upsized to standard PCNL and one was converted to laser. Mean stone diameter and density in the final Trilogy cohort was 26.7 mm and 1193 Hounsfield units (HU). Mean diameter and density in the laser cohort was 25.2 mm and 1049 HU. The mean stone area clearance time for Trilogy was 4.7±1.8 mm²/minute vs. 3.4±0.7 mm²/minute with Ho:YAG laser (p=0.21). For hard stones, defined as density >1000 HU, the Trilogy averaged 3.7±1.6 mm²/minutes, while the laser averaged 3.1±1.3 mm²/minutes (p=0.786). For soft stones, defined as <1000 HU, the Trilogy averaged 8.9±1.0 mm²/minutes compared to the Ho:YAG, which averaged 3.6±1.8mm²/minutes (p=0.019). No device-related complications occurred in either cohort.

CONCLUSIONS

The 1.5 mm mPCNL Trilogy probe was comparable to 30 W Ho:YAG laser for clearing hard stones. The Trilogy performed better than laser on soft stones with a HU density <1000 HU.

Medical therapy versus transurethral resection of the prostate (TURP) for the treatment of symptomatic benign prostatic enlargement (BPE): a cost minimisation analysis

PURPOSE

A cost minimisation analysis compares the costs of different interventions' to ascertain the least expensive over time. We compared different prostate targeted drug treatments with TURP to identify the optimal cost saving duration of a medical therapy for symptomatic benign prostatic enlargement (BPE).

METHODS

The Evolution registry is a prospective, multicentre registry, conducted by the European Association of Urology Research Foundation (EAUrf) for 24 months in 5 European countries. Evolution was designed to register the management of symptomatic BPE in clinical practice settings in 5 European countries. Direct cost evaluation associated with prostate targeted medical therapies and TURP was also recorded and analysed.

RESULTS

In total, 1838 men were enrolled with 1246 evaluable at 24 months. Medical therapies were more cost saving than TURP for treatment durations ranging from 2.9 to 70.4 years. Cost saving depended on both medication class and individual country assessed. Daily tamsulosin monotherapy was more cost saving than TURP for ≤ 13.9 years in Germany compared to ≤ 32.7 years in Italy. Daily finasteride monotherapy was more cost saving for ≤ 5.9 years in France compared to ≤ 36.9 years in Spain. Combination therapy was more cost saving for ≤ 5.9 years for Italian patients versus ≤ 13.8 years in Germany.

CONCLUSIONS

BPE medical management was more cost saving than TURP for different specific treatment durations. Information from this study will allow clinicians to convey medical and surgical costs over time, to both patients and payors alike, when considering BPE treatment.

The Role of Stem Cells for Reconstructing the Lower Urinary Tracts

BACKGROUND

The urinary bladder and urethra comprise the lower urinary tracts. Pathological conditions that affect both structures necessitate reconstructive urological intervention with autologous tissue sources that cause neuromechanical and metabolic complications. Stem-cell therapies may offer an attractive alternative as they can replicate important host derived cellular functions such as mitosis, proliferation, differentiation and apoptosis.

OBJECTIVE

To provide an overview on the application of stem cell therapies for regenerating the lower urinary tracts and to discuss factors that need to be addressed before stem-cells can be reliably introduced into clinical urological practice.

RESULTS

Advantages of stem cells in reconstructive urology are their ability to self-renew and their durability. Mesenchymal stem cells (MSCs), embryonic stem cells (ESCs) and adult stem cells (ASCs) demonstrate excellent urological regenerative properties. Repairing defective lower urinary tract structures with various stem-cell derived therapies has been widely reported with encouraging results in vitro and in pre-clinical in vivo trials. Ethical considerations, cost, regulation, manufacturing and reimbursement need to be fully transparent before stem-cells are routinely applied to urological patients. International collaboration with consensus guidelines should be considered to facilitate standards that allow safe use of stem-cell therapies in urology.

CONCLUSION

Stem cells therapies in urology are developing rapidly with many important achievements to date. Despite promising in vitro and pre-clinical data; implementation of stem cells into daily urological practice is not imminent. Further investigation is required to determine whether stem-cells will provide better clinical outcomes than current urological tissue replacement strategies.

Fragmentation of transrectal ultrasound-guided biopsy cores is influenced by the method of specimen retrieval

OBJECTIVE

To determine whether the method of specimen preparation after transrectal ultrasound-guided biopsy of the prostate affected core fragmentation, and secondly to determine whether such fragmentation was influenced by the presence of malignancy in the biopsy specimen.

METHODS

A prospective randomized study comparing 2 different mechanisms of specimen preparation, wash vs swipe of biopsy cores, with blinded assessment by a specific uropathologist was undertaken.

RESULTS

For those cores in which prostate cancer was present, the wash method of specimen preparation resulted in fewer and longer core fragments (P = .005). Those patients in whom cancer was present on biopsy also had a greater degree of biopsy core fragmentation in those cores in which only benign tissue was identified (P = .017). Gleason score did not appear to influence the extent of fragmentation.

CONCLUSION

The method of specimen preparation at prostate biopsy influences the degree of fragmentation seen at histologic evaluation. This has the potential to affect the interpretation of biopsy results, including suitability of patients for inclusion in active surveillance protocols. Core fragmentation might be minimized by modification of technique.

Integration of laparoscopic partial nephrectomy into an Australian public hospital: three-year follow-up of our initial 50 cases

OBJECTIVE

To examine the early outcomes and complications of integrating laparoscopic partial nephrectomy (LPN) into a public teaching hospital in Australia.

PATIENTS AND METHODS

An outcomes review from prospectively collected data on our initial 50 cases of LPN. The median follow-up was 36 months with a minimum follow-up of 2 years and a maximum of 5 years.

RESULTS

The mean patient age was 60 years, mean tumour size was 2.9 cm, and mean baseline creatinine concentration was 79 µmol/L. One patient had a solitary kidney, and one patient had bilateral tumours. The mean operative duration was 168 min, with a mean warm ischaemia time of 25 min. The median blood loss was 100 mL and the median (range) hospital stay was 4 (2-12) days. The complication rate was 6%, including two instances of secondary haemorrhage, and one port-site hernia. No patient required conversion to radical nephrectomy or experienced clinically significant deterioration in their renal function. There have been no local or systemic recurrences to date, with a maximum follow-up of 5 years.

CONCLUSIONS

LPN can be successfully integrated into the Australian public health care sector as standard of care for stage 1 renal masses requiring treatment. Due to the inherent risk of bleeding early in the learning curve, cases should be performed in the setting of adequate surgical and interventional radiographic support.

Nuclear fusion-independent smooth muscle differentiation of human adipose-derived stem cells induced by a smooth muscle environment

Human adipose-derived stem cells hASC have been isolated and were shown to have multilineage differentiation capacity. Although both plasticity and cell fusion have been suggested as mechanisms for cell differentiation in vivo, the effect of the local in vivo environment on the differentiation of adipose-derived stem cells has not been evaluated. We previously reported the in vitro capacity of smooth muscle differentiation of these cells. In this study, we evaluate the effect of an in vivo smooth muscle environment in the differentiation of hASC. We studied this by two experimental designs: (a) in vivo evaluation of smooth muscle differentiation of hASC injected into a smooth muscle environment and (b) in vitro evaluation of smooth muscle differentiation capacity of hASC exposed to bladder smooth muscle cells. Our results indicate a time-dependent differentiation of hASC into mature smooth muscle cells when these cells are injected into the smooth musculature of the urinary bladder. Similar findings were seen when the cells were cocultured in vitro with primary bladder smooth muscle cells. Chromosomal analysis demonstrated that microenvironment cues rather than nuclear fusion are responsible for this differentiation. We conclude that cell plasticity is present in hASCs, and their differentiation is accomplished in the absence of nuclear fusion.

Urinary bladder smooth muscle engineered from adipose stem cells and a three dimensional synthetic composite

Human adipose stem cells were cultured in smooth muscle inductive media and seeded into synthetic bladder composites to tissue engineer bladder smooth muscle. 85:15 Poly-lactic-glycolic acid bladder dome composites were cast using an electropulled microfiber luminal surface combined with an outer porous sponge. Cell-seeded bladders expressed smooth muscle actin, myosin heavy chain, calponinin, and caldesmon via RT-PCR and immunoflourescence. Nude rats (n=45) underwent removal of half their bladder and repair using: (i) augmentation with the adipose stem cell-seeded composites, (ii) augmentation with a matched acellular composite, or (iii) suture closure. Animals were followed for 12 weeks post-implantation and bladders were explanted serially. Results showed that bladder capacity and compliance were maintained in the cell-seeded group throughout the 12 weeks, but deteriorated in the acellular scaffold group sequentially with time. Control animals repaired with sutures regained their baseline bladder capacities by week 12, demonstrating a long-term limitation of this model. Histological analysis of explanted materials demonstrated viable adipose stem cells and increasing smooth muscle mass in the cell-seeded scaffolds with time. Tissue bath stimulation demonstrated smooth muscle contraction of the seeded implants but not the acellular implants after 12 weeks in vivo. Our study demonstrates the feasibility and short term physical properties of bladder tissue engineered from adipose stem cells.

Familial transmission of genitovaginal prolapse

Some females with little to no risk factors develop prolapse, while other females with multiple risk factors do not. It appears that some women may have a predisposition for prolapse in the setting of equivalent risk factors. We identified 10 patients younger than 55 years old with a family history of prolapse. Their average age was 37 years (range 27-51), the mean number of deliveries was 1.8, and their mean birth weight was 8 lbs. Genetic analysis of the inheritance pattern within these families demonstrated that pelvic organ prolapse segregated in a dominant fashion with incomplete penetrance in these families. Both maternal and paternal transmissions were observed. The relative risk to siblings of affected patients was five times that of the risk for the general population. Further investigation of these families may identify a genetic defect responsible for prolapse.

Conservative management options for peyronie’s disease

Peyronie's disease is an acquired condition that presents clinically with a palpable induration, a distinct plaque, or a curvature of the erect penis. At times, the erections are painful. Erectile dysfunction (ED) often is associated with Peyronie's disease. The current era of phosphodiesterase therapy for the treatment of ED seems to have increased the number of patients presenting for treatment of Peyronie's disease. During the past decade, significant advances have been made in understanding the pathophysiology of the disease, resulting in numerous nonsurgical therapies proposed for the treatment of Peyronie's disease. These medical treatments can be administered systemically, locally, or intralesionally. Unfortunately, there are few randomized, placebo-controlled trials to evaluate most of these proposed therapies. In evaluating therapies for Peyronie's disease, it must be remembered that the natural disease history includes spontaneous resolution of pain and even a small improvement in penile curvature in some men. This article reviews the natural history, scientific understanding, and nonsurgical treatment options for the mild to moderate Peyronie's deformities. Surgical therapy remains the mainstay of treatment for severe and refractory cases of Peyronie's disease that result in a physical or psychologic dysfunction.

Processed lipoaspirate cells for tissue engineering of the lower urinary tract: implications for the treatment of stress urinary incontinence and bladder reconstruction

PURPOSE

We performed a pilot study to investigate the ability of human adipose derived, multipotent stem cells to be delivered to and survive within bladder and urethral smooth muscle.

MATERIALS AND METHODS

Lipoaspirate was acquired from female patients undergoing liposuction. The lipoaspirate was processed to yield a pluripotent population of processed lipoaspirate (PLA) cells. For tissue delivery PLA cells were fluorescent labeled and suspended in Hanks' balanced salt solution (Sigma Chemical Co., St. Louis, Missouri). To assess PLA viability in multiple animal models 8 Rnu athymic rats (Charles River, Wilmington, Massachusetts) and 6 SCID mice (Taconic Farms, Oxnard, California) underwent laparotomy and injection of PLA cells into the bladder and urethra. An additional 8 rats underwent sham injection of Hanks' balanced salt solution alone. Experimental and control animals were sacrificed 2, 4, 8 and 12 weeks after injection, and the bladders and urethras were analyzed.

RESULTS

Self-regenerating, pluripotent PLA cells were easily isolated from human adipose tissue. Evaluation 2, 4, 8 and 12 weeks after injection demonstrated PLA cell viability and incorporation into the recipient smooth muscle. Eight weeks following injection PLA cells demonstrated in vivo expression of alpha-smooth muscle actin, an early marker of smooth muscle differentiation.

CONCLUSIONS

PLA cells are an easily accessible source of pluripotent cells, making them ideal for tissue regeneration. PLA cells remain viable up to 12 weeks in the lower urinary tract. Human PLA cells injected into the urinary tract show morphological and phenotypic evidence of smooth muscle incorporation and differentiation with time. PLA cells may provide a feasible and cost-effective cell source for urinary tract reconstruction.

New objective measures to quantify stress urinary incontinence in a novel durable animal model of intrinsic sphincter deficiency

Existing animal models of stress urinary incontinence (SUI) are limited because of the low rate of incontinence seen in the animals and to their relatively low durability. In addition, most methods described to measure incontinence are operator-dependent. The aim of this study was to develop a new durable animal model of SUI and establish objective measures to quantify SUI. We subjected female rats to transabdominal urethrolysis. At baseline and at 1, 4, 8, 12, and 24 wk after intervention, animals underwent cystometry and evaluation with abdominal leak point pressure (ALPP). Urethral resistance was evaluated by retrograde urethral perfusion pressure (RUPP). Tissues were obtained for histology and immunohistochemistry. Normal female rats had an average ALPP of 19.4 cmH2O and RUPP of 22.6 cmH2O at baseline. More than 93% of the animals had significantly decreased ALPP and RUPP after the procedure. The mean ALPP and RUPP decreased to 9.8 cmH2O and 11.2 cmH2O, respectively, by 1 wk after urethrolysis. These changes were maintained for up to 24 wk. Changes seen in urethral resistance and ALPP appear to be mediated by apoptosis, decreased neuronal mass, and smooth muscle atrophy. These results indicate that transabdominal urethrolysis is a reliable method of achieving durable decreased urethral resistance in a SUI model. RUPP and ALPP are objective and reproducible methods of assessing urethral resistance. Changes in continence and urethral resistance appear to be mediated by denervation and smooth muscle atrophy, which are seen in both elderly incontinent patients and in patients with intrinsic sphincter dysfunction.

Current treatment options for penile fractures

The diagnosis of "penile fracture" describes the traumatic rupture of the tunica albuginea of an erect penis. Penile fractures typically occur when the engorged penile corpora are forced to buckle and literally "pop" under the pressure of a blunt sexual trauma. Patients typically describe immediate detumescence, severe pain, and swelling as a result of the injury. Prompt surgical exploration and corporal repair is the most efficacious therapy. Although a majority of cases can be diagnosed from the history and physical examination alone, radiographic studies, including retrograde urethrography and corporal cavernosography can aid in the diagnosis of unusual cases.

Pathological parameters of radical prostatectomy for clinical stages T1c versus T2 prostate adenocarcinoma: decreased pathological stage and increased detection of transition zone tumors

PURPOSE

Studies of radical prostatectomy specimens have suggested that the majority of prostate specific antigen detected (clinical stage T1c) tumors are clinically significant. We compared tumor location and pathological parameters in the radical prostatectomy specimens of stages T1c versus T2 cases in a 3-year period. The percent of stage T1c disease represented a stable majority of patients undergoing treatment for clinically localized prostate cancer.

MATERIALS AND METHODS

From January 1, 1998 to December 31, 2000, 417 radical prostatectomies were performed at Vanderbilt University, including 246 for stage T1c and 108 for stage T2 disease. A total of 37 patients were excluded from study because of neoadjuvant antiandrogen treatment. Pathological parameters, including tumor location in the transition and/or peripheral zone, tumor Gleason grade, tumor stage, total tumor volume and surgical margins were compared in stages T1c and T2 cases, and in transition versus peripheral zone stage T1c tumors in completely embedded whole mount specimens.

RESULTS

In contrast to stage T2 lesions, stage T1c tumors were of significantly lower Gleason score with a higher percent of Gleason score 5 and lower percent of Gleason score 6, 7 and 8 or greater. They also had a significantly smaller volume and lower pathological stage. Of stage T1c tumors 77% were organ confined versus 62% of stage T2 tumors. There was no statistically significant increase in clinically insignificant neoplasms in stages T1c versus T2 cases (13% versus 7%) when using a volume criterion of less than 0.2 cc but a statistically significant increase in clinically insignificant disease was observed using a volume criterion of less than 0.5 cc (22% versus 9%). Whereas none of the T2 tumors were located in the transition zone and 17% were located in the transition and peripheral zones, 14% of stage T1c lesions were exclusively in the transition zone, with another 17% in the transition and peripheral zones. Compared with peripheral zone tumors transition zone stage T1c tumors had a lower Gleason score with an increase in Gleason score 5 and lower percent of Gleason score 6, 7 and 8 or greater. Although transition zone stage T1c lesions were significantly larger than peripheral zone stage T1c lesions, they had a lower pathological stage with 94% versus 72% organ confined.

CONCLUSIONS

Prostate specific antigen detected stage T1c tumors had a lower grade, stage and volume than stage T2 tumors during the same period. Lower tumor grade in stage T1c cases is due at least in part to the increased detection of Gleason pattern 2 containing transition zone tumors. Despite the larger size, T1c transition zone tumors appear to be more favorable with higher rates of organ confined and lower grade tumors. If such transition zone tumors prove to be biologically distinct, improved strategies to identify these lesions preoperatively may result in more conservative treatment recommendations.

Improved risk stratification for biochemical recurrence after radical prostatectomy using a novel risk group system based on prostate specific antigen density and biopsy Gleason score

PURPOSE

Previous studies have suggested that prostate specific antigen (PSA) density is a significant independent predictor of biochemical failure after primary therapy. We determined whether pathological PSA density using surgical weight of the radical prostatectomy specimen was an independent predictor of adverse pathological features or biochemical recurrence after radical prostatectomy. We also examined whether combining pathological PSA density with biopsy Gleason score improved risk stratification compared with serum PSA and biopsy Gleason score for predicting PSA recurrence after prostatectomy.

MATERIALS AND METHODS

Multivariate analysis was used to determine whether pathological PSA density was an independent predictor of adverse pathology or PSA recurrence after radical prostatectomy in 325 patients treated at a Veterans Affairs medical center. Cutoff points of pathological PSA density were generated to identify patients at various risks for biochemical recurrence. These cutoffs were combined with biopsy Gleason cutoff points 2 to 6, 7 and 8 to 10 to generate a risk stratification system that was compared with a previous risk stratification system using PSA and biopsy Gleason score cutoff points. The validity of the risk stratification system using pathological PSA density and biopsy Gleason score was evaluated in another cohort of 490 patients treated with radical prostatectomy at a tertiary care medical center.

RESULTS

Pathological PSA density was an independent predictor of positive surgical margins (p <0.001), nonorgan confined disease (p <0.001), seminal vesicle invasion (p = 0.003) and biochemical recurrence after radical prostatectomy (p <0.001). The cutoff points for pathological PSA density of less than 0.3, 0.3 to 0.7 and greater than 0.7 ng./ml./gm. separated patients into 3 distinct groups at increasing risk for biochemical failure after radical prostatectomy (p <0.001). Pathological PSA density cutoffs combined with biopsy Gleason score cutoffs 2 to 6, 7 and 8 to 10 provided better risk stratification for biochemical failure than cutoffs based on a combination of PSA and biopsy Gleason score in patients treated at the Veterans Affairs (hazards ratio 3.04, confidence interval 2.25 to 4.11, p <0.001) and tertiary care (hazards ratio 2.38, confidence interval 1.78 to 3.18, p <0.001) medical centers.

CONCLUSIONS

Pathological PSA density was a strong predictor of advanced pathology and biochemical failure after radical prostatectomy. Pathological PSA density combined with biopsy Gleason score defined a novel risk group system that improved risk stratification compared with a combination of PSA and biopsy Gleason score. These results were validated in another cohort of patients treated with radical prostatectomy at a tertiary care medical center. Further studies are required using PSA density values calculated from preoperative transrectal ultrasound measurements to determine whether a combination of PSA density and biopsy Gleason score provides significant pretreatment risk stratification.

Percent of cancer in the biopsy set predicts pathological findings after prostatectomy

PURPOSE

The ability to use pretreatment variables to identify patients with organ confined prostate cancer continues to challenge physicians. We examined information available preoperatively, including prostate needle biopsy, clinical stage and preoperative prostate specific antigen (PSA), and evaluated these data based on pathological variables after radical retropubic prostatectomy.

MATERIALS AND METHODS

We reviewed results in 135 consecutive patients who underwent radical retropubic prostatectomy at a single institution. Needle biopsy information, such as the number of cores, percent of tumor per biopsy set, laterality of positive cores and Gleason sum, were compared with pathological data on the radical retropubic prostatectomy specimen, including pathological stage, Gleason sum and tumor volume. Clinical data, including biopsy information and pathological findings, were compared using univariate and multivariate models.

RESULTS

Overall total PSA, percent of tumor in the biopsy and bilateral positive cores directly correlated with tumor volume (p <0.01). Also, increasing PSA, increasing percent of tumor in the biopsy and bilateral positive cores were associated with increased risks of extracapsular extension (p <0.01).

CONCLUSIONS

From the information readily available from prostate needle biopsy these results suggest that percent of tumor in the biopsy is a useful predictor of pathological stage and tumor volume. Furthermore, including percent of tumor in the biopsy set and bilateral disease with traditional variables such as serum PSA and clinical stage may improve pretreatment tumor staging. This finding adds additional credence to the inclusion of percent of tumor in the biopsy set in models for the preoperative prediction of pathological stage and should be factored into discussions with patients on treatment options.

Prediction of tumour volume and pathological stage in radical prostatectomy specimens is not improved by taking more prostate needle-biopsy cores

OBJECTIVE

To determine what, if any, additional prognostic information is available from the prostate needle biopsy by comparing the number of biopsy cores obtained with the pathology assessed from the radical retropubic prostatectomy (RRP) specimen.

PATIENTS AND METHODS

The results from 135 consecutive patients who underwent RRP at a single institution were reviewed. Needle biopsy information (number of cores, percentage of positive cores, laterality of the positive cores, and Gleason sum) were compared with the pathological data of the RRP specimen, including stage, Gleason sum and tumour volume. Patients were further stratified into those with six or fewer cores (96 men) or more than six cores (39 men). Clinical data, including biopsy information and pathological findings, were compared using univariate and multivariate models.

RESULTS

Overall, univariate analysis showed that the total prostate-specific antigen (PSA) level, number of positive cores, bilateral positive cores and percentage of positive cores were directly correlated with tumour volume (P=0.01). Also, PSA and percentage of positive cores were directly correlated with extracapsular extension (P=0.008 and P=0.01, respectively). In the multivariate model, the most important independent predictors of RRP tumour volume and pathological stage were the preoperative PSA level and percentage of cancer in the biopsy (P<0.01). There was no significant relationship between the number of cores obtained and the predicted pathology of the RRP specimen. There were no differences in the number of positive cores, bilateral positive cores or percentage tumour in the cores between men with more or less than six biopsies. In men with more than six core biopsies, there was no significant increase in prognostic information for tumour volume and extracapsular extension, or a correlation between the Gleason sum on biopsy and the RRP specimen. Taking more than six biopsies did not result in a significantly greater detection of potentially indolent tumours (defined as a tumour volume of <0.5 mL).

CONCLUSIONS

While taking more prostate needle biopsy cores seems to improve the detection of prostate cancer, there appears to be no major improvement in prognostic information over that gained from traditional sextant biopsies. Furthermore, the results suggest that the percentage of positive cores is the best predictor of both pathological stage and tumour volume, from among the information readily available from prostate needle biopsy. Given the variability in the number of cores obtained for diagnosis in clinical practice, these results add credence to the use of the percentage of positive cores in the biopsy set, with known predictors such as PSA and Gleason score, into future models that attempt to predict tumour biology.

Alterations in lipoxygenase and cyclooxygenase-2 catalytic activity and mRNA expression in prostate carcinoma

Recent studies in prostate tissues and especially cell lines have suggested roles for arachidonic acid (AA) metabolizing enzymes in prostate adenocarcinoma (Pca) development or progression. The goal of this study was to more fully characterize lipoxygenase (LOX) and cyclooxygenase-2 (COX-2) gene expression and AA metabolism in benign and malignant prostate using snap-frozen tissues obtained intraoperatively and mRNA analyses and enzyme assays. Formation of 15-hydroxyeicosatetraenoic acid (15-HETE) was detected in 23/29 benign samples and 15-LOX-2 mRNA was detected in 21/25 benign samples. In pairs of pure benign and Pca from the same patients, 15-HETE production and 15-LOX-2 mRNA were reduced in Pca versus benign in 9/14 (P=.04) and 14/17 (P=.002), respectively. Under the same conditions, neither 5-HETE nor 12-HETE formation was detectable in 29 benign and 24 tumor samples; with a more sensitive assay, traces were detected in some samples, but there was no clear association with tumor tissue. COX-2 mRNA was detected by nuclease protection assay in 7/16 benign samples and 5/16 tumors. In benign and tumor pairs from 10 patients, COX-2 was higher in tumor versus benign in only 2, with similar results by in situ hybridization. Paraffin immunoperoxidase for COX-2 was performed in whole mount sections from 87 additional radical prostatectomy specimens, with strong expression in ejaculatory duct as a positive control and corroboration with in situ hybridization. No immunostaining was detected in benign prostate or tumor in 45% of cases. Greater immunostaining in tumor versus benign was present in only 17% of cases, and correlated with high tumor grade (Gleason score 8 and 9 vs. 5 to 7). In conclusion, reduced 15-LOX-2 expression and 15-HETE formation is the most characteristic alteration of AA metabolism in Pca. Increased 12-HETE and 5-HETE formation in Pca were not discernible. Increased COX-2 expression is not a typical abnormality in Pca in general, but occurs in high-grade tumors.

15S-Hydroxyeicosatetraenoic acid activates peroxisome proliferator-activated receptor gamma and inhibits proliferation in PC3 prostate carcinoma cells

15-Lipoxygenase (15-LOX)-2 is expressed in benign prostate secretory cells and benign prostate produces 15S-hydroxyeicosatetraenoic acid (15S-HETE) from exogenous arachidonic acid (AA). In contrast, 15S-LOX-2 and 15S-HETE formation are reduced in prostate carcinoma (Pca). The mechanisms whereby reduced 15-LOX-2 may contribute to Pca development or progression are not known. We investigated the expression of peroxisome proliferator-activated receptor (PPAR) gamma in benign and malignant prostate tissues and the ability of 15S-HETE to activate PPARgamma-dependent transcription and modulate proliferation of the Pca cell line PC3. In contrast to benign prostate and similar to most Pca tissues, 15-LOX-2 mRNA was not detected in PC3 cells, and they did not produce detectable 15-HETE from [14C]AA. By reverse transcription-PCR, PPARgamma mRNA was present in 18 of 18 benign and 9 of 9 tumor specimens. The PPARgamma ligand BRL 49653 and 15S-HETE caused a dose-dependent inhibition of PC3 proliferation in a 14-day soft agar colony-forming assay (IC50 of 3 and 30 microM, respectively). 15S-HETE (10 microM) caused greater inhibition than 10 microM 15R-HETE. At 3 days, BRL 49653 and 15S-HETE caused a slight increase in cells in G0-G1 and a corresponding decrease in cells in S phase. In PC3 cells transiently transfected with a luciferase reporter linked to a PPAR response element, 1 microM BRL 49653 and 10 microM 15S-HETE caused approximately threefold and greater than twofold induction of PPAR-dependent transcription, respectively. By quantitative real-time reverse transcription-PCR and Northern analysis, 3-day treatment with BRL 49653 and 15S-HETE caused a reduction of PPARgamma expression but a marked up-regulation of the PPAR response element containing adipocyte type fatty acid binding protein. These results support the hypothesis that 15-LOX-2-derived 15S-HETE may constitute an endogenous ligand for PPARgamma in the prostate and that loss of this pathway by reduced expression of 15-LOX-2 may contribute to increased proliferation and reduced differentiation in prostate carcinoma.

Reduced 15-lipoxygenase-2 immunostaining in prostate adenocarcinoma: correlation with grade and expression in high-grade prostatic intraepithelial neoplasia

Arachidonic acid (AA) metabolites are implicated in the oncogenesis of several tumors, including prostate cancer. 15-Lipoxygenase-2 (15-LOX-2) is a novel AA-metabolizing enzyme with a limited tissue distribution, which includes prostate, lung, skin, and cornea. Previous studies have shown that 15-LOX-2 is present in benign prostate secretory cells and reduced in prostate adenocarcinoma and that production of the 15-LOX-2 metabolite 15S-hydroxyeicosatetraenoic acid is reduced in malignant compared with benign prostate. The objective of this study was to determine the frequency with which 15-LOX-2 immunostaining is reduced in prostate carcinoma and to correlate reduced expression with tumor differentiation (grade) and other pathologic parameters in radical prostatectomy specimens. Paraffin immunoperoxidase with a polyclonal antibody specific for 15-LOX-2 was performed on tumors and benign portions from 70 cases, and the percentage of tumor immunostaining for 15-LOX-2 was assessed. Whereas uniform 15-LOX-2 immunostaining was observed in secretory cells of benign glands, it was markedly reduced or absent in most adenocarcinomas: 23 of 70 tumors showed completely absent 15-LOX-2 immunostaining, and 45 of 70 cases showed negative immunostaining in more than 50% of the tumor. The extent of reduced 15-LOX-2 immunostaining correlated with tumor differentiation, with retained expression particularly in Gleason score 5 tumors versus a significant reduction of 15-LOX-2 in higher-grade tumors (mean +/- SD tumor 15-LOX-2 positive: Gleason score 5 = 67%+/-30%, Gleason score 6 = 16%+/-30%, Gleason score 7 = 23%+/-28%, Gleason score > or =8 = 41%+/-46%). In 16 cases with multifocal tumors or different foci of the same tumor with different grades, the higher-grade foci had significantly reduced 15-LOX-2 expression compared with the lower-grade foci. In peripheral zone tumors without complete loss of 15-LOX-2 expression, there was a significant inverse relationship between 15-LOX-2 immunostaining and tumor volume. There was not a significant correlation between 15-LOX-2 immunostaining and serum PSA or pathologic stage. In a subset of 27 cases, 15-LOX-2 expression in high-grade prostatic intraepithelial neoplasia (HGPIN) glands was significantly reduced compared with benign glands. These data show that in contrast to the uniform expression of 15-LOX-2 in differentiated secretory cells of benign prostate, reduced 15-LOX-2 is a common alteration in prostate carcinoma, and this correlates with tumor cell differentiation. That reduced expression is seen in HGPIN suggests that this may be an early alteration in carcinoma development.