Mapping single-cell transcriptomes in the intra-tumoral and associated territories of kidney cancer.

Tumor behavior is intricately dependent on the oncogenic properties of cancer cells and their multi-cellular interactions. To understand these dependencies within the wider microenvironment, we studied over 270,000 single-cell transcriptomes and 100 microdissected whole exomes from 12 patients with kidney tumors, prior to validation using spatial transcriptomics. Tissues were sampled from multiple regions of the tumor core, the tumor-normal interface, normal surrounding tissues, and peripheral blood. We find that the tissue-type location of CD8+ T cell clonotypes largely defines their exhaustion state with intra-tumoral spatial heterogeneity that is not well explained by somatic heterogeneity. De novo mutation calling from single-cell RNA-sequencing data allows us to broadly infer the clonality of stromal cells and lineage-trace myeloid cell development. We report six conserved meta-programs that distinguish tumor cell function, and find an epithelial-mesenchymal transition meta-program highly enriched at the tumor-normal interface that co-localizes with IL1B-expressing macrophages, offering a potential therapeutic target.

Hyperpolarized 13C-Pyruvate Metabolism as a Surrogate for Tumor Grade and Poor Outcome in Renal Cell Carcinoma-A Proof of Principle Study.

Differentiating aggressive clear cell renal cell carcinoma (ccRCC) from indolent lesions is challenging using conventional imaging. This work prospectively compared the metabolic imaging phenotype of renal tumors using carbon-13 MRI following injection of hyperpolarized [1-13C]pyruvate (HP-13C-MRI) and validated these findings with histopathology. Nine patients with treatment-naïve renal tumors (6 ccRCCs, 1 liposarcoma, 1 pheochromocytoma, 1 oncocytoma) underwent pre-operative HP-13C-MRI and conventional proton (1H) MRI. Multi-regional tissue samples were collected using patient-specific 3D-printed tumor molds for spatial registration between imaging and molecular analysis. The apparent exchange rate constant (kPL) between 13C-pyruvate and 13C-lactate was calculated. Immunohistochemistry for the pyruvate transporter (MCT1) from 44 multi-regional samples, as well as associations between MCT1 expression and outcome in the TCGA-KIRC dataset, were investigated. Increasing kPL in ccRCC was correlated with increasing overall tumor grade (ρ = 0.92, p = 0.009) and MCT1 expression (r = 0.89, p = 0.016), with similar results acquired from the multi-regional analysis. Conventional 1H-MRI parameters did not discriminate tumor grades. The correlation between MCT1 and ccRCC grade was confirmed within a TCGA dataset (p < 0.001), where MCT1 expression was a predictor of overall and disease-free survival. In conclusion, metabolic imaging using HP-13C-MRI differentiates tumor aggressiveness in ccRCC and correlates with the expression of MCT1, a predictor of survival. HP-13C-MRI may non-invasively characterize metabolic phenotypes within renal cancer.

Dynamic biomarker and imaging changes from a phase II study of pre- and post-surgical sunitinib.

OBJECTIVE: To explore translational biological and imaging biomarkers for sunitinib treatment before and after debulking nephrectomy in the NeoSun (European Union Drug Regulating Authorities Clinical Trials Database [EudraCT] number: 2005-004502-82) single-centre, single-arm, single-agent, Phase II trial. PATIENTS AND METHODS: Treatment-naïve patients with metastatic renal cell carcinoma (mRCC) received 50 mg once daily sunitinib for 12 days pre-surgically, then post-surgery on 4 week-on, 2 week-off, repeating 6-week cycles until disease progression in a single arm phase II trial. Structural and dynamic contrast-enhanced magnet resonance imaging (DCE-MRI) and research blood sampling were performed at baseline and after 12 days. Computed tomography imaging was performed at baseline and post-surgery then every two cycles. The primary endpoint was objective response rate (Response Evaluation Criteria In Solid Tumors [RECIST]) excluding the resected kidney. Secondary endpoints included changes in DCE-MRI of the tumour following pre-surgery sunitinib, overall survival (OS), progression-free survival (PFS), response duration, surgical morbidity/mortality, and toxicity. Translational and imaging endpoints were exploratory. RESULTS: A total of 14 patients received pre-surgery sunitinib, 71% (10/14) took the planned 12 doses. All underwent nephrectomy, and 13 recommenced sunitinib postoperatively. In all, 58.3% (seven of 12) of patients achieved partial or complete response (PR or CR) (95% confidence interval 27.7-84.8%). The median OS was 33.7 months and median PFS was 15.7 months. Amongst those achieving a PR or CR, the median response duration was 8.7 months. No unexpected surgical complications, sunitinib-related toxicities, or surgical delays occurred. Within the translational endpoints, pre-surgical sunitinib significantly increased necrosis, and reduced cluster of differentiation-31 (CD31), Ki67, circulating vascular endothelial growth factor-C (VEGF-C), and transfer constant (KTrans , measured using DCE-MRI; all P < 0.05). There was a trend for improved OS in patients with high baseline plasma VEGF-C expression (P = 0.02). Reduction in radiological tumour volume after pre-surgical sunitinib correlated with high percentage of solid tumour components at baseline (Spearman's coefficient ρ = 0.69, P = 0.02). Conversely, the percentage tumour volume reduction correlated with lower baseline percentage necrosis (coefficient = -0.51, P = 0.03). CONCLUSION: Neoadjuvant studies such as the NeoSun can safely and effectively explore translational biological and imaging endpoints.

Comprehensive characterization of cell-free tumor DNA in plasma and urine of patients with renal tumors.

BACKGROUND: Cell-free tumor-derived DNA (ctDNA) allows non-invasive monitoring of cancers, but its utility in renal cell cancer (RCC) has not been established. METHODS: Here, a combination of untargeted and targeted sequencing methods, applied to two independent cohorts of patients (n = 91) with various renal tumor subtypes, were used to determine ctDNA content in plasma and urine. RESULTS: Our data revealed lower plasma ctDNA levels in RCC relative to other cancers of similar size and stage, with untargeted detection in 27.5% of patients from both cohorts. A sensitive personalized approach, applied to plasma and urine from select patients (n = 22) improved detection to ~ 50%, including in patients with early-stage disease and even benign lesions. Detection in plasma, but not urine, was more frequent amongst patients with larger tumors and in those patients with venous tumor thrombus. With data from one extensively characterized patient, we observed that plasma and, for the first time, urine ctDNA may better represent tumor heterogeneity than a single tissue biopsy. Furthermore, in a subset of patients (n = 16), longitudinal sampling revealed that ctDNA can track disease course and may pre-empt radiological identification of minimal residual disease or disease progression on systemic therapy. Additional datasets will be required to validate these findings. CONCLUSIONS: These data highlight RCC as a ctDNA-low malignancy. The biological reasons for this are yet to be determined. Nonetheless, our findings indicate potential clinical utility in the management of patients with renal tumors, provided improvement in isolation and detection approaches.

Impact of hospital nephrectomy volume on intermediate- to long-term survival in renal cell carcinoma.

OBJECTIVE: To evaluate the relationship between hospital volume and intermediate- and long-term patient survival for patients undergoing nephrectomy for renal cell carcinoma (RCC). PATIENTS AND METHODS: Adult patients with RCC treated with nephrectomy between 2000 and 2010 were identified from the English Hospital Episode Statistics database and National Cancer Data Repository. Patients with nodal or metastatic disease were excluded. Hospitals were categorised into low- (LV; <20 cases/year), medium- (20-39 cases/year) and high-volume (HV; ≥40 cases/year), based on annual cases of RCC nephrectomy. Multivariable Cox regression analyses were used to calculate hazard ratios (HRs) for all-cause mortality by hospital volume, adjusting for patient, tumour and surgical characteristics. We assessed conditional survival over three follow-up periods: short (30 days to 1 year), intermediate (1-3 years) and long (3-5 years). We additionally explored whether associations between volume and outcomes varied by tumour stage. RESULTS: A total of 12 912 patients were included. Patients in HV hospitals had a 34% reduction in mortality risks up to 1 year compared to those in LV hospitals (HR 0.66, 95% confidence interval 0.53-0.83; P < 0.01). Assuming causality, treatment in HV hospitals was associated with one fewer death in every 71 patients treated. Benefit of nephrectomy centralisation did not change with higher T stage (P = 0.17). No significant association between hospital volume and survival was observed beyond the first year. CONCLUSIONS: Nephrectomy for RCC in HV hospitals was associated with improved survival for up to 1 year after treatment. Our results contribute new insights regarding the value of nephrectomy centralisation.

The VENUSS prognostic model to predict disease recurrence following surgery for non-metastatic papillary renal cell carcinoma: development and evaluation using the ASSURE prospective clinical trial cohort.

BACKGROUND: The current World Health Organization classification recognises 12 major subtypes of renal cell carcinoma (RCC). Although these subtypes differ on molecular and clinical levels, they are generally managed as the same disease, simply because they occur in the same organ. Specifically, there is a paucity of tools to risk-stratify patients with papillary RCC (PRCC). The purpose of this study was to develop and evaluate a tool to risk-stratify patients with clinically non-metastatic PRCC following curative surgery. METHODS: We studied clinicopathological variables and outcomes of 556 patients, who underwent full resection of sporadic, unilateral, non-metastatic (T1-4, N0-1, M0) PRCC at five institutions. Based on multivariable Fine-Gray competing risks regression models, we developed a prognostic scoring system to predict disease recurrence. This was further evaluated in the 150 PRCC patients recruited to the ASSURE trial. We compared the discrimination, calibration and decision-curve clinical net benefit against the Tumour, Node, Metastasis (TNM) stage group, University of California Integrated Staging System (UISS) and the 2018 Leibovich prognostic groups. RESULTS: We developed the VENUSS score from significant variables on multivariable analysis, which were the presence of VEnous tumour thrombus, NUclear grade, Size, T and N Stage. We created three risk groups based on the VENUSS score, with a 5-year cumulative incidence of recurrence equalling 2.9% in low-risk, 15.4% in intermediate-risk and 54.5% in high-risk patients. 91.7% of low-risk patients had oligometastatic recurrent disease, compared to 16.7% of intermediate-risk and 40.0% of high-risk patients. Discrimination, calibration and clinical net benefit from VENUSS appeared to be superior to UISS, TNM and Leibovich prognostic groups. CONCLUSIONS: We developed and tested a prognostic model for patients with clinically non-metastatic PRCC, which is based on routine pathological variables. This model may be superior to standard models and could be used for tailoring postoperative surveillance and defining inclusion for prospective adjuvant clinical trials.

Spatiotemporal immune zonation of the human kidney.

Tissue-resident immune cells are important for organ homeostasis and defense. The epithelium may contribute to these functions directly or by cross-talk with immune cells. We used single-cell RNA sequencing to resolve the spatiotemporal immune topology of the human kidney. We reveal anatomically defined expression patterns of immune genes within the epithelial compartment, with antimicrobial peptide transcripts evident in pelvic epithelium in the mature, but not fetal, kidney. A network of tissue-resident myeloid and lymphoid immune cells was evident in both fetal and mature kidney, with postnatal acquisition of transcriptional programs that promote infection-defense capabilities. Epithelial-immune cross-talk orchestrated localization of antibacterial macrophages and neutrophils to the regions of the kidney most susceptible to infection. Overall, our study provides a global overview of how the immune landscape of the human kidney is zonated to counter the dominant immunological challenge.

Single-cell transcriptomes from human kidneys reveal the cellular identity of renal tumors.

Messenger RNA encodes cellular function and phenotype. In the context of human cancer, it defines the identities of malignant cells and the diversity of tumor tissue. We studied 72,501 single-cell transcriptomes of human renal tumors and normal tissue from fetal, pediatric, and adult kidneys. We matched childhood Wilms tumor with specific fetal cell types, thus providing evidence for the hypothesis that Wilms tumor cells are aberrant fetal cells. In adult renal cell carcinoma, we identified a canonical cancer transcriptome that matched a little-known subtype of proximal convoluted tubular cell. Analyses of the tumor composition defined cancer-associated normal cells and delineated a complex vascular endothelial growth factor (VEGF) signaling circuit. Our findings reveal the precise cellular identities and compositions of human kidney tumors.

Time trends in service provision and survival outcomes for patients with renal cancer treated by nephrectomy in England 2000-2010.

OBJECTIVE: To describe the temporal trends in nephrectomy practice and outcomes for English patients with renal cell carcinoma (RCC). PATIENTS AND METHODS: Adult RCC nephrectomy patients treated between 2000 and 2010 were identified in the National Cancer Data Repository and Hospital Episode Statistics, and followed-up until date of death or 31 December 2015 (n = 30 763). We estimated the annual frequency for each nephrectomy type, the hospital and surgeon numbers and their case volumes. We analysed short-term surgical outcomes, as well as 1- and 5-year relative survivals. RESULTS: Annual RCC nephrectomy number increased by 66% during the study period. Hospital number decreased by 24%, whilst the median annual hospital volume increased from 10 to 23 (P < 0.01). Surgeon number increased by 27% (P < 0.01), doubling the median consultant number per hospital. The proportion of minimally invasive surgery (MIS) nephrectomies rose from 1% to 46%, whilst the proportion of nephron-sparing surgeries (NSS) increased from 5% to 16%, with 29% of all T1 disease treated with partial nephrectomy in 2010 (P < 0.01). The 30-day mortality rate halved from 2.4% to 1.1% and 90-day mortality decreased from 4.9% to 2.6% (P < 0.01). The 1-year relative survival rate increased from 86.9% to 93.4%, whilst the 5-year relative survival rate rose from 68.2% to 81.2% (P < 0.01). Improvements were most notable in patients aged ≥65 years and those with T3 and T4 disease. CONCLUSIONS: Surgical RCC management has changed considerably with nephrectomy centralisation and increased NSS and MIS. In parallel, we observed significant improvements in short- and long-term survival particularly for elderly patients and those with locally advanced disease.

Development of a Disease-Specific Ureteral Calculus Patient Reported Outcome Measurement Instrument.

INTRODUCTION: Patient reported outcome measures (PROMs) are powerful instruments to assess the impact of a disease on health from the patient's perspective. We describe the process of designing, testing, and validating the Cambridge Ureteral Stone PROM (CUSP). MATERIALS AND METHODS: Patients recently diagnosed with ureteral stones were approached for participation in focus groups, structured interviews, and test-retest validation studies. Statistical tests included Cronbach's alpha for internal consistency, Spearman's and Pearson's correlation coefficients for test-retest validity, permutation tests of equality of means and Spearman's correlation coefficients for discriminant validity. RESULTS: Forty-three patients participated in the development of the CUSP. Twenty-two patients were involved in the focus groups and structured interviews and a further 21 participated in the prospective test-retest study. Expressed comments were grouped into seven broad health domains: pain, fatigue, sleep disturbance, work and daily activities, anxiety, gastrointestinal (GI) symptoms, and urinary symptoms. Items were selected from established PROM platforms to form the draft (dCUSP) instrument, which was then used for test-retest validation and item reduction. All domains scored highly for Cronbach's alpha (>0.8), with the exception of GI symptoms. Large Spearman's (>0.76) and Pearson's correlation estimates (>0.83) were obtained for test-retest validity, suggesting that answers were reliable through the time period tested. The estimates of the Spearman's correlation coefficient between each pair of domains ranged from 0.17 to 0.78 and the upper bounds of the corresponding 95% confidence intervals were all smaller than 0.95, suggesting that each domain measures something different. The tests of equality of the mean of scores of the control (n = 25) and patient groups were all significant, suggesting that CUSP successfully discriminated patients suffering from ureteral stones for every domain. CONCLUSION: CUSP is a patient-derived ureteral stone PROM, which can be used to measure ureteral stone disease health outcomes from the patient's point of view.

Prognostic effect of cytoreductive nephrectomy in synchronous metastatic renal cell carcinoma: a comparative study using inverse probability of treatment weighting.

PURPOSE: To test the hypothesis that cytoreductive nephrectomy (CN) improves overall survival (OS) of patients with synchronous metastatic renal cell carcinoma (mRCC), who subsequently receive targeted therapies (TT). METHODS: We identified 261 patients who received TT for synchronous mRCC with or without prior CN. To achieve balance in baseline characteristics between groups, we used the inverse probability of treatment weighting (IPTW) method. We conducted OS analyses, including IPTW-adjusted Kaplan-Meier curves, Cox regression models, interaction term, and landmark and sensitivity analyses. RESULTS: Of the 261 patients, 97 (37.2%) received CN and 164 (62.8%) did not. IPTW-adjusted analyses showed a statistically significant OS benefit for patients treated with CN (HR 0.63, 95% CI 0.46-0.83, P = 0.0015). While there was no statistically significant difference in OS at 3 months (P = 0.97), 6 months (P = 0.67), and 12 months (P = 0.11) from diagnosis, a benefit for the CN group was noted at 18 months (P = 0.005) and 24 months (P = 0.004). On interaction term analyses, the beneficial effect of CN increased with better performance status (P = 0.06), in women (P = 0.03), and in patients with thrombocytosis (P = 0.01). CONCLUSIONS: IPTW-adjusted analysis of our patient cohort suggests that CN improves OS of patients with synchronous mRCC treated with TT. On the whole, the survival difference appears after 12 months. Specific subgroups may particularly benefit from CN, and these subgroups warrant further investigation in prospective trials.

Influence of hospital volume on nephrectomy mortality and complications: a systematic review and meta-analysis stratified by surgical type.

OBJECTIVES: The provision of complex surgery is increasingly centralised to high-volume (HV) specialist hospitals. Evidence to support nephrectomy centralisation however has been inconsistent. We conducted a systematic review and meta-analysis to determine the association between hospital case volumes and perioperative outcomes in radical nephrectomy, partial nephrectomy and nephrectomy with venous thrombectomy. METHODS: Medline, Embase and the Cochrane Library were searched for relevant studies published between 1990 and 2016. Pooled effect estimates for nephrectomy mortality and complications were calculated for each nephrectomy type using the DerSimonian and Laird random-effects model. Sensitivity analyses were performed to examine the effects of heterogeneity on the pooled effect estimates by excluding studies with the heaviest weighting, lowest methodological score and most likely to introduce bias from misclassification of standardised hospital volume. RESULTS: Some 226 372 patients from 16 publications were included in our review and meta-analysis. Considerable between-study heterogeneity was noted and only a few reported volume-outcome relationships specifically in partial nephrectomy or nephrectomy with venous thrombectomy.HV hospitals were correlated with a 26% and 52% reduction in mortality for radical nephrectomy (OR 0.74, 95% CI 0.61 to 0.90, p<0.01) and nephrectomy with venous thrombectomy (OR 0.48, 95% CI 0.29 to 0.81, p<0.01), respectively. In addition, radical nephrectomy in HV hospitals was associated with an 18% reduction in complications (OR 0.82, 95% CI 0.73 to 0.92, p<0.01). No significant volume-outcome relationship in mortality (OR 0.84, 95% CI 0.31 to 2.26, p=0.73) or complications (OR 0.85, 95% CI 0.55 to 1.30, p=0.44) was observed for partial nephrectomy. CONCLUSIONS: Our findings suggest that patients undergoing radical nephrectomy have improved outcomes when treated by HV hospitals. Evidence of this in partial nephrectomy and nephrectomy with venous thrombectomy is however not yet clear and could be secondary to the low number of studies included and the small patient number in our analyses. Further investigation is warranted to establish the full potential of nephrectomy centralisation particularly as existing evidence is of low quality with significant heterogeneity.

Percutaneous nephrolithotomy access by urologist or interventional radiologist: practice and outcomes in the UK.

OBJECTIVE: To compare outcomes of urologist vs interventional radiologist (IR) access during percutaneous nephrolithotomy (PCNL) in the contemporary UK setting. PATIENTS AND METHODS: Data submitted to the British Association of Urological Surgeons PCNL data registry between 2009 and 2015 were analysed according to whether access was obtained by a urologist or an IR. We compared access success, number and type of tracts, and perceived and actual difficulty of access. Postoperative outcomes, including stone-free rates, lengths of hospital stay and complications, including transfusion rates, were also compared. RESULTS: Overall, percutaneous renal access was undertaken by an IR in 3453 of 5211 procedures (66.3%); this rate appeared stable over the entire study period for all categories of stone complexity and in cases where there was predicted or actual difficulty with access. Only 1% of procedures were abandoned because of failed access and this rate was identical in each group. IRs performed more multiple tract access procedures than urologists (6.8 vs 5.1%; P = 0.02), but had similar rates of supracostal punctures (8.2 vs 9.2%; P = 0.23). IRs used ultrasonograhpy more commonly than urologists to guide access (56.6% vs 21.7%, P < 0.001). There were no significant differences in complication rates, lengths of hospital stay or stone-free rates. CONCLUSIONS: Our findings suggest that favourable PCNL outcomes may be expected where access is obtained by either a urologist or an IR, assuming that they have received the appropriate training and that they are skilled and proficient in the procedure.

Hospital Volume Does Not Influence the Safety of Percutaneous Nephrolithotomy in England: A Population-Based Cohort Study.

PURPOSE: This study aims to investigate the relationship between hospital case volume and safety-related outcomes after percutaneous nephrolithotomy (PCNL) within the English National Health Service (NHS). PATIENTS AND METHODS: The study used the Hospital Episode Statistics (HES) database, a routine administrative database, recording information on operations, comorbidity, and outcomes for all NHS hospital admissions in England. Records for all patients undergoing an initial PCNL between April 1, 2006 and March 31, 2012 were extracted. NHS trusts were divided into low-, medium-, and high-volume groups, according to the average annual number of PCNLs performed. We used multiple regression analyses to examine the associations between hospital volume and outcomes incorporating risk adjustment for sex, age, comorbidity, and hospital teaching status. Postoperative outcomes included: Emergency readmission, infection, and hemorrhage. Mean length of stay was also measured. RESULTS: There were 7661 index elective PCNL procedures performed in 163 hospital trusts, between April 2006 and March 2012. There were 2459 patients who underwent PCNL in the 116 units performing fewer than 10 PCNL procedures per year; 2643 patients in the 37 units performing 10 to 19 procedures per year; and 2459 patients in the 9 hospitals performing more than 20 procedures per year. For low-, medium-, and high-volume trusts, there was little variation in the rates of emergency readmission (L 9.7%, M 9.3%, H 8.4%), infection (3.0%, 4.2%, 3.8%), or hemorrhage (1.3%, 1.5%, 1.5%), and there was no statistical evidence that volume was associated with adjusted outcomes. Mean length of stay was slightly shorter in the medium- (5.0 days) and high-volume (5.0) groups compared with the low-volume group (5.3). The effect remained statistically significant after adjusted for confounding. CONCLUSION: Hospital volume was not associated with emergency readmission, infection, or hemorrhage. Length of stay appears to be shorter in higher volume units.

Conservatively managed spontaneous intraperitoneal bladder perforation in a patient with chronic bladder outflow obstruction.

We present the unusual case of a spontaneous intraperitoneal bladder rupture as a first presentation of chronic bladder outflow obstruction secondary to benign prostatic hyperplasia. A contributing factor to diagnostic delay was unfamiliarity with the classical presentation of abdominal pain, abdominal distension and urinary ascites leading to autodialysis represented by an unusually high serum creatinine. A cystogram was performed after a non-contrast computed tomography (CT) scan originally performed to determine the cause of abdominal pain, failed to confirm the diagnosis. The patient's initial acute presentation was successfully managed conservatively with prolonged urinary catheterization.

Hormonal manipulation of lower urinary tract symptoms secondary to benign prostatic obstruction.

Although the etiology of lower urinary tract symptoms (LUTS) is often multifactorial, a significant proportion of men over the age of 50 suffer from benign prostatic obstruction (BPO) secondary to benign prostatic hyperplasia. Prostate, being an androgen responsive organ is dependent on the male sex hormone, testosterone, for growth. Thus, treatment strategies that manipulate the levels of circulating hormones that influence the level of testosterone and/or prostatic growth represent an important potential option for patients suffering with troublesome LUTS due to BPO. Despite this, the only hormonal treatment that is currently used in daily clinical practice is the 5-alpha reductase inhibitor. In this article, we review the current evidence on the use of the 5-alpha reductase inhibitors finasteride and dutasteride. We also discuss new emerging hormonal manipulation strategies for patients with LUTS secondary to BPO.

Percutaneous nephrolithotomy in England: practice and outcomes described in the Hospital Episode Statistics database.

OBJECTIVE: To investigate the postoperative outcomes of percutaneous nephrolithotomy (PCNL) in English National Health Service (NHS) hospitals. PATIENTS AND METHODS: We extracted records from the Hospital Episode Statistics (HES) database for all patients undergoing PCNL between March 2006 and January 2011 in English NHS hospitals. Outcome measures were haemorrhage, infection within the index admission, and rates of emergency readmission and in-hospital mortality within 30 days of surgery. RESULTS: A total of 5750 index PCNL procedures were performed in 165 hospitals. During the index admission, haemorrhage was recorded in 81 patients (1.4%), 192 patients (3.8%) had a urinary tract infection (UTI), 95 patients (1.7%) had fever, and 41 patients (0.7%) had sepsis. There were 595 emergency readmissions in 518 patients (9.0%). Reasons for readmission were varied: 70 (1.2%) with UTI, 15 (0.3%) sepsis, 73 (1.3%) haematuria, 25 (0.4%) haemorrhage, and 25 (0.4%) acute urinary retention. There were 13 (0.2%) in-hospital deaths within 30 days of surgery. CONCLUSIONS: Haemorrhage and infection represent relatively common and potentially severe complications of PCNL. Mortality is extremely rare after PCNL (about one in 400 procedures overall) but almost one in 10 patients have an unplanned hospital readmission within 30 days of surgery. Complications of PCNL may be under-reported in the HES database and need to be corroborated using other data sources.

Percutaneous nephrolithotomy in the United kingdom: results of a prospective data registry.

BACKGROUND: Percutaneous nephrolithotomy (PCNL) is commonly used in the management of large upper renal tract stones. It is highly effective but carries a greater risk of significant morbidity than less invasive treatment options such as ureteroscopy or extracorporeal shock wave lithotripsy. OBJECTIVE: Evaluate the current practice and outcomes of PCNL using a national prospective data registry. DESIGN, SETTING, AND PARTICIPANTS: All surgeons undertaking PCNL in the United Kingdom were invited to submit data to an online registry. MEASUREMENTS: Effectiveness was assessed by stone-free rates and safety according to complications including blood transfusion, fever, and sepsis rates. RESULTS AND LIMITATIONS: Since January 2010, data on 987 patients who had 1028 PCNL procedures were collected. A total of 299 of 1012 procedures (30%) were for staghorn calculi, 299 (30%) for stones >2 cm, 329 (33%) for stones 1-2 cm, and 89 (9%) for stones <1cm. There were no significant differences in rates of failed access or complications according to whether a urologist or radiologist obtained renal access. There was a nonsignificant trend to a higher transfusion rate with balloon dilatation (7 of 222 [3.2%]) compared with serial dilatation (2 of 245 [0.8%]) of the renal tract (p = 0.093). Totally tubeless procedures were not associated with higher complication rates but did lead to a significant reduction in median length of stay (3 d vs 1.5 d; p<0.0001). Intraoperatively, 78% of patients were believed to be stone free, which was confirmed in 68% with postoperative imaging. Blood transfusion was required in 24 of 968 patients (2.5%). The incidence of postoperative fever was 16% and of sepsis was 2.4%. CONCLUSIONS: The PCNL data registry is a unique resource providing vital information on current practice and critical outcome data. Using the registry, endourologists can audit their practice against national outcome data for this benchmark procedure. It will help surgeons counsel patients during consent for this complex endourologic procedure about the possible outcome in their hands.

Mortality in men admitted to hospital with acute urinary retention: database analysis.

OBJECTIVES: To investigate mortality in men admitted to hospital with acute urinary retention and to report on the effects of comorbidity on mortality. DESIGN: Analysis of the hospital episode statistics database linked to the mortality database of the Office for National Statistics. SETTING: NHS hospital trusts in England, 1998-2005. PARTICIPANTS: All men aged over 45 who were admitted to NHS hospitals in England with a first episode of acute urinary retention. MAIN OUTCOME MEASURES: Mortality in the first year after acute urinary retention and standardised mortality ratio against the general population. RESULTS: During the study period, 176 046 men aged over 45 were admitted to hospital with a first episode of acute urinary retention. In 100 067 men with spontaneous acute urinary retention, the one year mortality was 4.1% in men aged 45-54 and 32.8% in those aged 85 and over. In 75 979 men with precipitated acute urinary retention, mortality was 9.5% and 45.4%, respectively. In men with spontaneous acute urinary retention aged 75-84, the most prevalent age group, the one year mortality was 12.5% in men without comorbidity and 28.8% in men with comorbidity. The corresponding figures for men with precipitated acute urinary retention were 18.1% and 40.5%. Compared with the general population, the highest relative increase in mortality was in men aged 45-54 (standardised mortality ratio 10.0 for spontaneous and 23.6 for precipitated acute urinary retention) and the lowest for men 85 and over (1.7 and 2.4, respectively). CONCLUSIONS: Mortality in men admitted to hospital with acute urinary retention is high and increases strongly with age and comorbidity. Patients might benefit from multi-disciplinary care to identify and treat comorbid conditions.