BTA stat®, NMP22® BladderChek®, UBC® Rapid Test, and CancerCheck® UBC® rapid VISUAL as urinary marker for bladder cancer: Final results of a German multicenter study

INTRODUCTION AND OBJECTIVE

BTA stat®, NMP22® BladderChek®, UBC® Rapid Test, and CancerCheck® UBC® rapid VISUAL are urinary-based rapid tests. This multicenter study is the first study comparing all available rapid tests on a large cohort of bladder cancer patients and healthy controls in one setting.

METHODS

In total 732 urine samples (second morning urine) in a real-world assessment have been analyzed. We evaluated clinical samples from 464 patients with histologically confirmed urothelial tumors of the urinary bladder (17 solitary CIS, 189 low-grade, 187 high-grade nonmuscle invasive, 71 high-grade muscle invasive), 77 patients with No Evidence of Disease (NED), and from 191 healthy controls. Urine samples were analyzed by the BTA stat®, NMP22® BladderChek®, UBC® Rapid Test point-of-care (POC) system using the concile Omega 100 POC reader, and CancerCheck® UBC® rapid VISUAL. Sensitivities and specificities were calculated by contingency analyses.

RESULTS

All investigated urinary markers detected more pathological concentrations in urine of bladder cancer patients compared to tumor-free patients. The calculated diagnostic sensitivities for BTA stat®, NMP22® BladderChek®, UBC® Rapid Test, CancerCheck® UBC® rapid VISUAL, and cytology were 62.4%, 13.4%, 58.2%, 28.6%, 36.2% for low-grade, 83.4%, 49.5%, 84.5%, 63.1%, 71.2% for high-grade nonmuscle invasive, and 95.8%, 35.2%, 76.1%, 50.7%, 67.7% for high-grade muscle-invasive bladder cancer. The specificity was 67.9%, 95.5%, 79.4%, 94.4%, and 83.7%, respectively. The area under the curve (AUC) after receiver operating characteristics (ROC) analysis for high-grade non-muscle-invasive tumors was 0.757, 0.725, 0.819, 0.787, and 0.774, respectively.

CONCLUSIONS

The analysis of more than 700 urine samples offers an objective view on urine-based rapid diagnostics. Elevated pathological concentrations of markers in urine of bladder cancer patients were detected in all investigated tests. The highest sensitivities for high-grade non-muscle-invasive tumors were calculated for BTA stat® and UBC® Rapid Test, whereas NMP22® BladderChek®, and cytology showed the highest specificities. BTA stat® and UBC® Rapid Test have the potential to be used as a clinical valuable urinary protein biomarker for the detection of high-grade non-muscle-invasive bladder cancer patients and could be included in the management of these tumors.

Prediction of response to neoadjuvant chemotherapy of patients with muscle invasive bladder cancer by molecular subtyping and radioligand target quantitation: Preview of the Bladder BRIDGister

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Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NACT) have improved prognosis. Molecular subtypes of bladder cancer differ markedly with regard to sensitivity to cisplatinum based chemotherapy and harbour FGFR treatment targets to various content. Previously we did show that lumina tumors respond better to NACT, while FGFR1 expression is associated with chemo resistance (Ecke et al. 2022). The objective of this study was to determine wether radioligand therapy may be an appropriate option in chemoresistent tumors to justify subsequent prospective validation within the "Bladder BRIDGister". Methods: Formalin fixed paraffin embedded (FFPE) tissues from transurethral resections (TUR) before chemotherapy and cystectomy samples after NACT of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, relative gene expression of subtyping markers (KRT5, KRT20, FGFR1) and radioligand target genes (CXCR4, FAP) were analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, hierarchical clustering, Kruskal-Wallis, chi square and contingency tests were done by JMP 9.0.0 (SAS software). Results: The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being histopathologically node negative. When comparing pretreatment with post treatment samples the median expression of KRT20 dropped 128fold, while FGFR1, CXCR4 and FAP mRNA expression increased 6,8fold, 1,9 fold and 2,9 fold, respectively. FAP was positively associated with KRT5, FGFR1 and CXCR4 in treatment naïve TUR biopsies (r=0.4051 p=0.0141, r=0.6458 p<0.0001 and r=0.7586 p<0.0001, respectively), but negatively associated with KRT20 (r=-0.3879 p=0.0194). As previously described, FGFR1 was negatively associated with pCR (r=-0.6418 p<0.0001). Similarly, CXCR4 and FAP trended to be negatively associated with pCR (r=-0.3181 p=0.0586; r=-0.3072 p=0.0684). Hierarchical clustering revealed that CXCR4 and FAP are elevated in stromal rich, KRT5 & KRT20 negative tumors not responding to NACT. Elevated FAP above median mRNA expression was significantly associated with resistance to NACT (chi2 4.314 p=0,0378). Combining elevated FAP and CXCR4 mRNA expression did identify 28% of the patients to be at high risk of NACT resistance (90%). Conclusions: Expression of the radioligand targets CXCR4 and FAP are associated with basal/stromal enriched tumors and resistance to NACT. Theranostic targeting of CXCR4 and FAP before NACT might increase response towards NACT in this poor prognosis group.

Prediction of response to neoadjuvant chemotherapy of patients with muscle invasive bladder cancer by molecular subtyping and antibody drug conjugate target gene quantitation: Preview of Bladder BRIDGister

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Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NACT) have improved prognosis. Molecular subtypes of bladder cancer differ markedly with regard to sensitivity to cisplatinum based chemotherapy. Previously we did show that luminal tumors respond better to NACT, while FGFR1 expression is associated with chemo resistance (Ecke et al. 2022). The objective of this study was to determine which patients may benefit from Antibody Drug Conjugate (ADC) treatment in addition to NACT to justify subsequent prospective analysis within the "Bladder BRIDGister". Methods: Formalin fixed paraffin embedded (FFPE) tissues from transurethral resections (TUR) before chemotherapy and cystectomy samples after NACT of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, relative gene expression of subtyping markers (KRT5, KRT20, FGFR1) and radioligand target genes (NECTIN4, TROP2) were analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, hierarchical clustering, Kruskal-Wallis, chi square and contingency tests were done by JMP 9.0.0 (SAS software). Results: The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being pathohistologically node negative. When comparing pretreatment with post treatment samples the median expression of KRT20 dropped 128fold, while FGFR1 expression increased 6.8 fold. Interestingly, TROP2 and NECTIN4 mRNA expression also dropped significantly upon NACT by 5.7 fold and 7.1 fold, respectively. TROP2 and NECTIN4 were positively associated with the response marker KRT20 in therapy naïve TUR biopsies (r=0.5562 p=0.0004; r=0.5833 p=0.0002), but negatively associated with the resistance marker FGFR1 (r=-0.2903 p=0,0858; r=-0.3396 p=0,0427). However, TROP2 and NECTIN4 were not associated with pCR in spearman analysis with minor trend for TROP2 (r=0,2139 p=0,2103). Cluster analysis revealed a subgroup of KRT20 positive and FGFR1 negative tumors expression TROP2 and NECTIN4, which achieved 80% pCR. In addition elevated TROP2 and NECTIN4 expression was found in KRT20 positive tumors coexpressing FGFR1 and being resistant to NACT. Conclusions: Expression of the ADC targets TROP2 and NECTIN4 is associated with KRT20 positive, luminal tumors being highly sensitive to neoadjuvant chemotherapy alone. KRT5 positive, basal tumors do exhibit only very low expression of TROP2 and NECTIN4 mRNA. In view of toxicities the addition of TROP2 and NECTIN4 treatment to NACT might be considered only in luminal tumors exhibiting elevated FGFR1 expression as resistance mechanism and therefore do not respond to NACT.

Prediction of Response to Cisplatin-Based Neoadjuvant Chemotherapy of Muscle-Invasive Bladder Cancer Patients by Molecular Subtyping including KRT and FGFR Target Gene Assessment

Patients with muscle-invasive urothelial carcinoma achieving pathological complete response (pCR) upon neoadjuvant chemotherapy (NAC) have improved prognosis. Molecular subtypes of bladder cancer differ markedly regarding sensitivity to cisplatin-based chemotherapy and harbor FGFR treatment targets to various content. The objective of the present study was to evaluate whether preoperative assessment of molecular subtype as well as FGFR target gene expression is predictive for therapeutic outcome—rate of ypT0 status—to justify subsequent prospective validation within the “BladderBRIDGister”. Formalin-fixed paraffin-embedded (FFPE) tissue specimens from transurethral bladder tumor resections (TUR) prior to neoadjuvant chemotherapy and corresponding radical cystectomy samples after chemotherapy of 36 patients were retrospectively collected. RNA from FFPE tissues were extracted by commercial kits, Relative gene expression of subtyping markers (e.g., KRT5, KRT20) and target genes (FGFR1, FGFR3) was analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). Spearman correlation, Kruskal−Wallis, Mann−Whitney and sensitivity/specificity tests were performed by JMP 9.0.0 (SAS software). The neoadjuvant cohort consisted of 36 patients (median age: 69, male 83% vs. female 17%) with 92% of patients being node-negative during radical cystectomy after 1 to 4 cycles of NAC. When comparing pretreatment with post-treatment samples, the median expression of KRT20 dropped most significantly from DCT 37.38 to 30.65, which compares with a 128-fold decrease. The reduction in gene expression was modest for other luminal marker genes (GATA3 6.8-fold, ERBB2 6.3-fold). In contrast, FGFR1 mRNA expression increased from 33.28 to 35.88 (~6.8-fold increase). Spearman correlation revealed positive association of pretreatment KRT20 mRNA levels with achieving pCR (r = 0.3072: p = 0.0684), whereas pretreatment FGFR1 mRNA was associated with resistance to chemotherapy (r = −0.6418: p < 0.0001). Hierarchical clustering identified luminal tumors of high KRT20 mRNA expression being associated with high pCR rate (10/16; 63%), while the double-negative subgroup with high FGFR1 expression did not respond with pCR (0/9; 0%). Molecular subtyping distinguishes patients with high probability of response from tumors as resistant to neoadjuvant chemotherapy. Targeting FGFR1 in less-differentiated bladder cancer subgroups may sensitize tumors for adopted treatments or subsequent chemotherapy.

Association of leucocyte levels in urine with tissue PD-L1 status and immune infiltration into basal bladder cancer subtype in the prospective real-world clinicopathological register trial Bladder BRIDGister

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Background: The objective of the present study was to evaluate whether preoperative standard urine parameters such as leucocyte count in urine samples dominate in particular molecular subtypes of bladder cancer and reflect the immune infiltration status in the tissue in matched urine and TUR biopsy samples from patients being suspicious of bladder cancer and undergoing first TURB within the prospective Real World Experience registry trial "BRIDGister". Methods: For this pilot study paraffin fixed pretreatment tissue samples from the first TURB of 48 pts participating in the BRIDGister trial and matched urine samples were prospectively collected and analyzed. RNA from FFPE tissues were extracted by commercial kits- Relative gene expression of subtyping markers (KRT5, KRT20) by standardized RT-qPCR systems for PD-1, PD-L1, CTLA4 (STRATIFYER Molecular Pathology GmbH, Cologne). In addition urine samples were analyzed for leucocyte and erythrocyte count. Spearman correlation, Kruskal-Wallis, MannWhitney and Sensitivity/Specificity tests were done by JMP 9.0.0 (SAS software). Results: The pilot cohort of the BRIDGister trial consisted of 48 patients (median age: 77, male 65% vs. female 35%) of diverse clinical stages (Benign lesions/no tumor 38%, pTa 23%, pT1 20%, pT2 19%) and WHO 1973 grade (G1 11%, G2 43%, G3 23%). Presence of leucocytes but not erythrocytes was negatively associated with KRT20 (r=-0.4249, p=0.0216) but positive with KRT5 (r=0.3704, p=0.0479). Moreover high levels of leucocytes in urine were positively associated with tumor expression of PD-L1 (r=0.5081, p=0.0041), PD-1 (r=0.5342, p=0.00024) and CTLA4 (r=0.4244, p=0.0194). In contrast there was no significant association of tumor PDL-1, PD-1 and CTLA4 expression with erythrocyte count in urine. Conclusions: Presence of leucotytes in urine is strongly associated with basal subtype and immune cell infiltration into early bladder cancer. As the presence of erythrcytes did not reveal these significant associations, the presence of leucocytes is not due to simple bleeding or tissue vulnerability. Moreover, the strong tumor subtype specificity further demonstrate the basal tumor specificity of urine leucocytes and therefore may be helpful for detecting and monitoring basal bladder cancer in a non invasive fashion. Given the prognostic value of tissue determination of PD-L1, PD-1 and CTLA4 quantitation on mRNA level, these results warrant further investigation to conclude on its impact on outcome prediction (BCG responsiveness, recurrence, progression, etc.), which will be prospectively analyzed in the framework of the ongoing multicenter BRIDGister Real World Experience trial.

FGFR testing and urine-based risk straticfication from matched tissue and urine samples within the prospective real-world clinicopathological register trial: BRIDGister

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Background: The objective of the present study was to assess FGFR mutattions and fusions from matched urine and tissue samples from patients suspicious of bladder cancer and undergoing first TURB within BRIDGister RealWorld Experience trial. Methods: FFPE samples from the first TURB of 39 pts participating in the BRIDGister trial and matched urine samples were prospectively collected and analyzed. RNA from FFPE tissues were extracted by commercial kits and analyzed by Therascreen FGFR IVD kit (Qiagen GmbH, Hilden). In addition extracellular vesicles were centrally isolated for subsequent RNA extraction (exoRNA.Exosome Diagnostics GmbH, Martinsried) and centrall analysis by QIAcuity digital PCR (Qiagen, Hilden). In addition mRNA based profiling of urine was done by dPCR. Concordance, Spearman, Kruskal-Wallis and MannWhitney were analyzed by JMP 9.0.0 (SAS software). Results: The pilot cohort of the BRIDGister trial consisted of 39 patients (median age: 75, male 69% vs female 31%) of diverse clinical stages (Benign lesions/no tumor 23%, pTa 31%, pT1 26%, pT2 21%) and WHO 1973 grade (G1 8%, G2 39%, G3 34%). Based on FFPE tissue testing using Therascreen FGFR IVD kit and exosomal RNA extraction follwoed by dPCR 12 out of 39 patients exhibited FGFR alterations (31%). Comparison with tissue testing as probable gold standard revealed 67% sensitivity, 85% specificity, 67% PPV and 85%NPV. There were 4 patients being FGFR positive for exoRNA from urine with no mutation found in the corresponding TUR biopsy. Determining ERBB2 mRNA by dPCR from urine revealed that high ERBB2 mRNA correlated with higher WHO1973grade, while high FGFR3 mRNA correlated with lower grade tumors (Spearman r=0.4386 p=0.0075 and r=-0.4663 p=0.0042). Similiarly, trends were seen for association of ERBB2 and FGFR3 mRNA with clinical stage tumors in this pilote cohort (Spearman r=0.2359 p=0.0923 and r=-0.2249 p=0.1089). Conclusions: Extraction of exosomal RNA from urine followed by highly sensitive dPCR mutation testing is feasible with good concordance to matched tissue testing. Urine testing might evolve as alternative approach for FGFR3 screening in a non invasive fashion without the need of transurethral biopsy. Interestingly, mRNA assessment of exosomal RNA from urine before TURB correlated with clinical parameters such as WHO Grade 1973 with ERBB2 mRNA being associated with high grade tumors and FGFR3 mRNA being associated with low grade tumors, which is in line with previous tissue tsting results. This indicates the potential to clinically characterize tumor grade and stage before TUR biopsy or surgery which might be helpful for future risk stratification and planning of surgical intervention. Further exploration is warranted and includes the potential of monitoring patients with regard to urine based mutation detection and risk stratification.

Prospective validation of urine based FGFR screening by Uromonitor within the real-world clinicopathological register trial BRIDGister

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Background: The objective of the present study was to prospectively evaluate FGFR mutation detetion in matched urine and tissue samples from patients suspicious of bladder cancer and undergoing first TURB within the framework of the BRIDGister RealWorld Experience trial. Methods: For this pilot study paraffin fixed pretreatment tissue samples from the first TURB of 48 pts participating in the BRIDGister trial and matched urine samples were prospectively collected and analyzed. RNA from FFPE tissues were extracted by commercial kits and analyzed by Therascreen FGFR IVD kit (Qiagen GmbH, Hilden). In addition urine samples were filtered at local urology and filters were shipped for central extraction of cellular DNA (Uromonitor, Porto). Concordance, Kruskal-Wallis, MannWhitney and Sensitivity/Specificity tests were analyzed by JMP 9.0.0 (SAS software). Results: The pilote cohort of the BRIDGister trial consisted of 47 patients (median age: 77, male 65% vs female 35%) of diverse clinical stages (benign lesions/no tumor 38%, pTa 23%, pT1 20%, pT2 19%) and WHO 1973 grade (G1 11%, G2 43%, G3 23%). Based on FFPE tissue testing using Therascreen FGFR IVD kit 10 out of 47 patients exhibited FGFR alterations (25%), while urine filtering for cellular components and subsequent PCR testing revealed 13 out of 40 matched urine sampels were FGFR positive (33%). Comparison with tissue testing as probable gold standard revealed 100% sensitivity, 90% specificity, 77% PPV, 100% NPV as well as high concordance (kappa 0,82, p < 0,0001). There were 3 patients being FGFR positive for Uromonitor from urine with no mutation found in the corresponding TUR biopsy. Conclusions: Filtering urine for cells and subsequent DNA extraction followed by PCR detection results in highly sensitive mutation testing being feasible with good concordance to matched tissue testing. Prospective testing validated the diagnostic accuracy of the Uromonitor FGFR test in a real world setting.

Association of FGFR alterations with FGFR 1-4 gene expression in TUR biopsies and matched NMP22 urine levels in early bladder cancer of the prospective real world clinico-pathological register trial: BRIDGister

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Background: The objective of the present study was to identify molecular charactersitics associated with FGFR positive tumors in matched urine and TUR biopsy samples from patients being suspicious of bladder cancer and undergoing first TURB at the pilot center of the multicentric BRIDGister Real World Experience trial that are helpful for patient management and prognosis. Methods: For this pilot study paraffin fixed pretreatment tissue samples from the first TURB of 28 pts participating in the BRIDGister trial and matched urine samples were prospectively collected and analyzed. RNA from FFPE tissues were extracted by commercial kits and analyzed by Therascreen FGFR IVD kit (Qiagen GmbH, Hilden). Relative gene expression of subtyping markers (KRT5, KRT0) as well as FGFR1, FGFR2, FGFR3, FGFR4, ERBB2 was centrally tested by standardized test systems (STRATIFYER Molecular Pathology GmbH, Cologne). In addition urine samples were analyzed by commercially available urine tests (UBC Rapid, BTA stat, NMP22). Spearman correlation, Kruskal-Wallis, MannWhitney and Sensitivity/Specificity tests were done by JMP 9.0.0 (SAS software). Results: The pilot cohort of the BRIDGister trial consisted of 28 patients (median age: 73, male 71% vs female 29%) of diverse clinical stages (Benign lesions/no tumor 21%, pTa 32%, pT1 21%, pT2 21%) and WHO 1973 grade (G1 7%, G2 43%, G3 21%). Based on FFPE tissue testing using Therascreen FGFR IVD kit 9 out of 28 patients exhibited FGFR alterations (32%). FGFR positive tumors were associated with high expression of FGFR3 mRNA (r = 5.951, p = 0.0011) but low FGFR1 mRNA as well as FGFR4 mRNA (r = -0.3882, p = 0.0412 and r = -0.6305, p = 0.0004, respectively). Interestingly, FGFR alteration was positively associated with the basal marker KRT5 (r = 0.3929, p = 0.0386), but not with luminal KRT20 mRNA expression (r = -0.0208, p = 0.9179). Moreover FGFR3 altered bladder cancer was associated with elevated NMP22 levels in pretreatment urine (r = 0.3978, p = 0.0361). Conclusions: In early bladder cancer FGFR3 alterations are tightly associated with a characteristic FGFR mRNA signature. Mutation/Fusion of FGFR3 results in high FGFR3 but low FGFR1 and FGFR4 mRNA expression, which might be i.a. relevant for the response to FGFR inhibition and important to predict outcome of FGFR inhibitors. Morever FGFR alteration was associated with elevated NMP22 urine levels, which might be helpful for detecting and monitoring FGFR altered bladder cancer in a non invasive fashion. These results warrant further investigation and its impact on outcome prediction (BCG responsiveness, recurrence, proegression, etc) will be prospectively analyzed in the framework of the ongoing multicenter BRIDGister Real World Experience trial.

FGFR testing from matched tissue and urine samples within the prospective real world clinico-pathological register trial BRIDGister

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Background: The objective of the present study was to assess FGFR mutattions and fusions from matched urine and tissue samples from patients suspicious of bladder cancer and undergoing first TURB at the pilot center of the multicentric BRIDGister RealWorld Experience trial Methods: For this pilot study paraffin fixed pretreatment tissue samples from the first TURB of 28 pts participating in the BRIDGister trial and matched urine samples were prospectively collected and analyzed. RNA from FFPE tissues were extracted by commercial kits and analyzed by Therascreen FGFR IVD kit (Qiagen GmbH, Hilden). In addition urine samples were shipped for central isolation of extracellular vesicles and extraction of RNA (exoRNA.Exosome Diagnostics GmbH, Martinsried) and subsequently centrally analyzed by QIAcuity digital PCR (Qiagen, Hilden). Additional urine testing was performed by further technologies including central cytology. Concordance, Kruskal-Wallis, MannWhitney and Sensitivity/Specificity tests were analyzed by JMP 9.0.0 (SAS software). Results: The pilot cohort of the BRIDGister trial consisted of 28 patients (median age: 73, male 71% vs female 29%) of diverse clinical stages (Benign lesions/no tumor 21%, pTa 32%, pT1 21%, pT2 21%) and WHO 1973 grade (G1 7%, G2 43%, G3 21%). Based on FFPE tissue testing using Therascreen FGFR IVD kit 9 out of 28 patients exhibited FGFR alterations (32%). Based on exosomal RNA (exoRNA) and subsequent dPCR testing 8 out of 21 matched urine sampels were FGFR positive (38%). Comparison with tissue testing as probable gold standard revealed 71% sensitivity, 78% specificity, 63% PPV and 85%NPV. There were 3 patients being FGFR positive for exoRNA from urine with no mutation found in the corresponding TUR biopsy. One of these mutations could be validated by independent urine test. Furthermore one tumor harbored two tissue mutations (R248C, Y373C) but three urine mutations (R248C, Y373C, G370C) indicating substantial tumor heterogeneity. One FGFR3-TACC3 fusion was detected from a benign lesion, which was not found by the exosomal urine test. Conclusions: Extraction of exosomal RNA from urine followed by highly sensitive dPCR mutation testing is feasible with good concordance to matched tissue testing. Urine testing bears the potential of detecting additional mutations in a real world setting and might evolve as alternative approach for FGFR3 screening in a non invasive fashion without the need of transurethral biopsy. Discordant cases are further followed up and might reveal validation of mutation status in upcoming recurrences.Further exploration is warranted and includes the potential of monitoring patients with FGFR before and after therapeutic intervention. By the time of the congress an update of the data with approximately 50 matched pairs will be presented.

Characterization of tumor-associated B-cell subsets in patients with colorectal cancer

Purpose:

A precise understanding of the mechanisms by which human immune cell subsets affect tumor biology will be critical for successful treatment of cancer using immunotherapeutic approaches. Recent evidence suggests that B cells can both promote and inhibit the development and progression of tumors. The aim of this study was to characterize the composition of the B-cell infiltrates in colorectal cancers (CRC) in order to gain further insight into the role of B cells in CRC.

Experimental Design:

In this study we characterized B-cell subsets in primary tumors (n=38), metastases (n=6) and blood (n=46) of 51 patients with a diagnosis of CRC and blood of 10 healthy controls. B-cell subsets were analyzed by flow cytometry or immunohistochemistry.

Results:

Peripheral blood of CRC patients contained a higher percentage of memory B cells than that of age-matched healthy controls. Furthermore, the percentage of B cells within tumors was higher than that in the peripheral blood of CRC patients while metastases were typically devoid of tumor-infiltrating B cells. Tumor-associated B cells were enriched for activated and terminally differentiated B cells. Relevant proportions of regulatory B cells could only be detected in advanced cancer and metastases.

Conclusion:

B cells constitute a significant proportion of the immune infiltrate in CRC. The B-cell infiltrate of primary CRC is characterized by an accumulation of terminally differentiated memory B cells or plasma cells suggestive of a specific immune response against the tumor. However advanced tumors and metastases are also infiltrated by a considerable number of regulatory B cells.

Abstract 3654: Prognostic role of androgen receptor in bladder cancer

Aims: Hormone receptors are the prototype predictive marker in breast and prostate cancer. Hormone receptor positive cancers have a better prognosis, increased tropism to metastasize into the bones and respond to endocrine treatment options. The prognostic value of hormone receptor in urothelial carcinoma of the bladder (UCB) is less established. This may in part result from technical limitations of immunhistochemical detection methods. Interestingly, female gender has recently been identified as strong adverse factor in advanced UCB (May et al., 2011). By analyzing whole genome expression data from non-muscle invasive bladder cancer patients, we have evaluated the potential of top candidate genes (ESR1, PGR, AR, CYP19, HER2, RACGAP1) commonly used to stratify breast cancer patients to predict bladder cancer progression. In view of the gender specific effects, we have focused on the prognostic role of androgen receptor expression on tumor invasion, disease progression and survival. Methods: Affymetrix microarray data from 41 non-metastatic bladder cancer patients undergoing curative surgery were analyzed. Prognostic value of androgen receptor mRNA expression was analyzed by unsupervised Cluster analysis, partitioning tests, Mann Whitney tests and Kaplan Meier estimates of cancer specific survival. Results: Cluster analysis in the microarray date of the superficial UCB cohort identified a hormone receptor positive subtype and a proliferation dominated subtype of equal size. Androgen receptor expression was negatively associated with cancer specific death (r=−0,42; p=0,005), while proliferation correlated with increased risk of cancer specific death (r=0,46; p=0,003). In addition, low androgen receptor expression was associated with higher tumor stage (pTa vs pT1-4; p=0,017). In Kaplan Meier analysis, the cancer specific survival was significantly better in tumors exhibiting high androgen receptor levels (80% vs. 20 %; p&lt;0,0001). Discussion: Resembling to some extent the situation in other cancer types, hormone receptors are prognostic factors in early stage bladder cancer. These results may also explain the recently described gender specific effects in bladder cancer. Moreover, these results raise the possibility, that UCB patients may be stratified according to their androgen receptor status in view of prognosis and putative endocrine therapy options.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3654. doi:1538-7445.AM2012-3654

Application of a single needle type for all image-guided biopsies: results of 100 consecutive core biopsies in various organs using a novel tri-axial, end-cut needle

Purpose: To assess feasibility, results and complications in image-guided biopsies using a single needle design in various organs. Materials and methods: 100 consecutive percutaneous biopsies were performed in 54 females and 46 males aged 24–87 years (mean age/standard deviation: 64.5 +/− 12 years) using a full-core end-cut tri-axial full-automatic biopsy needle (18 gauge BioPince ^™, InterV-MDTech, Gainesville, Florida) under CT (n=45) or ultrasound (n=55) guidance. In 63 biopsies a coaxial technique was used. Results: Biopsies were obtained of liver (n=32), lymph nodes (n=17), thyroid (n=11), lung (n=9), adrenal (n=9), pelvis (n=6), chest wall/pleura (n=6), mediastinum (n=4), lytic bone lesions (n=2), retroperitoneum (n=1), muscle (n=1), pancreas (n=1), peritoneum (n=1). Between 1 and 6 (mean/SD 2.83 +/− 0.92) needle passes were performed. In 77 cases a malignant (40 metastases, 37 primary tumours) and in 23 a benign lesion was diagnosed. Of the 23 benign lesions a specific diagnosis was possible in 22. In one case necrosis and haemorrhage was diagnosed. In this patient surgery and autopsy both revealed a mediastinal haematoma of unknown origin. Eight minor complications (mild pain/local haematoma requiring no therapy) and three major complications (three pneumothoraces in nine lung biopsies requiring two aspirations and one drainage) were observed. There was no mortality. Conclusion: Percutaneous image-guided biopsy using the described full-core end-cut needle resulted in a specific diagnosis in 99/100 consecutive biopsies in various organs with a low complication rate. We use this needle type for all CT- or US-guided biopsies in all organs except for solid bone.

Expression of immunohistochemical markers (PCNA, Ki-67, 486p and p53) on paraffin sections and their relation to the recurrence rate of superficial bladder tumors

We present a retrospective study using four different immunohistochemical markers (PCNA, Ki-67, 486p and p53) on paraffin sections from 104 selected cases with primary superficial transitional cell carcinomas of the bladder (59 cases pTa, 45 cases pT1, 40 cases G1, 64 cases G2). 53 of the 104 patients experienced recurrence of their bladder lesion, while 51 remained free of tumor. The distribution of staging, grading and multifocality was comparable in both groups of patients. Overall, the tumors that recurred had a significantly higher proportion of labeled cells for PCNA (p < or = 0.0001), Ki-67 (p < or = 0.006) and 486p (p < or = 0.0001). The latter antigen proved to be the most reliable marker. A less significant difference in staining pattern was found for p53 (p < or = 0.01). Evaluating the predictive value of the various antibodies separately for the groups with G1 vs. G2 carcinomas and pTa vs. pT1 tumors revealed a lower significance for all antibodies. The technique of immunostaining on paraffin sections facilitates further retrospective studies on archival material. These markers may provide additional information about the probability of recurrence of superficial bladder tumors. But at the moment they should only be utilized in selected cases.

Esophagitis due to Pythium insidiosum infection in two dogs

Chronic esophagitis due to Pythium insidiosum infection caused weight loss, dysphagia, and hypersalivation in 2 dogs from rural Tennessee. Although dog 1 presented for evaluation in December 1984 and dog 2 in October 1992, infection likely occurred during the previous summer by drinking fresh pond water containing zoospores. Hematologic testing revealed eosinophilia and hypergammaglobulinemia in one dog. An etiologic diagnosis was not made until postmortem evaluation when hyphae within necrotic and granulomatous cellular infiltrates in the esophageal wall were identified as P insidiosum by immunoperoxidase staining. Failure to culture the organism from the esophageal wall in dog 2 was attributed to refrigeration of the tissues, since refrigeration decreases the survivability of P insidiosum.

[Value of monoclonal antibodies (PC 10, MIB1, p53 and LeuM 1) for assessing the prognosis of patients with squamous epithelial carcinoma of the larynx after partial laser resection]

An immunohistochemical analysis with monoclonal antibodies against Ki-67 (MIB 1), PCNA (PC10), p53 and Lewis X antigen was performed on 47 squamous carcinomas of the larynx after partial laser resection. Ki-67 index and expression of Lewis X antigen correlated significantly with both tumor recurrence rate and tumor-free interval. A much weaker relationship was found for the expression of proliferating cell nuclear antigen (PCNA), and no correlation existed with p53 expression. In conclusion, examination of Ki-67 and Lewis X antigen is thought to provide useful prognostic information concerning laser-resectable squamous carcinomas of the larynx.

[Colloid carcinoma of the urachus. Cytologic diagnosis and differential diagnostic classification]

We report a rare case of colloid carcinoma apparently of urachal derivation. In a patient presenting with nycturia cytological analysis of urine led to a tentative diagnosis of colloid carcinoma of urachal origin. Endoscopic and radiological investigations confirmed this provisional diagnosis. For this reason, the surgical procedure could be properly planned and restricted to the removal of the apex of the bladder and urachus.

Nephrogenic adenoma of the bladder

A nephrogenic adenoma of the bladder in a 4-year-old girl with a past history of urologic surgery for vesicorenal reflux is described. The multifocal tumor was treated by transurethral resection. Relapse occurred 15 months later and was again treated by transurethral resection. Pathological aspects, clinical features and therapeutic considerations of this proliferative lesion are reviewed and discussed.

[Monoclonal antibodies (MIB 1, PC 10, 486p and p53) as prognostic factors for recurrent urothelial carcinoma of the urinary bladder]

Using an immunohistochemical method expression of PCNA, Ki-67, 486p and p53 antigen was investigated in paraffin sections of 119 patients with primary transitional cell carcinoma of the bladder. The purpose of this study was to detect recurring G1 and G2 bladder tumours compared with non-recurrent tumours. A relative large fraction of labelled cells for PCNA and Ki-67 was found in recurring G1 and G2 carcinomas. Moreover, recurrent transitional cell carcinomas showed a more positive staining pattern for 486p and p53, in contrast to non-recurrent carcinomas. Immunohistochemistry of these four antigens seems to yield additional information about the possibility of recurrence in G1 and G2 bladder carcinomas, thus allowing early, i.e. more aggressive, therapy.

Protein conformational "annealing": binding to cytochrome c refolds the active site region of recombinant cytochrome c peroxidase

When initially isolated with heme reconstitution, recombinant cytochrome c peroxidase molecules exhibit a conformation, revealed by visible spectra which observably differ from the corresponding holo proteins isolated from yeast. Binding yeast iso-1 cytochrome c to these recombinant cytochrome c peroxidases (either in solution or via an affinity column) catalyses a local refolding of the recombinant proteins to a form that is indistinguishable from the native (yeast) protein.