Germline Mutations in the Kallikrein 6 Region and Predisposition for Aggressive Prostate Cancer.

Background: There is a need for markers that can specifically identify individuals at increased risk of harboring aggressive forms of prostate cancer (PCa). Methods: We surveyed the Kallikrein ( KLK ) region ( KLK 1-15) for single-nucleotide polymorphisms (SNPs) associated with aggressive PCa (Gleason Score ≥ 8) in 1858 PCa patients. Discovery cohorts (Swiss arm of the European Randomized Study of Screening for PCa, n = 379; Toronto, Canada, n = 540) and a validation cohort (Prostate, Lung, Colorectal and Ovarian [PLCO] screening trial, n = 939) were analyzed. Fine-mapping within the KLK region was carried out by genotyping and imputation in the discovery cohort, whereas PLCO data were provided through database of Genotypes and Phenotypes ( dbGaP ). The influence of SNPs of interest on biochemical-free survival was evaluated in a cohort of localized PCa from the International Cancer Genome Consortium (ICGC; n = 130) analyzed with next-generation sequencing. Single- and multi-SNP association studies, as well as haplotype analyses, were performed. All statistical tests were two-sided. Results: Several SNPs in very strong linkage disequilibrium in the KLK 6 region and located within the same haplotype (rs113640578, rs79324425, rs11666929, rs28384475, rs3810287), identified individuals at increased risk of aggressive PCa in both discovery (odds ratio [OR] = 3.51-3.64, 95% confidence interval [CI] = 2.01 to 6.36, P = 1.0x10 -5 -8.4x10 -6 ) and validation (OR = 1.89-1.96, 95% CI = 0.99 to 3.71, P = .04-.05) cohorts. The overall test of haplotype association was highly statistically significant in each cohort ( P = 3.5x10 -4 and .006, respectively) and in the three data sets combined ( P = 2.3x10 -5 ). These germline SNPs independently predicted relapse in the ICGC cohort (hazard ratio = 3.15, 95% CI = 1.57 to 6.34, P = .001). Conclusions: Our fine-mapping study has identified novel loci in the KLK 6 region strongly associated with aggressive PCa.

Patients with Lynch syndrome mismatch repair gene mutations are at higher risk for not only upper tract urothelial cancer but also bladder cancer.

BACKGROUND: Lynch syndrome (LS), or hereditary nonpolyposis colorectal cancer, is caused by mutations in mismatch repair (MMR) genes. An increased risk for upper tract urothelial carcinoma (UTUC) has been described in this population; however, data regarding the risk for bladder cancer (BCa) are sparse. OBJECTIVE: To assess the risk of BCa in MMR mutation carriers and suggest screening and management recommendations. DESIGN, SETTING, AND PARTICIPANTS: Cancer data from 1980 to 2007 were obtained from the Familial Gastrointestinal Cancer Registry in Toronto for 321 persons with known MMR mutations: mutL homolog 1, colon cancer, nonpolyposis type 2 (E. coli) (MLH1); mutS homolog 2, colon cancer, nonpolyposis type 1 (E. coli) (MSH2); mutS homolog 6 (E. coli) (MSH6); and PMS2 postmeiotic segregation increased 2 (S. cerevisiae) (PMS2). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Standardized incidence ratios from the Ontario Cancer Registry, using the Surveillance Epidemiology and End Results public database, were used to compare cancer risk in patients with MMR mutations with the Canadian population. Microsatellite instability analysis and immunohistochemistry (IHC) of the MMR proteins were also performed and the results compared with matched sporadic bladder tumors. RESULTS AND LIMITATIONS: Eleven of 177 patients with MSH2 mutations (6.21%, p<0.001 compared with the Canadian population) were found to have BCa, compared with 3 of 129 patients with MLH1 mutations (2.32%, p>0.05). Of these 11 tumors, 81.8% lacked expression of MSH2 on IHC, compared with the matched sporadic cases, which all displayed normal expression of MSH2 and MLH1. The incidence of UTUC among MSH2 carriers was 3.95% (p<0.001), and all tumors were found to be deficient in MSH2 expression on IHC. Mutations in the intron 5 splice site and exon 7 of the MSH2 gene increased the risk of urothelial cancer. Limitations include possible inflated risk estimates due to ascertainment bias. CONCLUSIONS: LS patients with MSH2 mutations are at an increased risk for not only UTUC but also BCa and could be offered appropriate screening.

Long-term prognostic value of the combination of EORTC risk group calculator and molecular markers in non-muscle-invasive bladder cancer patients treated with intravesical Bacille Calmette-Guérin.

BACKGROUND AND OBJECTIVES: To evaluate the long-term prognostic value of the combination of the EORTC risk calculator and proapoptotic, antiapoptotic, proliferation, and invasiveness molecular markers in predicting the outcome of intermediate- and high-risk non-muscle-invasive bladder cancer (NMIBC) treated with intravesical Bacille Calmette-Guérin (BCG) therapy. MATERIALS AND METHODS: This study included 42 patients accrued prospectively presenting with intermediate- to high-risk NMIBC (high-grade T1 tumors or multiple rapidly recurrent tumors refractory to intravesical chemotherapy) treated with transurethral resection (TUR) and BCG. TUR samples were analyzed for the molecular markers p53, p21 waf1/cip, Bcl-2, CyclinD1, and metallothionein 9 (MMP9) using immunohistochemistry. Frequency of positivity, measured as a percentage, was assessed alone or in combination with EORTC risk calculator, for interaction with outcome in terms of recurrence and progression using univariate analysis and Kaplan-Meier survival curves. RESULTS: Median follow-up was 88 months (mean, 99; range, 14-212 months). The overall recurrence rate was 61.9% and progression rate was 21.4%. In univariate analysis, CyclinD1 and EORTC risk groups were significantly associated with recurrence (P value 0.03 and 0.02, respectively), although none of the markers showed a correlation to progression. In combining EORTC risk groups to markers expression status, high-risk group associated with positive MMP9, Bcl-2, CyclinD1, or p21 was significantly correlated to tumor recurrence (log rank P values <0.001, 0.03, 0.02, and 0.006, respectively) and when associated with positive MMP9 or p21, it was significantly correlated to progression (log rank P values 0.01 and 0.04, respectively). CONCLUSION: Molecular markers have a long-term prognostic value when combined with EORTC scoring system and they may be used to improve the predictive accuracy of currently existing scoring system. Larger series are needed to confirm these findings.

Long-term follow-up of T1 high-grade bladder cancer after intravesical bacille Calmette-Guérin treatment.

OBJECTIVE: To report the long-term results of bacille Calmette-Guérin (BCG) intravesical therapy in relation to disease progression and recurrence in primary T1 high-grade (HG) bladder cancer (BC) confirmed by central pathological review. PATIENTS AND METHODS: In all, 136 patients from two university centres (Rotterdam, n = 49; Toronto, n = 87) were diagnosed with primary T1HG BC. One experienced uro-pathologist reviewed all slides, ensuring all cases were indeed HG and that muscle was present in all specimens. Patients were treated with BCG induction (six instillations) after transurethral resection (TUR) of the tumour and followed with cystoscopy and urinary cytology. Predictors for recurrence, progression and survival were assessed with multivariable Cox regression models. RESULTS: Mean (range) follow-up was 6.5 (0.3-21.6) years. There were no significant differences for recurrence (P = 0.52), progression (P = 0.35) and disease-specific survival (DSS) (P = 0.69) between the two centres. Among the cohort, 47 patients (35%) recurred and 42 (30.9%) progressed with a median time to progression of 2.1 years; 16 (38%) of these progressions occurred ≥ 3 years after the initial BCG course; 22 (16%) patients who progressed died from BC. Overall, 96 (71%) patients had no evidence of disease at the last follow-up. Carcinoma in situ was the only independent predictor for recurrence in multivariate analysis (P = 0.011). No independent predictors were found for progression. CONCLUSIONS: Conservative treatment with BCG is a valid option in primary T1HG BC. Nevertheless, the aggressive nature of T1HG BC is evident in the fact that 30% progressed, with a high proportion of these progression events occurring ≥ 3 years after BCG. Caution should be exercised when relying on the long-term effects of BCG, and close follow-up of these patients should not be neglected.

Loss of androgen receptor expression is not associated with pathological stage, grade, gender or outcome in bladder cancer: a large multi-institutional study.

OBJECTIVE: • To investigate androgen receptor (AR) expression in a large series of patients with bladder cancer (BC) because data on a limited number of patients showed that loss of AR expression was associated with invasive BC. PATIENTS AND METHODS: • A total of 472 patients with urothelial bladder carcinoma (UBC) from two institutional centres (Toronto and Dallas) were analysed. Tissue microarrays comprising both non-muscle-invasive UBC (n= 167) and muscle-invasive UBC (n= 305) were accrued and immunohistochemical staining for AR was performed. • We used bright-field microscopy imaging coupled with advanced colour detection software to detect, classify and count stained cellular objects and manual scoring. • Results obtained in Dallas were blindly reviewed and validated in Toronto and samples randomly chosen were further analysed in Rochester, NY, USA. RESULTS: • The AR were positively expressed in 61/472 (12.9%) bladder tumours. No statistically significant difference in AR expression between men and women was observed. • Only 9.0% of non-muscle-invasive BC expressed the AR compared with 15.1% of muscle-invasive tumours (P= 0.059). The highest percentage of AR positivity (28.9% of cases) was found in T2 tumours. • There was no statistically significant difference in death from BC, time to death, or time to recurrence between AR-positive and AR-negative cases. CONCLUSION: • In contrast to previous reports, based on our large BC series, we did not observe a decrease in AR protein expression in bladder tumours with increased pathological stage. Our data do not suggest that loss of AR expression is gender-related nor is it associated with invasive BC.

Nonprimary pT1 nonmuscle invasive bladder cancer treated with bacillus Calmette-Guerin is associated with higher risk of progression compared to primary T1 tumors.

PURPOSE: Few studies have examined the prognostic significance of prior tumor resection(s) in cases of T1 nonmuscle invasive bladder cancer treated with intravesical bacillus Calmette-Guerin. We examined this issue by comparing the prognosis of primary vs nonprimary T1 nonmuscle invasive bladder cancer treated with bacillus Calmette-Guerin. MATERIALS AND METHODS: Patients with pT1 nonmuscle invasive bladder cancer treated with bacillus Calmette-Guerin were identified and tumor pathology was reviewed. Patients were then stratified into primary vs nonprimary tumors, and outcomes were compared using univariate, multivariate and Kaplan-Meier survival analyses, and the Cox regression model adjusting for various clinical and pathological features including, age, gender, tumor size, multifocality, pathological grade and associated carcinoma in situ. RESULTS: The study included 191 patients, 95 (49.7%) with primary and 96 (50.3%) with nonprimary tumors. The clinical and pathological characteristics were comparable. For the primary vs the nonprimary group progression rates were 24.2% vs 39.6%, respectively (HR 2.07, 95% CI 0.98-3.71, multivariate p = 0.03) and the 5-year progression-free survival rates were 71.9% vs 51.5%, respectively (log rank p <0.001). This difference remained significant on multivariate Cox regression analysis (HR 2.53, 95% CI 1.40-4.57, p = 0.002). There was no difference between the groups in recurrence or disease specific mortality. CONCLUSIONS: Nonprimary T1 nonmuscle invasive bladder tumors treated with bacillus Calmette-Guerin carry a significantly higher risk of progression to muscle invasive disease compared to primary tumors. This information may be used in combination with other prognostic factors to identify those at high risk for progression when counseling patients.