A novel precision-engineered microfiltration device for capture and characterisation of bladder cancer cells in urine.

BACKGROUND: Sensitivity of standard urine cytology for detecting urothelial carcinoma of the bladder (UCB) is low, attributable largely to its inability to process entire samples, paucicellularity and presence of background cells. OBJECTIVE: Evaluate performance and practical applicability of a novel portable microfiltration device for capture, enumeration and characterisation of exfoliated tumour cells in urine, and compare it with standard urine cytology for UCB detection. METHODS: A total of 54 urine and bladder wash samples from patients undergoing surveillance for UCB were prospectively evaluated by standard and microfilter-based urine cytology. Head-to-head comparison of quality and performance metrics, and cost effectiveness was conducted for both methodologies. RESULTS: Five samples were paucicellular by standard cytology; no samples processed by microfilter cytology were paucicellular. Standard cytology had 33.3% more samples with background cells that limited evaluation (p<0.001). Microfilter cytology was more concordant (κ=50.4%) than standard cytology (κ=33.5%) with true UCB diagnosis. Sensitivity, specificity and accuracy were higher for microfilter cytology compared to standard cytology (53.3%/100%/79.2% versus 40%/95.8%/69.9%, respectively). Microfilter-captured cells were amenable to downstream on-chip molecular analyses. A 40 ml sample was processed in under 4 min by microfilter cytology compared to 5.5 min by standard cytology. Median microfilter cytology processing and set-up costs were approximately 63% cheaper and 80 times lower than standard cytology, respectively. CONCLUSIONS: The microfiltration device represents a novel non-invasive UCB detection system that is economical, rapid, versatile and has potentially better quality and performance metrics than routine urine cytology, the current standard-of-care.

Long-term outcome in patients with a Gleason score ≤ 6 prostate cancer treated by radical prostatectomy.

OBJECTIVE: • To determine the actual recurrence risk of patients with a Gleason score (GS) ≤ 6 treated with radical retropubic prostatectomy (RRP) and bilateral lymphadenectomy in a cohort with long-term follow-up. PATIENTS AND METHODS: • The USC/Norris Comprehensive Cancer Center database included 3235 consecutive patients who underwent RRP for prostate cancer between January 1972 and December 2005. We identified 1383 patients with a GS ≤ 6 in prostatectomy specimens. Median follow-up was 8.3 years. Data on pathological and clinical characteristics and outcome were prospectively recorded. • Statistical analysis was performed using the stratified log-rank test and stepwise Cox regression analysis. RESULTS: • A GS of 6 was present in 66%, 5 in 27%, 4 in 5% and 3 or 2 in 3% of cases. Tumour classification was pT2N0 (83%), pT3N0 (14%), pT4N0 (0.1%) and any TN1 (2%). • Positive margins were seen in 18%. Estimated PSA and clinical recurrence rate were 14% and 4% after 10 years and 18% and 6% after 15 years, respectively. In multivariate analysis, N-stage (P < 0.001), T-stage (P= 0.02) and margin status (P < 0.001) were associated with PSA recurrence. • N-stage (P < 0.001) and T-stage (P= 0.01) were associated with clinical recurrence. • Overall, patients with a GS ≤ 6 accounted for 26% of all PSA recurrences and for 20% of all patients with clinical recurrences in the database. CONCLUSION: • A relatively small proportion of patients with a GS ≤ 6 cancer developed PSA recurrence and/or overt metastasis. However, these patients account for a substantial minority of those who experienced recurrence and metastasis.

Predicting recurrence and progression of noninvasive papillary bladder cancer at initial presentation based on quantitative gene expression profiles.

BACKGROUND: Currently, tumor grade is the best predictor of outcome at first presentation of noninvasive papillary (Ta) bladder cancer. However, reliable predictors of Ta tumor recurrence and progression for individual patients, which could optimize treatment and follow-up schedules based on specific tumor biology, are yet to be identified. OBJECTIVE: To identify genes predictive for recurrence and progression in Ta bladder cancer at first presentation using a quantitative, pathway-specific approach. DESIGN, SETTING, AND PARTICIPANTS: Retrospective study of patients with Ta G2/3 bladder tumors at initial presentation with three distinct clinical outcomes: absence of recurrence (n=16), recurrence without progression (n=16), and progression to carcinoma in situ or invasive disease (n=16). MEASUREMENTS: Expressions of 24 genes that feature in relevant pathways that are deregulated in bladder cancer were quantified by real-time polymerase chain reaction on tumor biopsies from the patients at initial presentation. RESULTS AND LIMITATIONS: CCND3 (p=0.003) and HRAS (p=0.01) were predictive for recurrence by univariate analysis. In a multivariable model based on CCND3 expression, sensitivity and specificity for recurrence were 97% and 63%, respectively. HRAS (p<0.001), E2F1 (p=0.017), BIRC5/Survivin (p=0.038), and VEGFR2 (p=0.047) were predictive for progression by univariate analysis. Multivariable analysis based on HRAS, VEGFR2, and VEGF identified progression with 81% sensitivity and 94% specificity. Since this is a small retrospective study using medium-throughput profiling, larger confirmatory studies are needed. CONCLUSIONS: Gene expression profiling across relevant cancer pathways appears to be a promising approach for Ta bladder tumor outcome prediction at initial diagnosis. These results could help differentiate between patients who need aggressive versus expectant management.

Molecular markers for bladder cancer: the road to a multimarker approach.

Bladder cancer is the seventh most common malignancy worldwide, with almost 14,000 patients dying from this disease in the USA alone. Because of the need for long-term and frequent follow-up, as well as the paucity of sensitive and specific noninvasive tests, bladder cancer management has the highest cost per patient among all cancer types. Several molecular markers, especially members of the cell cycle regulation and apoptosis pathways, have been investigated. However, no individual marker has been prognostically powerful enough to change clinical management. The combined analysis of a panel of markers spanning different pathways is the most promising approach. We give an overview of the most important molecular markers functioning in crucial pathways and focus on their role in multimarker analysis.

p53 and retinoblastoma pathways in bladder cancer.

A majority of the aggressive, invasive bladder carcinomas have alterations in the p53 and retinoblastoma genes and pathways. Examination of the alterations in the molecules in these pathways that regulate the cell cycle and their effects on the prognosis of bladder cancer are areas of active research. While defects in the p53-Mdm2-p14 axis have been implicated in urothelial cancer, perturbations in the cyclin-dependent kinases and their inhibitors have also been extensively studied in this context. Genetic alterations of the retinoblastoma gene and aberrant post-translational modifications of its protein have also been incriminated in invasive bladder cancer. This article reviews the individual prognostic roles of alterations in these molecules in the context of bladder cancer. Additionally, we review findings from recent studies that are attempting to analyze these markers in combination in an effort to construct molecular panels that can serve as more robust outcome predictors. More importantly, alterations in these molecules are now becoming enticing targets for novel therapeutics. We also review some of these agents that can restore the tumor cells' altered homeostatic mechanisms, thereby having potential in transitional cell carcinoma therapy. Future management of bladder cancer will employ validated marker panels for outcome prediction, and novel genetic and pharmacologic agents that will be able to target molecular alterations in individual tumors based on their respective profiles.