956 resultados para Urinary Bladder Calculi.
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Purpose: Most groups have reported disappointing results with autoaugmentation or detrusor myectomy for low capacity/compliance neuropathic bladders. Failure may be due to an ischemic diverticulum or mucosal shrinkage. We investigated whether a Silimed (R) silicone balloon placed in the bladder after autoaugmentation could prevent these problems, improving surgical results. Materials and Methods: We compared the results of standard bladder autoaugmentation in 12 children (group 1) with those in 10 (group 2) who underwent the same surgery using a bladder conformer. The conformer was a silicone balloon filled with saline that remained in the bladder for 2 weeks. All patients had a neuropathic bladder with poor capacity and compliance, resulting in urinary leakage between catheterizations. Preoperative and postoperative evaluation included a voiding diary, ultrasound, voiding cystourethrogram and urodynamics. Results: In group 1 only 1 patient became dry, 4 had little improvement in continence, 4 remained unchanged and 3 became worse. In group 2, 6 patients (60%) become continent without medication, 2 (20%) become continent with oxybutynin and 2 remained unchanged. Bladder capacity and compliance did not change significantly in group 1. However, in group 2 capacity changed from a mean of 140 to 240 ml and mean +/- SD compliance increased from 15.6 +/- 16.8 to 34.3 +/- 22.8 ml/cm H(2)O (p = 0.02). Conclusions: The inflatable balloon improved our long-term results of bladder auto-augmentation. A larger series may be necessary to confirm procedure efficacy and safety.
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OBJECTIVE To evaluate the correlation between ultrasound-estimated bladder weight (UEBW) in patients with different degrees of bladder outlet obstruction (BOO). METHODS We evaluated 50 consecutive non-neurogenic male patients with lower urinary tract symptoms (LUTS) referred to urodynamic study (UDS). All patients self-answered the International Prostate Score Symptoms (IPSS) questionnaire. After the UDS, the bladder was filled with 150 mL to determine UEBW. Patients with a bladder capacity under 150 mL, a previous history of prostate surgery or pelvic irradiation, an IPSS score <8, a bladder stone or urinary tract infection were excluded. After a pressure-flow study, the Schafer linear passive urethral resistance relation nomogram was plotted to determine the grade of obstruction: Grades I-II/VI were defined as mild obstruction, Grades III-IV/VI as moderate obstruction, and Grades V-VI/VI as severe obstruction. RESULTS The UEBW was 51.7 +/- 26.9, 54.1 +/- 30.0 and 54.8 +/- 28.2 in patients with mild, moderate and severe BOO, respectively (P = 0.130). The UEBW allowed us to define four groups: (i) UEBW < 35 g; (ii) 35 g <= UEBW < 50 g; (iii) 50 g <= UEBW < 70 g; and (4) UEBW >= 70 g. We did not find any differences in age, prostate weight, IPSS, PVR, cystometric bladder capacity, presence of detrusor overactive and degree of obstruction in the aforementioned groups. CONCLUSION Despite the fact that some studies have emphasized the value of UEBW as an efficient non-invasive method for evaluating lower urinary tract obstruction, our study suggests that UEBW does not present any individual correlation with LUTS or objective measurements of BOO.
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Purpose: The bladder is normally impermeable to possible hostile environmental factors and toxic urinary wastes. Any disruption of the permeability barrier would permit the leakage of urine constituents into the underlying cells layers and subsequent inflammation. Protamine sulfate, which increases urothelial permeability, is used in experimental models of cystitis. We examined whether protamine sulfate alone could cause bladder inflammation or if the association of protamine sulfate and urine is needed for this condition. Materials and Methods: Female Wistar rats (Center for the Development of Experimental Models for Medicine and Biology, Federal University of Sao Paulo, Sao Paulo, Brazil) had the bladder catheterized and instilled with protamine sulfate (10 mg) or sterile saline for 30 minutes. To exclude urine other groups of rats underwent bilateral nephrectomy and the same procedure was used. One day after instillation the bladders were removed for histopathology. Edema and vascular congestion were graded from 0-none to 3-severe. Polymorphonuclear and mast cells were counted. The Kruskal-Wallis test was performed for statistical analysis. Results: Intravesical instillation of protamine sulfate in nonnephrectomized rats led to inflammation, in contrast to findings in rats instilled with saline. On the other hand, nephrectomized rats showed no inflammatory changes following the instillation of protamine sulfate or saline. The mast cell count was similar in all groups. Conclusions: Bladder inflammation in this experimental model of urothelial injury was not due to protamine sulfate alone. The association of protamine sulfate and urine was necessary to trigger the inflammatory cascade. Thus, urine indeed has an important role in the development of bladder inflammation in an environment of higher urothelial permeability.
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Bladder cancer (BC) is the fourth most common cancer in the USA. In Brazil, BC represents 3% of the total existing carcinomas in the population and represents the second highest incidence among urological tumors. The majority of bladder cancer cell lines available were derived from Caucasians and established in the seventies or eighties. Thus, neoplasia development in these cells likely occurred in environment conditions vastly different than today. In the present study, we report the establishment and characterization of three Brazilian bladder cancer cell lines (BexBra1, BexBra2, and BexBra4). These cell lines may be helpful for dissecting the genetic and epigenetic aspects that trigger the progression of BC. Moreover, the development of a Brazilian representative of the disease will allow us to investigate the potential inter-racial differences of malignancy-associated phenotypes in bladder cancer.
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Purpose: We tested whether the combination of 4 established cell cycle regulators (p53, pRB, p21 and p27) could improve the ability to predict clinical outcomes in a large multi-institutional collaboration of patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder. We also assessed whether the combination of molecular markers is superior to any individual biomarker. Materials and Methods: The study comprised 692 patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder treated with radical cystectomy and bilateral lymphadenectomy (median followup 5.3 years). Scoring was performed using advanced cell imaging and color detection software. The base model incorporated patient age, gender, stage, grade, lymphovascular invasion, number of lymph nodes removed, number of positive lymph nodes, concomitant carcinoma in situ and adjuvant chemotherapy. Results: Individual molecular markers did not improve the predictive accuracy for disease recurrence and cancer specific mortality. Combination of all 4 molecular markers into number of altered molecular markers resulted in significantly 1 higher predictive accuracy than any single biomarker (p < 0.001.). Moreover addition of number of altered molecular markers to the base model significantly improved the predictive accuracy for disease recurrence (3.9%, p < 0.001) and cancer specific mortality (4.3%, p < 0.001). Addition of number of altered molecular markers retained statistical significance for improving the prediction of clinical outcomes in the subgroup of patients with pT3N0 (280), pT4N0 (83) and pTany Npositive (329) disease (p < 0.001). Conclusions: While the status of individual molecular markers does not add sufficient value to outcome prediction in patients with advanced urothelial carcinoma of the bladder, combinations of molecular markers may improve molecular staging, prognostication and possibly prediction of response to therapy.
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Purpose: We examined the development of urological abnormalities in a group of pediatric renal transplant recipients. Materials and Methods: We reviewed 211 patients younger than 19 years who underwent 226 renal transplants. Three groups of patients were studied-136 children with end stage renal disease due to a nonurological cause (group 1), 56 children with a urological disorder but with an adequate bladder (group 2a) and 19 children with lower urinary tract dysfunction and/or inadequate bladder drainage (group 2b). A total of 15 children in group 2b underwent bladder augmentation (ureterocystoplasty in 6, enterocystoplasty in 9), 2 underwent continent urinary diversion, 1 underwent autoaugmentation and 1 underwent a Mitrofanoff procedure at the bladder for easier drainage. Kidney transplantation was performed in the classic manner by extraperitoneal access, and whenever possible the ureter was reimplanted using an antireflux procedure. Results: At a mean followup of 75 months 13 children had died, 59 grafts were lost and 15 children had received a second transplant. Two patients in group 2a required a complementary urological procedure to preserve renal function (1 enterocystoplasty, 1 vesicostomy). A total of 12 major surgical complications occurred in 226 kidney transplants (5.3%), with a similar incidence in all groups. The overall graft survival at 5 years was 75%, 74% and 84%, respectively, in groups 1, 2a and 2b. Conclusions: With individualized treatment children with severely inferior lower urinary tract function may undergo renal transplantation with a safe and adequate outcome.
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The morphologic appearance and clinical behavior of the human urinary bladder papillary transitional cell carcinoma (TCC) probably result from a complex interaction between carcinogenic insults and host resistance during the patient`s life. While the main recognized risk factors are of environmental origin (e.g. smoking), relatively little information exists about the susceptibility to TCC development. The human leukocyte antigen G (HLA-G) molecule plays an important role in immune response regulation and has been implicated in the inhibition of the cytolytic function of natural killer and cytotoxic T cells. Several lines of evidence indicate that HLA-G polymorphisms influence the expression level and production of different HLA-G isoforms. The aim of this study was to explore a possible influence of the HLA-G polymorphism on the susceptibility to urinary bladder TCC development and progression in smokers and nonsmokers Brazilian subjects. The HLA-G locus was found to be associated with susceptibility to TCC development and progression. The G*0104 allelic group (specially the G*010404 allele) and the G*0103 allele were associated with a tobacco-dependent influence on TCC development. The G*0104 group was associated with progression to high-grade tumors, irrespective of smoking habit, while the G*0103 allele was associated to high-grade tumor only in smoking patients. Our results are an evidence that the HLA-G locus itself, or as part of an extended haplotype encompassing this chromosome region (particularly the HLA-A given the high linkage disequilibrium observed between them in this data series), may be associated with TCC susceptibility and tumor progression, suggesting a tobacco-dependent influence of these polymorphisms.
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Currently, the combination of cisplatin and gemcitabine is considered a standard chemotherapeutic protocol for bladder cancer. However, the mechanism by which these drugs act on tumor cells is not completely understood. The aim of the present study was to investigate the effects of these two antineoplastic drugs on the apoptotic index and cell cycle kinetics of urinary bladder transitional carcinoma cell lines with wild-type or mutant TP53 (RT4: wild type for TP53; 5637 and T24: mutated TP53). Cytotoxicity, cell survival assays, clonogenic survival assays and flow cytometric analyses for cell cycle kinetics and apoptosis detection were performed with three cell lines treated with different concentrations of cisplatin and gemcitabine. G(1) cell cycle arrest was observed in the three cell lines after treatment with gemcitabine and gemcitabine plus cisplatin. A significant increase in cell death was also detected in all cell lines treated with cisplatin or gemcitabine. Lower survival rates occurred with the combined drug protocol independent of TP53 status. TP53-wild type cells (RT4) were more sensitive to apoptosis than were mutated TP53 cells when treated with cisplatin or gemcitabine. Concurrent treatment with cisplatin and gemcitabine was more effective on transitional carcinoma cell lines than either drug alone; the drug combination led to a decreased cell survival that was independent of TP53 status. Therefore, the synergy between low concentrations of cisplatin and gemcitabine may have clinical relevance, as high concentrations of each individual drug are toxic to whole organisms.
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Despite the wide acceptance that glycans are centrally implicated in immunity, exactly how they contribute to the tilt immune response remains poorly defined. In this study, we sought to evaluate the impact of the malignant phenotype-associated glycan, sialyl-Tn (STn) in the function of the key orchestrators of the immune response, the dendritic cells (DCs). In high grade bladder cancer tissue, the STn antigen is significantly overexpressed and correlated with the increased expression of ST6GALNAC1 sialyltransferase. Bladder cancer tissue presenting elevated expression of ST6GALNAC1 showed a correlation with increased expression of CD1a, a marker for bladder immature DCs and showed concomitant low levels of Th1-inducing cytokines IL-12 and TNF-α. In vitro, human DCs co-incubated with STn+ bladder cancer cells, had an immature phenotype (MHC-IIlow, CD80low and CD86low) and were unresponsive to further maturation stimuli. When contacting with STn+ cancer cells, DCs expressed significantly less IL-12 and TNF-α. Consistent with a tolerogenic DC profile, T cells that were primed by DCs pulsed with antigens derived from STn+ cancer cells were not activated and showed a FoxP3high IFN-γlow phenotype. Blockade of STn antigens and of STn+ glycoprotein, CD44 and MUC1, in STn+ cancer cells was able to lower the induction of tolerance and DCs become more mature. Overall, our data suggest that STn-expressing cancer cells impair DC maturation and endow DCs with a tolerogenic function, limiting their capacity to trigger protective anti-tumour T cell responses. STn antigens and, in particular, STn+ glycoproteins are potential targets for circumventing tumour-induced tolerogenic mechanisms.
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RESUMO: Introdução. O cancro de bexiga é uma patologia comum que representa o 6° e o 5° cancro mais incidente em Portugal e na Itália, respetivamente. Em mais de metade dos casos ocorre reincidência durante o primeiro ano, requerendo acompanhamento clínico ao longo da vida. A instilação intravesical de Bacillus Calmette-Guérin (BCG) (uma estirpe atenuada do Mycobacterium bovis) representa uma imunoterapia eficaz no combate ao cancro de bexiga, no entanto, muitos aspetos da interação de BCG com as células tumorais bem como com as células do sistema imunitário permanecem por desvendar. As células tumorais de bexiga expressam frequentemente as formas sialiladas dos antigénios de Thomsen-Friedenreich (TF), i.e., sialil-T (sT) e sialil-Tn (sTn). Contudo ainda se desconhece o significado da sua expressão na malignidade tumoral e se afeta a eficácia da terapêutica BCG. Objetivo do estudo. Investigar o papel dos antigénios sT e sTn no fenótipo maligno de células de cancro de bexiga bem como na resposta mediada pelo sistema imunitário à terapia com BCG. Metodologia. Para tal, foram utilizadas as linhas celulares de cancro da bexiga HT1376 e MCR, geneticamente modificadas por transdução com vetores codificantes para as sialiltransferases ST3GAL1 ou ST6GALNAC1, de forma a expressar homogeneamente os antigénios sT ou sTn respetivamente. Estes modelos celulares foram estudados após confronto com BCG. O nível de BCG internalizado foi avaliado por citometria de fluxo. O perfil global de expressão genética dos modelos celulares antes e após incubação com BCG foi analisado pela tecnologia de microarray. O perfil de citocinas secretadas pelos modelos celulares após incubação com BCG, bem como de macrófagos estimulados pelo secretoma de células de cancro de bexiga que por sua vez foram estimuladas previamente por BCG, foi estudado pelo sistema multiplex de “imuno-esferas”. Resultados. A análise do transcritoma dos modelos celulares revelou que grupos de genes envolvidos em funções específicas foram modulados em paralelo nos dois modelos celulares, após transdução, independentemente da sialiltransferase expressa. Ou seja, em células que expressavam a sialiltransferase ST3GAL1 ou ST6GALNAC1, os genes envolvidos na regulação da segregação cromossómica e na reparação do DNA foram consistentemente regulados negativamente. Genes descritos na literatura como marcadores para o cancro de bexiga foram também modulados. A incubação com BCG resultou numa tendência ao aumento da expressão de genes relevantes na preservação e estabilidade genómica e menor malignidade, no entanto, apenas em células que expressavam sT ou sTn. Entre as dez citocinas testadas, apenas a IL-6 e IL-8 foram expressas pelas linhas celulares de cancro da bexiga, com indução destas após estimulação com BCG, e principalmente em células que expressavam ST3GAL1 ou ST6GALNAC1. Em macrófagos, citocinas inflamatórias, tais como IL-1β, IL-6 e TNFα, e a citocina anti-inflamatória IL-10, foram induzidas apenas pelo secretoma de células de cancro da bexiga confrontadas com BCG, com maior relevância quando estas expressavam ST3GAL1 ou ST6GALNAC1, prevendo a estimulação de macrófagos semelhantes aos de tipo M1 e uma melhor resposta à terapia com BCG. Conclusões. O efeito geral da expressão destas sialiltransferases e dos produtos enzimáticos sT ou sTn nas células de cancro de bexiga conduz a um fenótipo de maior malignidade. Contudo, a maior avidez de estas na produção de citocinas inflamatórias após confronto com BCG, bem como a maior capacidade de estimulação de macrófagos, predirá uma resposta à terapia com BCG mais eficaz em tumores que expressem os antigénios de TF sialilados. Tais conclusões são totalmente concordantes com os nossos mais recentes dados clínicos obtidos em colaboração, que mostram que em doentes com cancro de bexiga que expressam sTn respondem melhor a terapia BCG. ----------ABSTRACT: Background. Bladder cancer is a common malignancy representing the 6th and the 5th most incident cancer in Portugal and in Italy, respectively. More than half of the cases relapse within one year, requiring though a lifelong follow-up. Intravesical instillation of Bacillus Calmette-Guérin (BCG) (an attenuated strain of Mycobacterium bovis) represents an effective immunotherapy of bladder cancer, although many aspects of the interaction of BCG with cancer cells and host immune cells remain obscure. Bladder cancer cells often express the sialylated forms of the Thomsen-Friedenreich (TF), i.e., sialil-T (sT) e sialil-Tn (sTn). However, it’s still unknown the sense of such expression in tumour malignancy and in the BCG therapy efficacy. Aim of the study. To investigate the role of the sT and sTn antigens on the malignant phenotype of bladder cancer cells and the immune mediated response to BCG therapy. Experimental. We have utilized populations of the bladder cancer cell lines HT1376 and MCR, genetically modified by transduction with the sialyltransferases ST3GAL1 or ST6GALNAC1 to express homogeneously sT or sTn antigens. The level of BCG internalized was assessed by flow cytometry. The whole gene expression profile of BCG-challenged or unchallenged bladder cancer cell lines was studied by microarray technology. The profile of cytokines secreted by BCG-challenged bladder cancer cells and that of macrophages challenged by the secretome of BCG-challenged bladder cancer cells was studied by multiplex immune-beads assay. Results. Transcriptome analysis of the sialyltransferase-transduced cells revealed that groups of genes involved in specific functions were regulated in parallel in the two cell lines, regardless the sialyltransferase expressed. Namely, in sialyltransferase-expressing cells, genes involved in the proper chromosomal segregation and in the DNA repair were consistently down-regulated, while genes reported in literature as markers for bladder cancer were modulated. BCG-challenging induced a tendency to up-regulation of the genes preserving genomic stability and reducing malignancy, but only in cells expressing either sT or sTn. Among the ten cytokines tested, only IL-6 and IL-8 were expressed by bladder cancer cell lines and up-regulated by BCG-challenging, mainly in sialyltransferases-expressing cells. In macrophages, inflammatory cytokines, such as IL-1β, IL-6 and TNFα, and the antinflammatory IL-10 were induced only by the secretome of BCG-challenged bladder cancer cells, particularly when expressing either sialyltransferase, predicting the stimulation of M1-like macrophages and a better response to BCG therapy. Conclusions. The general effect of the expression of the two sialyltransferases and their products in the bladder cancer cells is toward a more malignant phenotype. However, the stronger ability of sialyltransferase expressing cells to produce inflammatory cytokines upon BCG-challenging and to stimulate macrophages predicts a more effective response to BCG in tumours expressing the sialylated TF antigens. This is fully consistent with our recent clinical data obtained in collaboration, showing that patients with bladder cancer expressing sTn respond better to BCG therapy.
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Mega-organs, primarily in the digestive tract, are well known to occur in chronic Chagas disease. Acute experimental infection with Trypanosoma cruzi results in parasitism of a wide range of cells, tissues, and organs, including the urinary bladder. Infection of BALB/c mice with 100,000 bloodstream forms of the Y strain of T. cruzi induced acute infection with intense parasitism of all layers of the urinary bladder. Parasites were found in the mucosa, lamina propria, muscular, adventitial connective, and fat tissue. Desquamate epithelial cells with amastigotes in the bladder lumen were also found. After 60 days of infection, mice inoculated with 50 bloodstream forms developed dilated, thin-walled bladders that had inflammatory infiltrates and foci of fibrosis replacing areas of damaged muscular layer. These lesions result from direct damage to the muscle fibers by the T. cruzi, leading to myosites, muscle damage, and scarring. Direct damage of paraganglia cells secondary to parasitism, leading to dilatation, damage of muscle fibers, and scarring with replacement of muscular tissue with connective tissue, should also be considered as a cause of functional disturbance of the urinary bladder.
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This study investigates in vitro growth of human urinary tract smooth muscle cells under static conditions and mechanical stimulation. The cells were cultured on collagen type I- and laminin-coated silicon membranes. Using a Flexcell device for mechanical stimulation, a cyclic strain of 0-20% was applied in a strain-stress-time model (stretch, 104 min relaxation, 15 s), imitating physiological bladder filling and voiding. Cell proliferation and alpha-actin, calponin, and caldesmon phenotype marker expression were analyzed. Nonstretched cells showed significant better growth on laminin during the first 8 days, thereafter becoming comparable to cells grown on collagen type I. Cyclic strain significantly reduced cell growth on both surfaces; however, better growth was observed on laminin. Neither the type of surface nor mechanical stimulation influenced the expression pattern of phenotype markers; alpha-actin was predominantly expressed. Coating with the extracellular matrix protein laminin improved in vitro growth of human urinary tract smooth muscle cells.
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Comparative ultrastructural observations are presented of the distended bladder of a hibernating dormouse (Muscardinus avellanarius) and a relaxed organ taken from an active animal. The distended bladder of the hibernating animal has an extremely thin wall lined with a three-layer urothelium. An osmiophilic coat lines the luminal surface of the urothelium in the hibernating animal, but it is very thin indeed in the specimen from the active dormouse. In the urothelium of the distended bladder, a larger number of fusiform vesicles (FVs, typical structures of the urothelium with asymmetric unit membrane) is found. On the contrary, lysosomes, multivesicular bodies, and interdigitation of plasma membrane between adjacent cells are all more frequent in the relaxed bladder of the active dormouse. Results suggest that hibernating animals can be a useful model for investigating the biology of epithelial cells in the mammalian bladder.
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Aims: To evaluate whether ki-67 labelling index (LI) has independent prognostic value for survival of patients with bladder urothelial tumours graded according to the 2004 World Health Organisation classification. Methods: Ki-67 LI was evaluated in 164 cases using the grid counting method. Non-invasive (stage Ta) tumours were: papilloma (n = 5), papillary urothelial neoplasia of low malignant potential (PUNLMP; n = 26), and low (LG; n = 34) or high grade (HG; n = 15) papillary urothelial carcinoma. Early invasive (stage T1) tumours were: LG (n = 58) and HG (n = 26) carcinoma. Statistical analysis included Fisher and x2 tests, and mean comparisons by ANOVA and t test. Univariate and multivariate survival analyses were performed according to the Kaplan–Meier method with log rank test and Cox’s proportional hazard method. Results: Mean ki-67 LI increased from papilloma to PUNLMP, LG, and HG in stage Ta (p,0.0001) and from LG to HG in stage T1 (p = 0.013) tumours. High tumour proliferation (.13%) was related to greater tumour size (p = 0.036), recurrence (p = 0.036), progression (p = 0.035), survival (p = 0.054), and high p53 accumulation (p = 0.015). Ki-67 LI and tumour size were independent predictors of disease free survival (DFS), but only ki-67 LI was related to progression free survival (PFS). Cancer specific overall survival (OS) was related to ki-67 LI, tumour size, and p27kip1 downregulation. Ki-67 LI was the main independent predictor of DFS (p = 0.0005), PFS (p = 0.0162), and cancer specific OS (p = 00195). Conclusion: Tumour proliferation measured by Ki-67 LI is related to tumour recurrence, stage progression, and is an independent predictor of DFS, PFS, and cancer specific OS in TaT1 bladder urothelial cell carcinoma.
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BACKGROUND Spain shows the highest bladder cancer incidence rates in men among European countries. The most important risk factors are tobacco smoking and occupational exposure to a range of different chemical substances, such as aromatic amines. METHODS This paper describes the municipal distribution of bladder cancer mortality and attempts to "adjust" this spatial pattern for the prevalence of smokers, using the autoregressive spatial model proposed by Besag, York and Molliè, with relative risk of lung cancer mortality as a surrogate. RESULTS It has been possible to compile and ascertain the posterior distribution of relative risk for bladder cancer adjusted for lung cancer mortality, on the basis of a single Bayesian spatial model covering all of Spain's 8077 towns. Maps were plotted depicting smoothed relative risk (RR) estimates, and the distribution of the posterior probability of RR>1 by sex. Towns that registered the highest relative risks for both sexes were mostly located in the Provinces of Cadiz, Seville, Huelva, Barcelona and Almería. The highest-risk area in Barcelona Province corresponded to very specific municipal areas in the Bages district, e.g., Suría, Sallent, Balsareny, Manresa and Cardona. CONCLUSION Mining/industrial pollution and the risk entailed in certain occupational exposures could in part be dictating the pattern of municipal bladder cancer mortality in Spain. Population exposure to arsenic is a matter that calls for attention. It would be of great interest if the relationship between the chemical quality of drinking water and the frequency of bladder cancer could be studied.