[Predictive value of PD-L1 diagnostics]

Clinicopathological characterization of Switch/Sucrose-non-fermentable (Swi/Snf) complex (ARID1A, SMARCA2, SMARCA4)-deficient endocervical adenocarcinoma

BACKGROUND

Subunits of the Switch/Sucrose-non-fermentable (Swi/Snf) complex, such as ARID1A, SMARCA4, SMARCA2, etc., have been implicated in the development of gynecologic cancers. However, their prevalence and clinical implications in endocervical adenocarcinoma (ECA) remain unclear. This study aimed to evaluate the expression of Swi/Snf complex subunits in ECA and characterize the clinicopathological and immune microenvironment features of Swi/Snf-deficient ECA.

METHODS

We evaluated 604 ECA using representative tissue microarrays, collected clinicopathologic data, reviewed histological features, and performed immunohistochemical staining for several Swi/Snf complex subunits, mismatch repair (MMR), immune cell markers, and immune checkpoint ligands proteins.

RESULTS

Among the 604 cases examined, five Swi/Snf subunit expression patterns were identified, including intact expression, deficient expression, 'checkerboard' expression, reduced expression, and heterogeneous expression. Deficiencies of ARID1A (3.97%, 24/604), SMARCA2 (2.32%,14/604), and SMARCA4 (1.49%, 9/604) were observed. Defining Swi/Snf deficiency as loss of any subunit, the overall deficiency rate was 5.96% (36/604). Swi/Snf-deficient ECA tended to advanced FIGO stage (III-IV, P = 0.041), larger tumor size (P < 0.001), deeper stromal invasion (≥ 1/3, P = 0.046), and higher lymph node metastasis rate (P = 0.037). Morphologically, Swi/Snf-deficient ECA displayed frequent poor differentiation (P = 0.001), medullary features (P < 0.001), high nuclear grade (P < 0.001), necrosis (P = 0.001), stromal tumor-infiltrating lymphocytes (sTILs, P < 0.001), peritumoral lymphocyte aggregation (P = 0.001), and tertiary lymphoid structures (TLS, P < 0.001). Immune subset analysis revealed significantly elevated densities of CD3⁺ T cells, CD8⁺ T cells, CD38⁺ plasma cells, CD56⁺ NK cells, CD68⁺ macrophages, and PD-1⁺ T cells in Swi/Snf-deficient ECA (P < 0.05). Swi/Snf-deficient ECA demonstrated higher PD-L1 combined positive score (CPS) positivity (P < 0.001), and was more frequently associated with mismatch repair deficiency (MMRD, P < 0.001). Survival analysis indicated shorter overall survival (median: 53 vs. 64.5 months, P = 0.0307) and disease-free survival (median: 52 vs. 60.5 months, P = 0.0228) in Swi/Snf-deficient ECA patients.

CONCLUSIONS

Swi/Snf complex deficiency is rare but significantly associated with NHPVA, aggressive pathological features, immunologically activated phenotypes, and MMRD. Swi/Snf status evaluation may inform novel therapeutic strategies for ECA patients.

An Immunogenic Cell Death-Related Gene Signature Predicts the Prognosis and Immune Infiltration of Cervical Cancer

Objectives

Immunogenic cell death (ICD) has been demonstrated to play a critical role in the development and progression of malignant tumors by modulating the anti-tumor immune response. However, its function in cervical cancer (CC) remains largely unexplored. In this study, we aimed to construct an ICD-related gene signature to predict patient prognosis and immune cell infiltration in CC.

Methods

The gene expression profiles and clinical data of CC were downloaded from The Cancer Genome Alas (TCGA) and Gene Expression Omnibus (GEO) datasets, serving as the training and testing groups, respectively. An ICD-related gene signature was developed using the LASSO-Cox model. The expression levels of the associated ICD-related genes were evaluated using single-cell data, CC cell lines, and clinical samples in vitro.

Results

Two ICD-associated subtypes (cluster 1 and cluster 2) were identified through consensus clustering. Patients classified into cluster 2 demonstrated higher levels of immune cell infiltration and exhibited a more favorable prognosis. Subsequently, an ICD-related gene signature comprising 3 genes (IL1B, IFNG, and FOXP3) was established for CC. Based on the median risk score, patients in both training and testing cohorts were segregated into high-risk and low-risk groups. Further analyses indicated that the estimated risk score functioned as an independent prognostic factor for CC and influenced immune cell abundance within the tumor microenvironment. The up-regulation of the identified ICD-related genes was further validated in CC cell lines and collected clinical samples.

Conclusion

In summary, the stratification based on ICD-related genes demonstrated strong efficacy in predicting patient prognosis and immune cell infiltration, which also provides valuable new perspectives for the diagnosis and prognosis of CC.

[Neoadjuvant therapy for resectable non-small cell lung cancer]

Treatment perspectives for non-small cell lung cancer (NSCLC) have been significantly expanded by the integration of immune checkpoint inhibitors into multimodal therapy concepts. Currently, combined, immune checkpoint-inhibitor-based therapy concepts are also advancing into early, resectable stages of NSCLC. Neoadjuvant and perioperative chemoimmunotherapy opened up a promising new preoperative treatment approach, but also raises some new questions and challenges. With the expanded perioperative treatment options and the perspective on a further improvement in the absence of recurrence after tumor resection, there is push towards comprehensively collecting therapy-relevant findings for imaging, molecular and histopathological diagnostics at an early stage. All patients with lung carcinoma, regardless of the therapy intention, should be presented to an interdisciplinary tumor board with thoracic oncological expertise. This is regularly given in certified lung cancer centers.A standardized procedure contributes to optimized pre-therapeutic diagnostics and facilitates coordination for the best possible multimodal approach in the interdisciplinary tumor board. In the case of centrally located resectable tumors, for example, neoadjuvant treatment increases the chances of a procedure that is as parenchymal sparing as possible. Some questions cannot yet be answered conclusively. Perioperative systemic therapy with molecular-targeted and immune checkpoint inhibitors is the subject of numerous ongoing studies. The considerable dynamics in newly approved therapies and the development of perioperative therapy concepts require continuous adaptation of diagnostic algorithms and standards. Integration into standard pre-surgical routine makes rapid classification of the relevant findings as well as close coordination between the diagnostic and interventional disciplines essential.

Clinicopathological and immune characterization of mismatch repair deficient endocervical adenocarcinoma

Endocervical adenocarcinoma (ECA) is reported increasingly often in young women, and this aggressive disease lacks effective methods of targeted therapy. Since mismatch repair deficiency (dMMR) is an important biomarker for predicting response to immune checkpoint inhibitors, it is important to investigate the clinicopathological features and immune microenvironment of dMMR ECAs. We assessed 617 ECAs from representative tissue microarray sections, gathered clinicopathologic information, reviewed histological characteristics, and performed immunohistochemical staining for MMR, programmed cell death 1 (PD-L1), and other immune markers. Of 617 ECA samples, 20 (3.2%) cases had dMMR. Among them, loss of MMR-related proteins expression was observed in 17/562 (3.0%) human papilloma virus-associated (HPVA) adenocarcinoma and 3/55 (5.5%) non-HPV-associated (NHPVA) adenocarcinoma. In NHPVA cohort, dMMR status was observed in 3 (3/14, 15.0%) patients with clear cells. dMMR ECAs had a higher tendency to have a family history of cancer, larger tumor size, p16 negative, HPV E6/E7 mRNA in situ hybridization (HPV E6/E7 RNAscope) negative, and lower ki-67 index. Among the morphological variables evaluated, poor differentiation, necrosis, stromal tumor-infiltrating lymphocytes, peritumoral lymphocytes, and lymphoid follicles were easily recognized in the dMMR ECAs. In addition, dMMR ECAs had higher CD3+, CD8+, CD38+, CD68+ and PD-1+ immune cells. A relatively high prevalence of PD-L1 expression was observed in dMMR ECAs. dMMR ECAs were significantly more likely to present with a tumor-infiltrating lymphocytes -high/PD-L1-positive status. In conclusion, dMMR ECAs have some specific morphological features and a critical impact on the immune microenvironment, which may provide insights into improving responses to immunotherapy-included comprehensive treatment for ECAs in the future.

Metformin Treatment Is Not Associated with Altered PD-L1 Expression in Diabetic Patients with Oral Squamous Cell Carcinoma

Background: The anti-neoplastic activity of metformin is a subject of current debate. Preclinical data have suggested that metformin enhances PD-L1 anti-tumor effects in various cancer entities by decreasing insulin levels and inducing energetic stress. However, its impact on PD-L1 expression remains unclear in a clinical setting. Therefore, we aim to investigate the impact of metformin treatment in type 2 diabetes mellitus (DM) patients on PD-L1 expression in patients with oral squamous cell carcinoma (OSCC). Methods: We performed a retrospective analysis of patients with DM and OSCC treated at our tertiary referral center over a period of 12 years. The tumor proportion score (TPS), immune cell score (IC), and combined positive score (CPS) were used to quantify PD-L1 expression. PD-L1 expression of patients receiving metformin was compared to a control group without metformin prescription. Results: A total of 68 patients diagnosed with OSCC and DM were analyzed, with 24 receiving and 44 not receiving metformin therapy. No statistically significant differences were identified between the metformin and non-metformin groups for any of the scores (TPS: p = 0.818; IC: p = 0.748; CPS: p = 0.387). Conclusions: In contrast to previous studies, we could not find significant differences in PD-L1 expression between patients with and without metformin intake. Further research needs to shed light on the exact mechanism of metformin in different tumor entities. A comprehensive understanding of metformin's role in cancer therapy could provide valuable insights for potential use of metformin as an adjuvant treatment to immune checkpoint therapy.

Evaluation of pathological response to neoadjuvant chemotherapy in locally advanced cervical cancer

Neoadjuvant chemotherapy (NACT) is a viable therapeutic option for women diagnosed locally advanced cervical cancer (LACC). However, the factors influencing pathological response are still controversial. We collected pair specimens of 185 LACC patients before and after receiving NACT and conducted histological evaluation. 8 fresh tissues pre-treatment were selected from the entire cohort to conducted immune gene expression profiling. A novel pathological grading system was established by comprehensively assessing the percentages of viable tumor, inflammatory stroma, fibrotic stroma, and necrosis in the tumor bed. Then, 185 patients were categorized into either the good pathological response (GPR) group or the poor pathological response (PPR) group post-NACT, with 134 patients (72.4%, 134/185) achieving GPR. Increasing tumor-infiltrating lymphocytes (TILs) and tumor-infiltrating lymphocytes volume (TILV) pre-treatment were correlated with GPR, with TILV emerging as an independent predictive factor for GPR. Additionally, CIBERSORT analysis revealed noteworthy differences in the expression of immune makers between cPR and non-cPR group. Furthermore, a significantly heightened density of CD8 + T cells and a reduced density of FOXP3 + T cells were observed in GPR than PPR. Importantly, patients exhibiting GPR or inflammatory type demonstrated improved overall survival and disease-free survival. Notably, stromal type was an independent prognostic factor in multivariate analysis. Our study indicates the elevated TILV in pre-treatment specimens may predict a favorable response to NACT, while identifying stromal type in post-treatment specimens as an independent prognostic factor. Moreover, we proposed this pathological grading system in NACT patients, which may offer a more comprehensive understanding of treatment response and prognosis.

Genome-Wide Methylation Analysis in Two Wild-Type Non-Small Cell Lung Cancer Subgroups with Negative and High PD-L1 Expression

We conducted a pilot study to analyze the differential methylation status of 20 primary acinar adenocarcinomas of the lungs. These adenocarcinomas had to be wild type in mutation analysis and had either high (TPS > 50%; n = 10) or negative (TPS < 1%; n = 10) PD-L1 status to be integrated into our study. To examine the methylation of 866,895 specific sites, we utilized the Illumina Infinium EPIC bead chip array. Both hypermethylation and hypomethylation play significant roles in tumor development, progression, and metastasis. They also impact the formation of the tumor microenvironment, which plays a decisive role in tumor differentiation, epigenetics, dissemination, and immune evasion. The gained methylation patterns were correlated with PD-L1 expression. Our analysis has identified distinct methylation patterns in lung adenocarcinomas with high and negative PD-L1 expression. After analyzing the correlation between the methylation results of genes and promoters with their pathobiology, we found that tumors with high expression of PD-L1 tend to exhibit oncogenic effects through hypermethylation. On the other hand, tumors with negative PD-L1 expression show loss of their suppressor functions through hypomethylation. The suppressor functions of hypermethylated genes and promoters are ineffective compared to simultaneously activated dominant oncogenic mechanisms. The tumor microenvironment supports tumor growth in both groups.

NGS-Guided Precision Oncology in Breast Cancer and Gynecological Tumors-A Retrospective Molecular Tumor Board Analysis

Background: Precision oncology treatments are being applied more commonly in breast and gynecological oncology through the implementation of Molecular Tumor Boards (MTBs), but real-world clinical outcome data remain limited. Methods: A retrospective analysis was conducted in patients with breast cancer (BC) and gynecological malignancies referred to our center's MTB from 2018 to 2023. The analysis covered patient characteristics, next-generation sequencing (NGS) results, MTB recommendations, therapy received, and clinical outcomes. Results: Sixty-three patients (77.8%) had metastatic disease, and forty-four patients (54.3%) had previously undergone three or more lines of systemic treatment. Personalized treatment recommendations were provided to 50 patients (63.3%), while 29 (36.7%) had no actionable target. Ultimately, 23 patients (29.1%) underwent molecular-matched treatment (MMT). Commonly altered genes in patients with pan-gyn tumors (BC and gynecological malignancies) included TP53 (n = 42/81, 51.9%), PIK3CA (n = 18/81, 22.2%), BRCA1/2 (n = 10/81, 12.3%), and ARID1A (n = 9/81, 11.1%). Patients treated with MMT showed significantly prolonged progression-free survival (median PFS 5.5 vs. 3.5 months, p = 0.0014). Of all patients who underwent molecular profiling, 13.6% experienced a major clinical benefit (PFSr ≥ 1.3 and PR/SD ≥ 6 months) through precision oncology. Conclusions: NGS-guided precision oncology demonstrated improved clinical outcomes in a subgroup of patients with gynecological and breast cancers.

The Vanishing Clinical Value of PD-L1 Status as a Predictive Biomarker in the First-Line Treatment of Urothelial Carcinoma of the Bladder

BACKGROUND

Our study endeavors to elucidate the clinical implications of PD-L1 positivity in individuals afflicted with advanced urothelial carcinoma of the bladder (UCB).

METHODS

Patients with advanced UCB were prospectively enrolled following a radical cystectomy (RC) performed within January 2017 to December 2022 at our tertiary referral center. The clinical outcome, defined as the progression-free survival (PFS) and overall survival (OS) on systemic treatment, was analyzed using an χ2-test, Mann-Whitney U-test, the Kaplan-Meier method, and a log-rank test.

RESULTS

A total of 648 patients were included following an RC performed within January 2017 to December 2022. Their PD-L1 status was analyzed with the primary PD-L1-specific antibody (clone SP263, Ventana) and defined both by the CPS and IC-score in 282 patients (43.5%) with a high risk (pT3-pT4 and/or lymph node involvement) or metastatic UCB. While the median PFS was significantly prolonged 5-fold in PD-L1+ patients, we found no difference in OS, regardless of PD-L1 status, or treatment regimen.

CONCLUSIONS

While PD-L1 positivity indicates prolonged PFS, the presence of PD-L1 does not influence OS rates, suggesting its limited usefulness as a prognostic biomarker in bladder cancer. However, the positive correlation between an PD-L1 status and a sustained response to ICI treatments indicates its potential role as a predictive biomarker. Further research is required to understand how the predictive value of PD-L1 positivity may extend to the use of ICIs in combination with antibody-drug conjugates.

High tumour mutational burden is associated with strong PD-L1 expression, HPV negativity, and worse survival in penile squamous cell carcinoma: an analysis of 165 cases

Penile squamous cell carcinoma (pSCC) is a rare tumour with a variable prognosis. More prognostic markers linked to mutational signatures and the tumour immune microenvironment are needed. A cohort made up of 165 invasive pSCC was retrospectively analysed using formalin-fixed, paraffin-embedded tumour tissue, focusing on tumour mutational burden (TMB), programmed death ligand 1 (PD-L1) expression, microsatellite instability (MSI), the number of tumour infiltrating lymphocytes (TILs) expressing cytotoxic T-lymphocyte-associated protein 4 (CTLA4), HPV status determined by p16 immunohistochemistry, and several traditional histopathological variables. High TMB (>10 mut/Mb) was associated with high PD-L1 expression (TPS 50-100%), and HPV-negative status. High PD-L1 expression was linked to HPV negativity, a high number of intratumoural CTLA4+ cells, and brisk lymphocytic infiltrate. High TMB was a significant predictor of shorter overall survival (OS) in both univariate and multivariate analysis when using a median cut-off value of 4.3 mut/Mb, but not when using an arbitrary cut-off of 10 mut/Mb. Low CTLA4+ cell infiltration at the tumour invasion front was a marker of shorter OS and cancer-specific survival in both univariate and multivariate analysis. PD-L1 expression had no significant impact on prognosis. Only two cases were MSI high. The results support the hypothesis of two aetiological pathways in pSCC cancerogenesis: (1) SCC linked to HPV infection characterised by low TMB, less common PD-L1 expression, and a lower number of TILs; and (2) SCC linked to chronic inflammation leading to a high number of acquired mutations (high TMB), HPV negativity, increased neoantigen production (i.e., PD-L1), and high immune cell infiltration.

Enhancing anti-CD274 (PD-L1) targeting through combinatorial immunotherapy with bispecific antibodies and fusion proteins: from preclinical to phase II clinical trials

INTRODUCTION

Immune checkpoint inhibitors have achieved great success in the treatment of many different types of cancer. Programmed cell death protein ligand 1 (PD-L1, CD274) is a major immunosuppressive immune checkpoint and a target for several already approved monoclonal antibodies. Despite this, novel strategies are under development, as the overall response remains low.

AREAS COVERED

In this review, an overview of the current biomarkers for response to PD-L1 inhibitor treatment is given, followed by a discussion of potential novel biomarkers, including tumor mutational burden and circulating tumor DNA. Combinatorial immunotherapy is a potential novel strategy to increase the response to PD-L1 inhibitor treatment and currently, several interesting bispecific antibodies as well as bispecific fusion proteins are undergoing early clinical investigation. We focus on substances targeting PD-L1 and a secondary target, and a secondary immunomodulatory target like CTLA-4, TIGIT, or CD47.

EXPERT OPINION

Overall, the presented studies show anti-tumor activity of these combinatorial immunotherapeutic approaches. However, still relatively low response rates suggest a need for better biomarkers.

Differential Immunoexpression of Inhibitory Immune Checkpoint Molecules and Clinicopathological Correlates in Keratoacanthoma, Primary Cutaneous Squamous Cell Carcinoma and Metastases

Beyond established anti-programmed cell death protein 1/programmed cell death ligand 1 immunotherapy, T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domain (TIGIT) and its ligand CD155 are promising novel inhibitory immune checkpoint targets in human malignancies. Yet, in cutaneous squamous cell carcinoma, evidence on the collective expression patterns of these inhibitory immune checkpoints is scarce. Complete tumour sections of 36 cutaneous squamous cell carcinoma, 5 cutaneous metastases and 9 keratoacanthomas, a highly-differentiated, squamoproliferative tumour, with disparately benign biologic behaviour, were evaluated by immunohistochemistry for expression of programmed cell death ligand 1 (Tumor Proportion Score, Immune Cell Score), TIGIT, CD155 and CD8+ immune infiltrates. Unlike keratoacanthomas, cutaneous squamous cell carcinoma displayed a strong positive correlation of programmed cell death ligand 1 Tumor Proportion Score and CD115 expression (p < 0.001) with significantly higher programmed cell death ligand 1 Tumor Proportion Score (p < 0.001) and CD155 expression (p < 0.01) in poorly differentiated G3-cutaneous squamous cell carcinoma compared with keratoacanthomas. TIGIT+ infiltrates were significantly increased in programmed cell death ligand 1 Immune Cell Score positive primary tumours (p = 0.05). Yet, a strong positive correlation of TIGIT expression with CD8+ infiltrates was only detected in cutaneous squamous cell carcinoma (p < 0.01), but not keratoacanthomas. Providing a comprehensive overview on the collective landscape of inhibitory immune checkpoint expression, this study reveals associations of novel inhibitory immune checkpoint with CD8+ immune infiltrates and tumour differentiation and highlights the TIGIT/CD155 axis as a potential new target for cutaneous squamous cell carcinoma immunotherapy.

Immune Checkpoint Inhibitor Plus Chemotherapy as First-Line Treatment for Advanced Gastric or Gastroesophageal Junction Cancer: A Systematic Review and Meta-Analysis

Background: Immune checkpoint inhibitor (ICI) plus chemotherapy is effective in advanced gastric or gastroesophageal junction (G/GEJ) cancer. This study aims to evaluate the clinical effect of first-line immunotherapy in combination with chemotherapy for advanced G/GEJ cancer. Methods: PubMed, Web of Science, Embase and Cochrane databases were systematically searched from the inception of the databases to December 2021. Randomized trials comparing ICI plus chemotherapy with chemotherapy in first-line treatment for advanced G/GEJ cancer were included. The outcomes were overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs). Analyses were performed in Stata 14.0 software. The study protocol was registered with PROSPERO, number CRD42022300907. Results: Five trials were included for analysis, involving 2, 814 patients. ICI plus chemotherapy can significantly improve OS (hazards ratio [HR], 0.86; 95% CI 0.78-0.94; P = .002), PFS (HR, 0.79; 95% CI 0.63-0.99; P ＜ .001) and ORR (relative ratio [RR], 1.20; 95% CI 1.11-1.30; P < .001). In safety analyses, there were no significant differences in incidence of all AEs, treatment-related adverse event (TRAE), TRAE of grade 3 or higher, serious TRAE and TRAE leading to death between two arms (P > .05). Conclusions: ICI plus chemotherapy is more effective first-line treatment for advanced G/GEJ cancer in contrast to chemotherapy regrading to improving OS, PFS and ORR, without increasing TRAE risk. This study will redefine the role of ICI in combination with chemotherapy in the first-line setting for G/GEJ cancer, and provide reference for clinical treatment.

HER2 positivity predicts BCG unresponsiveness and adaptive immune cell exhaustion in EORTC risk-stratified cohort of bladder cancer

Introduction

Predicting the response to Bacillus Calmette-Guérin (BCG) therapy in high-risk patients with non-muscle invasive bladder cancer (NMIBC) is crucial, as failure may necessitate interventions, such as radical cystectomy or salvage therapy. With the recent classification of genetic class 2a (which has HER2 protein abundance as its signature mutation of ERBB2), evaluating its prognostic role and relationship with BCG response could yield important results.

Methods

This retrospective study included 160 patients with NMIBC who underwent transurethral resection of bladder tumors at Gangneung Asan Hospital between 2000 and 2013 and were stratified based on the European Organization for Research and Treatment of Cancer (EORTC) risk criteria. In addition, we analyzed a subset of 67 patients who had received BCG induction therapy to identify factors predictive of BCG treatment response. Univariate and multivariate analyses were used to assess the impact of clinicopathological factors, HER2 positivity, and EORTC risk on recurrence, progression, survival, and BCG response. Each variable's prognostic significance was determined using the Kaplan-Meier analysis. The tumor microenvironments (TMEs) were evaluated in relation to HER2 and EORTC risk.

Results

Patients with HER2+ had a higher median age, a greater prevalence of high-grade tumors, and more frequent recurrences. The univariate analysis demonstrated that the HER2+, intermediate (vs. low-risk) high (vs. low-risk), and EORTC recurrence risk groups were significantly associated with recurrence. In patients treated with BCG, only the HER2+ status predicted recurrence. In the univariate analysis for progression, age, high EORTC progression risk (vs. low-to-intermediate), HER2+, and programmed death-ligand 1 positive (PD-L1+) were significant factors. In multivariate analyses for progression, age, high EORTC progression risk, and PD-L1+ were significant factors for progression. HER2 expression was associated with the TME, influencing the proportion of PD-L1+ cells, as well as other markers of PD-1, CD8, and Ki67.

Conclusion

The HER2+ status may be related to genetic characteristics that appear more frequently in older age, which suggests a potential for predicting the recurrence and response to BCG treatment. Additionally, analyzing TME trends of aggressive adaptive immune response characterized by HER2 expression provides insight into recurrence and BCG response mechanisms.

Identifying Predictive Biomarkers for Head and Neck Squamous Cell Carcinoma Response

The 5-year survival rate for head and neck squamous cell carcinoma (HNSCC) is approximately 65%. In addition to radio-chemotherapy, immunotherapy is an approach in the treatment of advanced HNSCC. A better understanding of the immune context would allow personalized treatment by identifying patients who are best suited for different treatment options. In our discovery cohort, we evaluated the expression profiles of CMTM6, PD-L1, CTLA-4, and FOXP3 in 177 HNSCCs from Caucasian patients of all tumor stages and different treatment regimens, correlating marker expression in tumor and immune cells with outcomes. Patients with CMTM6high-expressing tumors had a longer overall survival regardless of treatment. This prognostic benefit of CMTM6 in HNSCC was validated in an independent cohort. Focusing on the in the discovery cohort (n = 177), a good predictive effect of CMTM6high expression was seen in patients receiving radiotherapy (p = 0.07; log rank), but not in others. CMTM6 correlated with PD-L1, CTLA-4 and FOXP3 positivity, with patients possessing CMTM6high/FOXP3high tumors showing the longest survival regardless of treatment. In chemotherapy-treated patients, PD-L1 positivity was associated with longer progression-free survival (p < 0.05). In the 27 patients who received immunotherapy, gene expression analysis revealed lower levels of CTLA-4 and FOXP3 with either partial or complete response to this treatment, while no effect was observed for CMTM6 or PD-L1. The combination of these immunomodulatory markers seems to be an interesting prognostic and predictive signature for HNSCC patients with the ability to optimize individualized treatments.

Mathematical Modeling of Non-Small-Cell Lung Cancer Biology through the Experimental Data on Cell Composition and Growth of Patient-Derived Organoids

Mathematical models of non-small-cell lung cancer are powerful tools that use clinical and experimental data to describe various aspects of tumorigenesis. The developed algorithms capture phenotypic changes in the tumor and predict changes in tumor behavior, drug resistance, and clinical outcomes of anti-cancer therapy. The aim of this study was to propose a mathematical model that predicts the changes in the cellular composition of patient-derived tumor organoids over time with a perspective of translation of these results to the parental tumor, and therefore to possible clinical course and outcomes for the patient. Using the data on specific biomarkers of cancer cells (PD-L1), tumor-associated macrophages (CD206), natural killer cells (CD8), and fibroblasts (αSMA) as input, we proposed a model that accurately predicts the cellular composition of patient-derived tumor organoids at a desired time point. Combining the obtained results with "omics" approaches will improve our understanding of the nature of non-small-cell lung cancer. Moreover, their implementation into clinical practice will facilitate a decision-making process on treatment strategy and develop a new personalized approach in anti-cancer therapy.

PD-L1 and HIF-2α Upregulation in Head and Neck Paragangliomas after Embolization

Hypoxia activates pathways associated with tumor progression, metastatic spread, and alterations in the immune microenvironment leading to an immunosuppressive phenotype. In particular, the upregulation of PD-L1, a target for therapy with checkpoint inhibitors, is well-studied in several tumors. However, the relationship between hypoxia and PD-L1 regulation in pheochromocytomas and paragangliomas (PPGL), and especially in paragangliomas treated with embolization, is still largely unexplored. We investigated the expression of the hypoxia-marker HIF-2α and of PD-L1 in a PPGL-cohort with and without embolization as potential biomarkers that may predict the response to treatment with HIF-2α and checkpoint inhibitors. A total of 29 tumor samples from 25 patients who were operated at a single center were included and analyzed utilizing immunohistochemistry (IHC) for PD-L1 and HIF-2α. Embolization prior to surgery was performed in seven (24%) tumors. PD-L1 expression in tumor cells of head and neck paragangliomas (HNPGLs) receiving prior embolization (median PD-L1 positivity: 15%) was significantly higher as compared to PD-L1 expression in HNPGLs without prior embolization (median PD-L1 positivity: 0%) (p = 0.008). Consistently, significantly more HNPGLs with prior embolization were positive for HIF-2α (median nuclear HIF-2α positivity: 40%) as compared to HNPGLs without prior embolization (median nuclear HIF-2α positivity: 0%) (p = 0.016). Our results support the hypothesis that embolization with subsequent hypoxia leads to the upregulation of both PD-L1 and HIF-2α in HNPGLs, and could thus facilitate targeted treatment with HIF-2α and checkpoint inhibitors in the case of inoperable, locally advanced, or metastatic disease.

Improving the turnaround time of molecular profiling for advanced non-small cell lung cancer: Outcome of a new algorithm integrating multiple approaches

BACKGROUND

Molecular tumor profiling to identify oncogenic drivers and actionable mutations has a profound impact on how lung cancer is treated. Especially in the subgroup of non-small cell lung cancer (NSCLC), molecular testing for certain mutations is crucial in daily clinical practice and is recommended by international guidelines. To date, a standardized approach to identify druggable genetic alterations are lacking. We have developed and implemented a new diagnostic algorithm to harmonize the molecular testing of NSCLC.

PATIENTS AND METHODS

In this retrospective analysis, we reviewed 119 patients diagnosed with NSCLC at the University Hospital Zurich. Tumor samples were analyzed using our standardized diagnostic algorithm: After the histological diagnosis was made, tissue samples were further analyzed by immunohistochemical stainings as well as the real-time PCR test Idylla™. Extracted DNA was further utilized for comprehensive genomic profiling (FoundationOne®CDx, F1CDx).

RESULTS

Out of the 119 patients were included in this study, 100 patients were diagnosed with non-squamous NSCLC (nsqNSCLC) and 19 with squamous NSCLC (sqNSCLC). The samples from the nsqNSCLC patients underwent testing by Idylla™ and were evaluated by immunohistochemistry (IHC). F1CDx analysis was run on 67 samples and 46 potentially actionable genomic alterations were detected. Ten patients received the indicated targeted treatment. The median time to test results was 4 days for the Idylla test, 5 days for IHC and 13 days for the F1CDx.

CONCLUSION

In patients with NSCLC, the implementation of a standardized molecular testing algorithm provided information on predictive markers for NSCLC within a few working days. The implementation of broader genomic profiling led to the identification of actionable targets, which would otherwise not have been discovered.

NTRK Gene Fusions in Non-Small-Cell Lung Cancer: Real-World Screening Data of 1068 Unselected Patients

(1) Background: The main objectives of our study are (i) to determine the prevalence of NTRK (neurotrophic tyrosine kinase) fusions in a routine diagnostic setting in NSCLC (non-small cell lung cancer) and (ii) to investigate the feasibility of screening approaches including immunohistochemistry (IHC) as a first-line test accompanied by fluorescence in situ hybridization (FISH) and RNA-(ribonucleic acid-)based next-generation sequencing (RNA-NGS). (2) Methods: A total of 1068 unselected consecutive patients with NSCLC were screened in two scenarios, either with initial IHC followed by RNA-NGS (n = 973) or direct FISH testing (n = 95). (3) Results: One hundred and thirty-three patients (14.8%) were IHC positive; consecutive RNA-NGS testing revealed two patients (0.2%) with NTRK fusions (NTRK1-EPS15 (epidermal growth factor receptor pathway substrate 15) and NTRK1-SQSTM1 (sequestosome 1)). Positive RNA-NGS was confirmed by FISH, and NTRK-positive patients benefited from targeted treatment. All patients with direct FISH testing were negative. RNA-NGS- or FISH-positive results were mutually exclusive with alterations in EGFR (epidermal growth factor receptor), ALK (anaplastic lymphoma kinase), ROS1 (ROS proto-oncogene 1), BRAF (proto-oncogene B-Raf), RET (rearranged during transfection) or KRAS (kirsten rat sarcoma viral oncogene). Excluding patients with one of these alterations raised the prevalence of NTRK-fusion positivity among panTrk-(tropomyosin receptor kinase-) IHC positive samples to 30.5%. (4) Conclusions: NTRK fusion-positive lung cancers are exceedingly rare and account for less than 1% of patients in unselected all-comer populations. Both RNA-NGS and FISH are suitable to determine clinically relevant NTRK fusions in a real-world setting. We suggest including panTrk-IHC in a diagnostic workflow followed by RNA-NGS. Excluding patients with concurrent molecular alterations to EGFR/ALK/ROS1/BRAF/RET or KRAS might narrow the target population.

Role of Surgical Pathologist for Detection of Predictive Immuno-oncological Factors in Breast Cancer

Immune checkpoint inhibitors (ICIs) have changed therapy strategies in breast cancer (BC) patients suffering from triple-negative breast cancer (TNBC). For example, in Europe the anti-programmed cell death 1 ligand 1 (PD-L1) ICI Azetolizumab is approved for adult patients with locally advanced or metastasized TNBC (mTNBC), depending on the immunohistochemical (IHC) PD-L1 expression of immune cells in the tumor area [immune cell (IC) score ≥1%); the anti-programmed cell death 1 (PD-1) ICI pembrolizumab is approved for mTNBC if PD-L1 Combined Positive Score (CPS), that is PD-L1 expression on tumor and/or immune cells, is ≥10. For early TNBC, in contrast, neoadjuvant use of pembrolizumab is approved in the United States and Europe independent from PD-L1 IHC expression. The determination of PD-L1 expression in tumor tissue to predict response to ICI therapy requires sensitive immunostaining with appropriate primary antibodies and staining protocols and a standardized and meticulous assessment of PD-L1 IHC stained breast cancer tissue slides. For the selection of the test material and continuous quality control of the dyeing, high standards must be applied. The evaluation is carried out according to various evaluation algorithms (scores). Here, the role of PD-L1 in BC and the currently most relevant PD-L1 assays and scores for TNBC will be explained. Furthermore, other tissue-based biomarkers potentially predictive for ICI therapy response in BC, for example, tumor mutational burden (TMB), will be presented in this review.

Immune-Checkpoint-Inhibitor Therapy-Principles and Relevance of Biomarkers for Pathologists and Oncologists

Immune-checkpoint-inhibitor (ICI) therapy has been one of the major advances in the treatment of a variety of advanced or metastatic tumors in recent years. Therefore, ICI-therapy is already approved in first-line therapy for multiple tumors, either as monotherapy or as combination therapy. However, there are relevant differences in approval among different tumor entities, especially with respect to PD-L1 testing. Different response to ICI-therapy has been observed in the pivotal trials, so PD-L1 diagnostic testing is used for patient selection. In addition to PD-L1 testing of tumor tissue, liquid biopsy provides a noninvasive way to monitor disease in cancer patients and identify those who would benefit most from ICI-therapy. This overview focuses on the use of ICI-therapy and how it relates to common and potential future biomarkers for patient-directed treatment planning.

Synergic Induction of Autophagic Cell Death in Anaplastic Thyroid Carcinoma

Anaplastic thyroid carcinoma (ATC) has poor prognosis, high mortality rate and lack of effective therapy. A synergic combination of PD-L1 antibody together with cell death promoting substances like deacetylase inhibitors (DACi) and multi-kinase inhibitors (MKI) could sensitize ATC cells and promote decay by autophagic cell death. The PD-L1-inhibitor atezolizumab synergized with panobinostat (DACi) and sorafenib (MKI) leading to significant reduction of the viability, measured by real time luminescence, of three different patient-derived primary ATC cells, of C643 cells and follicular epithelial thyroid cells too. Solo administration of these compounds caused a significant over-expression of autophagy transcripts; meanwhile autophagy proteins were almost not detectable after the single administration of panobinostat, thus supporting a massive autophagy degradation process. Instead, the administration of atezolizumab caused an accumulation of autophagy proteins and the cleavage of the active caspases 8 and 3. Interestingly, only panobinostat and atezolizumab were able to exacerbate the autophagy process by increasing the synthesis, the maturation and final fusion with the lysosomes of the autophagosome vesicles. Despite ATC cells could be sensitized by atezolizumab via the cleavage of the caspases, no reduction of cell proliferation or promotion of cell death was observed. The apoptosis assay evidenced the ability of panobinostat alone and in combination with atezolizumab to induce the phosphatidil serine exposure (early apoptosis) and further the secondary necrosis. Instead, sorafenib was only able to cause necrosis. The increase of caspases activity induced by atezolizumab, the apoptosis and autophagy processes promoted by panobinostat synergize thus promoting cell death in well-established and primary anaplastic thyroid cancer cells. The combined therapy could represent a future clinical application for the treatment of such lethal and untreatable solid cancer.

Adenoid cystic carcinoma of the salivary glands: a pilot study of potential therapeutic targets and characterization of the immunological tumor environment and angiogenesis

BACKGROUND

Adenoid cystic carcinoma (ACC) is a rare type of cancer commonly occurring in salivary glands. It is characterized by slow but infiltrative growth, nerve infiltration and overall poor prognosis, with late recurrence and distant metastasis. The treatment of ACC is still limited to surgery and/or (adjuvant) radiotherapy. Till now no promising systemic therapy option exists. However, various studies deliver promising results after treatment with anti-angiogenetic agents, such as anti-EGFR-antibody Cetuximab or Tyrosinkinase inhibitor Lenvatinib.

METHODS

By using of immunohistological methods we analyzed and compared the macrophage and lymphocyte populations, vascularization, and PD-L1-status in 12 ACC of the salivary glands.

RESULTS

All cases showed a significant elevation of macrophages with M2 polarization and a higher vascularization in ACC compared to normal salivary gland tissue. The CD4/CD8 quotient was heterogenous. ACC does not show relevant PD-L1 expression.

CONCLUSIONS

The predominant M2 polarization of macrophages in ACC could be responsible for elevated vascularization, as already been proved in other cancer types, that M2 macrophages promote angiogenesis.

Anti-PD-(L)1 therapy of non-small cell lung cancer-A summary of clinical trials and current progresses

Background

This review discusses the impact of mono or combination therapy of immune checkpoint inhibitor (ICI) therapy in non-small cell lung cancer (NSCLC) patients, comparing clinical outcomes and safety. Cancer subtype, tumor mutational burden (TMB), programmed death-ligand 1 (PD-L1) expression state and T cell infiltration (TIL) density are considered for interpretations. Besides, current progresses in the field of immunotherapy are discussed.

Results

Anti-PD-(L)1 is a safe and an effective strategy in patients with advanced/metastatic NSCLC. Clinical responses to nivolumab and pembrolizumab, in particular, are promising. The most desired clinical responses are for patients receiving combination of anti-PD-(L)1 or anti-PD-(L)1/anti-cytotoxic T lymphocyte associated antigen-4 (CTLA-4) with chemotherapy (taxane and platinum). PD-L1 expression state (PD-L1 ≥ 50%), patient performance state (PS: 0-1 ECOG scale) and effector T cell (Teff) immune signature considerably affect ICI responses. Higher ICI responses are also expected in TMB ^high but EGFR^-/ALK^- cancer patients. In regard with safety profile, adverse events (AEs) related to anti-PD-(L)1 are lower compared with that for platinum-based and docetaxel therapy. Toripalimab is the safest among various immunotherapy drugs. Bispecific antibodies against anti-PD-(L)1 with dominant signaling or alternative checkpoints in tumor microenvironment (TME) is the current focus in immunotherapy of cancers like NSCLC. Besides, the contribution of extracellular vesicles (EVs) to immune escape and their implication in cancer diagnosis and therapy is on the eye of current investigations.

Conclusion

Appropriate biomarker selection will improve therapy outcomes in ICI treated NSCLC patients, particularly in cases under combinatory ICI therapy. Application of bispecific antibodies and EV-based targeted therapy are effective novel strategies to improve therapeutic outcomes in cancer patients.

Sarcopenia as a Determinant of the Efficacy of Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer: A Meta-Analysis

OBJECTIVE

The impact of pre-immunotherapy sarcopenia in patients with non-small cell lung cancer (NSCLC) receiving immune checkpoint inhibitors (ICIs) is elusive. We performed a meta-analysis to investigate the association between sarcopenia and clinical outcomes of ICIs.

METHODS

PubMed, EMBASE, and the Cochrane Library were searched.

RESULTS

Thirteen clinical trials were selected. The 1,2-year overall survival rate was lower in the sarcopenia group (odds ratio (OR) = 2.44, 95% confidence interval (CI), 1.78-3.35, P < 0.00001; OR = 1.60, 95% CI, 1.08-2.37, P = 0.02), with I² = 34%, P = 0.15, and I² = 41%, P = 0.12. The 1,2-year progression-free survival (PFS) was the same (OR = 3.43, 95% CI, 1.86-6.33, P < 0.0001; OR = 2.06, 95% CI, 1.19-3.58, P < 0.0001), with I² = 31%, P = 0.17 and I²=31%, P = 0.17. Sarcopenia reduced the overall response rate (OR = 2.22, 95% CI, 1.01-4.84, P = 0.02), with I²= 56%, P = 0.02, and disease control rate (OR = 3.15, 95% CI, 2.10-4.72, P < 0.0001) with I² = 33%, P = 0.18.

CONCLUSION

Pre-immunotherapy sarcopenia was associated with poor clinical outcomes in patients with advanced NSCLC who received ICIs.

The prognostic impact of the immune microenvironment in small-cell neuroendocrine carcinoma of the uterine cervix: PD-L1 and immune cell subtypes

Background

We investigate the correlation between programmed cell death-ligand 1 (PD-L1) and tumor-associated immune cell (TAIC) density in small-cell neuroendocrine carcinoma of the uterine cervix (SCNEC) and their correlation with clinicopathologic features.

Methods

PD-L1 and mismatch repair protein (MMR) expression in cancer cells and the density of TAIC were evaluated by immunohistochemistry in 89 SCNEC patients. The combined positive score (CPS), tumor proportion score (TPS), and immune cell score (ICS) of PD-L1 were measured, along with their correlation with clinicopathologic features in SCNEC patients using statistical analyses.

Results

CPS of PD-L1 ≥ 1 was seen in 68.5% of patients, positive TPS and ICS of PD-L1 were detected in 59.6% and 33.7% of patients, respectively. PD-L1CPS was higher in tumor-infiltrating immune cells (r = 0.387, p = 0.001) and positively correlated with programmed cell death-1 and forkhead box P3 + regulatory T cell (FOXP3 + Treg) infiltration (r = 0.443, p < 0.001; r = 0.532, p < 0.001). There was no statistical correlation between PD-L1 and MMR status. PD-L1CPS and PD-L1ICS positivity were independent prognostic factors, correlating with a favorable survival (HR (95%CI) = 0.363(0.139–0.950), p = 0.039 and HR (95% CI) = 0.199(0.050–0.802), p = 0.023, respectively). PD-L1ICS positivity was an independent indicator of recurrence in SCNEC patients and associated with better disease-free survival (HR (95% CI) = 0.124(0.036–0425), p = 0.001). TAIC and MMR levels had no statistical impact on survival results.

Conclusions

PD-L1 positivity was seen in over half of SCNEC tumors. It may work synergistically with FOXP3 + Treg and other infiltrating immune cells to support an adaptive immune response. PD-L1 positivity may be a favorable prognostic factor in SCNEC.

Recent progress and current challenges of immunotherapy in advanced/metastatic esophagogastric adenocarcinoma

The new era of immunotherapy is successfully implemented in the treatment of metastatic/locally advanced esophagogastric adenocarcinoma (EGAC), as it has been investigated in combinations with/without chemotherapy in human epidermal growth factor receptor 2 (Her2)-positive and Her2-negative tumors. Recent approvals of immune checkpoint inhibitors (ICI) enrich the therapeutic landscape in nearly every therapeutic line. Based on CHECKMATE-649, the combination of nivolumab and chemotherapy in first-line therapy of programmed cell death protein 1 (PD-L1)-positive patients with advanced gastroesophageal junction cancer (GEJC), esophageal cancer (EC), and gastric cancer (GC) was approved in Europe for PD-L1 combined positivity score (CPS) ≥ 5 patients and independently from PD-L1 score in the USA and Asia. Based on KEYNOTE-590, patients with advanced GEJC and EC qualify for the combination of pembrolizumab plus chemotherapy in Europe (CPS ≥ 10) and the USA. For Her2-positive patients, trastuzumab with first-line chemotherapy plus pembrolizumab has beneficial response rates and resulted in approval in the USA (KEYNOTE-811). In third-line therapy, superior overall survival (OS) was achieved by the administration of nivolumab (approval in Japan, ATTRACTION-02), and pembrolizumab shows a positive effect on the duration of response (KEYNOTE-059). Questions of resistance to immunotherapy or the role of gender in response to ICI need to be clarified. This review provides an overview of the current approvals of ICI in advanced EGAC and reflects results of relevant phase II/III trials with focus on possible biomarkers, including PD-L1 CPS and microsatellite-instability (MSI) status.

Cellular and soluble immune checkpoint signaling forms PD-L1 and PD-1 in renal tumor tissue and in blood

Immune checkpoint blockade therapy is a treatment option of various metastatic cancer diseases including renal cell carcinoma (RCC). Approved antibody drugs target the co-inhibitory signaling of Programmed Cell Death Ligand-1 (PD-L1) and its receptor Programmed Cell Death-1 (PD-1). The combined evaluation of PD-L1 and PD-1 at the mRNA and protein levels in tumor tissue with differentiation of tumor and immune cells as well as of soluble forms (sPD-L1) and (sPD-1) in blood is of basic interest in assessing biomarker surrogates. Here, we demonstrate that PD-L1 determined as fraction of stained tumor cells (TPS-score) correlates with PD-L1-mRNA in tumor tissue, reflecting the predominant expression of PD-L1 in tumor cells. Conversely, PD-1 in immune cells of tumor tissue (IC-score) correlated with PD-1-mRNA tissue levels reflecting the typical PD-1 expression in immune cells. Of note, sPD-L1 in blood did not correlate with either the TPS-score of PD-L1 or with PD-L1-mRNA in tumor tissue. sPD-L1 released into the supernatant of cultured RCC cells closely followed the cellular PD-L1 expression as tested by interferon γ (IFNG) induction and siRNA knockdown of PD-L1. Further analysis in patients revealed that sPD-L1 significantly increased in blood following renal tumor resection. In addition, sPD-L1 correlated significantly with inflammation marker C-reactive protein (CRP) and with PD-L1 mRNA level in whole blood. These results indicate that the major source of sPD-L1 in blood may be peripheral blood cells and not primarily tumor tissue PD-L1.

Frequency and Prognostic Significance of Intertumoural Heterogeneity in Multifocal Jejunoileal Neuroendocrine Tumours

BACKGROUND

A recent study found that multifocal jejunoileal neuroendocrine tumors (SI-NETs) are genetically unrelated synchronous neoplasms. So far, it is unclear if this finding of synchronous independent neoplasms is mirrored by heterogeneity of key morphological parameters of SI-NETs and how it affects patient survival.

METHODS

We separately assessed WHO grade (based on the Ki-67 index), expression of basal diagnostic markers (synaptophysin/chromogranin A/CDX2/serotonin), SSTR2a, and the contexture of the immunogenic microenvironment in 146 separate tumors from 28 patients with multifocal SI-NETs and correlated the results with clinicopathological factors and survival.

RESULTS

Synaptophysin and chromogranin A were strongly expressed in all tumors. WHO grade was concordant within all multifocal lesions in more than 80% of cases and the highest grade was usually found in the most advanced primary. Intertumoral expression of serotonin, SSTR2, and CDX2 was discrepant in 32%, 43%, and 50% of all patients, respectively. Neither heterogeneity of any of the aforementioned markers nor multifocality itself had any impact on patient survival (p = n.s.).

DISCUSSION

Multifocal SI-NET show considerable variability in some of the central diagnostic parameters. However, neither intertumoral heterogeneity of those parameters nor multifocality itself had any impact on patient survival, showing that extensive testing of all multifocal lesions is not necessarily required.

The expression of the adenosine pathway markers CD39 and CD73 in salivary gland carcinomas harbors the potential for novel immune checkpoint inhibition

BACKGROUND

In salivary gland carcinomas (SGC), there is only a small fraction of entities that appears to profit from immune checkpoint inhibition (ICI). Recent findings connected the activation of adenosine-signaling with a tolerogenic microenvironment. Therefore, the inhibition of adenosine pathway markers (CD39 and/or CD73) can augment ICI and/or display a novel immunotherapeutic strategy beyond ICI. Here, we assessed the immuno-histochemical expression of CD39 and CD73 across a wide spectrum of SGCs.

METHODS

In total, 114 patients with SGCs consecutively diagnosed between 2001 and 2021 were assessed for clinicopathological baseline characteristics and underwent confirmatory histopathological review. Immunohistochemical expression levels of CD39 and CD73 were assessed by applying the tumor proportion score (TPS) and the immune proportional score (IPS) comparable to PD-L1 expression analysis in routine clinical practice. Additionally, findings were correlated with PD-L1 expression levels.

RESULTS

The median age was 60.6 and 51.8% patients were female. The cohort covered a spectrum of eight distinct entities. Advanced-stage disease (UICC/AJCC III/IVA-IVC) at initial diagnosis was present in the majority of patients (64/114). Immunohistochemical staining revealed positivity for CD39 and CD73 in 48.2% and 21.1% on tumor cells (TPS ≥ 1%) as well as 46.4% and 42.9% within the immune cell infiltrate (IPS ≥ 1%), respectively. Further comparative analyses revealed immune-cold entities such adenoid cystic carcinoma (AdCC), immune-hot tumors such as adenocarcinoma, not otherwise specified (AC (NOS)) and entities with intermediate immunologic features such as acinic cell carcinoma (ACC).

CONCLUSION

Current results indicate entity-specific adenosine signaling signatures. These findings suggest that the adenosine pathway plays a decisive role in tumor immunity among the major spectrum of SGCs. Targeting the adenosine pathway might pose a promising therapeutic option for selected entities.

Standardized 18F-FDG PET/CT radiomic features provide information on PD-L1 expression status in treatment-naïve patients with non-small cell lung cancer

PURPOSE

To study the relationship between standardized 18F-FDG PET/CT radiomic features and clinicopathological variables and programmed death ligand-1 (PD-L1) expression status in non-small cell lung cancer (NSCLC) patients.

METHODS

58 NSCLC patients with preoperative 18F-FDG PET/CT scans and postoperative results of PD-L1 expression were retrospectively analysed. A standardized, open-source software was used to extract 86 radiomic features from PET and low-dose CT images. Univariate analysis and multivariate logistic regression were used to find independent predictors of PD-L1 expression. The Area Under the Curve (AUC) of receiver operating characteristic (ROC) curve was used to compare the ability of variables and their combination in predicting PD-L1 expression.

RESULTS

Multivariate logistic regression resulted in the PET radiomic feature GLRLM_LGRE (Odds Rate (OR): 0.300 vs 0.114, 95% confidence interval (CI): 0.096-0.931 vs 0.021-0.616, in NSCLC and adenocarcinoma respectively) and the CT radiomic feature GLZLM_SZE (OR: 3.338 vs 7.504, 95%CI: 1.074-10.375 vs 1.382-40.755, in NSCLC and adenocarcinoma respectively), being independent predictors of PD-L1 status. In NSCLC group, after adjusting for gender and histology, the PET radiomic feature GLRLM_LGRE (OR: 0.282, 95%CI: 0.085-0.936) remained an independent predictor for PD-L1 status. In the adenocarcinoma group, when adjusting for gender the PET radiomic feature GLRLM_LGRE (OR: 0.115, 95%CI: 0.021-0.631) and the CT radiomic feature GLZLM_SZE (OR: 7.343, 95%CI: 1.285-41.965) remained associated with PD-L1 expression.

CONCLUSION

NSCLC and adenocarcinoma with PD-L1 expression show higher tumour heterogeneity. Heterogeneity-related 18F-FDG PET and CT radiomic features showed good ability to non-invasively predict PD-L1 expression.

Identification of New Prognostic Markers and Therapeutic Targets for Non-Muscle Invasive Bladder Cancer: HER2 as a Potential Target Antigen

Bacillus Calmette–Guérin (BCG) is the gold standard adjuvant treatment for non-muscle-invasive bladder cancer (NMIBC). However, given the current global shortage of BCG, new treatments are needed. We evaluated tumor microenvironment markers as potential BCG alternatives for NMIBC treatment. Programmed death-ligand 1, human epidermal growth factor receptor-2 (HER2), programmed cell death-1 (PD1), CD8, and Ki67 levels were measured in treatment-naïve NMIBC and MIBC patients (pTa, pT1, and pT2 stages). Univariate and multivariate Cox proportional hazard models were used to determine the impact of these markers and other clinicopathological factors on survival, recurrence, and progression. EP263, IM142, PD1, and Ki67 levels were the highest in the T2 stage, followed by the T1 and Ta stages. HER2 and IM263 expressions were higher in the T1 and T2 stages than in the Ta stage. In NMIBC, the significant prognostic factors for recurrence-free survival were adjuvant therapy, tumor grade, and HER2 positivity, whereas those for progression-free survival included age, T-stage, and IM263. Age, T-stage, EP263, PD1, CD8, and Ki67 levels were significant factors associated with overall survival. IM263 and HER2 are potential biomarkers for progression and recurrence, respectively. Therefore, we propose HER2 as a potential target antigen for intravesical therapeutics as a BCG alternative.

Tislelizumab combined with chemotherapy as neoadjuvant therapy for surgically resectable esophageal cancer: A prospective, single-arm, phase II study (TD-NICE)

BACKGROUND

Clinical benefit of neoadjuvant immunotherapy in resectable esophageal squamous cell carcinoma (ESCC). remains unclear. This study evaluated the efficacy and safety of the programmed death 1 (PD-1) inhibitor tislelizumab combined with chemotherapy as neoadjuvant therapy in patients with resectable ESCC.

METHODS

Treatment-naïve patients were enrolled and eligible patients received 3 cycles of neoadjuvant therapy with tislelizumab, carboplatin, and nab-paclitaxel. The primary endpoint was surgery patients major pathological response (MPR). Subgroup analysis was stratified by tumor downstaging, circumferential resection margin (CRM), PD-ligand 1 (PD-L1) expression, and tumor mutation burden (TMB). Safety was assessed by adverse events (AEs) and postoperative complications.

RESULTS

Between September 2020 and March 2021, 45 patients were enrolled. Thirty-six (80.0%) of 45 patients underwent surgery, and 29 (80.5%) underwent successful R0 resection. MPR and pathological complete response (pCR) for surgery patients were 72.0% and 50.0%, respectively. Intention to treatment (ITT) patients MPR and PCR were 57.5% and 40%. Downgrading occurred in 75% of 36 patients. MPR and pCR were identified to be associated with tumor downstaging and CRM but not PD-L1 expression or TMB. TPS levels in MPR and pCR group were significantly higher than that in Non-MPR and Non-pCR group, respectively. Treatment-related AEs of grade 3-4 and immune-related AEs occurred in 42.2% and 22.2% of 45 patients, respectively, and postoperative complications occurred in 77.8% of 36 patients. No treatment-related surgical delay or death occurred. No associations between gene mutation and pathological efficacy were observed.

CONCLUSIONS

Tislelizumab plus chemotherapy as neoadjuvant therapy demonstrates promising antitumor activity for resectable ESCC with high rates of MPR, pCR, and R0 resection, as well as acceptable tolerability.

Decision Support for Oropharyngeal Cancer Patients Based on Data-Driven Similarity Metrics for Medical Case Comparison

Making complex medical decisions is becoming an increasingly challenging task due to the growing amount of available evidence to consider and the higher demand for personalized treatment and patient care. IT systems for the provision of clinical decision support (CDS) can provide sustainable relief if decisions are automatically evaluated and processed. In this paper, we propose an approach for quantifying similarity between new and previously recorded medical cases to enable significant knowledge transfer for reasoning tasks on a patient-level. Methodologically, 102 medical cases with oropharyngeal carcinoma were analyzed retrospectively. Based on independent disease characteristics, patient-specific data vectors including relevant information entities for primary and adjuvant treatment decisions were created. Utilizing the ϕK correlation coefficient as the methodological foundation of our approach, we were able to determine the predictive impact of each characteristic, thus enabling significant reduction of the feature space to allow for further analysis of the intra-variable distances between the respective feature states. The results revealed a significant feature-space reduction from initially 19 down to only 6 diagnostic variables (ϕK correlation coefficient ≥ 0.3, ϕK significance test ≥ 2.5) for the primary and 7 variables (from initially 14) for the adjuvant treatment setting. Further investigation on the resulting characteristics showed a non-linear behavior in relation to the corresponding distances on intra-variable level. Through the implementation of a 10-fold cross-validation procedure, we were further able to identify 8 (primary treatment) matching cases with an evaluation score of 1.0 and 9 (adjuvant treatment) matching cases with an evaluation score of 0.957 based on their shared treatment procedure as the endpoint for similarity definition. Based on those promising results, we conclude that our proposed method for using data-driven similarity measures for application in medical decision-making is able to offer valuable assistance for physicians. Furthermore, we consider our approach as universal in regard to other clinical use-cases, which would allow for an easy-to-implement adaptation for a range of further medical decision-making scenarios.

Cancer cachexia as a determinant of efficacy of first-line pembrolizumab in patients with advanced non-small cell lung cancer

Pembrolizumab, either as a type of monotherapy or in combination with cytotoxic anticancer agents, is effective in the treatment of advanced non-small cell lung cancer (NSCLC). However, the development of cancer cachexia may adversely affect anticancer drug therapy. The present study investigated the effect of cancer cachexia on clinical outcomes in patients with advanced NSCLC who received first-line pembrolizumab. The data of patients with advanced NSCLC receiving first-line monotherapy or combination therapy with pembrolizumab were retrospectively analyzed. The primary endpoint was time to treatment failure (TTF), and the secondary endpoints were overall survival (OS) and incidence of adverse events (AEs). Clinical outcome was compared between patients with and without cancer cachexia. A total of 53 patients were analyzed. Among all patients, median TTF and OS were significantly shorter in patients with cancer cachexia than in those without [TTF: 5.8 vs. 10 months; hazard ratio (HR): 2.13; 95% confidence interval (CI): 1.07-4.24; P=0.016; OS: 12.1 months vs. not reached; HR: 5.85; 95% CI: 2.0-17.1; P=0.001]. In addition, TTF in the pembrolizumab monotherapy group was significantly shorter in patients with cancer cachexia than in those without, but no significant difference was detected in patients receiving pembrolizumab combination therapy. The incidence of AEs did not significantly differ between patients with and without cancer cachexia, except with regard to hypothyroidism. In conclusion, although cancer cachexia is prognostic of a poor outcome in patients with advanced NSCLC who receive first-line pembrolizumab, cancer cachexia might not affect therapeutic efficacy in combination therapy with pembrolizumab and cytotoxic anticancer agents.

Analysis of PD-1, PD-L1, and T-cell infiltration in angiosarcoma pathogenetic subgroups

Angiosarcoma (AS) is a rare malignancy with a poor prognosis. It can develop spontaneously or due to previous radiotherapy (RT), ultraviolet (UV) radiation, or lymphoedema (Stewart Treves AS). Novel therapeutic approaches are needed, but progress is hindered because of the heterogeneity and rarity of AS. In order to explore the potential of immune checkpoint inhibition (ICI), we investigated the protein expression of programmed cell death 1 (PD-1), programmed death-ligand 1 (PD-L1), and CD8 + T cells in 165 AS cases in relation to AS subgroups based on clinical classification and in relation to whole-genome methylation profiling based clusters (A1, A2, B1, B2). High PD-L1 and PD-1 expression were predominantly shown in UV-associated, visceral, and soft tissue AS. RT-associated AS showed predominantly high PD-1 expression. CD8 + T cell infiltration was present in the majority of AS samples. Within the UV-associated AS, two different clusters can be distinguished by DNA methylation profiling. Cases in cluster A1 showed higher PD-1 (p = 0.015), PD-L1 (p = 0.015), and CD8 + T cells (p = 0.008) compared to those in cluster B2, suggesting that these UV-AS tumors are more immunogenic than B2 tumors showing a difference even within one subgroup. In soft tissue AS, combined PD-1 and PD-L1 expression showed a trend toward poor survival (p = 0.051), whereas in UV-associated AS, PD-1 expression correlated with better survival (p = 0.035). In conclusion, we show the presence of PD-1, PD-L1, and CD8 + T cells in the majority of AS but reveal differences between and within AS subgroups, providing prognostic information and indicating to be predictive for ICI.

Mutational and immunologic Landscape in malignant Salivary Gland Tumors harbor the potential for novel therapeutic strategies

Salivary gland carcinomas (SGC) are rare (3-6 % of all head and neck cancers) and show biological heterogeneity depending on the respective histological subtype. While complete surgical resection is the standard treatment for localized disease, chemotherapy or radiation therapy are frequently insufficient for the treatment of unresectable or metastasized SGC. Therefore, new therapeutic approaches such as molecularly targeted therapy or the application of immune checkpoint inhibition enhance the treatment repertoire. Accordingly, comprehensive analyses of the genomic landscape and the tumor-microenvironment (TME) are of crucial importance in order to optimize and individualize SGC treatment. This manuscript combines the current scientific knowledge of the composition of the mutational landscape and the TME in SGCs harboring the potential for novel (immune-) targeted therapeutic strategies.

Programmed Death-Ligand 1 (PD-L1) as Immunotherapy Biomarker in Breast Cancer

Breast cancer constitutes the most common malignant neoplasm in women around the world. Approximately 12% of patients are diagnosed with metastatic stage, and between 5 and 30% of early or locally advanced BC patients will relapse, making it an incurable disease. PD-L1 ligation is an immune inhibitory molecule of the activation of T cells, playing a relevant role in numerous types of malignant tumors, including BC. The objective of the present review is to analyze the role of PD-L1 as a biomarker in the different BC subtypes, adding clinical trials with immune checkpoint inhibitors and their applicable results. Diverse trials using immunotherapy with anti-PD-1/PD-L1 in BC, as well as prospective or retrospective cohort studies about PD-L1 in BC, were included. Despite divergent results in the reviewed studies, PD-L1 seems to be correlated with worse prognosis in the hormone receptor positive subtype. Immune checkpoints inhibitors targeting the PD-1/PD-L1 axis have achieved great response rates in TNBC patients, especially in combination with chemotherapy, making immunotherapy a new treatment option in this scenario. However, the utility of PD-L1 as a predictive biomarker in the rest of BC subtypes remains unclear. In addition, predictive differences have been found in response to immunotherapy depending on the stage of the tumor disease. Therefore, a better understanding of tumor microenvironment, as well as identifying new potential biomarkers or combined index scores, is necessary in order to make a better selection of the subgroups of BC patients who will derive benefit from immune checkpoint inhibitors.

Multiple Immunostainings with Different Epitope Retrievals—The FOLGAS Protocol

We describe a sequential multistaining protocol for immunohistochemistry, immunofluorescence and CyTOF imaging for formalin-fixed, paraffin-embedded specimens (FFPE) in the formalin gas-phase (FOLGAS), enabling sequential multistaining, independent from the primary and secondary antibodies and retrieval. Histomorphologic details are preserved, and crossreactivity and loss of signal intensity are not detectable. Combined with a DAB-based hydrophobic masking of metal-labeled primary antibodies, FOLGAS allows the extended use of CyTOF imaging in FFPE sections.

Head and neck cancer

Head and neck cancer is the seventh most common type of cancer worldwide and comprise of a diverse group of tumours affecting the upper aerodigestive tract. Although many different histologies exist, the most common is squamous cell carcinoma. Predominant risk factors include tobacco use, alcohol abuse, and oncogenic viruses, including human papillomavirus and Epstein-Barr virus. Head and neck malignancies remain challenging to treat, requiring a multidisciplinary approach, with surgery, radiotherapy, and systemic therapy serving as key components of the treatment of locally advanced disease. Although many treatment principles overlap, treatment is generally site-specific and histology-specific. This Seminar outlines the current understanding of head and neck cancer and focuses on treatment principles, while also discussing future directions to improve the outcomes of patients with these malignancies.

The Challenge to the Pathologist of PD-L1 Expression in Tumor Cells of Non-Small-Cell Lung Cancer—An Overview

In recent years, the treatment of non-small-cell lung cancer (NSCLC) has been fundamentally changed by immunotherapy where the immune system is reactivated using anti-programmed cell death protein 1/programmed death ligand 1 (PD1/PD-L1) checkpoint inhibition. With this, the immunohistological detection of PD-L1 has become one of the most important predictive biomarkers, leading pathologists to play a central role in the immuno-oncological therapy decisions. This has brought them the challenge of requiring the knowledge of relevant checkpoint inhibitors (CI), different PD-L1 scores and cut-offs as well as the choice of the right tissues and controls. Their involvement is also required in the careful validation of both clinical trial assays (CTAs) and laboratory developed tests (LDTs), in addition to the internal and external quality assessment and the interpretation and scoring of the staining based on specialist training. After the training of tumor proportion score (TPS) scoring in NSCLC, pathologists show a high level of concordance, with some variation between different cut-offs. Since not all patients benefit from immunotherapy, further research is needed to validate new predictive markers and optimize existing ones. In this context, these studies focus on a combination of PD-L1 and molecular signatures.

The prevalence of DNA microsatellite instability in anaplastic thyroid carcinoma - systematic review and discussion of current therapeutic options

INTRODUCTION

Anaplastic thyroid carcinoma is a rare, rapidly progressing, highly aggressive thyroid malignancy. Responses to immune checkpoint inhibitors in mismatch repair-deficient/microsatellite instability-high tumours of other locations have shown promising results, and with the extended approval of the PD-1 receptor inhibitor pembrolizumab by the Food and Drug Administration, also anaplastic thyroid cancer (ATC) requires analysis for microsatellite instability (MSI) status.

MATERIAL AND METHODS

Systematic research for relevant literature was conducted in different databases. Prevalence, detection methods, and the potential prognostic/predictive value of MSI in view of the available targeted therapies were of special focus.

RESULTS

Selected citations revealed the prevalence of MSI in 7.4%, with mutations in the MSH2 gene (33%) being the most frequent, followed by MSH6 (25%) and MLH1 (16.7%) occurring in the following combinations: MLH1-MSH2 (8.3%), MSH2-MSH6 (8.3%), and MLH3-MSH5 (8.3%). No mutations in the PMS2 gene were reported. Sixty-six co-mutations in 9 cases were found, with TP53 (88.9%), NF1 (44.4 %), ATM (33.3%), and RB1 (33.3%) being the most frequent. No RAS mutations were noted. Survival ranged between 2.8 and 48 months, and patient age varied between 49 and 84 years. There are insufficient and heterogenous data concerning the predictive or prognostic value of mismatch repair-deficient/microsatellite instability status.

CONCLUSIONS

Tumour molecular profiling is fundamental in ATC for predictive, prognostic, as well as therapeutic reasons, and analysis of MSI status is strongly suggested because a small subgroup show the MSI signature and might profit from recently approved targeted therapies.

Shifting Gears in Precision Oncology-Challenges and Opportunities of Integrative Data Analysis

For decades, research relating to modification of host immunity towards antitumor response activation has been ongoing, with the breakthrough discovery of immune-checkpoint blockers. Several biomarkers with potential predictive value have been reported in recent studies for these novel therapies. However, with the plethora of therapeutic options existing for a given cancer entity, modern oncology is now being confronted with multifactorial interpretation to devise “the best therapy” for the individual patient. Into the bargain come the multiverse guidelines for established and emerging diagnostic biomarkers, as well as the complex interplay between cancer cells and tumor microenvironment, provoking immense challenges in the therapy decision-making process. Through this review, we present various molecular diagnostic modalities and techniques, such as genomics, immunohistochemistry and quantitative image analysis, which have the potential of becoming powerful tools in the development of an optimal treatment regime when analogized with patient characteristics. We will summarize the underlying complexities of these methods and shed light upon the necessary considerations and requirements for data integration. It is our hope to provide compelling evidence to emphasize on the need for inclusion of integrative data analysis in modern cancer therapy, and thereupon paving a path towards precision medicine and better patient outcomes.

The peri- and intratumoral immune cell infiltrate and PD-L1 status in invasive squamous cell carcinomas of the penis

INTRODUCTION

Penile carcinomas are rare tumors throughout Europe. Therefore, little attention is drawn to this disease. That makes it important to study tumor-associated key metrics and relate these to known data on penile neoplasias.

MATERIALS AND METHODS

A cohort of 60 well-defined penile invasive carcinomas with known human papillomavirus (HPV) infection status was investigated. Data on tumor type, grading and staging were recorded. Additionally, data on the peri- and intratumoral immune cell infiltrate in a semiquanititave manner applying an HE stain were assessed.

RESULTS

Our study showed a significant correlation of immune cell infiltrate and pT stage with overall survival. Therefore, in a subset of tumors, PD-L1 staining was applied. For tumor proportion score (TPS), 26 of 30 samples (87%) were scored >0%. For the immune cell score (IC), 28 of 30 samples (93%) were defined as >0% and for CPS, 29 of 30 samples (97%) scored >0. PD-L1 expression was not associated with overall survival.

CONCLUSION

PD-L1 is expressed in penile carcinomas, providing a rationale for targeted therapy with checkpoint inhibitors. We were able to show that immune reaction appears to be prognostically relevant. These data enhance the need for further studies on the immune cell infiltrate in penile neoplasias and show that PD-L1 expression is existent in our cohort, which may be a potential target for checkpoint inhibitor therapy.

Pan-Cancer Biomarkers: Changing the Landscape of Molecular Testing

CONTEXT.—

The increasing use of large panel next-generation sequencing technologies in clinical settings has facilitated the identification of pan-cancer biomarkers, which can be diagnostic, prognostic, predictive, or most importantly, actionable.

OBJECTIVE.—

To discuss recently approved and emerging pan-cancer and multihistology biomarkers as well as testing methodologies.

DATA SOURCES.—

The US Food and Drug Administration approval documents, National Comprehensive Cancer Network guidelines, literature, and authors' own publications.

CONCLUSIONS.—

Since 2017, the US Food and Drug Administration has approved genotype-directed therapies for pan-cancer biomarkers, including microsatellite instability, neurotrophic receptor kinases fusions, and high-tumor mutation burden. Both the importance and rarity of these biomarkers have increased the prevalence of genomic profiling across solid malignancies. As an integral part of the management team of patients with advanced cancer, pathologists need to be aware of these emerging biomarkers, the therapies for which they determine eligibility, and the strengths and pitfalls of the available clinical assays.

PD-L1 expression in bladder cancer: Which scoring algorithm in what tissue?

INTRODUCTION

For cisplatin-ineligible patients, approval of first-line immune-checkpoint inhibitor therapy relies on the programmed death ligand 1 (PD-L1) expression assay employed, namely, the combined positive score (CPS) or immune cell (IC) score. This study compares PD-L1 diagnostic scores and positivity in primary and matched metastatic bladder cancer tissue.

METHODS

A total of 108 patients undergoing radical cystectomy for urothelial bladder cancer and lymphatic spread (pN+) were included. PD-L1 expression was compared by immunohistochemistry (IHC) between the primary bladder tumor and associated lymph node metastases using Ventana SP263 anti-PD-L1 antibody. In a subset of cases further IHC was performed with Ventana SP142 and Dako 22C3 antibodies. Second, the PD-L1 scoring algorithms for the CPS and IC score were compared. Correlation of PD-L1 positivity with clinical parameters and tumor stage was assessed. Intra- and intertissue analyses were performed with Pearson's chi square test, McNemar test and Spearman correlation employing IBM SPSS 25.

RESULTS

PD-L1 expression did not correlate with clinicopathological parameters. The CPS (43.5% vs. 35.6%; P=0.006) and the IC score (28.7% vs. 21.2%; P=0.002) yielded PD-L1 positivity significantly more often in primary BC than in matched lymph node metastasis. Both the CPS (r=0.775; P<0.001) and the IC score (r=0.711; P<0.001) correlated between primary and metastatic bladder cancer tissue. Employing CPS vs. IC led to significantly more PD-L1-positive classified cases in primary BC (CPS vs. IC; 43.5% vs. 28.7%; P<0.001) and lymph node metastasis (CPS vs. IC; 35.6% vs. 21.2%, P<0.001).

CONCLUSION

Compared to lymph node analysis, bladder tissue yields more PD-L1 positivity assessed with the CPS and IC scores. This is particularly evident when employing the CPS. The findings highlight that employing both PD-L1 assays may maximize eligibility for first-line checkpoint-inhibitors to treat bladder cancer patients unfit for cisplatin-based chemotherapy.

Comparison of PD-L1 Scores in Primary Kidney Tumors Versus Accompanying Venous Tumor Thrombi: Retrospective, Comparative, Monocentric Study in Treatment-Naive Patients

Introduction

Renal cell carcinoma (RCC), an immunogenic tumor, is the most common form of kidney cancer worldwide. Immune checkpoint inhibitors (ICIs) play an important role in the treatment of metastatic RCC. Programmed death-ligand (PD-L1) has already been proposed as a possible prognosticator for ICIs effectiveness. To elucidate the feasible role of ICIs in neoadjuvant settings, we have assessed the most common PD-L1 expression modalities [tumor proportion score (TPS), combined positivity score (CPS) and inflammatory cell (IC) score] in primary tumors (PTs) and venous tumor thrombi (VTT) in first diagnosed, previously untreated RCC patients with accompanying VTT.

Methods

Between January 1999 and December 2016, 71 patients with a first diagnosed, untreated, locally advanced RCC (aRCC) (≥ pT3a) underwent surgery in Hanover Medical School (MHH). PD-L1 expression was examined separately in PTs and VTT using the CPS, IC score and TPS. We also considered the age at the time of the initial surgery and gender as probable influencing factors. By using a cutoff value of 1 (1%), PD-L1 expression levels in PTs and VTT were assessed to enable the determination of any frequency differences.

Results

Positive scores for PTs were shown by 54 (CPS), 53 (IC score) and 34 (TPS) patients, whereas in VTT, positive scores were evaluated for a total of 50 (CPS), 47 (IC-score) and 36 (TPS) patients. No statistically significant differences were obtained between the PD-L1 expression immunoscores for PTs and VTT. The covariates age at the time of the initial surgery and gender could not be statistically proven to influence the differences in PD-L1 expression between the VTT and PTs.

Conclusion

To the best of our knowledge, this research is the largest study to investigate PD-L1 expression in PTs and VTT in 71 cases. It could have relevance for the future development of neoadjuvant immunotherapy options, particularly in aRCC with VTT.

[Predictive diagnostics for checkpoint inhibitors]

Checkpoint inhibitors have revolutionized oncological treatment in many cancers and added a new immuno-oncological treatment pillar to the medicinal arsenal of conventional and molecularly targeted therapies. In monotherapy and in combination therapies, however, not all patients respond equally well, even in generally responsive tumor entities. Therefore, since the introduction of these therapies, a major focus has been the research on and implementation of predictive markers for patient selection. The first established biomarker, the expression of the target molecule PD-L1, has found its way into routine diagnostics in a large number of unfortunately very divergent diagnostic constellations in multiple entities. In addition, some molecular predictors, including the measurement of microsatellite instability and tumor mutational burden, have also been suggested and in some cases are already implemented into routine diagnostics. Additional molecular parameters have been proposed but most of them have not yet found their way into routine patient care. This review article discusses the current status and recent developments in the field of diagnostic response predictors in the context of an immune checkpoint blockade.

PPARγ induces PD-L1 expression in MSS+ colorectal cancer cells

Only a small subset of colorectal cancer (CRC) patients benefits from immunotherapies, comprising blocking antibodies (Abs) against checkpoint receptor "programmed-cell-death-1" (PD1) and its ligand (PD-L1), because most cases lack the required mutational burden and neo-antigen load caused by microsatellite instability (MSI) and/or an inflamed, immune cell-infiltrated PD-L1+ tumor microenvironment. Peroxisome proliferator-activated-receptor-gamma (PPARγ), a metabolic transcription factor stimulated by anti-diabetic drugs, has been previously implicated in pre/clinical responses to immunotherapy. We therefore raised the hypothesis that PPARγ induces PD-L1 on microsatellite stable (MSS) tumor cells to enhance Ab-target engagement and responsiveness to PD-L1 blockage. We found that PPARγ-agonists upregulate PD-L1 mRNA/protein expression in human gastrointestinal cancer cell lines and MSS+ patient-derived tumor organoids (PDOs). Mechanistically, PPARγ bound to and activated DNA-motifs similar to cognate PPARγ-responsive-elements (PPREs) in the proximal -2 kb promoter of the human PD-L1 gene. PPARγ-agonist reduced proliferation and viability of tumor cells in co-cultures with PD-L1 blocking Ab and lymphokine-activated killer cells (LAK) derived from the peripheral blood of CRC patients or healthy donors. Thus, metabolic modifiers improved the antitumoral response of immune checkpoint Ab, proposing novel therapeutic strategies for CRC.

Programmed Death Ligand-1 (PD-L1) Is an Independent Negative Prognosticator in Western-World Gallbladder Cancer

Inhibition of the programmed cell death protein-1/ligand-1 (PD-1/PD-L1) axis has opened a new era in the treatment of solid cancers. However, there is no data on the expression and relevance of PD-L1 in Western gallbladder cancer (GBC). We assessed PD-L1 immunohistochemically in 131 GBC patients as Tumor Proportion Score (TPS), Immune Cell Score (IC) and Combined Positivity Score (CPS). Tumor cells expressed PD-L1 in a subset of 14.7% GBC patients at a TPS cut-off of 1%. Higher PD-L1 levels above 10% and 25% TPS were reached in 4.7% and 3.1% of GBC cases, respectively. At a 10% cut-off, TPS was associated with distinct histomorphological subtypes and correlated with poor tumor differentiation. Survival analysis revealed a TPS above 10% to be a highly significant and independent negative prognosticator in GBC. PD-L1 expression was associated with increased CD4+, CD8+ and PD-1+ immune cell densities. In 14.8% of the cases, scattered immune cells expressed T-cell immunoreceptor with Ig and ITIM domains (TIGIT), which was correlated to tumoral expression of its ligand CD155. We here show that a high PD-L1 expression confers a negative prognostic value in Western-world GBC and highlight the TIGIT/CD155 immune checkpoint as a potential new target for GBC immunotherapy.