No mutations of FGFR3 in normal urothelium in the vicinity of urothelial carcinoma of the bladder harbouring activating FGFR3 mutations in patients with bladder cancer

Mutations in the fibroblast growth factor receptor 3 (FGFR3) gene causing constitutive oncogenic protein activation have been shown to be frequent in papillary noninvasive bladder tumours and are associated with a low risk of progression and a favourable outcome. FGFR3 alterations have also been found in benign urothelial papilloma and flat urothelial hyperplasia suggesting FGFR3 alterations as an early event in bladder tumorigenesis. To date there is no data available on FGFR3 mutations in normal urothelium from patients with bladder cancer. We therefore analysed 64 samples of histopathological unsuspicious normal urothelium from 38 patients with FGFR3 mutated bladder tumours and 15 samples of urothelium from patients (n = 15) without any urothelial malignancy as a control group. Urothelial cells were microdissected from formalin‐fixed, paraffin‐embedded material. After DNA isolation whole genome amplification was done by I‐PEP‐PCR. FGFR3 mutations were detected using SNaPshot analysis. All samples could successfully be investigated. FGFR3 analyses did not reveal any mutation in the urothelium from neither the control group nor the bladder cancer group. All urothelial samples showed a wildtype sequence for FGFR3. These data suggest that mutations in the FGFR3 gene are not the earliest genetic alterations in bladder carcinogenesis and are associated with a hyperproliferative (hyperplastic) phenotype in the urothelium. Chromosomal alterations like deletions on chromosome 9q or aberrant promoter hypermethylation could play more important roles in early urothelial transformation than mutational FGFR3 activation. © 2009 UICC     

Occupational exposures to polycyclic aromatic hydrocarbons, and respiratory and urinary tract cancers: a quantitative review to 2005.

BACKGROUND: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been reported in several industries, including those of the aluminum production, coal gasification, coke production, iron and steel foundries, coal tar and related products, carbon black and carbon electrodes production. PATIENTS AND METHODS: This paper reviews the results from cohort studies conducted on workers exposed to PAHs in these industries, with a focus on cancers of the respiratory and urinary tract. RESULTS: An excess risk from lung/respiratory cancers was found in most industries, the pooled relative risk (RR) being 2.58 (95% CI 2.28-2.92) for coal gasification, 1.58 (95% CI 1.47-1.69) for coke production, 1.40 (95% CI 1.31-1.49) for iron and steel foundries, 1.51 (95% CI 1.28-1.78) for roofers and 1.30 (95% CI 1.06-1.59) for carbon black production. The evidence for cancers of the bladder and of the urinary system is less consistent, with a significant increased risk only for workers in aluminum production (pooled RR = 1.29, 95% CI 1.12-1.49), coal gasification (pooled RR = 2.39, 95% CI 1.36-4.21), and iron and steel foundries (pooled RR = 1.29, 95% CI 1.06-1.57). CONCLUSIONS: Increased risks from lung and bladder cancers were found in PAH-related occupations. These were modest in most industries, apart from those for coal gasification, and whether they are due at least partially to some bias or confounding remains open to discussion.     

Cancer risk from occupational and environmental exposure to polycyclic aromatic hydrocarbons

Epidemiologic evidence on the relationship between polycyclic aromatic hydrocarbons (PAH) and cancer is reviewed. High occupational exposure to PAHs occurs in several industries and occupations. Covered here are aluminum production, coal gasification, coke production, iron and steel foundries, tar distillation, shale oil extraction, wood impregnation, roofing, road paving, carbon black production, carbon electrode production, chimney sweeping, and calcium carbide production. In addition, workers exposed to diesel engine exhaust in the transport industry and in related occupations are exposed to PAHs and nitro-PAHs. Heavy exposure to PAHs entails a substantial risk of lung, skin, and bladder cancer, which is not likely to be due to other carcinogenic exposures present in the same industries. The lung seems to be the major target organ of PAH carcinogenicity and increased risk is present in most of the industries and occupations listed above. An increased risk of skin cancer follows high dermal exposure. An increase in bladder cancer risk is found mainly in industries with high exposure to PAHs from coal tars and pitches. Increased risks have been reported for other organs, namely the larynx and the kidney; the available evidence, however, is inconclusive. The results of studies addressing environmental PAH exposure are consistent with these conclusions.     

Chromosome 9 deletions are more frequent than FGFR3 mutations in flat urothelial hyperplasias of the bladder

Flat urothelial hyperplasias (FUHs) in patients with papillary bladder tumours frequently show deletions of chromosome 9, suggesting that FUH could be the first neoplastic step in the development of papillary bladder cancer. FGFR3 mutations are frequent in non-invasive papillary tumours with low risk of progression. Our aim was to investigate the frequency of FGFR3 mutations and deletions of chromosomes 9p/q and 8p/q in FUH. Thirty FUH and 9 simultaneous or consecutive tumours were detected by 5-ALA-based photodynamic cystoscopy. DNA was isolated from frozen sections and whole genome amplification was done by I-PEP-PCR, followed by LOH analysis on chromosomes 8p/q and 9p/q. FGFR3 mutations were detected by SNaPshot analysis. LOH analysis on FUH revealed deletions at 9p/q (11/30, 37%) and 8p/q (3/30, 10%). FGFR3 mutations were found in 7/30 FUH (23%). Only 2 FUH showed an FGFR3 mutation without deletions of chromosome 9. In contrast, 6 FUH revealed chromosome 9 deletions but wild type FGFR3 (p = 0.03). These results suggest that chromosome 9 deletions are the earliest genetic alterations in bladder cancer. The detection of FGFR3 mutations in FUH further supports the role of this lesion as precursor of papillary bladder cancer.     

Upregulation of TRAG3 gene in urothelial carcinoma of the bladder

Conventional chemotherapy is commonly used for advanced stages of bladder cancer with modest success and high morbidity. Identifying markers of resistance will allow clinicians to tailor treatment to a specific patient population. T24‐tumorigenic cell line was grown orthotopically in nude mice and monitored using bioluminescence imaging and microcomputed tomography until they developed metastases. Stable sublines were then developed from primary bladder (T24‐P), lung (T24‐L) and bone (T24‐B) tissues. Chromosomal analysis and DNA microarray were used to characterize these sublines. Real‐time quantitative polymerase chain reaction and immunohistochemistry were used for validation. Epigenetic modifiers were used to study gene regulation. The cell viability was quantified with MTT assay. Chromosomal analysis revealed multiple alterations in metastatic cell lines compared to T24‐P. DNA microarray analysis showed that taxol resistance‐associated gene (TRAG) 3 was the most upregulated gene. From real‐time quantitative polymerase chain reaction and immunohistochemistry, TRAG3 was significantly higher in T24‐L and T24‐B than T24‐P. TRAG3 gene expression is likely controlled by DNA methylation but not histone acetylation. Interestingly, T24‐B and T24‐L cells were more resistant than T24‐P to treatment with antimicrotubule agents such as docetaxel, paclitaxel and vinblastine. TRAG3 mRNA expression was higher in 20% of patients with ≤pT2 (n = 10) and 60% of patients with ≥pT3 (n = 20) compared to normal adjacent tissue (p = 0.05). In addition, the median TRAG3 expression was 6.7‐fold higher in ≥pT3 tumors compared to ≤pT2 tumors. Knowing the status of TRAG3 expression could help clinicians tailor treatment to a particular patient population that could benefit from treatment, while allocating patients with resistant tumors to new experimental therapies.     

Phase 2 trial of dovitinib in patients with progressive FGFR3-mutated or FGFR3 wild-type advanced urothelial carcinoma

BackgroundSecond-line treatment options for patients with advanced urothelial carcinoma (UC) are limited. Fibroblast growth factor receptor 3 (FGFR3) is dysregulated in UC by activating mutations or protein overexpression in non-mutant tumours. In this study, the efficacy, pharmacodynamics and safety of dovitinib—a broad-targeted inhibitor of tyrosine kinases, including FGFR3—were evaluated in patients with previously treated advanced UC with and without FGFR3 mutations.MethodsForty-four adults with advanced UC who had progressed after one to three platinum-based and/or combination chemotherapy regimens were classified as having mutant (FGFR3^MUT; n = 12), wild-type (FGFR3^WT; n = 31), or unknown (n = 1) FGFR3 status. Patients received 500 mg dovitinib once daily on a 5-days-on/2-days-off schedule. The primary end-point of this two-stage study was the investigator-assessed overall response rate (ORR).ResultsMost of the patients were men (75%) and over half of the patients were aged ⩾65 years (61%). All patients had received ⩾1 prior antineoplastic therapy for UC. The study was terminated at the end of stage 1, when it was determined by investigator review that the ORR of both the FGFR3^MUT (0%; 95% confidence interval [CI], 0.0–26.5) and FGFR3^WT (3.2%; 95% CI, 0.1–16.7) groups did not meet the criteria to continue to stage 2. The most common grade 3/4 adverse events, suspected to be study-drug related, included thrombocytopenia (9%), fatigue (9%), and asthenia (9%).ConclusionAlthough generally well tolerated, dovitinib has very limited single-agent activity in patients with previously treated advanced UC, regardless of FGFR3 mutation status. clinicaltrials.gov NCT00790426.     

Effects of exposure to polycyclic aromatic hydrocarbons combined with high-risk human papillomavirus infection on cervical intraepithelial neoplasia: A population study in Shanxi Province,China

High-risk human papillomavirus (HR-HPV) infection is a major etiological agent in the progression of cervical intraepithelial neoplasia (CIN) and cervical cancer. Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic pollutants that exist widely in the environment. We hypothesized that PAHs exposure was related to the progression of cervical cancer, and could increase the effect of HR-HPV on CIN. We investigated the effects of PAHs exposure combined with HR-HPV infection on CIN in community population in Shanxi Province, China. A total of 2,285 women were enrolled into the study. HR-HPV genotypes were detected by flow-through hybridization technology. 1-hydroxypyrene (1-OHP) was detected by high-performance liquid chromatography. The top three HR-HPV genotypes were 16, 58 and 52 in turn. With unconditional logistic regression analysis, we found that HR-HPV infection (adjusted odds ratio [aOR] = 4.08, 95% confidence interval [CI]: 3.00–5.54), HPV16 infection (aOR = 4.71, 95% CI: 3.39–6.53), HPV58 infection (aOR = 2.29, 95% CI: 1.41–3.73) and PAHs high exposure (aOR = 2.57, 95% CI: 1.82–3.62) increased the risk of CIN2/3, showing an increasing trend (p < 0.001) with the severity of cervical lesions. Compared to Q1 (<0.06 μmol/molCr) levels of 1-OHP, women with Q4 (>0.11 μmol/molCr) had a higher risk for CIN2/3 (aOR = 7.68, 95% CI: 4.83–12.22). Additionally, we observed that there was a synergic effect between high exposure to PAHs and HR-HPV infection in CIN2/3. Furthermore, the results from the generalized multifactor dimensionality reduction model showed that there were joint interactions of PAHs, HPV16, HPV58 and HPV52 on the risk of CIN2/3. Our study revealed that high exposure to PAHs could increase the risk for CIN, and it posed stronger risk when combined with HR-HPV infection.     

Parental occupation, occupational exposure to solvents and polycyclic aromatic hydrocarbons and risk of childhood brain tumors (Italy, France, Spain)

The role of parental occupational exposure in childhood brain tumorswas investigated in a population-based case-control study grouping 251 casesand 601 controls from three European centers: Milan (Italy), Paris (France),and Valencia (Spain). Parental occupational exposure to solvents andpolycyclic aromatic hydrocarbons (PAH) during the five-year period beforebirth was estimated using a job-exposure matrix developed earlier in the samecountries. Odds ratios (OR) of brain tumors for each occupation andoccupational exposure were estimated by logistic regression, adjusting forchilds age, gender, exposure to tobacco smoke and ionizing radiation,mothers age and years of schooling, and center. The risk of childhood braintumors rose when fathers worked in agriculture (OR = 2.2, 95 percentconfidence interval [CI] = 1.0-4.7) and motor-vehicle-related occupations. Inthe latter group, the risk increased for primitive neuroectodermal tumors inparticular (OR = 2.7, CI = 1.1-6. 6). Astroglial tumors were more frequentamong children of mothers in health services (OR = 2.2, CI = 1.0-4.9).Paternal exposure to PAHs was associated with an increased, but notdose-related, risk of primitive neuroectodermal tumors (OR = 2.0, CI =1.0-4.0), and maternal exposure to solvents at a high level was associatedwith an increased risk of both astroglial (OR = 2.3, CI = 0.9-5.8) andprimitive neuroectodermal tumors (OR = 3.2, CI = 1.0-10.3).     

Occupational exposure to dusts and risk of renal cell carcinoma

Background:

Occupational exposures to dusts have generally been examined in relation to cancers of the respiratory system and have rarely been examined in relation to other cancers, such as renal cell carcinoma (RCC). Although previous epidemiological studies, though few, have shown certain dusts, such as asbestos, to increase renal cancer risk, the potential for other occupational dust exposures to cause kidney damage and/or cancer may exist. We investigated whether asbestos, as well as 20 other occupational dust exposures, were associated with RCC risk in a large European, multi-center, hospital-based renal case–control study.

Methods:

General occupational histories and job-specific questionnaires were reviewed by occupational hygienists for subject-specific information. Odds ratios (ORs) and 95% confidence intervals (95% CIs) between RCC risk and exposures were calculated using unconditional logistic regression.

Results:

Among participants ever exposed to dusts, significant associations were observed for glass fibres (OR: 2.1; 95% CI: 1.1–3.9), mineral wool fibres (OR: 2.5; 95% CI: 1.2–5.1), and brick dust (OR: 1.5; 95% CI: 1.0–2.4). Significant trends were also observed with exposure duration and cumulative exposure. No association between RCC risk and asbestos exposure was observed.

Conclusion:

Results suggest that increased RCC risk may be associated with occupational exposure to specific types of dusts. Additional studies are needed to replicate and extend findings.     

Integrated genetic and epigenetic analysis of bladder cancer reveals an additive diagnostic value of FGFR3 mutations and hypermethylation events

The bladder cancer genome harbors numerous oncogenic mutations and aberrantly methylated gene promoters. The aim of our study was to generate a profile of these alterations and investigate their use as biomarkers in urine sediments for noninvasive detection of bladder cancer. We systematically screened FGFR3, PIK3CA, TP53, HRAS, NRAS and KRAS for mutations and quantitatively assessed the methylation status of APC, ARF, DBC1, INK4A, RARB, RASSF1A, SFRP1, SFRP2, SFRP4, SFRP5 and WIF1 in a prospective series of tumor biopsies (N = 105) and urine samples (N = 113) from 118 bladder tumor patients. We also analyzed urine samples from 33 patients with noncancerous urinary lesions. A total of 95 oncogenic mutations and 189 hypermethylation events were detected in the 105 tumor biopsies. The total panel of markers provided a sensitivity of 93%, whereas mutation and methylation markers alone provided sensitivities of 72% and 70%, respectively. In urine samples, the sensitivity was 70% for all markers, 50% for mutation markers and 52% for methylation markers. FGFR3 mutations occurred more frequently in tumors with no methylation events than in tumors with one or more methylation events (78% vs. 33%; p < 0.0001). FGFR3 mutation in combination with three methylation markers (APC, RASSF1A and SFRP2) provided a sensitivity of 90% in tumors and 62% in urine with 100% specificity. These results suggest an inverse correlation between FGFR3 mutations and hypermethylation events, which may be used to improve noninvasive, DNA‐based detection of bladder cancer.     

复发性膀胱尿路上皮癌中IMP3 和CD44蛋白表达*

目的：评价IMP 3 和CD44蛋白在复发性膀胱癌中表达及二者的相关性。方法：收集2002年1 月至2012年12月经尿道膀胱肿瘤电切术诊断为尿路上皮癌（UC）的病例,其中筛选出6 个月内短期复发组25例和3 年以上较长期首次复发组29例。应用半定量免疫组织化学法检测短期复发组和较长期首次复发组UC病例中IMP 3 和CD44蛋白表达情况。结果：6 个月内UC复发为25例,6 例表达IMP 3,且均为高级别UC。3 年以上较长期首次UC复发为29例,仅有1 例低级别UC表达IMP 3。在短期复发组中IMP 3 阳性率为24%（6/ 25）,表达强度为弱阳性16%（4/ 25）和强阳性8%（2/ 25）,明显高于较长期首次复发组中阳性率3.45%（1/ 29）以及表达强度中的弱阳性3.45%（1/ 29）和强阳性0（0/ 29）。 CD44蛋白表达在两组之间差异无统计学意义。IMP 3 表达与UC复发患者的肿瘤分期、分级呈正相关,而CD44表达与肿瘤的分级呈负相关。IMP 3 表达与CD44表达之间无明显相关性。结论：IMP 3在UC短期复发组中的表达明显高于较长期首次复发组。IMP 3 可作为新的指标,并联合肿瘤病理分期、分级等因素对膀胱UC患者经尿道肿瘤电切术后短期复发的高危性进行预测。     

FGFR3和PIK3CA基因突变影响膀胱癌的预后

背景与目的：成纤维细胞生长因子受体3（fibroblast growth factor receptor 3,FGFR3）和磷脂酰肌醇3-激酶催化亚基ɑ（phosphoinositide 3 kinase catalytic alpha polypeptide,PIK3CA）基因突变与多种肿瘤的发生、发展密切相关。然而,其临床病理意义尚未明确。探讨FGFR3和PIK3CA基因突变对膀胱癌预后的影响。方法：采用Sanger基因测序技术分析于南京中医药大学张家港附属医院行手术治疗的63例膀胱癌患者中FGFR3（外显子7、10、15）和PIK3CA（外显子9、20）基因突变,同时采用免疫组织化学方法检测FGFR3和PIK3CA蛋白水平。分析FGFR3和PIK3CA基因突变与各临床参数的关系,应用Kaplan-Meier方法进行生存分析,通过多因素COX模型回归分析方法对影响膀胱癌预后的因素进行分析。结果：FGFR3基因突变率为17.46%（11/63）,蛋白表达率为33.33%（21/63）,PIK3CA基因突变率为7.93%（5/63）,蛋白表达率为55.56%（35/63）。FGFR3基因突变与年龄、肿瘤是否复发显著相关（P<0.05）,PIK3CA基因突变与各临床参数均无显著相关性（P>0.05）;11例FGFR3 ^mut 中2例PIK3CA ^mut ,52例FGFR3 ^wt 中3例PIK3CA ^mut ,两者比较,差异有统计学意义（χ ² =4.61,P=0.03）。FGFR3基因突变型和野生型的无进展生存期（progression-free survival,PFS）分别为29.13和46.25个月,差异有统计学意义（P=0.021）,而两组的总生存期（overall survival,OS）差异无统计学意义（P>0.05）;PIK3CA基因突变型和野生型比较OS和PFS,差异均无统计学意义（P>0.05）。多参数COX回归分析影响膀胱癌的因素中,FGFR3和PIK3CA基因突变和蛋白表达均不是影响OS的主要因素,病理学分级是影响OS的主要因素,吸烟史和FGFR3基因突变则是影响PFS的主要因素。结论：FGFR3基因突变是膀胱癌预后的不利因素,PIK3CA更易在FGFR3突变的膀胱癌中突变,可能促进FGFR3突变型膀胱癌的恶性行为。     

Relationship between cardiopulmonary mortality and cancer risk and quantitative exposure to polycyclic aromatic hydrocarbons, fluorides, and dust in two prebake aluminum smelters

Objectives

We examined the risk of mortality and cancer incidence with quantitative exposure to benzene-soluble fraction (BSF), benzo(a)pyrene (BaP), fluoride, and inhalable dust in two Australian prebake smelters.

Methods

A total of 4,316 male smelter workers were linked to mortality and cancer incidence registries and followed from 1983 through 2002 (mean follow-up: 15.9 years, maximum: 20 years). Internal comparisons using Poisson regression were undertaken based on quantitative exposure levels.

Results

Smoking-adjusted, monotonic relationships were observed between respiratory cancer and cumulative inhalable dust exposure (trend p = 0.1), cumulative fluoride exposure (p = 0.1), and cumulative BaP exposure (p = 0.2). The exposure–response trends were stronger when examined across the exposed categories (BaP p = 0.1; inhalable dust p = 0.04). A monotonic, but not statistically significant trend was observed between cumulative BaP exposure and stomach cancer (n = 14). Bladder cancer was not associated with BaP or BSF exposure. No other cancer and no mortality outcomes were associated with these smelter exposures.

Conclusions

The carcinogenicity of Söderberg smelter exposures is well established; in these prebake smelters we observed an association between smelter exposures and respiratory cancer, but not bladder cancer. The exploratory finding for stomach cancer needs confirmation. These results are preliminary due to the young cohort and short follow-up time.     

FGFR1和MMP3在食管鳞状细胞癌中的表达及临床意义

目的:观察成纤维细胞成长因子受体1(fibroblast growth factor receptor1,FGFR1)和基质金属蛋白酶3(matrix metalloproteinase 3,MMP3)基因和蛋白在食管鳞癌、癌旁及正常食管组织中的表达情况,探讨它们与食管鳞癌患者临床病理特征之间的关系.方法:采用RT-qPCR、Western blot和免疫组织化学染色检测78例食管鳞癌组织(鳞癌组)、35例食管鳞癌癌旁组织(癌旁组)及35例正常食管组织(正常组)中FGFR1和MMP3 mRNA及蛋白的表达,并分析其与肿瘤临床病理特征之间的关系.结果:FGFR1和MMP3 mRNA在食管鳞癌组表达水平显著高于癌旁组和正常组,差异具有统计学意义(P＜0.05).在癌旁组和正常组表达差异无统计学意义(P＞0.05).FGFR1和MMP3蛋白在食管鳞癌组中的表达率和表达水平明显高于癌旁组和正常组,差异具有统计学意义(P＜0.05).在癌旁组及正常组表达率及表达水平差异均无统计学意义(P＞0.05).FGFR1和MMP3蛋白在食管鳞癌中的表达与患者性别、年龄、肿瘤分化程度无关(P＞0.05),而与肿瘤浸润深度、淋巴结是否转移及TNM分期相关(P＜0.05).食管鳞癌中,FGFR1和MMP3的蛋白表达呈正相关(r=0.303,P＜0.05).结论:FGFR1和MMP3在食管鳞癌中均高表达,两者可能与食管癌的侵袭和转移有关.     

Microcystic urothelial carcinoma of the urinary bladder metastatic to the penis

Metastatic spread of primary bladder cancer to the penis is an extremely rare event. Microcystic urothelial carcinoma is a very rare variant of urothelial carcinoma. Due to its rareness and insufficient clinical follow-up data, the prognosis of microcystic urothelial carcinoma is still not clear. Here in we report a case of a penile metastasis from microcystic urothelial carcinoma of urinary bladder, in a 56year-old man who died 6 months after radical cystoprostatectomy and total penectomy. To the best of our knowledge this is the first case report of microcystic variant of urothelial carcinoma which has metastasized to the penis.     

Occupational exposure to arsenic and risk of nonmelanoma skin cancer in a multinational European study

Occupational studies show a high risk of lung cancer related to arsenic exposure by inhalation; however, only a few studies, and with conflicting results, previously examined a potential link between arsenic exposure at work and skin cancer. The aim of this study is to assess airborne arsenic exposures at the workplace and to quantify associations with nonmelanoma skin cancer (NMSC). The study sample consists of 618 incident cases of NMSC and 527 hospital‐based controls aged 30–79 years from Hungary, Romania and Slovakia. Exposures were evaluated by local experts using occupational histories. Information on host factors and other exposures was collected and used to adjust the associations of interest using multivariable logistic regression. The lifetime prevalence of exposure to work‐related arsenic is 23.9% for cases and 15.5% for controls. No significant association between arsenic exposure in the workplace and NMSC was detected, although an increased adjusted odd ratio was observed for participants with higher cumulative lifetime workplace exposure to arsenic in dust and fumes compared to referents [odds ratios (OR) = 1.94, 95% confidence interval (CI) = 0.76–4.95]. There is evidence for modification of the workplace arsenic–NMSC association by work‐related sunlight exposure in women, with a markedly increased adjusted OR in the presence of workplace sunlight exposure (OR = 10.22, 95% CI = 2.48–42.07). Workplace coexposure to arsenic and sunlight may thus pose an increased risk of NMSC.     

FGFR3 and TP53 gene mutations define two distinct pathways in urothelial cell carcinoma of the bladder

FGFR3 and TP53 mutations are frequent in superficial papillary and invasive disease, respectively. We used denaturing high-performance liquid chromatography and sequencing to screen for FGFR3 and TP53 mutations in 81 newly diagnosed urothelial cell carcinomas. Tumors were classified as follows: 31 pTa, 1 carcinoma in situ, 30 pT1, and 19 pT2-T4. Tumor grades were as follows: 10 G1, 29 G2, and 42 G3. FGFR3 mutations were associated with low-stage (P < 0.0001), low-grade (P < 0.008) tumors, whereas TP53 mutations were associated with high-stage (P < 0.003), high-grade (P < 0.02) tumors. Mutations in these two genes were almost mutually exclusive. Our results suggest that FGFR3 and TP53 mutations define separate pathways at initial diagnosis of urothelial cell carcinoma.