Isolating the effect of confounding from the observed survival benefit of screening participants - a methodological approach illustrated by data from the German mammography screening programme.

BACKGROUND: Mammography screening programmes (MSP) aim to reduce breast cancer mortality by shifting diagnoses to earlier stages. However, it is difficult to evaluate the effectiveness of current MSP because analyses can only rely on observational data, comparing women who participate in screening with women who do not. These comparisons are subject to several biases: one of the most important is self-selection into the MSP, which introduces confounding and is difficult to control for. Here, we propose an approach to quantify confounding based on breast cancer survival analyses using readily available routine data sources. METHODS: Using data from the Cancer Registry of North Rhine-Westphalia, Germany, we estimate the relative contribution of confounding to the observed survival benefit of participants of the German MSP. This is accomplished by comparing non-participants, participants with screen-detected and participants with interval breast cancers for the endpoints "death from breast cancer" and "death from all causes other than breast cancer" - the latter being assumed to be unrelated to any MSP effect. By using different contrasts, we eliminate the effects of stage shift, lead and length time bias. The association of breast cancer detection mode with survival is analysed using Cox models in 68,230 women, aged 50-69 years, with breast cancer diagnosed in 2006-2014 and followed up until 2018. RESULTS: The hazard of dying from breast cancer was lower in participants with screen-detected cancer than in non-participants (HR = 0.21, 95% CI: 0.20-0.22), but biased by lead and length time bias, and confounding. When comparing participants with interval cancers and non-participants, the survival advantage was considerably smaller (HR = 0.62, 95% CI: 0.58-0.66), due to the elimination of stage shift and lead time bias. Finally, considering only mortality from causes other than breast cancer in the latter comparison, length time bias was minimised, but a survival advantage was still present (HR = 0.63, 95% CI: 0.56-0.70), which we attribute to confounding. CONCLUSIONS: This study shows that, in addition to stage shift, lead and length time bias, confounding is an essential component when comparing the survival of MSP participants and non-participants. We further show that the confounding effect can be quantified without explicit knowledge of potential confounders by using a negative control outcome.

Sex-Specific Causes and Consequences of White Matter Damage in a Middle-Aged Cohort.

Objective: To evaluate potential sex-specific effects of multiple cardiovascular risk factors on white matter pathology in normal aging men and women, as well as potential sex-differences in the association of white matter pathology and cognitive functions. Methods: We analyzed cross-sectional data of 581 participants (median age: 53 years, 54% women) of the population-based cohort of the BiDirect Study who completed clinical examinations, five neuropsychological tests, and an 3T MRI examination. White matter pathology was determined by the extent of white matter hyperintensities (WMH) on FLAIR images as well as the magnitude of global fractional anisotropy (FA) based on diffusion tensor imaging. Main effects, interaction as well as sex-stratified generalized linear regression models were used to evaluate the moderating effect of sex on the association of hypertension, diabetes mellitus, smoking, and obesity with WMH and FA, respectively. Associations of imaging markers with cognitive test results were determined with linear regression models. Results: Hypertension showed stronger associations with more extensive WMH and less FA in women compared to men. Current smoking was associated with more severe WMH in women only. Adjusted for age and education, WMH were not significantly associated with cognitive tests, but higher FA was associated with better performance in motor function in both sexes and with executive functions in men, even after adjustment for cardiovascular risk factors. Conclusion: We observed a stronger association of hypertension and smoking with white matter damage in women, suggesting a higher susceptibility for vascular pathology in women. However, there was no association of WMH with cognition, and FA was associated with executive function tests only in men, suggesting a higher cognitive reserve in women.

The Relative Importance of Vascular Risk Factors on Early Cognitive Aging Varies Only Slightly Between Men and Women.

Objective: To investigate the sex-specific course and impact of vascular risk factors on cognitive aging in a rather young and healthy community-dwelling cohort. Methods: We used data from a population-based cohort study, collected three times during 6 years, comprising 1,911 examinations from 798 participants aged 35-66 years at baseline. Cognitive performance on the Color-Word-Interference-Test, the Trail Making Tests (TMT) A&B, the Word Fluency Test, a 12-item word list, the Purdue Pegboard Test and a principal component global score were used as outcomes in linear mixed models. We evaluated (1) sex differences in cognitive trajectories, (2) the mediating role of hypertension, diabetes, smoking and obesity [body mass index (BMI) > 30] on sex differences and (3) in sex-stratified analyses, potential sex-specific effects of these risk factors on cognition. Results: For all cognitive tests, we observed cognitive decline with age. Rates of decline slightly differed across sexes, showing a later but steeper decline for women in tests of memory (word list) and word fluency, but a steeper decline for men in tests of psychomotor speed and mental set shifting (TMT A&B) in older age. Women generally scored better on cognitive tests, but the slightly higher prevalence of classical vascular risks factors in men in our cohort could not explain these sex differences. Sex-stratified analyses revealed a generally small, concordantly negative, but quantitatively slightly different impact of diabetes, smoking and obesity on cognitive functions but mixed effects for arterial hypertension, depending on the blood pressure values, the treatment status and the duration of arterial hypertension. Conclusion: Cognitive sex differences in this rather young and healthy cohort could not be explained by a differing prevalence of vascular risks factors across sexes. The association of cardiovascular risk factors with cognition, however, slightly differed between men and women, whereby effects were generally small. Whereas longtime diabetes, obesity and smoking had a sex-specific, but concordantly negative impact on psychomotor speed, executive and motor functions, we found some opposing effects for arterial hypertension. Our results can help to identify sex-specific susceptibilities to modifiable risk factors, to attract attention to potential information bias and to stimulate further research into alternative causes and mechanism of sex differences in cognitive aging.

TGFBI Protein Is Increased in the Urine of Patients with High-Grade Urothelial Carcinomas, and Promotes Cell Proliferation and Migration.

Here, we discovered TGFBI as a new urinary biomarker for muscle invasive and high-grade urothelial carcinoma (UC). After biomarker identification using antibody arrays, results were verified in urine samples from a study population consisting of 303 patients with UC, and 128 urological and 58 population controls. The analyses of possible modifying factors (age, sex, smoking status, urinary leukocytes and erythrocytes, and history of UC) were calculated by multiple logistic regression. Additionally, we performed knockdown experiments with TGFBI siRNA in bladder cancer cells and investigated the effects on proliferation and migration by wound closure assays and BrdU cell cycle analysis. TGFBI concentrations in urine are generally increased in patients with UC when compared to urological and population controls (1321.0 versus 701.3 and 475.6 pg/mg creatinine, respectively). However, significantly increased TGFBI was predominantly found in muscle invasive (14,411.7 pg/mg creatinine), high-grade (8190.7 pg/mg) and de novo UC (1856.7 pg/mg; all p < 0.0001). Knockdown experiments in vitro led to a significant decline of cell proliferation and migration. In summary, our results suggest a critical role of TGFBI in UC tumorigenesis and particularly in high-risk UC patients with poor prognosis and an elevated risk of progression on the molecular level.

Noninvasive diagnosis of urothelial cancer in urine using DNA hypermethylation signatures-Gender matters.

Urothelial cancer (UCa) is the most predominant cancer of the urinary tract and noninvasive diagnosis using hypermethylation signatures in urinary cells is promising. Here, we assess gender differences in a newly identified set of methylation biomarkers. UCa-associated hypermethylated sites were identified in urine of a male screening cohort (n = 24) applying Infinium-450K-methylation arrays and verified in two separate mixed-gender study groups (n = 617 in total) using mass spectrometry as an independent technique. Additionally, tissue samples (n = 56) of mixed-gender UCa and urological controls (UCt) were analyzed. The hypermethylation signature of UCa in urine was specific and sensitive across all stages and grades of UCa and independent on hematuria. Individual CpG sensitivities reached up to 81.3% at 95% specificity. Albeit similar methylation differences in tissue of both genders, differences were less pronounced in urine from women, most likely due to the frequent presence of squamous epithelial cells and leukocytes. Increased repression of methylation levels was observed at leukocyte counts ≥500/µl urine which was apparent in 30% of female and 7% of male UCa cases, further confirming the significance of the relative amounts of cancerous and noncancerous cells in urine. Our study shows that gender difference is a most relevant issue when evaluating the performance of urinary biomarkers in cancer diagnostics. In case of UCa, the clinical benefits of methylation signatures to male patients may outweigh those in females due to the general composition of women's urine. Accordingly, these markers offer a diagnostic option specifically in males to decrease the number of invasive cystoscopies.

Soluble chemokine (C-X-C motif) ligand 16 (CXCL16) in urine as a novel biomarker candidate to identify high grade and muscle invasive urothelial carcinomas.

Information on biomarkers of urothelial carcinomas (UC) for clinical decision-making is limited. Here, we newly identified and verified CXCL16 as a promising novel biomarker in urine for high grade and muscle invasive UC in a cross-sectional cohort of 308 UC patients, 126 urological hospital controls, and 50 population controls using antibody arrays and ELISA. Median CXCL16 levels in urine was significantly higher in UC patients (273.2 pg/mg creatinine) compared to hospital (148.1 pg/mg) and population controls (85.1 pg/mg) with a particular preference for high grade (460.8 pg/mg), muscle invasive (535.7 pg/mg) and primary UC (327.8 pg/mg) (all p<0.0001). Group differences were confirmed after adjusting or stratifying for potential clinical and individual characteristics, such as leukocyte counts, haematuria, age, gender, and smoking status. In contrast, CXCL16 showed less discriminating power in low grade (244.3 pg/mg), non-muscle invasive (≤pT1, 251.2 pg/mg) and recurrent UC (203.9 pg/mg). In agreement with its function in immune defence, expression of CXCL16 in tissue samples of primary UC patients (n=53) showed only a weak or no immunoreactivity compared to urological hospital controls (n=32). Expression of CXCR6, the G-protein-coupled receptor of CXCL16, remained unchanged. Our findings suggest that evading the immune defence by shedding cell-surface CXCL16 and its increased elimination in urine is a molecular feature of high grade and muscle invasive UC. Therefore, urinary CXCL16 may serve as a useful, simple and non-invasive tool to identify high-risk UC with increased risk of progression at the molecular level.

The distribution of blood concentrations of lead (Pb), cadmium (Cd), chromium (Cr) and manganese (Mn) in residents of the German Ruhr area and its potential association with occupational exposure in metal industry and/or other risk factors.

OBJECTIVE: This study investigated the metal distribution in blood samples from the general population and the risk of having high metal concentration for metal workers. METHODS: Metal concentrations were determined in archived blood samples from 1411 men and 1410 women (median age 59 and 57 years, respectively) collected at baseline (2000-2003) of the prospective Heinz Nixdorf Recall Study. Retrospective information on working in metal industry was obtained from previous follow-up survey (2011-2014). Odds ratios (ORs) with 95% confidence intervals (CI) of having a metal concentration >90th percentile (P90) for working in metal industry were calculated using logistic regression with adjustment for covariates. RESULTS: More men than women worked in metal industry (57 vs. 3 at baseline). Male metal workers had increased blood lead (Pb) (OR: 2.86; 95% CI: 1.38-5.91) and manganese (Mn) (OR: 2.92; 95% CI: 1.46-5.81). Smoking (≥30 cigarettes/day) strongly influenced cadmium (Cd) in blood (OR: 168; 95% CI: 55-510). Women had higher Mn (8.92µg/L) and Cd (0.36µg/L) concentrations than men (Mn: 8.11µg/L; Cd: 0.29µg/L). Blood Pb in women (29.2µg/L) was lower than in men (33.2µg/L). None of the studied risk factors was significantly associated with chromium and nickel concentrations above their 90th percentiles. CONCLUSIONS: In this population-based cohort we found evidence that working in metal industry was predictive for having elevated blood Pb and Mn concentrations. However, the 95th percentiles of all investigated metals were not significantly influenced by metal-related occupations. The present study is supportive for gender-specific reference values to limit occupational exposure to Mn and Pb. The strong influence of smoking on blood Cd hinders establishing reference values.

Replacing cystoscopy by urine markers in the follow-up of patients with low-risk non-muscle-invasive bladder cancer?-An International Bladder Cancer Network project.

RATIONALE: Numerous molecular urine markers for the diagnosis of bladder cancer have been developed and evaluated mostly in case-control settings through the past decades. However, despite all efforts none of them has been included into clinical decision-making and guideline recommendations until today. The aim of this retrospective longitudinal analysis was to investigate if a molecular marker might be able to replace cystoscopy as a primary examination in diagnosis and follow-up of patients with pTa grade 1-2 bladder cancer. MATERIALS AND METHODS: Totally 36 patients (32 men) with pTa grade 1-2 bladder cancer underwent 232 follow-up examinations including urine analysis, cytology, immunocytology (uCyt+), and urethrocystoscopy (UC). Mean age at study entry was 63 years. Patients were observed through a median follow-up interval of 3.8 years. RESULTS: In summary, 47 Transurethral Resection of Bladder Tumors (TURB) procedures were indicated based upon a positive UC (44) or as re-TURB (3) and 33 tumors (plus 1 case of pTa G0) were histopathologically confirmed. Although uCyt+was positive in 12/13 primary tumors (92.3%), sensitivity dropped to 13/20 (65%) in tumor recurrence presumably because of their smaller size. Urine cytology had a sensitivity and a specificity of 30.3% and 94.9%, respectively, but did not improve the sensitivity of uCyt+alone. If UC was based upon a positive uCyt+test, 8/33 tumors (24.2%) would have been overlooked or diagnosed late. In contrast, 173 UCs (74%) would have been saved and 5 presumably unnecessary TURB procedures would not have been indicated. CONCLUSIONS: This longitudinal study suggests a potential of molecular urine tests in replacing cystoscopy in the follow-up of patients with pTa G1-2 bladder cancer. The use of additional markers might further improve sensitivity of urine testing. A prospective randomized study has been initiated to prospectively investigate the performance of a marker panel against UC.

Chromosomal alterations in exfoliated urothelial cells from bladder cancer cases and healthy men: a prospective screening study.

BACKGROUND: Chromosomal instability in exfoliated urothelial cells has been associated with the development of bladder cancer. Here, we analyzed the accumulation of copy number variations (CNVs) using fluorescence in situ hybridization in cancer cases and explored factors associated with the detection of CNVs in tumor-free men. METHODS: The prospective UroScreen study was designed to investigate the performance of UroVysion™ and other tumor tests for the early detection of bladder cancer in chemical workers from 2003-2010. We analyzed a database compiling CNVs of chromosomes 3, 7, and 17 and at 9p21 that were detected in 191,434 exfoliated urothelial cells from 1,595 men. We assessed the accumulation of CNVs in 1,400 cells isolated from serial samples that were collected from 18 cancer cases up to the time of diagnosis. A generalized estimating equation model was applied to evaluate the influence of age, smoking, and urine status on CNVs in cells from tumor-free men. RESULTS: Tetrasomy of chromosomes 3, 7 and 17, and DNA loss at 9p21 were the most frequently observed forms of CNV. In bladder cancer cases, we observed an accumulation of CNVs that started approximately three years before diagnosis. During the year prior to diagnosis, cells from men with high-grade bladder cancer accumulated more CNVs than those obtained from cases with low-grade cancer (CNV < 2: 7.5% vs. 1.1%, CNV > 2: 16-17% vs. 9-11%). About 1% of cells from tumor-free men showed polysomy of chromosomes 3, 7, or 17 or DNA loss at 9p21. Men aged ≥50 years had 1.3-fold more cells with CNVs than younger men; however, we observed no further age-related accumulation of CNVs in tumor-free men. Significantly more cells with CNVs were detected in samples with low creatinine concentrations. CONCLUSIONS: We found an accumulation of CNVs during the development of bladder cancer starting three years before diagnosis, with more altered cells identified in high-grade tumors. Also, a small fraction of cells with CNVs were exfoliated into urine of tumor-free men, mainly exhibiting tetraploidy or DNA loss at 9p21. Whether these cells are preferentially cleared from the urothelium or are artifacts needs further exploration.

Automated quantification of FISH signals in urinary cells enables the assessment of chromosomal aberration patterns characteristic for bladder cancer.

Targeting the centromeres of chromosomes 3, 7, 17 (CEP3, 7, 17) and the 9p21-locus (LSI9p21) for diagnosing bladder cancer (BC) is time- and cost-intensive and requires a manual investigation of the sample by a well-trained investigator thus overall limiting its use in clinical diagnostics and large-scaled epidemiological studies. Here we introduce a new computer-assisted FISH spot analysis tool enabling an automated, objective and quantitative assessment of FISH patterns in the urinary sediment. Utilizing a controllable microscope workstation, the microscope software Scan^R was programmed to allow automatic batch-scanning of up to 32 samples and identifying quadruple FISH signals in DAPI-scanned nuclei of urinary sediments. The assay allowed a time- and cost-efficient, automated and objective assessment of CEP3, 7 and 17 FISH signals and facilitated the quantification of nuclei harboring specific FISH patterns in all cells of the urinary sediment. To explore the diagnostic capability of the developed tool, we analyzed the abundance of 51 different FISH patterns in a pilot set of urine specimens from 14 patients with BC and 21 population controls (PC). Herein, the results of the fully automated approach yielded a high degree of conformity when compared to those obtained by an expert-guided re-evaluation of archived scans. The best cancer-identifying pattern was characterized by a concurrent gain of CEP3, 7 and 17. Overall, our automated analysis refines current FISH protocols and encourages its use to establish reliable diagnostic cutoffs in future large-scale studies with well-characterized specimens-collectives.

Screening for bladder cancer with urinary tumor markers in chemical workers with exposure to aromatic amines.

PURPOSE: To validate urinary markers for the early detection of bladder cancer (BC) in chemical workers. METHODS: UroScreen was conducted as a validation study for tumor markers within the frame of a health surveillance program of the German Social Accident Insurance for active or retired workers with former exposure to aromatic amines. From 2003 to 2010, 1,609 men took part in voluntary annual screens. Cytology, the quantitative NMP22(®) assay, and UroVysion™ were applied to 7,091 urine samples. RESULTS: Fifteen out of 21 tumors were detected following test positivity. The UroVysion/NMP22 panel detected 14 out of 21 tumors versus 8 tumors with cytology alone (sensitivity 66.7 vs. 44.4 %, specificity 94.5 vs. 98.5 %). The sensitivity of the panel increased to 85.7 % in samples collected ≤12 months before diagnosis and when papillomas were excluded, compared to 58.3 % with cytology. About 3 % of NMP22 tests were false-positive. UroVysion results overlapped with cytology due to the preselection of atypical cells. NMP22 was less and UroVysion more frequently positive in diluted urine samples. Leukocytes confounded NMP22 but not UroVysion. The low incidence of BC in this study population yielded low positive predictive values of the markers and high costs per tumor detected with screening. CONCLUSIONS: UroVysion in combination with NMP22 detected more cases than cytology alone, at the expense of a lower specificity. High costs per detected case resulted from a lower BC incidence than in the past when levels of occupational exposure to aromatic amines were higher. Currently, it cannot be recommended to apply these markers for screening in asymptomatic workers. The increase in sensitivity is not balanced by the high costs of UroVysion and the false-positive tests of NMP22.

Chromosomal instability and bladder cancer: the UroVysion(TM) test in the UroScreen study.

UNLABELLED: What's known on the subject? and what does the study add?: UroVysion™ is a multicolour fluorescence in situ hybridisation assay that detects DNA gain at chromosomes 3, 7 and 17 and loss at the 9p21 locus in exfoliated urothelial cells. This cell-based test is time-consuming and costly compared with voided urine cytology or other molecular markers for the early detection of bladder cancer. We determined copy number changes at chromosomes 3, 7 and 17 and at the 9p21 locus with UroVysion in a prospective screening study among chemical workers. Strong correlations between DNA gains yield a similar performance in detecting bladder cancer with just one of the probes for chromosomes 3, 7 or 17 instead of all, supporting the development of a simpler and cheaper assay. OBJECTIVE: To explore changes at chromosomes 3, 7, 17 and 9p21 in order to assess associations with bladder cancer for possible improvements of the UroVysion™ assay regarding screening. SUBJECTS AND METHODS: In all, 1609 men took part in the prospective study UroScreen. Annual screening for bladder cancer was offered to male chemical workers with former exposure to aromatic amines as a voluntary surveillance programme between 2003 and 2010. In all, 191 434 cells in 6517 UroVysion tests were analysed for copy number variations (CNV) at chromosome 3, 7, 17 (gains) and 9p21 (deletions) in 1595 men. We assessed CNVs at single or multiple loci using polysomy indices (PIs, called multiple PI and PI 3, PI 7 and PI 17). We calculated Spearman's rank correlation coefficients (rs ) between these PIs and receiver operating characteristic (ROC) curves with areas under the curves (AUCs). We applied Cox regression to estimate hazard ratios (HRs) to assess the risk of developing bladder cancer. RESULTS: Nine out of 21 bladder tumours detected in 20 participants ('cases') had a positive UroVysion test, including seven high-grade carcinomas and seven overlapping results with a positive cytology. Four cases with negative test results did not attend screening annually. No case was found because of a complete loss of 9p21 in at least 12 cells. There were strong correlations between pairwise combinations of gains at chromosome 3, 7 or 17, ranging between rs = 0.98 and rs = 0.99 in cases and between rs = 0.84 and rs = 0.88 in non-cases (P < 0.001). Associations were less pronounced with CNVs at 9p21 among cases and were lacking in non-cases. Estimates of the relative risk of DNA gain for developing a bladder tumour assessed with PIs (threshold 10% of cells) were 47.7 (95% confidence interval [CI] 18.3-124.1) for the multiple PI, 44.5 (95%CI 16.5-119.9) for PI 3, 34.7 (95%CI 13.1-92.1) for PI 7 and 52.4 (95%CI 20.7-132.6) for PI 17, as well as 7.9 (95%CI 3.0-20.6) for a complete loss of 9p21 (threshold 2.5% of cells), respectively. ROC analyses showed similar AUCs for multiple PI compared with PIs of single chromosomes 3, 7 and 17 (all AUCs between 0.79 and 0.80) and a lower AUC for a homozygous loss of 9p21 (AUC 0.72). CONCLUSIONS: The UroVysion assay showed a reasonable performance in detecting bladder cancer in the present study population and shared positive test results with cytology, which is much cheaper. A simpler, faster and cheaper version of the UroVysion assay might rely on the very strong correlations between gains at chromosomes 3, 7 and 17, resulting in a similar performance in detecting bladder cancer with single-probe PIs compared with the full set of these probes. Loss of 9p21 was less predictive for developing bladder cancer in UroScreen.

Prospective evaluation of fluorescence-in situ-hybridization to detect bladder cancer: results from the UroScreen-Study.

BACKGROUND: UroScreen is a prospective study for early diagnosis of bladder cancer (BC) in chemical workers formerly exposed to aromatic amines, aimed to assess the performance of molecular tumor markers in comparison with urinary cytology. Here we evaluate the cancer-predictive values and potential effect modifiers of fluorescence-in-situ-hybridization (FISH). SUBJECTS AND METHODS: A FISH test was performed in 7,091 urine samples from 1,609 subjects between 2007 and 2010. Cystoscopy was recommended in case of positive or suspicious findings. Logistic regression models were applied to estimate the influence of potential test confounders like urinary creatinine and hematuria on detecting BC. Receiver operating characteristic (ROC) curves for FISH were adjusted for test confounders. Cancer-predictive values were calculated from test results in the last sample before diagnosis. RESULTS: Histopathology revealed 16 incidental BCs and 5 recurrent tumors in 20 study participants. FISH was positive in 9 BC cases of which 7 were high grade. Cytology detected 8 tumors. FISH overlapped with cytology in 7 cases. Sensitivity was 45.0% and PPV (positive predictive value) was 16.4% in all and 53.85% and 13.21% in high-grade tumors. Specificity and negative predictive value (NPV) were 96.97% and 99.26% in all bladder tumors. BC detected during UroScreen was associated with an odds ratio (OR) of 6.88 (95% CI 1.72-27.44) for positive FISH and with an OR of 8.81 (95% CI 1.41-54.96) for gross hematuria. The adjusted area under the curve was 0.77 (95% CI 0.62-0.92) for all and for high-grade lesions (0.85; 95% CI 0.69-1.00). CONCLUSIONS: FISH showed a performance in detecting bladder cancer comparable to cytology but a larger number or false-positive results. It remains to be investigated if chromosomal instability can be detected earlier than morphologic changes of exfoliated bladder cancer cells.

The role of haematuria in bladder cancer screening among men with former occupational exposure to aromatic amines.

UNLABELLED: Study Type - Diagnostic (validating cohort). LEVEL OF EVIDENCE: 1b. What's known on the subject? and What does the study add? Microscopic haematuria (µH) is frequently detected in elderly adults. The American Urological Association recommends the follow-up of subjects with µH on bladder cancer. Whereas gross haematuria is considered an important sign of the presence of bladder cancer, the disease-predictive value of µH is less clear. No association of µH with the development of bladder tumours in a prospective screening cohort of chemical workers was observed. The positive predictive value of µH for bladder cancer was as low as 1.2%. Haematuria interfered with NMP22 but not with cytology and UroVysion(TM) test results. OBJECTIVE: • To assess the positive predictive value (PPV) of microhaematuria (µH) and gross haematuria (GH) in bladder cancer screening and the influence of haematuria on tumour tests in a prospective study. PATIENTS AND METHODS: • From September 2003 to January 2010, 1323 men took part in an annual voluntary bladder cancer screening programme for chemical workers with former exposure to aromatic amines. • In 5315 urine samples haematuria was determined with a dipstick, followed by a microscopic blood cell count in the sediment. Haematuria was categorized into traces, µH and GH. • Urinary leukocytes and other factors were investigated as potential predictors of haematuria using a generalized estimating equation model for repeated urinalysis. The risk of haematuria for positive tumour tests was analysed correspondingly. • The bladder cancer risk was estimated for the highest degree of haematuria occurring during the study with Poisson regression. RESULTS: • As of July 2010, 15 bladder tumours were detected in 14 participants. • GH was found in four out of nine high-grade tumours and associated with a rate ratio of 3.82, 95% confidence interval (CI) 0.50-29.15 for the development of bladder lesions. • The PPV of GH was 11.4%, but only 1.2% for µH. µH occurred in 18.8% of urine samples and was not associated with bladder cancer [rate ratio (RR) 0.72, 95% CI 0.11-4.78]. • Abundant urinary leukocytes were associated with µH [odds ratio (OR) 8.34, 95% CI 2.26-30.69] and even stronger with GH (OR 22.25, 95% CI 6.42-77.06). • Haematuria and leukocytes influenced NMP22 positivity (µH: OR 1.63, 95% CI 1.06-2.51, abundant leukocytes: OR 8.90, 95% CI 1.58-50.16), but not test results for urine cytology and UroVysion(TM) . CONCLUSION: • While the PPV of µH for bladder cancer was low, there was a strong influence of haematuria and leukocytes on the protein-based tumour test NMP22®. • Erythrocytes and leukocytes should be determined at least semi-quantitatively for the interpretation of positive NMP22 test results. • In addition, a panel of tumour tests that includes methods not affected by the presence of erythrocytes or leukocytes such as cytology and UroVysion(TM) would improve bladder cancer screening.

Night work and breast cancer - results from the German GENICA study.

OBJECTIVES: Some epidemiological and animal data indicate that night work might increase the risk for breast cancer. We have investigated the risk in a German population-based case-control study known as GENICA (gene environment interaction and breast cancer). METHODS: The GENICA study involved interviews to assess shift work information in 857 breast cancer cases and 892 controls. We estimated risks of employment status and night shift characteristics using conditional logistic regression models, adjusting for potential confounders. Resampling and bootstrapping were applied to adjust the risk estimates for a potential selection bias. RESULTS: Among 1749 women, 56 cases and 57 controls worked in night shifts for > or =1 year, usually in the healthcare sector (63.0% of controls). Female night workers were more frequently nulliparous and low-educated than day workers (28.6% versus 17.8% and 12.3% versus 9.2%, respectively). Fewer women in night work had ever used post-menopausal hormone therapy (35.7% versus 51.9%). An elevated breast cancer risk was not associated with having ever done shift or night work when compared to women employed in day work only [odds ratio (OR) 0.96, 95% confidence interval (95% CI) 0.67-1.38 and OR 0.91, 95% CI 0.55-1.49, respectively). Women who reported >807 night shifts, the third quartile of the distribution among controls, experienced a breast cancer risk of 1.73 (95% CI 0.71-4.22). Night work for > or =20 years was associated with an OR of 2.48 (95% CI 0.62-9.99) based on 12 cases and 5 controls. CONCLUSIONS: Long-term night work was associated with a modestly, but not significantly, increased breast cancer risk, while having ever done night work was not. The precision of the results was limited by a low prevalence of night work in this study population.