Short-term psychosocial outcomes of adding a non-contrast abdominal computed tomography (CT) scan to the thoracic CT within lung cancer screening.

OBJECTIVES: To evaluate psychological, social, and financial outcomes amongst individuals undergoing a non-contrast abdominal computed tomography (CT) scan to screen for kidney cancer and other abdominal malignancies alongside the thoracic CT within lung cancer screening. SUBJECTS AND METHODS: The Yorkshire Kidney Screening Trial (YKST) is a feasibility study of adding a non-contrast abdominal CT scan to the thoracic CT within lung cancer screening. A total of 500 participants within the YKST, comprising all who had an abnormal CT scan and a random sample of one-third of those with a normal scan between 14/03/2022 and 24/08/2022 were sent a questionnaire at 3 and 6 months. Outcomes included the Psychological Consequences Questionnaire (PCQ), the short-form of the Spielberger State-Trait Anxiety Inventory, and the EuroQoL five Dimensions five Levels scale (EQ-5D-5L). Data were analysed using regression adjusting for participant age, sex, socioeconomic status, education, baseline quality of life (EQ-5D-5L), and ethnicity. RESULTS: A total of 380 (76%) participants returned questionnaires at 3 months and 328 (66%) at 6 months. There was no difference in any outcomes between participants with a normal scan and those with abnormal scans requiring no further action. Individuals requiring initial further investigations or referral had higher scores on the negative PCQ than those with normal scans at 3 months (standardised mean difference 0.28 sd, 95% confidence interval 0.01-0.54; P = 0.044). The difference was greater in those with anxiety or depression at baseline. No differences were seen at 6 months. CONCLUSION: Screening for kidney cancer and other abdominal malignancies using abdominal CT alongside the thoracic CT within lung cancer screening is unlikely to cause significant lasting psychosocial or financial harm to participants with incidental findings.

Long-term outcomes of image-guided ablation and laparoscopic partial nephrectomy for T1 renal cell carcinoma.

OBJECTIVE: To compare long-term outcomes and peri-operative outcomes of image-guided ablation (IGA) and laparoscopic partial nephrectomy (LPN). MATERIAL AND METHODS: This is a retrospective cohort study of localised RCC (T1a/bN0M0) patients undergoing cryoablation (CRYO), radio-frequency ablation (RFA), or LPN at our institution from 2003 to 2016. Oncological outcomes were compared using Cox regression and log-rank analysis. eGFR changes were compared using Kruskal-Wallis and Wilcoxon-rank tests. RESULTS: A total of 296 (238 T1a, 58 T1b) consecutive patients were identified; 103, 100, and 93 patients underwent CRYO, RFA, and LPN, respectively. Median follow-up time was 75, 98, and 71 months, respectively. On univariate analysis, all oncological outcomes were comparable amongst CRYO, RFA, and LPN (p > 0.05). On multivariate analysis, T1a patients undergoing RFA had improved local recurrence-free survival (LRFS) (HR 0.002, 95% CI 0.00-0.11, p = 0.003) and metastasis-free survival (HR 0.002, 95% CI 0.00-0.52, p = 0.029) compared to LPN. In T1a and T1b patients combined, both CRYO (HR 0.07, 95% CI 0.01-0.73, p = 0.026) and RFA (HR 0.04, 95% CI 0.03-0.48, p = 0.011) had improved LRFS rates. Patients undergoing CRYO and RFA had a significantly smaller median decrease in eGFR post-operatively compared to LPN (T1a: p < 0.001; T1b: p = 0.047). Limitations include retrospective design and limited statistical power. CONCLUSIONS: IGA is potentially as good as LPN in oncological durability. IGA preserves kidney function significantly better than LPN. More studies with larger sample size should be performed to establish IGA as a first-line treatment alongside LPN. KEY POINTS: • Ablative therapies are alternatives to partial nephrectomy for managing small renal cell carcinomas. • This study reports long-term outcomes of image-guided ablation versus partial nephrectomy. • Ablative therapies have comparable oncological durability and better renal function preservation compared to partial nephrectomy.

Irreversible electroporation (IRE) in renal cell carcinoma (RCC): a mid-term clinical experience.

OBJECTIVES: To evaluate the safety and efficacy of CT-guided IRE of clinical T1a (cT1a) renal tumours close to vital structures and to assess factors that may influence the technical success and early oncological durability. METHODS: CT-guided IRE (2015-2020) was prospectively evaluated. Patients' demographics, technical details/success, Clavien-Dindo (CD) classification of complications (I-V) and oncological outcome were collated. Statistical analysis was performed to determine variables associated with complications. The overall 2- and 3-year cancer-specific (CS), local recurrence-free (LRF) and metastasis-free (MF) survival rates are presented using the Kaplan-Meier curves. RESULTS: Thirty cT1a RCCs (biopsy-proven/known VHL disease) in 26 patients (age 32-81 years) were treated with IRE. The mean tumour size was 2.5 cm and the median follow-up was 37 months. The primary technical success rate was 73.3%, where 22 RCCs were completely IRE ablated. Seven residual diseases were successfully ablated with cryoablation, achieving an overall technical success rate of 97%. One patient did not have repeat treatment as he died from unexpected stroke at 4-month post-IRE. One patient had CD-III complication with a proximal ureteric injury. Five patients developed > 25% reduction of eGFR immediately post-IRE. All patients have preservation of renal function without the requirement for renal dialysis. The overall 2- and 3-year CS, LRF and MF survival rates are 89%, 96%, 91% and 87%. CONCLUSION: CT-guided IRE in cT1a RCC is safe with acceptable complications. The primary technical success rate was suboptimal due to the early operator's learning curve, and long-term follow-up is required to validate the IRE oncological durability. KEY POINTS: • Irreversible electroporation should only be considered when surgery or image-guided thermal ablation is not an option for small renal cancer. • This non-thermal technique is safe in the treatment of small renal cancer and the primary technical success rate was 73.3%. • This can be used when renal cancer is close to important structure.

Acceptability of adding a non-contrast abdominal CT scan to screen for kidney cancer and other abdominal pathology within a community-based CT screening programme for lung cancer: A qualitative study.

OBJECTIVES: The Yorkshire Kidney Screening Trial (YKST) is a feasibility study of adding non-contrast abdominal CT scanning to screen for kidney cancer and other abdominal malignancies to community-based CT screening for lung cancer within the Yorkshire Lung Screening Trial (YLST). This study explored the acceptability of the combined screening approach to participants and healthcare professionals (HCPs) involved in the trial. METHODS: We conducted semi-structured interviews with eight HCPs and 25 participants returning for the second round of scanning within YLST, 20 who had taken up the offer of the additional abdominal CT scan and five who had declined. Transcripts were analysed using thematic analysis, guided by the Theoretical Framework of Acceptability. RESULTS: Overall, combining the offer of a non-contrast abdominal CT scan alongside the low-dose thoracic CT was considered acceptable to participants, including those who had declined the abdominal scan. The offer of the additional scan made sense and fitted well within the process, and participants could see benefits in terms of efficiency, cost and convenience both for themselves as individuals and also more widely for the NHS. Almost all participants made an instant decision at the point of initial invitation based more on trust and emotions than the information provided. Despite this, there was a clear desire for more time to decide whether to accept the scan or not. HCPs also raised concerns about the burden on the study team and wider healthcare system arising from additional workload both within the screening process and downstream following findings on the abdominal CT scan. CONCLUSIONS: Adding a non-contrast abdominal CT scan to community-based CT screening for lung cancer is acceptable to both participants and healthcare professionals. Giving potential participants prior notice and having clear pathways for downstream management of findings will be important if it is to be offered more widely.

Abdominal Noncontrast Computed Tomography Scanning to Screen for Kidney Cancer and Other Abdominal Pathology Within Community-based Computed Tomography Screening for Lung Cancer: Results of the Yorkshire Kidney Screening Trial.

BACKGROUND AND OBJECTIVE: The Yorkshire Kidney Screening Trial (YKST) assessed the feasibility of adding abdominal noncontrast computed tomography (NCCT) to lung cancer screening to screen for kidney cancer and other abdominal pathology. METHODS: A prospective diagnostic study offered abdominal NCCT to 55-80-yr-old ever-smokers attending a UK randomised lung cancer screening trial (May 2021 to October 2022). The exclusion criteria were dementia, frailty, previous kidney/lung cancer, and computed tomography (CT) of the abdomen and thorax within previous 6 and 12 mo, respectively. Six-month follow-up was undertaken. KEY FINDINGS AND LIMITATIONS: A total of 4438 people attended lung screening, of whom 4309 (97%) were eligible for and 4019 (93%) accepted abdominal NCCT. Only 3.9% respondents regretted participating. The additional time to conduct the YKST processes was 13.3 min. Of the participants, 2586 (64%) had a normal abdominal NCCT, whilst 787 (20%) required an abdominal NCCT imaging review but no further action and 611 (15%) required further evaluation (investigations and/or clinic). Of the participants, 211 (5.3%) had a new serious finding, including 25 (0.62%) with a renal mass/complex cyst, of whom ten (0.25%) had histologically proven kidney cancer; ten (0.25%) with other cancers; and 60 (1.5%) with abdominal aortic aneurysms (AAAs). Twenty-five (0.62%) participants had treatment with curative intent. Of the participants, 1017 (25%) had nonserious findings, most commonly benign renal cysts (727 [18%]), whereas only 259 (6.4%) had nonserious findings requiring further tests. The number needed to screen to detect one serious abdominal finding was 18; it was 93 to detect one suspicious renal lesion and 402 to detect one histologically confirmed renal cancer. Limitations of the cohort were fixed age range and being prior lung cancer screening attendees. CONCLUSIONS AND CLINICAL IMPLICATIONS: In this first prospective risk-stratified screening study of abdominal NCCT offered alongside CT thorax, uptake and participant satisfaction were high. The prevalence of serious findings, cancers, and AAAs, is in the range of established screening programmes such as bowel cancer. Longer-term outcomes and cost effectiveness should now be evaluated.

Is there a correlation between urolithiasis in horseshoe kidneys and isthmus thickness or renal angulation?

BACKGROUND: Stone disease is a common complication of horseshoe kidneys (HSK). There are currently limited studies that examine the relationship between HSK anatomy and stone formation. We aim to determine if there is such an association by measuring the isthmus size and renal angulation in both stone and non-stone forming HSK using computed tomography (CT). METHOD: This is a retrospective study performed at a single tertiary centre. Using the radiological information system, all CT reports between 01 January 2010 and 31 December 2015 were searched for the keyword 'horseshoe' on the radiological information system. This produced a list of 285 reports. Each report and image packet of these 285 studies were reviewed to confirm the presence of an HSK and duplicate patients from multiple examinations were highlighted. One hundred and thirty-eight unique HSK patients were obtained and the studies were assessed for the presence or absence of stones. A total of 112 HSK were found; 88 of which contained no stone and 24 with stone. Angle measurements and isthmus size were measured on these kidneys. As axial images are obtained as standard in all cases, these measurements were all obtained in the axial plane. All parameters were measured and recorded manually by one person so as to reduce inter-observer variability. RESULTS: Isthmus size varied widely, measuring from 2 to 39 mm. Right renal angle ranged from 51 to 158°, left 38 to 152°. CONCLUSION: The isthmus size and renal angle measurements were not found to be significant determinants for stone disease in our patient population.

The Prognostic Value of Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio for Small Renal Cell Carcinomas after Image-Guided Cryoablation or Radio-Frequency Ablation.

There is a lack of cheap and effective biomarkers for the prediction of renal cancer outcomes post-image-guided ablation. This is a retrospective study of patients with localised small renal cell cancer (T1a or T1b) undergoing cryoablation or radiofrequency ablation (RFA) at our institution from 2003 to 2016. A total of 203 patients were included in the analysis. In the multivariable analysis, patients with raised neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) pre-operatively, post-operatively and peri-operatively are associated with significantly worsened cancer-specific survival, overall survival and metastasis-free survival. Furthermore, an increased PLR pre-operatively is also associated with increased odds of a larger than 25% drop in renal function post-operatively. In conclusion, NLR and PLR are effective prognostic factors in predicting oncological outcomes and peri-operative outcomes; however, larger external datasets should be used to validate the findings prior to clinical application.

Application of Genomic Sequencing to Refine Patient Stratification for Adjuvant Therapy in Renal Cell Carcinoma.

PURPOSE: Patients with resected localized clear-cell renal cell carcinoma (ccRCC) remain at variable risk of recurrence. Incorporation of biomarkers may refine risk prediction and inform adjuvant treatment decisions. We explored the role of tumor genomics in this setting, leveraging the largest cohort to date of localized ccRCC tissues subjected to targeted gene sequencing. EXPERIMENTAL DESIGN: The somatic mutation status of 12 genes was determined in 943 ccRCC cases from a multinational cohort of patients, and associations to outcomes were examined in a Discovery (n = 469) and Validation (n = 474) framework. RESULTS: Tumors containing a von-Hippel Lindau (VHL) mutation alone were associated with significantly improved outcomes in comparison with tumors containing a VHL plus additional mutations. Within the Discovery cohort, those with VHL+0, VHL+1, VHL+2, and VHL+≥3 tumors had disease-free survival (DFS) rates of 90.8%, 80.1%, 68.2%, and 50.7% respectively, at 5 years. This trend was replicated in the Validation cohort. Notably, these genomically defined groups were independent of tumor mutational burden. Amongst patients eligible for adjuvant therapy, those with a VHL+0 tumor (29%) had a 5-year DFS rate of 79.3% and could, therefore, potentially be spared further treatment. Conversely, patients with VHL+2 and VHL+≥3 tumors (32%) had equivalent DFS rates of 45.6% and 35.3%, respectively, and should be prioritized for adjuvant therapy. CONCLUSIONS: Genomic characterization of ccRCC identified biologically distinct groups of patients with divergent relapse rates. These groups account for the ∼80% of cases with VHL mutations and could be used to personalize adjuvant treatment discussions with patients as well as inform future adjuvant trial design.

Multimodal image-guided ablation on management of renal cancer in Von-Hippel-Lindau syndrome patients from 2004 to 2021 at a specialist centre: A longitudinal observational study.

OBJECTIVES: To analyse the safety, technical feasibility, long-term renal function and oncological outcome of multimodal technologies in image-guided ablation (IGA) for renal cancer in Von-Hippel-Lindau (VHL) patients, and to evaluate factors that may influence the outcome. METHODS: Retrospective analysis of a prospective database of VHL patients who underwent IGA at a specialist centre. Patient's demographics, treatment energy, peri-operative outcome and oncological outcomes were recorded. Statistical analysis was performed to determine factors associated with complication and renal function reduction. The overall, 5 and 10-year cancer specific (CS), local recurrence-free (LRF) and metastasis-free (MF) survival rates were presented with Kaplan-Meier Curves. RESULTS: From 2004 to 2021, 17 VHL patients (age 21-68.2) with a mean (±SD) RCC size of 2.06 ± 0.92 cm received IGA. Median (IQR) RCCs per patient was 3 (2-4) over the course of follow up. Fifty-four RCCs were treated using radiofrequency ablation (n = 11), cryoablation (n = 38) and irreversible electroporation (n = 8) in 50 sessions. Primary and overall technical success rate were 94.4% (51/54) and 98% (53/54). One CD-III complication with proximal ureteric injury. Five patients in seven treatment sessions experienced a >25% reduction of eGFR immediately post-IGA. All patients have preservation of renal function at a median follow-up of 79 (51-134) months. The 5 and 10-year CS, LRF and MF survival rates are 100%, 97.8% and 100%. Whilst, the 5 and 10-year overall survival rate are100% and 90%. CONCLUSION: Multimodal IGA of de novo RCC for VHL patients is safe and has provided long term preservation of renal function and robust oncological durability.

The Yorkshire Kidney Screening Trial (YKST): protocol for a feasibility study of adding non-contrast abdominal CT scanning to screen for kidney cancer and other abdominal pathology within a trial of community-based CT screening for lung cancer.

INTRODUCTION: Kidney cancer (renal cell cancer (RCC)) is the seventh most common cancer in the UK. As RCC is largely curable if detected at an early stage and most patients have no symptoms, there is international interest in evaluating a screening programme for RCC. The Yorkshire Kidney Screening Trial (YKST) will assess the feasibility of adding non-contrast abdominal CT scanning to screen for RCC and other abdominal pathology within the Yorkshire Lung Screening Trial (YLST), a randomised trial of community-based CT screening for lung cancer. METHODS AND ANALYSIS: In YLST, ever-smokers aged 55-80 years registered with a general practice in Leeds have been randomised to a Lung Health Check assessment, including a thoracic low-dose CT (LDCT) for those at high risk of lung cancer, or routine care. YLST participants randomised to the Lung Health Check arm who attend for the second round of screening at 2 years without a history of RCC or abdominal CT scan within the previous 6 months will be invited to take part in YKST. We anticipate inviting 4700 participants. Those who consent will have an abdominal CT immediately following their YLST thoracic LDCT. A subset of participants and the healthcare workers involved will be invited to take part in a qualitative interview. Primary objectives are to quantify the uptake of the abdominal CT, assess the acceptability of the combined screening approach and pilot the majority of procedures for a subsequent randomised controlled trial of RCC screening within lung cancer screening. ETHICS AND DISSEMINATION: YKST was approved by the North West-Preston Research Ethics Committee (21/NW/0021), and the Health Research Authority on 3 February 2021. Trial results will be disseminated at clinical meetings, in peer-reviewed journals and to policy-makers. Findings will be made available to participants via the study website (www.YKST.org). TRIAL REGISTRATION NUMBERS: NCT05005195 and ISRCTN18055040.

Iatrogenic ureteric stricture post image guided renal cryoablation in a patient with von hippel-lindau syndrome.

A 53-year-old lady is known to have Von Hippel-Lindau syndrome with a long history of previous renal cell carcinomas (RCCs) in both kidneys. She was treated by partial nephrectomy for a right peripheral RCC and subsequently image guided radiofrequency ablation (RFA) of a left central RCC. She developed another de novo RCC adjacent to the right pelvic-ureteric junction (PUJ) 4 years after the initial RFA. Due to the close proximity to the PUJ and visibility of an ice ball with cryoablation (CRYO), the consensus from the MDT was that CRYO would be safer than RFA and she subsequently underwent percutaneous image guided CRYO to treat the small de novo RCC. Unfortunately, during the 1-month imaging follow up, she developed moderate hydronephrosis and a ureteric stricture needing long-term ureteric stent management. This case highlights the risk of ureteric injury caused by the thermal effect of the ice ball during image guided renal CRYO. Therefore, it is vital that all interventional radiologists adopt various manoeuvres to protect the ureter from the ice ball during CRYO in order to avoid the development of latent ureteric stricture.

Challenges of early renal cancer detection: symptom patterns and incidental diagnosis rate in a multicentre prospective UK cohort of patients presenting with suspected renal cancer.

OBJECTIVES: To describe the frequency and nature of symptoms in patients presenting with suspected renal cell carcinoma (RCC) and examine their reliability in achieving early diagnosis. DESIGN: Multicentre prospective observational cohort study. SETTING AND PARTICIPANTS: Eleven UK centres recruiting patients presenting with suspected newly diagnosed RCC. Symptoms reported by patients were recorded and reviewed. Comprehensive clinico-pathological and outcome data were also collected. OUTCOMES: Type and frequency of reported symptoms, incidental diagnosis rate, metastasis-free survival and cancer-specific survival. RESULTS: Of 706 patients recruited between 2011 and 2014, 608 patients with a confirmed RCC formed the primary study population. The majority (60%) of patients were diagnosed incidentally. 87% of patients with stage Ia and 36% with stage III or IV disease presented incidentally. Visible haematuria was reported in 23% of patients and was commonly associated with advanced disease (49% had stage III or IV disease). Symptomatic presentation was associated with poorer outcomes, likely reflecting the presence of higher stage disease. Symptom patterns among the 54 patients subsequently found to have a benign renal mass were similar to those with a confirmed RCC. CONCLUSIONS: Raising public awareness of RCC-related symptoms as a strategy to improve early detection rates is limited by the fact that related symptoms are relatively uncommon and often associated with advanced disease. Greater attention must be paid to the feasibility of screening strategies and the identification of circulating diagnostic biomarkers.

UK Multicenter Prospective Evaluation of the Leibovich Score in Localized Renal Cell Carcinoma: Performance has Altered Over Time.

OBJECTIVE: To examine changes in outcome by the Leibovich score using contemporary and historic cohorts of patients presenting with renal cell carcinoma (RCC) PATIENTS AND METHODS: Prospective observational multicenter cohort study, recruiting patients with suspected newly diagnosed RCC. A historical cohort of patients was examined for comparison. Metastasis-free survival (MFS) formed the primary outcome measure. Model discrimination and calibration were evaluated using Cox proportional hazard regression and the Kaplan-Meier method. Overall performance of the Leibovich model was assessed by estimating explained variation. RESULTS: Seven hundred and six patients were recruited between 2011 and 2014 and RCC confirmed in 608 (86%) patients. Application of the Leibovich score to patients with localized clear cell RCC in this contemporary cohort demonstrated good model discrimination (c-index = 0.77) but suboptimal calibration, with improved MFS for intermediate- and high-risk patients (5-year MFS 85% and 50%, respectively) compared to the original Leibovich cohort (74% and 31%) and a historic (1998-2006) UK cohort (76% and 37%). The proportion of variation in outcome explained by the model is low and has declined over time (28% historic vs 22% contemporary UK cohort). CONCLUSION: Prognostic models are widely employed in patients with localized RCC to guide surveillance intensity and clinical trial selection. However, the majority of the variation in outcome remains unexplained by the Leibovich model and, over time, MFS rates among intermediate- and high-risk classified patients have altered. These findings are likely to have implications for all such models used in this setting.

Urolithiasis in inflammatory bowel disease and bariatric surgery.

AIM: To analyse current literature focusing on pathogenesis and therapeutic aspects of urolithiasis with inflammatory bowel disease (IBD) and following bariatric surgery. METHODS: A systematic literature search was performed using PubMed, supplemented with additional references. Studies assessing the association of IBD or bariatric surgery with renal stones in both paediatric and adulthood were included. RESULTS: Certain types of stones are seen more frequently with IBD. Hyperoxaluria and hypocitraturia are the main metabolic changes responsible for urolithiasis. The incidence of renal stones in malabsorptive types of bariatric surgery such as gastric bypass is high; this is not as common in modern restrictive surgical methods. Preventative methods and urine alkalinisation have been shown to be beneficial. CONCLUSION: Both conditions are associated with renal stones. Patients' counselling and prevention strategies are the mainstay of urolithiasis management in these patients.

Modified supine percutaneous nephrolithotomy for large kidney and ureteral stones: technique and results.

BACKGROUND: Percutaneous nephrolithotomy (PCNL) is the standard treatment for kidney stones >2cm. Recently, a novel approach in the modified supine lithotomy position has been developed. OBJECTIVE: To demonstrate with a video our technique of supine PCNL (sPCNL) and present our experience. DESIGN, SETTING, AND PARTICIPANTS: From September 2009 to August 2010, 47 consecutive patients were prospectively evaluated. There were 31 single, 9 multiple, and 7 staghorn stones. The mean body mass index was 26.1±5 (range: 17.3-45.7), the mean stone size was 29.6±15.3mm (range: 10-75), and patients' American Society of Anesthesiologists scores were 1, 2, and 3 in 31, 11, and 5 cases, respectively. SURGICAL PROCEDURE: Patients were positioned in Galdakao-modified supine Valdivia position. The details of the technique are shown in the film. MEASUREMENTS: Success was defined as patients free of stones or with residual stone fragments <4mm. RESULTS AND LIMITATIONS: Average operative room occupation time was 123.5±51.2min (range: 50-245). In the single, multiple, and staghorn stone groups, the immediate success rate after sPCNL was 90%, 78%, and 43%, respectively. Complications included one fever, two incidents of pyelonephritis, one renal colic, two urinary fistulae, one postoperative hemorrhage, and one incident of acute urinary retention. Mean hospital stay was 3.4±1.9 d (range: 2-12). Nine patients (19%) had a secondary procedure (extracorporeal shock wave lithotripsy or flexible ureterorenoscopy). At 3 mo, the success rate was 97%, 100%, and 100% in the single, multiple, and staghorn stone groups, respectively. However, the limitation of this study is its design, which is descriptive rather than comparative. CONCLUSIONS: sPCNL is a safe and reproducible method. It offers the advantage of simultaneous retrograde and antegrade endoscopic combined intrarenal surgery, and we believe it is a further advancement in stone management. In addition, it is easier from the anesthetist point of view than the traditional prone approach. In our hands, it meant a simplification of the operative technique, resulting in a more time-efficient procedure.

Out-patient flexible cystoscopy using a disposable slide-on endosheath system.

INTRODUCTION: The aim of this study was to investigate the feasibility of out-patient flexible cystoscopy. PATIENTS AND METHODS: Twenty-seven patients awaiting diagnostic or check cystoscopy in Leeds, UK were invited to undergo out-patient flexible cystoscopy using a CST-2000 Flexible Cystoscope (Vision Sciences; Natick, MA, USA) using the sterile single-use slide-on(trade mark) disposable endosheath endoscope system (EndoSheath); Vision Sciences). The performance of the cystoscope was evaluated, and the patients' experiences were documented using a questionnaire. RESULTS: The out-patient setting proved to be ideal for flexible cystoscopy. The cystoscope was rated highly for image quality, ease of use and handling. All patients complimented us on the service and preferred out-patients to a day-ward or theatre attendance. CONCLUSIONS: This study demonstrates that it is possible to perform out-patient flexible cystoscopy safely, economically and efficiently with the aid of a disposable endoscope system.

In vitro assessment of decellularized porcine dermis as a matrix for urinary tract reconstruction.

OBJECTIVES: To assess the potential of Permacol (Tissue Science Laboratories, Swillington, UK), a natural matrix derived from decellularized porcine dermis, as a matrix for urological tissue engineering, and thus to develop an in vitro regimen for assessing the biocompatibility of potential biomaterials before experimentation in animal models. MATERIALS AND METHODS: Urinary tract-derived normal human urothelial (NHU) and smooth muscle (SM) cells were grown in monoculture as autologous cell lines. Permacol was assessed for its ability to support colonization by NHU and SM cells. The failure of the Permacol matrix to be infiltrated by SM cells was further investigated using the highly invasive EJ bladder cancer cell line. RESULTS: NHU cells readily attached and grew as a monolayer on the surface of Permacol. Cells stratified when the culture medium was supplemented with 2 mmol/L calcium. EJ cells initially grew on the surface and subsequently invaded the matrix, while SM cells only colonized the surface of Permacol when cocultured with NHU cells. Cytoxicity, evaluated by contact inhibition and conditioned-medium assays, excluded the presence of soluble toxins in the biomaterial. CONCLUSIONS: We developed a simple, reproducible and rigorous regimen for assessing potential biomaterials in vitro. Applying this system might reduce the use of animals and help to identify causes of potential bio-incompatibility. The inability of SM cells to penetrate the Permacol matrix suggests that required matrix-bound signalling factors are absent, possibly as a result of the procedures used for processing Permacol. Identifying the key regulatory factors that regulate SM cell growth and orchestrate regenerative processes in the urinary tract will be important for developing suitable biomaterials for the bladder.