Association of KRT20 and KRT5 with response to neoadjuvant chemotherapy in patients diagnosed with muscle invasive bladder cancer

562

Background: Patients with muscle-invasive bladder cancer (MIBC) that underwent neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC) show improved overall survival. Those with a pathological complete response (pCR) usually have the best prognosis. In the literature, improved response to NAC has been associated with basal tumor characteristics in MIBC so far. The aim of the present study was to examine the association of luminal (KRT20) and basal (KRT5) mRNA expression patterns at transurethral resection (TUR) with pCR at RC after NAC in a contemporary cohort of consecutive MIBC patients. Methods: Clinical Data and formalin fixed paraffin embedded tumor tissue samples from TUR and RC of 49 patients with MIBC were retrospectively analyzed. Using RT-PCR KRT20 and KRT5 mRNA expression were measured in 40-∆Ct values and normalized against the control gene CALM2. Statistical analyses comprised nonparametric and chi2 testing, partition models and spearman correlation analyses. Results: The study cohort had a median age of 63 years and consisted of 38/49 (78%) males. After NAC, 17/49 (35%) patients had cPR. Using partition models, we found that patients with high-KRT20 (≥39.5 ∆Ct) had a higher chance of pCR (57% vs. 26%, p=0.04). Using a cutoff for KRT5 at <38.1 ∆Ct within the subgroup of patients with low-KRT20 (<39.5 ∆Ct, n=35), we found poorest response among low-KRT20/low-KRT5 compared to low-KRT20/high-KRT5 and high-KRT20 (13% vs. 37% vs. 57%, p=0.29), respectively. For low-KRT20/low-KRT5, low-KRT20/high-KRT5 and high-KRT20 median KRT5 was 34.8 vs. 39.5 vs. 34.1 ∆Ct ( p=0.001) and median KRT20 was 37.9 vs. 32.9 vs. 40.1 ∆Ct,( p=0.001), respectively. Conclusions: Patients with MIBC showing high expression of KRT20 were more likely to show pCR at RC after NAC. Moreover, we were able to identify a high risk group of patients with lowKRT20/lowKRT5 that was less likely to achieve pCR at RC after NAC. Our findings are contradicting previous studies and need further verification in larger cohorts. However, our results might be useful for treatment stratification in MIBC patients.

Predictive value of fibroblast growth factor receptor (FGFR) alterations on anti-PD-(L)1 treatment outcomes in patients (Pts) with advanced urothelial cancer (UC): Pooled analysis of real-world data

493

Background: The tumor microenvironment in UC harboring FGFR gene alterations is characterized by decreased T-cell infiltration and low immune marker expression, potentially implicating suboptimal response to immune checkpoint inhibitors. The association between FGFR gene mutations/fusions and anti-PD-(L)1 treatment outcomes in advanced UC was assessed using real-world pt data. Methods: A pooled dataset of matched clinical and genomic data for advanced UC pts treated with anti-PD-(L)1 in any line from the Bladder Cancer Research Initiative for Drug Targets in Germany (BRIDGE) Consortium and UNC-CH was assessed. FGFR status was defined by a prespecified panel of FGFR2/3 mutations and fusions. Overall survival (OS) was analyzed using Kaplan-Meier estimates and Cox proportional hazards models. Multivariate analyses were performed using potential prognostic covariates (sex, age, baseline tumor stage, urothelial histology, smoking history, primary tumor location, and ECOG) in a Cox regression model for OS to assess their impact on the effect of FGFR alterations. Results: Median OS for FGFR+ pts (n=28) who received any line of anti-PD-(L)1 therapy was 9.5 mo vs 7.5 mo for FGFR− pts (n=139) (HR: 1.03, 95% CI: 0.60-1.76, p=0.93). Median OS for pts treated with first-line anti-PD-(L)1 was 5.42 mo in FGFR+ pts (n=10) and was not reached for FGFR− pts (n=31) (HR: 2.06, 95% CI: 0.68-6.24, p=0.19); median OS in second-line anti-PD-(L)1 was 6.5 mo (FGFR+; n=14) vs 5.7 mo (FGFR−; n=86) (HR: 0.89, 95% CI: 0.44-1.81, p=0.74). The multivariate analyses showed a significant trend of poorer OS in FGFR+ pts with first-line anti-PD-(L)1 (HR: 10.42, 95% CI: 1.45-74.97, p=0.02); wide CI may be attributed to small sample size for some categories in several covariates. Conclusions: Treatment with first-line anti-PD-(L)1 in FGFR+ pts may be associated with poorer OS outcomes in FGFR+ pts; however, this trend was not observed in FGFR+ pts treated with any line and second-line anti-PD-(L)1. Investigation of the predictive value of FGFR alterations to immunotherapy outcomes in larger real-world pt datasets is warranted.

Smoking status and PD-L1 mRNA-expression as a predictor of response to neoadjuvant chemotherapy in patients diagnosed with muscle invasive bladder cancer

530

Background: Patients with muscle-invasive bladder cancer (MIBC) that underwent neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC) show improved overall survival. Patients with a pathological complete response (pCR) usually have the best prognosis. In the literature, impaired response to immune checkpoint therapy has been reported in active smokers. The aim of our study was to examine the association of smoking status with pCR at RC after NAC. Moreover, we investigated the interaction of smoking status and Programmed Death Ligand 1 (PD-L1) mRNA expression at transurethral resection (TUR) and pCR prediction at RC after NAC. Methods: Clinical Data and formalin fixed paraffin embedded tumor tissue samples from TUR and RC of 49 patients with MIBC were retrospectively analyzed. Using RT-PCR PD-L1 mRNA expression was measured in 40-∆Ct values and normalized against the control gene CALM2. Smoking status was defined as never, former and active. After NAC, RC was performed and the specimens were evaluated for pCR, defined as ypT0N0M0. Statistical analyses comprised nonparametric and chi2 testing, partition models and spearman correlation analyses. Results: The study cohort had a median age of 63 years and consisted of 38/49 (78%) males. Regarding smoking status 11/49 (22%) were never, 17/49 (35%) were former and 21/49 (43%) were active smokers. After NAC, 17/49 patients (35%) had a pCR. Never/former smokers did not show a higher rate of pCR compared to active smokers (43%vs.24%, p=0.16). Comparing smoking status (never/former vs. active smokers) within the subgroup showing high PD-L1 expression (≥32.1∆Ct), a higher rate of pCR was found in never/former smokers (58% vs. 25%, p=0.047). Conclusions: Never and former smokers with MIBC that show high PD-L1 mRNA expression patterns are more likely to show pCR at RC after NAC. Smoking cessation is important for the management of MIBC patients undergoing NAC and RC.

Same same but different: A Web-based deep learning application revealed classifying features for the histopathologic distinction of cortical malformations

OBJECTIVE

The microscopic review of hematoxylin-eosin-stained images of focal cortical dysplasia type IIb and cortical tuber of tuberous sclerosis complex remains challenging. Both entities are distinct subtypes of human malformations of cortical development that share histopathological features consisting of neuronal dyslamination with dysmorphic neurons and balloon cells. We trained a convolutional neural network (CNN) to classify both entities and visualize the results. Additionally, we propose a new Web-based deep learning application as proof of concept of how deep learning could enter the pathologic routine.

METHODS

A digital processing pipeline was developed for a series of 56 cases of focal cortical dysplasia type IIb and cortical tuber of tuberous sclerosis complex to obtain 4000 regions of interest and 200 000 subsamples with different zoom and rotation angles to train a neural network. Guided gradient-weighted class activation maps (Guided Grad-CAMs) were generated to visualize morphological features used by the CNN to distinguish both entities.

RESULTS

Our best-performing network achieved 91% accuracy and 0.88 area under the receiver operating characteristic curve at the tile level for an unseen test set. Novel histopathologic patterns were found through the visualized Guided Grad-CAMs. These patterns were assembled into a classification score to augment decision-making in routine histopathology workup. This score was successfully validated by 11 expert neuropathologists and 12 nonexperts, boosting nonexperts to expert level performance.

SIGNIFICANCE

Our newly developed Web application combines the visualization of whole slide images with the possibility of deep learning-aided classification between focal cortical dysplasia IIb and tuberous sclerosis complex. This approach will help to introduce deep learning applications and visualization for the histopathologic diagnosis of rare and difficult-to-classify brain lesions.

ANLN and TLE2 in Muscle Invasive Bladder Cancer: A Functional and Clinical Evaluation Based on In Silico and In Vitro Data

: Anilin actin binding protein (ANLN) and transducing-like enhancer protein 2 (TLE2) are associated with cancer patient survival and progression. The impact of their gene expression on progression-free survival (PFS) of patients with muscle invasive bladder cancer (MIBC) treated with radical cystectomy (RC) and subtype association has not yet been investigated. qRT-PCR was used to measure the transcript levels of ANLN and TLE2 in the Mannheim cohort, and validated in silico by The Cancer Genome Atlas (TCGA) cohort. Uni- and multivariate Cox regression analyses identified predictors for disease-specific survival (DSS) and overall survival (OS). In the Mannheim cohort, tumors with high ANLN expression were associated with lower OS and DSS, while high TLE2 expression was associated with a favorable OS. The TCGA cohort confirmed that high ANLN and low TLE2 expression was associated with shorter OS and disease-free survival (DFS). In both cohorts, multivariate analyses showed ANLN and TLE2 expression as independent outcome predictors. Furthermore, ANLN was more highly expressed in cell lines and patients with the basal subtype, while TLE2 expression was higher in cell lines and patients with the luminal subtype. ANLN and TLE2 are promising biomarkers for individualized bladder cancer therapy including cancer subclassification and informed MIBC prognosis.

PD-L1 assessment in urothelial carcinoma: a practical approach

Five programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors are currently approved for treatment of locally advanced or metastatic urothelial carcinoma of the bladder and the upper urinary tract. Due to restrictions by the FDA and EMA first-line treatment with Atezolizumab and Pembrolizumab in platinum-ineligible patients requires immunohistochemical PD-L1 testing. In the second-line setting all drugs are approved without PD-L1 testing. Used PD-L1 assays in clinical trials include the 28-8 pharmDx (Nivolumab), the 22C3 pharmDx (Pembrolizumab), Ventana SP142 (Atezolizumab), and the Ventana PD-L1 SP263 assays (Durvalumab). Differences in antibodies, needed platforms and testing algorithms have raised questions about interchangeability and comparability among these assays and their diagnostic use. We provide a practical review about the current recommendations, used assays and algorithms of PD-L1 testing in urothelial carcinoma to help oncologists, urologists and pathologists to understand analytical features, differences in antibody assays, differences in scoring algorithms and comparability of various PD-L1 assays. We reviewed and summarized published studies from the last four years (2016-2019) on PD-L1 testing in bladder cancer and present a condensed practical guideline including pre-analytical, analytical and test-specific issues.

Co-staining of microRNAs and their target proteins by miRNA in situ hybridization and immunohistofluorescence on prostate cancer tissue microarrays

The co-expression of miRNAs and their target proteins was studied on tissue microarrays from different prostate cancer (PCa) patients. PCa of primary Gleason pattern 4 (GP4), lymph node metastases of GP4, distant metastases, and normal tissue from the transitional and peripheral zones were co-stained by fluorescent miRNA in situ hybridization (miRisH) and protein immunohistofluorescence (IHF). The miRNAs and corresponding target proteins include the pairs miR-145/ERG, miR-143/uPAR, and miR-375/SEC23A. The fluorescence-stained and scanned tissue microarrays (TMAs) were evaluated by experienced uropathologists. The pair miR-145/ERG showed an exclusive staining for miR-145 in the nuclei of stromal cells, both in tumor and normal tissue, and for ERG in the cytoplasm with/without co-expression in the nucleus of tumor cells. The pair miR-143/uPAR revealed a clear distinction between miR-143 in the nuclei of stromal cells and uPAR staining in the cytoplasm of tumor cells. Metastases (lymph node and distant) however, showed tumor cells with cytoplasmic staining for miR-143/uPAR. In normal tissues, beside the nuclei of the stroma cells, gland cells could also express miR-143 and uPAR in the cytoplasm. miR-375 showed particular staining in the nucleoli of GP4 and metastatic samples, suggesting that nucleoli play a special role in sequestering proteins and miRNAs. Combined miRisH/IHF allows for the study of miRNA expression patterns and their target proteins at the single-cell level.

Abstract 4037: Analytical and inter-observer comparability of 4 clinically developed programmed death-ligand 1 (PD-L1) immunohistochemistry assays in advanced clear cell renal cell carcinoma (CCRCC)

Background: PD-L1/programmed cell death-1 (PD-1)-targeting checkpoint inhibitors have shown clinical activity in advanced and metastatic RCC, which correlates with PD-L1 expression on tumor cells (TC) and/or tumor-infiltrating immune cells (IC). We examined the analytical performance and inter-observer agreement of 4 clinically developed assays for PD-L1 expression on IC and TC in locally advanced CCRCC.

Methods: Archived formalin-fixed paraffin-embedded nephrectomy specimens from 30 patients with locally advanced (T2a+) CCRCC were selected from 201 cases based on PD-L1 status per VENTANA SP142 (IC &lt;1%, 1-5%, or &gt;5%; 10 cases each). All selected cases were stained for PD-L1 using VENTANA SP142 and SP263, and DAKO 22C3 and 28-8, each at one site, according to manufacturer protocols. Stainings were blinded with respect to both assay and sample information and scored at 5 sites for PD-L1 expression on IC (% per tumor area) and TC (% of tumor cells). All readers had been trained in scoring IC per tumor area.

Results: Adjusted means of IC staining for PD-L1 varied from 4.00 to 4.90%, and TC from 1.32 to 10.68%, depending on the assay used (Table). Pairwise comparisons of adjusted means between assays revealed small, non-significant differences for IC (-0.9 to 0.3%), while for TC there were significant differences for SP142 v other assays (-9.4 to -5.7%) and for SP263 v 28-8 (-3.7%), and small, non-significant differences for other comparisons (-2.9 to -0.8%). The pre-specified allocation to binary cutoffs (1% or 5%) for IC or TC alone predominantly showed moderate-to-substantial Kappa agreement scores (0.4 to 0.8) for IC and TC between assays for each reader.

Conclusions: This is the first multicenter analytical comparison study of PD-L1 assays in CCRCC. Good-to-high concordance rates across all assays were achieved between trained readers for scoring PD-L1 on IC and for some assays for PD-L1 on TC.

AssayPD-L1 on IC, % (95% CI)*Reader ICC†PD-L1 on TC, % (95% CI)*Reader ICC†VENTANA SP1424.10 (3.33 to 4.86)0.7251.32 (-2.14 to 4.79)0.142VENTANA SP2634.26 (3.49 to 5.02)0.4946.98 (3.52 to 10.45)0.823DAKO 22C34.00 (3.23 to 4.76)0.7019.87 (6.41 to 13.34)0.758DAKO 28-84.90 (4.14 to 5.60)0.42210.68 (7.21 to 14.14)0.778* Sample adjusted means for each assay; † Intra-class correlation per assay between 5 readers.

Citation Format: Ulrich Sommer, Markus Eckstein, Johannes Ammann, Till Braunschweig, Stephan Macher-Goeppinger, Kristina Schwamborn, Stefanie Hieke-Schulz, Bernd Wullich, Manfred Wirth, Wilfried Roth, Ruth Knüchel, Wilko Weichert, Gustavo Baretton, Arndt Hartmann. Analytical and inter-observer comparability of 4 clinically developed programmed death-ligand 1 (PD-L1) immunohistochemistry assays in advanced clear cell renal cell carcinoma (CCRCC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4037.

Abstract 3674: Protein levels of Piwi-like 1 and -2 protein are prognostic factors for muscle invasive urothelial bladder cancer patients

The Piwi-like proteins are essential for stem-cell maintenance and self-renewal in all multicellular organisms. We analyzed the expression of Piwi-like 1 and Piwi-like 2 by immunohistochemistry (IHC) in 95 muscle invasive bladder cancer (MIBC) samples using tissue microarray. Application of an immunoreactive score (IRS) revealed 37 and 45 patients who were Piwi-like 1 and -2 positive (IRS&gt;2). IHC results were correlated with clinico-pathological and survival data. The expression of both proteins was positively correlated with each other, lymph node metastasis and expression of CK20 and GATA 3. A negative correlation for both proteins was detected for disease-specific survival (DSS), recurrence, Ki67/MIB1 proliferation index, and CK5 expression. Detection of Piwi-like 1 protein positivity was associated with poor DSS (P=0.019; log rank test, Kaplan-Meier analysis), and in multivariate Cox’s analysis (adjusted to tumor stage and tumor grade), it was an independent prognostic factor for DSS (RR=2.16; P=0.011). Piwi-like 2 positivity was associated with DSS (P=0.008) and relapse-free survival (RFS; P=0.040), and in multivariate Cox’s analysis, Piwi-like 2 positivity was an independent prognostic factor for DSS (RR=2.46; P=0.004) and RFS (RR=3.0; P=0.003). Most interestingly, in the basal type patient subgroup (CK5+/CK20−), Piwi-like 2 positivity was associated with poorer DSS, OS and RFS (P&lt;0.001, P&lt;0.001 and P=0.006; log rank test). In multivariate analysis, Piwi-like 2 positivity was an independent prognostic factor for DSS (RR=10.49; P=0.001), OS (RR=5.71; P=0.001) and RFS (RR=6.35; P=0.016). In summary, Piwi-like 1 and -2 positivity are associated with clinico-pathological factors and survival. Therefore, both Piwi-like proteins are suggested as biomarkers for MIBC patients.

Citation Format: Markus Eckstein, Rudolf Jung, Katrin Weigelt, Danijel Sikic, Robert Stöhr, Carol Geppert, Abbas Agaimy, Verena Lieb, Arndt Hartmann, Bernd Wullich, Sven Wach, Helge W. Taubert. Protein levels of Piwi-like 1 and -2 protein are prognostic factors for muscle invasive urothelial bladder cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3674.

Erratum: Ultrafast Doublon Dynamics in Photoexcited 1T-TaS_{2} [Phys. Rev. Lett. 120, 166401 (2018)]

This corrects the article DOI: 10.1103/PhysRevLett.120.166401.