Concepts of lines of therapy in cancer treatment: findings from an expert interview-based study

OBJECTIVE

The concept of lines of therapy (LOT) in cancer treatment is often considered for decision making in tumor boards and clinical management, but lacks a common definition across medical specialties. The complexity and heterogeneity of malignancies and treatment modalities contribute to an inconsistent understanding of LOT among physicians. This study assesses the heterogeneity of understandings of the LOT concept, its major dimensions, and criteria from the perspective of physicians of different specialties with an oncological focus in Germany. Semi-structured expert interviews with nine physicians were conducted and evaluated using qualitative content analysis.

RESULTS

Most interviewees agreed that there is no single definition for LOT and found it difficult to explicate their understanding. A majority of experts stated that they had already encountered misunderstandings with colleagues regarding LOT and that they had problems with deciphering LOT from the medical records of their patients. Disagreement emerged about the roles of the following within the LOT concept: maintenance therapy, treatment intention, different therapy modalities, changing pharmaceutical agents, and therapy breaks. Respondents predominantly considered the same criteria as decisive for the definition of LOT as for a change in LOT (e.g., the occurrence of a progression event or tumor recurrence).

[Histomolecular classification of urothelial carcinoma of the urinary bladder : From histological phenotype to genotype and back]

BACKGROUND

Of all urothelial carcinomas (UCs), 25% are muscle invasive and associated with a 5-year overall survival rate of 50%. Findings regarding the molecular classification of muscle-invasive urothelial carcinomas (MIUCs) have not yet found their way into clinical practice.

OBJECTIVES

Prediction of molecular consensus subtypes in MIUCs with artificial intelligence (AI) based on histologic hematoxylin-eosin (HE) sections.

METHODS

Pathologic review and annotation of The Cancer Genome Atlas (TCGA) Bladder Cancer (BLCA) Cohort (N = 412) and the Dr. Senckenberg Institute of Pathology (SIP) BLCA Cohort (N = 181). An AI model for the prediction of molecular subtypes based on annotated histomorphology was trained.

RESULTS

For a five-fold cross-validation with TCGA cases (N = 274), an internal TCGA test set (N = 18) and an external SIP test set (N = 27), we reached mean area under the receiver operating characteristic curve (AUROC) scores of 0.73, 0.8 and 0.75 for the classification of the used molecular subtypes "luminal", "basal/squamous" and "stroma-rich". By training on correlations to individual molecular subtypes, rather than training on one subtype assignment per case, the AI prediction of subtypes could be significantly improved.

DISCUSSION

Follow-up studies with RNA extraction from various areas of AI-predicted molecular heterogeneity may improve molecular classifications and thereby AI algorithms trained on these classifications.

Impact of consensus molecular subtypes on survival with and without adjuvant chemotherapy in muscle-invasive urothelial bladder cancer

AIMS

Adjuvant chemotherapy after radical cystectomy can reduce the risk of recurrence and death in advanced muscle-invasive urothelial bladder cancer (MIBC). Molecular subtypes have been shown to be associated with survival. However, their predictive value to guide treatment decisions is controversial and data to use subtypes as guidance for adjuvant chemotherapy is sparse. We aimed to assess survival rates based on MIBC consensus molecular subtypes with and without adjuvant chemotherapy.

METHODS

Gene expression profiles of 143 patients with MIBC undergoing radical cystectomy were determined from formalin-fixed, paraffin-embedded specimen to assign consensus molecular subtypes. Expression of programmed cell death ligand-1 (PD-L1) and immune cell infiltration were determined using multiplex immunofluorescence. Matched-pair analysis was performed to evaluate the effect of adjuvant chemotherapy on overall survival (OS) for molecular subtypes applying Kaplan-Meier and Cox regression survival analyses.

RESULTS

Samples were luminal papillary: 9.1% (n=13), luminal non-specified: 6.3% (n=9), luminal unstable: 4.9% (n=7), stroma-rich: 27.9% (n=40), basal/squamous (Ba/Sq): 48.9% (n=70) and neuroendocrine-like (NE-like): 2.8% (n=4). Ba/Sq tumours had the highest concentration of PD-L1+ tumour and immune cells. Patients with luminal subtypes had better OS than those with NE-like (HR 0.2, 95% CI 0.1 to 0.7, p<0.05) and Ba/Sq (HR 0.5, 95% CI 0.2 to 0.9, p<0.05). No survival benefit with adjuvant chemotherapy was observed for luminal tumours, whereas Ba/Sq had significantly improved survival rates with adjuvant chemotherapy. Retrospective design and sample size are the main limitations.

CONCLUSION

Consensus molecular subtypes can be used to stratify patients with MIBC. Luminal tumours have the best prognosis and less benefit when receiving adjuvant chemotherapy compared with Ba/Sq tumours.

Optimizing identification of consensus molecular subtypes in muscle-invasive bladder cancer: a comparison of two sequencing methods and gene sets using FFPE specimens

BACKGROUND

Molecular subtypes predict prognosis in muscle-invasive bladder cancer (MIBC) and are explored as predictive markers. To provide a common base for molecular subtyping and facilitate clinical applications, a consensus classification has been developed. However, methods to determine consensus molecular subtypes require validation, particularly when FFPE specimens are used. Here, we aimed to evaluate two gene expression analysis methods on FFPE samples and to compare reduced gene sets to classify tumors into molecular subtypes.

METHODS

RNA was isolated from FFPE blocks of 15 MIBC patients. Massive analysis of 3' cDNA ends (MACE) and the HTG transcriptome panel (HTP) were used to retrieve gene expression. We used normalized, log2-transformed data to call consensus and TCGA subtypes with the consensusMIBC package for R using all available genes, a 68-gene panel (ESSEN1), and a 48-gene panel (ESSEN2).

RESULTS

Fifteen MACE-samples and 14 HTP-samples were available for molecular subtyping. The 14 samples were classified as Ba/Sq in 7 (50%), LumP in 2 (14.3%), LumU in 1 (7.1%), LumNS in 1 (7.1%), stroma-rich in 2 (14.3%) and NE-like in 1 (7.1%) case based on MACE- or HTP-derived transcriptome data. Consensus subtypes were concordant in 71% (10/14) of cases when comparing MACE with HTP data. Four cases with aberrant subtypes had a stroma-rich molecular subtype with either method. The overlap of the molecular consensus subtypes with the reduced ESSEN1 and ESSEN2 panels were 86% and 100%, respectively, with HTP data and 86% with MACE data.

CONCLUSION

Determination of consensus molecular subtypes of MIBC from FFPE samples is feasible using various RNA sequencing methods. Inconsistent classification mainly involves the stroma-rich molecular subtype, which may be the consequence of sample heterogeneity with (stroma)-cell sampling bias and highlights the limitations of bulk RNA-based subclassification. Classification is still reliable when analysis is reduced to selected genes.

Tumor-associated macrophages and Tregs influence and represent immune cell infiltration of muscle-invasive bladder cancer and predict prognosis

INTRODUCTION AND OBJECTIVE

Muscle-invasive urothelial bladder cancer (MIBC) is associated with limited response rates to systemic therapy, risk of recurrence and death. Tumor infiltrating immune cells have been associated with outcome and response to chemo-and immunotherapy in MIBC. We aimed to profile the immune cells in the tumor microenvironment (TME) to predict prognosis in MIBC and responses to adjuvant chemotherapy.

METHODS

We performed multiplex immunohistochemistry (IHC) profiling and quantification of immune and stromal cells (CD3, CD4, CD8, CD163, FoxP3, PD-1, and CD45, Vimentin, αSMA, PD-L1, Pan-Cytokeratin, Ki67) in 101 patients with MIBC receiving radical cystectomy. We used uni- and multivariate survival analyses to identify cell types predicting prognosis. Samples were subdivided using K-means clustering for Treg and macrophage infiltration resulting in 3 clusters, Cluster 1: Treg high, cluster 2: macrophage high, cluster 3: Treg and macrophage low. Routine CD68 and CD163 IHC were analyzed with QuPath in an extended cohort of 141 MIBC.

RESULTS

High concentrations of macrophages were associated with increased risk of death (HR 10.9, 95% CI 2.8-40.5; p < 0.001) and high concentrations of Tregs were associated with decreased risk of death (HR 0.1, 95% CI 0.01-0.7; p = 0.03) in the multivariate Cox-regression model adjusting for adjuvant chemotherapy, tumor and lymph node stage. Patients in the macrophage rich cluster (2) showed the worst OS with and without adjuvant chemotherapy. The Treg rich cluster (1) showed high levels of effector and proliferating immune cells and had the best survival. Cluster 1 and 2 both were rich in PD-1 and PD-L1 expression on tumor and immune cells.

CONCLUSION

Treg and macrophage concentrations in MIBC are independent predictors of prognosis and are important players in the TME. Standard IHC with CD163 for macrophages is feasible to predict prognosis but validation to use immune-cell infiltration, especially to predict response to systemic therapies, is required.

Overexpression of KMT9α Is Associated with Aggressive Basal-like Muscle-Invasive Bladder Cancer

Muscle-invasive bladder cancer (MIBC) is associated with limited response rates to systemic therapy leading to a significant risk of recurrence and death. A recently discovered histone methyltransferase KMT9, acts as an epigenetic regulator of carcinogenesis in different tumor entities. In this study, we investigated the presence and association of histological and molecular subtypes and their impact on the survival of KMT9α in MIBC. We performed an immunohistochemical (IHC) analysis of KMT9α in 135 MIBC patients undergoing radical cystectomy. KMT9α was significantly overexpressed in the nucleus in MIBC compared to normal urothelium and low-grade urothelial cancer. Using the HTG transcriptome panel, we assessed mRNA expression profiles to determine molecular subtypes and identify differentially expressed genes. Patients with higher nuclear and nucleolar KMT9α expression showed basal/squamous urothelial cancer characteristics confirmed by IHC and differentially upregulated KRT14 expression. We identified a subset of patients with nucleolar expression of KMT9α, which was associated with an increased risk of death in uni- and multivariate analyses (HR 2.28, 95%CI 1.28-4.03, p = 0.005). In conclusion, basal-like MIBC and the squamous histological subtype are associated with high nuclear KMT9α expression. The association with poor survival makes it a potential target for the treatment of bladder cancer.

The Oncolytic Adenovirus XVir-N-31, in Combination with the Blockade of the PD-1/PD-L1 Axis, Conveys Abscopal Effects in a Humanized Glioblastoma Mouse Model

Glioblastoma (GBM) is an obligatory lethal brain tumor with a median survival, even with the best standard of care therapy, of less than 20 months. In light of this fact, the evaluation of new GBM treatment approaches such as oncolytic virotherapy (OVT) is urgently needed. Based on our preliminary preclinical data, the YB-1 dependent oncolytic adenovirus (OAV) XVir-N-31 represents a promising therapeutic agent to treat, in particular, therapy resistant GBM. Preclinical studies have shown that XVir-N-31 prolonged the survival of GBM bearing mice. Now using an immunohumanized mouse model, we examined the immunostimulatory effects of XVir-N-31 in comparison to the wildtype adenovirus (Ad-WT). Additionally, we combined OVT with the inhibition of immune checkpoint proteins by using XVir-N-31 in combination with nivolumab, or by using a derivate of XVir-N-31 that expresses a PD-L1 neutralizing antibody. Although in vitro cell killing was higher for Ad-WT, XVir-N-31 induced a much stronger immunogenic cell death that was further elevated by blocking PD-1 or PD-L1. In vivo, an intratumoral injection of XVir-N-31 increased tumor infiltrating lymphocytes (TILs) and NK cells significantly more than Ad-WT not only in the virus-injected tumors, but also in the untreated tumors growing in the contralateral hemisphere. This suggests that for an effective treatment of GBM, immune activating properties by OAVs seem to be of greater importance than their oncolytic capacity. Furthermore, the addition of immune checkpoint inhibition (ICI) to OVT further induced lymphocyte infiltration. Consequently, a significant reduction in contralateral non-virus-injected tumors was only visible if OVT was combined with ICI. This strongly indicates that for an effective eradication of GBM cells that cannot be directly targeted by an intratumoral OV injection, additional ICI therapy is required.

CK5/6 and GATA3 Defined Phenotypes of Muscle-Invasive Bladder Cancer: Impact in Adjuvant Chemotherapy and Molecular Subtyping of Negative Cases

Introduction and Objective

Identifying patients that benefit from cisplatin-based adjuvant chemotherapy is a major issue in the management of muscle-invasive bladder cancer (MIBC). The purpose of this study is to correlate “luminal” and “basal” type protein expression with histological subtypes, to investigate the prognostic impact on survival after adjuvant chemotherapy and to define molecular consensus subtypes of “double negative” patients (i.e., without expression of CK5/6 or GATA3).

Materials and Methods

We performed immunohistochemical (IHC) analysis of CK5/6 and GATA3 for surrogate molecular subtyping in 181 MIBC samples. The mRNA expression profiles for molecular consensus classification were determined in CK5/6 and GATA3 (double) negative cases using a transcriptome panel with 19.398 mRNA targets (HTG Molecular Diagnostics). Data of 110 patients undergoing radical cystectomy were available for survival analysis.

Results

The expression of CK5/6 correlated with squamous histological subtype (96%) and expression of GATA3 was associated with micropapillary histology (100%). In the multivariate Cox-regression model, patients receiving adjuvant chemotherapy had a significant survival benefit (hazard ratio [HR]: 0.19 95% confidence interval [CI]: 0.1–0.4, p &lt; 0.001) and double-negative cases had decreased OS (HR: 4.07; 95% CI: 1.5–10.9, p = 0.005). Double negative cases were classified as NE-like (30%), stroma-rich (30%), and Ba/Sq (40%) consensus molecular subtypes and displaying different histological subtypes.

Conclusion

Immunohistochemical-based classification was associated with histological subtypes of urothelial MIBC. IHC markers like CK5/6 and GATA3 that are used in pathological routine could help to identify patients with basal and luminal tumor characteristics. However, a two-sided classification system might not sufficiently reflect the heterogeneity of bladder cancer to make treatment decisions. Especially the group of IHC-double negative cases, as further analyzed by mRNA expression profiling, are a heterogeneous group with different implications for therapy.

Evaluation of Pre-operative Biopsy, Surgical Procedures and Oncologic Outcomes in Upper Tract Urothelial Carcinoma (UTUC)

Purpose: Discordance between pre-operative biopsy and final pathology for Upper Tract Urothelial Carcinoma (UTUC) is high and optimal management remains controversial. The aim of this study is to evaluate the accuracy of pre-operative biopsy, to identify prognostic factors and to evaluate the effect of adjuvant chemotherapy on survival and oncologic outcome in UTUC. Methods: We analyzed records of patients receiving surgical treatment for UTUC. Pathology of pre-operative biopsy was compared to surgical specimen. We used Kaplan-Meier method to estimate survival probabilities and Cox's proportional hazards models to estimate the association between covariates and event times. Primary endpoint was overall survival (OS). A matched-pair analysis was performed to evaluate the effect of adjuvant chemotherapy. Results: 151 patients underwent surgical treatment (28% open, 36% laparoscopic, 17% robotic radical nephroureterectomy; 14% segmental ureteral resections and 5% palliative nephrectomy) for UTUC and were included in the analysis. Upstaging from <pT1 in endoscopic biopsy to ≥pT1 in final pathology occurred in 61% of patients and upgrading from low-grade to high-grade occurred in 30% of patients. Five-year OS was 59.5%. In the univariate Cox-regression model pathological stage, grade, lymphovascular invasion and positive surgical margins were associated with OS. Matched pair analysis for stage (<pT3; ≥pT3; pN+) and age revealed a significant survival benefit for adjuvant chemotherapy (HR 0.40, 0.14-0.77, p < 0.018) in this cohort. Conclusion: UTUC is often underestimated in pre-operative biopsy, and it is associated with significant mortality. Pathological stage and grade, lymphovascular invasion and lymph node metastases are predictors of oncologic outcome and survival.

[Immuno-oncological approaches in the perioperative therapy of muscle invasive bladder cancer]

Perioperative chemotherapy has become a standard treatment for muscle invasive bladder cancer and is recommended by national and international guidelines. The treatment of metastatic urothelial cancer evolved by the use of immune-modulating therapies like checkpoint inhibitors. Many clinical trials have been initiated which try to evaluate the role of immune checkpoint inhibition in the neoadjuvant and adjuvant setting. These trials focus not only on monotherapy, but also on the combination of checkpoint inhibitors with classical chemotherapy or with local radiation therapy (radioimmunotherapy). In neoadjuvant radioimmunotherapy, the radiation is supposed to act as a sensitizer for the systemic effects of checkpoint inhibition, in addition to the local effects. This review presents and discusses current trials and published results for perioperative immunomodulating treatment-alone or in combination-in muscle invasive bladder cancer.

Molecular lymph node staging for bladder cancer patients undergoing radical cystectomy with pelvic lymph node dissection

OBJECTIVE

Presence of lymph node (LN) metastasis in bladder cancer (BCa) is a main risk factor for tumor recurrence after radical cystectomy (RC). Molecular analysis facilitates detection of small-volume LN metastases with higher sensitivity than standard histopathology. The aim of the present study was to establish molecular LN analysis in BCa patients undergoing RC with lymph node dissection (LND) and to determine its ability to predict tumor recurrence.

PATIENTS AND METHODS

Five transcripts with overexpression in BCa (FXYD3, KRT17, KRT20, SPINK1, UPKII) were evaluated for molecular LN analysis. We included 76 BCa patients from the prospective, randomized surgical phase-III trial (LEA AUO AB 25/02, NCT01215071) investigating extended vs. limited LND at RC. The primary endpoint was recurrence-free survival (RFS). As control, 136 LNs from 45 patients without BCa were analyzed to determine a threshold for pathologic gene expression.

RESULTS

About 1,319 LNs were investigated with molecular and histopathologic examination. Histopathology detected 39 LN metastases in 17 (22%) patients. Of the tested genes FXYD3 performed best and classified all pN+-patients correctly as node-positive (pN+/molN+). In addition, FXYD3 reclassified 43 histopathologic negative LNs and 7 (9%) pN0-patients as molecular node-positive (pN0/molN+). Molecular and histopathologic LN status (pN0/molN0 vs. pN0/molN+ vs. pN+/molN+) was significantly associated with locally advanced disease (P = 0.006) and poor RFS (P < 0.001). Median RFS was not reached in LN-negative patients (pN0/molN0), 45 months (95%CI 8-83) in exclusively molecular positive patients (pN0/molN+) and 9 months (95%CI 5-13) in patients with histopathologic and molecular positive LNs (pN+/molN+).

CONCLUSIONS

Molecular LN analysis with FXYD3 identified additional LN metastases in histopathologic negative LNs and identified patients with elevated risk of tumor recurrence after RC. Thus, molecular LN analysis improves LN staging and might serve as a tool to guide adjuvant treatment.

Radiation therapy before radical cystectomy combined with immunotherapy in locally advanced bladder cancer - study protocol of a prospective, single arm, multicenter phase II trial (RACE IT)

Background

Patients with locally advanced bladder cancer (cT3/4 cN0/N+ cM0) have a poor prognosis despite radical surgical therapy and perioperative chemotherapy. Preliminary data suggest that the combination of radiation and immunotherapy does not lead to excess toxicity and may have synergistic (abscopal) anti-tumor effects. We hypothesize that the combined preoperative application of the PD-1 checkpoint-inhibitor Nivolumab with concomitant radiation therapy of the bladder and pelvic region followed by radical cystectomy with standardized lymphadenectomy is safe and feasible and might improve outcome for patients with locally advanced bladder cancer.

Methods

Study design: “RACE IT” (AUO AB 65/18) is an investigator initiated, prospective, multicenter, open, single arm phase II trial sponsored by Technical University Munich. Study drug and funding are provided by the company Bristol-Myers Squibb.

Study treatment: Patients will receive Nivolumab 240 mg i.v. every 2 weeks for 4 cycles preoperatively with concomitant radiation therapy of bladder and pelvic region (max. 50.4 Gy). Radical cystectomy with standardized bilateral pelvic lymphadenectomy will be performed between week 11–15.

Primary endpoint: Rate of patients with completed treatment consisting of radio-immunotherapy and radical cystectomy at the end of week 15.

Secondary endpoints: Acute and late toxicity, therapy response and survival (1 year follow up).

Main inclusion criteria: Patients with histologically confirmed, locally advanced bladder cancer (cT3/4, cN0/N+), who are ineligible for neoadjuvant, cisplatin-based chemotherapy or who refuse neoadjuvant chemotherapy.

Main exclusion criteria: Patients with metastatic disease (lymph node metastasis outside pelvis or distant metastasis) or previous chemo-, immune- or radiation therapy.

Planned sample size: 33 patients, interim analysis after 11 patients.

Discussion

This trial aims to evaluate the safety and feasibility of the combined approach of preoperative PD-1 checkpoint-inhibitor therapy with concomitant radiation of bladder and pelvic region followed by radical cystectomy. The secondary objectives of therapy response and survival are thought to provide preliminary data for further clinical evaluation after successful completion of this trial. Recruitment has started in February 2019.

Trial registration

Protocol Code RACE IT: AB 65/18; EudraCT: 2018–001823-38; Clinicaltrials.gov: NCT03529890; Date of registration: 27 June 2018.