EGFR mutational status in a large series of Caucasian European NSCLC patients: data from daily practice.

BACKGROUND: The prognosis of metastatic non-small cell lung cancer (NSCLC) is still poor. Activating epithelial growth factor receptor (EGFR) mutations are important genetic alterations with dramatic therapeutical implications. Up to now, in contrast to Asian populations only limited data on the prevalence of those mutations are available from patients with Caucasian and especially European ethnicity. METHODS: In this multicentre study, 1201 unselected NSCLC patients from Southern Germany were tested in the daily clinical routine for EGFR mutation status. RESULTS: Activating EGFR mutations were found in 9.8% of all tumours. Mutations in exons 18, 19 and 21 accounted for 4.2%, 61.9% and 33.1% of all mutations, respectively. Non-smokers had a significantly higher rate of EGFR mutations than smokers or ex-smokers (24.4% vs 4.2%; P<0.001). Non-lepidic-non-mucinous adenocarcinomas (G2) accounted for 45.5% of all activating EGFR mutations and 3.5% of all squamous cell carcinomas were tested positive. Thyroid transcription factor 1 protein expression was significantly associated with EGFR mutational status. CONCLUSION: These comprehensive data from clinical routine in Germany add to the knowledge of clinical and histopathological factors associated with EGFR mutational status in NSCLC.

FGFR3 and PIK3CA mutations are involved in the molecular pathogenesis of solar lentigo.

BACKGROUND: Solar lentigines (SL) are frequent benign skin lesions appearing on sun-exposed areas especially in elderly people and therefore represent a hallmark of (photo)aged skin. It has been proposed that SL may subsequently evolve into adenoid seborrhoeic keratosis (SK). However, little is known about the genetic basis of SL. In human SK, FGFR3 and PIK3CA mutations have recently been identified. OBJECTIVES: To analyse SL for potential FGFR3 and PIK3CA mutations. METHODS: We screened 30 SL for FGFR3 mutations using a SNaPshot multiplex assay. For PIK3CA mutations we used direct sequencing of exon 9 and a SNaPshot assay for the H1047R hotspot mutation (exon 20). Because psoralen plus ultraviolet A (PUVA) lentigines show the V600E BRAF hotspot mutation, we additionally investigated this mutation in SL by allele-specific polymerase chain reaction. RESULTS: FGFR3 mutations were detected in five of 30 (17%) SL and PIK3CA mutations in two of 28 (7%) SL. None of 28 SL available for BRAF analysis revealed the V600E mutation. CONCLUSIONS: Our results suggest that FGFR3 and PIK3CA mutations are involved in the pathogenesis of SL. The occurrence of these mutations in both SL and SK suggests a common genetic basis. Our findings furthermore substantiate previous speculations that UV exposure may be a causative factor for FGFR3 and PIK3CA mutations in human skin.

Frequent loss of SFRP1 expression in multiple human solid tumours: association with aberrant promoter methylation in renal cell carcinoma.

Oncogenic wingless-related mouse mammary tumour virus (Wnt) signalling, caused by epigenetic inactivation of specific pathway regulators like the putative tumour suppressor secreted frizzled-related protein 1 (SFRP1), may be causally involved in the carcinogenesis of many human solid tumours including breast, colon and kidney cancer. To evaluate the incidence of SFRP1 deficiency in human tumours, we performed a large-scale SFRP1 expression analysis using immunohistochemistry on a comprehensive tissue microarray (TMA) comprising 3448 tumours from 36 organs. This TMA contained 132 different tumour subtypes as well as 26 different normal tissues. Although tumour precursor stages of, for example kidney, colon, endometrium or adrenal gland still exhibited moderate to abundant SFRP1 expression, this expression was frequently lost in the corresponding genuine tumours. We defined nine novel tumour entities with apparent loss of SFRP1 expression, i.e., cancers of the kidney, stomach, small intestine, pancreas, parathyroid, adrenal gland, gall bladder, endometrium and testis. Renal cell carcinoma (RCC) exhibited the highest frequency of SFRP1 loss (89% on mRNA level; 75% on protein level) and was selected for further analysis to investigate the cause of SFRP1 loss in human tumours. We performed expression, mutation and methylation analysis in RCC and their matching normal kidney tissues. SFRP1 promoter methylation was frequently found in RCC (68%, n=38) and was correlated with loss of SFRP1 mRNA expression (p<0.05). Although loss of heterozygosity was found in 16% of RCC, structural mutations in the coding or promoter region of the SFRP1 gene were not observed. Our results indicate that loss of SFRP1 expression is a very common event in human cancer, arguing for a fundamental role of aberrant Wnt signalling in the development of solid tumours. In RCC, promoter hypermethylation seems to be the predominant mechanism of SFRP1 gene silencing and may contribute to initiation and progression of this disease.

Mdm2-SNP309 polymorphism in prostate cancer: no evidence for association with increased risk or histopathological tumour characteristics.

The search for inherited cancer susceptibility factors is a major focus of epidemiologic cancer studies. Analyses of single-nucleotide polymorphisms (SNP) in a variety of genes revealed a correlation between a specific allele variant and cancer predisposition. Human mouse double-minute 2 protein (Mdm2) is a cellular E3 ligase capable of ubiquitination and degradation of p53. Therefore, Mdm2 is a crucial factor of cell cycle control and cell survival. The Mdm2 promoter SNP309 was shown to increase Mdm2 expression and can, thereby, inhibit the p53 pathway. This SNP was found to be associated with increased risk and early onset of various malignancies. For prostate cancer no studies are reported to date. In a case-control study we determined the distribution of the Mdm2 SNP309 in 145 male subjects with prostate cancer and in 124 male controls without any malignancy using RFLP analysis. Cases and controls showed a similar distribution of the SNP (P=0.299). Genotype distribution showed neither an association with histopathological characteristics of the tumours nor with prognosis. Age at disease onset was also not modified by the SNP. This first study of the Mdm2 SNP309 in prostate cancer patients suggests no correlation between a certain allelic variant and an increased cancer risk.

Exploration of the APC/beta-catenin (WNT) pathway and a histologic classification system for pulmonary artery intimal sarcoma. A study of 18 cases.

APC, a tumor suppressor gene in the Wnt pathway, stabilizes beta-catenin and controls cell growth. Mutation of APC or beta-catenin leads to nuclear accumulation of beta-catenin and transcription of cyclin D1/cyclin A. Pulmonary artery sarcoma (PAS) were studied by morphologic, immunohistochemical, and molecular genetic methods of the Wnt pathway. Eighteen cases were included: mean age 52 years, primary intraluminal location with typical clinical presentation. PAS were classified as epithelioid (n = 4) or malignant fibrous histiocytoma (MFH; spindled/pleomorphic, n = 4), myxofibrosarcoma (n = 8), and one each hemangiopericytoma-like or malignant inflammatory myofibroblastic tumor-like. The tumor cells demonstrated vimentin, focal actins, and rare focal desmin positivity. All but one were grade 2 or 3 by FNCLCC grading. Alteration in chromosome 5q21 (APC) was found in 4/14 PAS by LOH, mostly epithelioid-type; an MFH-type case demonstrated microsatellite instability (MSI) and nuclear beta-catenin. Cyclin D1 was expressed in seven tumors, all myxofibrosarcoma-type. No mutations were detected in APC or beta-catenin. In summary, PAS are predominantly intermediate grade myxofibrosarcoma in middle-aged males, and fatal in two-thirds of patients. Despite myofibroblastic phenotype, APC/beta-catenin pathway changes are rare. Cyclin D1, only expressed in the myxofibrosarcoma-type, is likely transcribed via factors other than beta-catenin.

[German Association for Bladder Cancer Research]. / Deutscher Forschungsverbund Blasenkarzinom e.V.

The "German Association for Bladder Cancer Research" was founded in May 2008 by urologists, scientists, and pathologists. The purpose of this association is to concentrate research activities on a national level, to facilitate collaborations with an interdisciplinary background, and to define standard methodology for a higher quality of scientific results. Additionally, a national database for bladder cancer specimens will be initiated. The website http://www.forschungsverbund-blasenkarzinom.de will provide further information about the German Association for Bladder Cancer Research.

Homozygous G/G variant of SNP309 in the human MDM2 gene is associated with earlier tumor onset in Caucasian female renal cell carcinoma patients.

Human mouse double minute 2 (Mdm2) plays an essential role in the regulation of the tumor suppressor p53. The G/G variant of SNP309 was shown to increase Mdm2 mRNA/protein expression and to be associated with an increased risk and earlier onset of different cancers in Asian populations. However, the frequency and impact of these G/G variants have not been studied in Caucasian renal cell carcinoma (RCC) patients. Therefore, we analyzed an unselected German cohort of 197 consecutive RCC patients and detected the G/G variant in 18 (9.1%) patients, the G/T variant in 116 (58.9%) patients and the T/T variant in 63 (32.0%) patients. Studying the association between age at tumor onset and SNP309 genotypes, no correlation was detected in the entire RCC cohort or among the male RCC patients. However, the female G/G patients (median age 59.5 years) were diagnosed 13.5 years earlier than the T/T females (median age 73 years). When separating all females into two groups at their median age (68 years), 7 and 1 patients with the G/G variant and 9 and 13 patients with the T/T variant were noted in these age groups (P=0.024). To study the age dependency of tumor onset further, a second, age-selected cohort of 205 RCC patients was investigated, which comprised especially young and old patients. Interestingly, the G/G type occurred more often at lower tumor stages and tumor grades compared with higher stages (P=0.039 and 0.004, respectively). In females, the percentage of the G/G variant was only slightly higher in the younger age group, whereas in males, the percentage of the G/G variant was remarkably higher in the younger age group (19.4% vs 8.0%). In summary, female Caucasian RCC patients with the MDM2 SNP309 G/G genotype showed significantly earlier tumor onset than patients with the wild-type T/T genotype.

Behavioral sequelae of perinatal insults and early family adversity at 8 years of age.

OBJECTIVE: This prospective longitudinal study investigated the simultaneous impact of early biological and psychosocial risk factors on behavioral outcome at school age. METHOD: A cohort of 362 children born between 1986 and 1988 with different biological (perinatal insults) and psychosocial risk factors (family adversity) was followed from birth to school age. When their children were aged 8 years, parents of 89.0% of the initial sample completed the Child Behavior Checklist (CBCL). RESULTS: More externalizing as well as internalizing problems were found in children born into adverse family backgrounds, whereas no differences at broad-band syndrome level were apparent between groups with varying obstetric complications. Children with family risk factors had higher scores on 5 of the 8 CBCL scales (including attention, delinquent, and aggressive problems), whereas children with perinatal risk factors had more social and attention problems than children in the nonrisk groups. With one exception, no interactions between risk factors emerged, indicating that perinatal and family risk factors contributed independently to outcome. The differences between risk groups applied irrespective of gender. CONCLUSIONS: The adverse impact of family adversity clearly outweighed the influence of obstetric complications in determining behavioral adjustment at school age.

[Palpebral nystagmus]. / Le nystagmus palpébral.

A case of palpebral nystagmus is reported. Two infarcts were present in the rostral pons, caudal midbrain and in the periaqueductal gray matter between the red nuclei, ventrally to the posterior commissure. The relationships between the palpebral nystagmus and the retraction of the upper lid together with the clinico-pathological significance of the two signs is discussed.

[Prognostic and predictive molecular markers for urologic cancers]. / Prognostische und prädiktive molekulare Marker urologischer Tumoren.

Molecular prognostic factors and genetic alterations as predictive markers for cancer-specific targeted therapies are used today in the clinic for many malignancies. In recent years, many molecular markers for urogenital cancers have also been identified. However, these markers are not clinically used yet. In prostate cancer, novel next-generation sequencing methods revealed a detailed picture of the molecular changes. There is growing evidence that a combination of classical histopathological and validated molecular markers could lead to a more precise estimation of prognosis, thus, resulting in an increasing number of patients with active surveillance as a possible treatment option. In patients with urothelial carcinoma, histopathological factors but also the proliferation of the tumor, mutations in oncogenes leading to an increasing proliferation rate and changes in genes responsible for invasion and metastasis are important. In addition, gene expression profiles which could distinguish aggressive tumors with high risk of metastasis from nonmetastasizing tumors have been recently identified. In the future, this could potentially allow better selection of patients needing systemic perioperative treatment. In renal cell carcinoma, many molecular markers that are associated with metastasis and survival have been identified. Some of these markers were also validated as independent prognostic markers. Selection of patients with primarily organ-confined tumors and increased risk of metastasis for adjuvant systemic therapy could be clinically relevant in the future.

MiR-216a: a link between endothelial dysfunction and autophagy.

Endothelial dysfunction and impaired autophagic activity have a crucial role in aging-related diseases such as cardiovascular dysfunction and atherosclerosis. We have identified miR-216a as a microRNA that is induced during endothelial aging and, according to the computational analysis, among its targets includes two autophagy-related genes, Beclin1 (BECN1) and ATG5. Therefore, we have evaluated the role of miR-216a as a molecular component involved in the loss of autophagic function during endothelial aging. The inverse correlation between miR-216a and autophagic genes was conserved during human umbilical vein endothelial cells (HUVECs) aging and in vivo models of human atherosclerosis and heart failure. Luciferase experiments indicated BECN1, but not ATG5 as a direct target of miR-216a. HUVECs were transfected in order to modulate miR-216a expression and stimulated with 100 µg/ml oxidized low-density lipoprotein (ox-LDL) to induce a stress repairing autophagic process. We found that in young HUVECs, miR-216a overexpression repressed BECN1 and ATG5 expression and the ox-LDL induced autophagy, as evaluated by microtubule-associated protein 1 light chain 3 (LC3B) analysis and cytofluorimetric assay. Moreover, miR-216a stimulated ox-LDL accumulation and monocyte adhesion in HUVECs. Conversely, inhibition of miR-216a in old HUVECs rescued the ability to induce a protective autophagy in response to ox-LDL stimulus. In conclusion, mir-216a controls ox-LDL induced autophagy in HUVECs by regulating intracellular levels of BECN1 and may have a relevant role in the pathogenesis of cardiovascular disorders and atherosclerosis.

Expression of tissue inhibitor of metalloprotease 3 is reduced in ischemic but not neuropathic ulcers from patients with type 2 diabetes mellitus.

Diabetic foot ulceration remains one of the most common and most serious consequences of diabetes. Persistently high levels of matrix metalloproteases (MMPs) contribute to wound chronicity. Our aim was to assess the concentrations of MMPs and tissue inhibitors of metalloproteinases (TIMPs) in neuropathic and ischemic diabetic foot ulcers by analyzing biopsy samples. In this study, biopsies were taken from 35 diabetic foot ulcers of type 2 diabetes mellitus patients and distinguished in neuropathic (n = 14) or ischemic (n = 21). Zymography assay was utilized for the analysis of MMP-2 and MMP-9 activity. TACE activity was evaluated by a specific fluorimetric assay. mRNA levels of MMPs as well as TIMPs were detected using quantitative real-time polymerase chain reaction. The activity of MMP9 and A Disintegrin and A MetalloProtease Domain 17/TNF-Alpha Converting Enzyme (ADAM17/TACE) was significantly increased in ischemic compared to neuropathic biopsies. No differences were detected between both groups for the mRNA levels of MMPs as well as of ADAMs. However, TIMP3 mRNA expression was decreased in ischemic samples. The combination of increased activity of MMP9 and ADAM17/TACE with decreased concentrations of TIMP-3 mRNA expression in ischemic diabetic foot ulcers compared to neuropathic samples suggests that the increased proteolytic environment may represent a causative factor in the ulcer progression. New treatment strategies for healing diabetic foot ulcers could be directed toward increasing levels of TIMP3.

Mutational activation of FGFR3: no involvement in the development of renal cell carcinoma.

BACKGROUND: Somatic point mutations in the fibroblast growth factor receptor 3 (FGFR3) gene have been identified in certain types of urological cancers, especially urothelial carcinoma of the bladder and the renal pelvis, and could be correlated with a favourable outcome. However, comprehensive data on the FGFR3 mutation status in renal cell carcinoma (RCC) are still missing. METHODS: In order to investigate a possible role for FGFR3 mutations in renal cell carcinogenesis, we performed a sequence-based mutational analysis of FGFR3 in 238 primary RCC. The cohort obtained the common RCC subtypes including 101 clear cell, 50 papillary and 68 chromophobe RCC specimens. The analysed regions encompassed all FGFR3 point mutations previously described in epithelial tumours and other noncutaneous epithelial malignancies. RESULTS: No mutations were detected in any renal tumour type examined, and all cases showed wild-type sequence. CONCLUSION: Our results argue against an involvement of mutational activation of FGFR3 in the development of RCC. A recently described cystic renal dysplasia in a patient with thanatophoric dysplasia type 1 due to a germ line FGFR3 mutation might portend to an involvement of mutational FGFR3 activation in renal cyst formation, but this speculation needs further evaluation.

[Plasmacytoid and micropapillary urothelial carcinoma: rare forms of urothelial carcinoma]. / Das plasmazytoide und mikropapilläre Urothelkarzinom : Seltene Varianten eines Urothelkarzinoms.

Plasmacytoid urothelial carcinomas (PUC) along with micropapillary urothelial carcinoma (MPC), small cell cancer, and nested-typed tumors are among the rare variations of urothelial carcinomas. The molecular characterization of PUC and MPC is currently the focus of our research on bladder cancer which we are conducting in cooperation with the Institute of Pathology in Erlangen. PUCs account for approximately 0.9% of all urothelial carcinomas. The diagnosis of these rare variants has acquired increasing importance since this may have prognostic and possibly therapeutic consequences for the patients. By analysis of 32 PUCs we were able to demonstrate the most comprehensive results available to date on the underlying molecular and clinical characteristics of these variants. Micropapillary cancers have already been described in multiple organs. Micropapillary breast cancer represent an individual entity with characteristic genomic aberrations and corresponding clinical and pathological features.

Mcm2 predicts recurrence hazard in stage Ta/T1 bladder cancer more accurately than CK20, Ki67 and histological grade.

Stage Ta/T1 urothelial carcinoma of the bladder (Ta/T1 BC) has a marked tendency to recur. Besides histopathology, markers such as CK20 expression and proliferation index (Ki67) have been shown to predict its clinical course. The replication-licensing factor minichromosome maintenance protein 2 (Mcm2) is a marker of proliferative potential shown to be a promising prognostic marker in various malignancies. The aim of the present study was to evaluate the prognostic value of Mcm2 in comparison to stage, grade, CK20 and Ki67. Initial sporadic Ta/T1 BC (n=71) were evaluated for their expression of CK20, Ki67 and Mcm2 by immunohistochemistry and tissue microarray technology. Prognostic power was analysed by univariate and multivariate Cox regression model for tumour recurrence rate. Median follow-up period was 39 months. A total of 35% patients experienced recurrence. While CK20 was not predictive, grade, Ki67 and Mcm2 were significantly related to recurrence rate in univariate Cox regression model. Only grade (HR 2.37; 95% CI 1.24-4.51; P=0.009) and Mcm2 expression with a cutoff > or = 40% (HR 5.81; 95% CI 2.41-14.00; P<0.001) were independent predictors of recurrence rate in multivariate Cox regression analysis. In addition to grade, expression of Mcm2 is an independent predictor of recurrence in Ta/T1 BC.

Artificial intelligence and bladder cancer arrays.

Non-muscle invasive bladder cancer is a heterogenous disease whose management is dependent upon the risk of progression to muscle invasion. Although the recurrence rate is high, the majority of tumors are indolent and can be managed by endoscopic means alone. The prognosis of muscle invasion is poor and radical treatment is required if cure is to be obtained. Progression risk in non-invasive tumors is hard to determine at tumor diagnosis using current clinicopathological means. To improve the accuracy of progression prediction various biomarkers have been evaluated. To discover novel biomarkers several authors have used gene expression microarrays. Various statistical methods have been described to interpret array data, but to date no biomarkers have entered clinical practice. Here, we describe a new method of microarray analysis using neurofuzzy modeling (NFM), a form of artificial intelligence, and integrate it with artificial neural networks (ANN) to investigate non-muscle invasive bladder cancer array data (n=66 tumors). We develop a predictive panel of 11 genes, from 2800 expressed genes, that can significantly identify tumor progression (average Logrank p = 0.0288) in the analyzed cancers. In comparison, this panel appears superior to those genes chosen using traditional analyses (average Logrank p = 0.3455) and tumor grade (Logrank, p = 0.2475) in this non-muscle invasive cohort. We then analyze panel members in a new non-muscle invasive bladder cancer cohort (n=199) using immunohistochemistry with six commercially available antibodies. The combination of 6 genes (LIG3, TNFRSF6, KRT18, ICAM1, DSG2 and BRCA2) significantly stratifies tumor progression (Logrank p = 0.0096) in the new cohort. We discuss the benefits of the transparent NFM approach with respect to other reported methods.

Genomic aberrations are rare in urothelial neoplasms of patients 19 years or younger.

Urothelial neoplasms in patients 19 years of age or younger are rare, and the data regarding clinical outcome are conflicting. Molecular data are not available. Urothelial tumours from 14 patients aged 4 to 19 years were analysed, including FGFR3 and TP53 mutation screening, comparative genomic hybridization (CGH), UroVysion FISH analysis, polymerase chain reaction for human papillomavirus (HPV), microsatellite analysis using the NIH consensus panel for detection of microsatellite instability (MSI) and six markers for loss of heterozygosity on chromosome arms 9p, 9q, and 17p and immunohistochemistry for TP53, Ki-67, CK20 and the mismatch repair proteins (MRPs) hMSH2, hMLH1, and hMSH6. Based on the 2004 WHO classification, one urothelial papilloma, seven papillary urothelial neoplasms of low malignant potential (PUNLMPs), five low-grade, and one high-grade papillary urothelial carcinoma were included. No multifocal tumours were found and recurrence was seen in only one patient with a urothelial papilloma. All patients were alive with no evidence of disease at a median follow-up of 3.0 years. We found no mutations in FGFR3, deletions of chromosome arms 9p, 9q or 17p, MSI or MRP loss, or HPV positivity in any of the patients. Three cases showed chromosome alterations in CGH analyses, urothelial dedifferentiation with CK20 overexpression, or aneuploidy, and one TP53 mutation with TP53 overexpression was found. Urothelial neoplasms in people younger than 20 years are predominantly low grade and are associated with a favourable clinical outcome. Genetic alterations frequently seen in older adults are extremely rare in young patients. Urothelial neoplasms in children and young adults appear to be biologically distinct and lack genetic instability in most cases.

[Mutation of the FGFR3 oncogene is an independent and favorable prognostic factor for tumor-specific survival in patients with urothelial carcinoma of the upper urinary tract]. / FGFR3-Mutationen in Urothel-Carcinomen des oberen Harntrakts sind mit einer günstigeren Histopathologie und Klinik, aber nicht mit dem Mutator Phänotyp korreliert.

AIMS: Urothelial tumors of the upper urinary tract (UUTT) frequently display microsatellite Instability (MSI) and a distinct pathway of tumorigenesis resembling MMR-deficient colorectal cancers has been recognized for MSI-UUTT. For MSS-UUTT however oncogenic mechanisms as in bladder cancer (BC) are debated. Mutation of the oncogene FGFR3 has been linked to lower stage, lower grade and favourable clinical outcome in BC. The aim of this study was to evaluate FGFR3 mutation in MSI and MSS-UUTT. METHODS: 172 unselected UUTT were screened for MSI using the National Cancer Institute Consensus Panel and additional markers; FGFR3 status was studied using mutation analysis. Histopathological and clinical data were reviewed. RESULTS: Microsatellite status had no impact on histopathological or clinical outcome. 52/99 MSS, 10/22 MSI-low and 25/51 MSI-high UUTT displayed mut. FGFR3 respectively. Overall FGFR3 mutation was associated with favourable stage and grade (p <0.0001 and p <0.002), as 62.1% of mut. vs. 23.5 % of wt. FGFR3 UUTT were stage Ta and T1 and graded G3 in 25.3 % vs. 47.1% respectively. That effect depended on MS-status however, as FGFR3 mutation was related to lower stage (pTa and pT1) in MSS/MSI-L (mut 62.9 % vs. wt 18.7%; p <0.01) only as opposed to MSI-H (mut 60% vs. wt. 50%; p = 0,1) UUTTs and as FGFR3 mut UUTTs tended to display lower grade (G1 and G2) provided stable (mut 74,2 % vs. wt. 44.1%; p <0,01) as opposed to instable microsatellite status (mut 76 % vs. wt. 73 %; p = 0.7). There was no marked relation of MS-status or FGFR3 mutation to sex, age or tobacco-exposure; localization in the renal pelvis (p < 0.01) however was more prevalent in the FGFR3 mut group. As opposed to MSI-status FGFR3 mutation had a favourable impact on survival, as 24.1% vs. 54.2 % cancer related deaths occured in the mutated group (p <0.001); this effect was indendent on stage or MSI-status. Neither MSI- nor FGFR3-status had any influence on subsequent bladder tumors. CONCLUSIONS: FGFR3 mutation is frequent in UUTT and appears to be independent of MS-status; however it is related to significantly favourable histopathological parameters and clinical outcome in MSS cases. Thus our findings might back the notion, that MSS and MSI-UUTTs stem from different oncogenic pathways and that their differing molecular character might have some relevance. Further research is warranted to study the clinical behavior of these tumors and to evaluate a potential role for MS-status and FGFR3 as prognostic tools.