High PD-L1 Expression Research Articles

Landscape of MET genomic alterations in colorectal cancer (CRC).

247 Background: MET signaling is implicated in the tumorigenesis of many solid tumors, including CRC. MET-targeted therapies are approved in non-small cell lung cancer with novel agents in clinical trials for tumors with MET exon 14 splice site mutations, MET amplifications, and recently MET expression. There is emerging therapeutic interest in targeting MET in CRC. Methods: Tumor samples from 50,500 cases of clinically advanced CRC were analyzed by hybrid capture-based comprehensive genomic profiling (CGP) that evaluated all classes of genomic alterations (GA). MSI-high status, tumor mutational burden (TMB), genomic ancestry, trinucleotide mutational signatures, and homologous recombination deficiency signature (HRDsig) were assessed for patients with activating MET GA. PD-L1 expression was determined by IHC (Dako 22C3 with TPS scoring system). Results were compared using the Fisher exact test with the Benjamini-Hochberg adjustment. Results: A total of 502 (1.0%) cases of activating GA of MET (METmut) were identified, including 418 cases (0.83%) with MET amplification (METamp), 10 (<0.1%) rearrangements, and 78 (0.1%) short variant (SV) mutations with 19 (<0.1%) cases of MET exon 14 splice site mutations. When compared with MET wild-type (METwt) CRC, the METmut CRC were of similar age (median 62 years), and numerically more likely to be male (61.4% vs 56.0%; P=.05). There were no differences in genomic ancestry (72% European ancestry for both groups). The METmut CRC featured more cases with a POLE signature (3.6% vs 0.4%; P=<0.0001) and more GA per tumor (7 vs 5; P<0.0001). MSI-high status was similar in both groups, with 4.2% in METmut and 6.0% in METwt (P=0.28). TMB levels were numerically higher in the METmut cases (TMB ≥ 10 mutations/Mb at 12.2% vs 9.0%; P=0.058). Low level PD-L1 expression (1-49% TPS) was similar in both groups (13.9% in METmut vs 13.3% in METwt), and while not statistically significant, high level PD-L1 expression (>50% TPS) was higher in the METmut group (4.3% vs 1.6%; P=0.056). The frequencies of HRDsig+ CRC were rare and similar in both groups with 1.5% in METmut and 1.7% in METwt. METmut CRC had lower frequencies of GA in KRAS (34.7% vs 48.8%; P<0.0001), NRAS (1.8% vs 4.2%; P=0.011), APC (72.5% vs 78.2%; P=0.009) and PIK3CA (12.2% vs 18.9%; P=0.0004), and higher frequencies of GA in CDK6 (10.2% vs 0.6%; P<0.0001), EGFR (5.2% vs 0.2%; P=0.0002), ERBB2 (9.6% vs 5.2%; P=0.0004), HGF (8.0% vs 0.8%; P<0.0001), POLE (4.2% vs 0.5%; P=0.005) and TP53 (84.1% vs 75.9%; P<0.0001). In METmut CRC, ERBB2 alterations were 4.1% amplifications, 2.9% sequence mutations, 0.9% with more than one mutation. BRAF V600E was seen in 5.9% in METmut CRC and 8.4% of METwt. Conclusions: CGP reveals significant differences in the genomic landscapes of METmut CRC and METwt CRC, which may guide selection of potential rational drug combinations with novel MET-targeted therapies.

A Mitochondria-Related Signature in Diffuse Large B-Cell Lymphoma: Prognosis, Immune and Therapeutic Features.

Distinctive heterogeneity characterizes diffuse large B-cell lymphoma (DLBCL), one of the most frequent types of non-Hodgkin's lymphoma. Mitochondria have been demonstrated to be closely involved in tumorigenesis and progression, particularly in DLBCL. The purposes of this study were to identify the prognostic mitochondria-related genes (MRGs) in DLBCL, and to develop a risk model based on MRGs and machine learning algorithms. Transcriptome profiles and clinical information were obtained from the Gene Expression Omnibus (GEO) database. The risk model was defined using Least Absolute Shrinkage and Selection Operator (Lasso) regression algorithm, and its prognostic value was further examined in independent datasets. Patients were stratified into two clusters based on the risk scores, additionally a nomogram was generated based on the risk score and clinical characteristics. Gene pathway level, microenvironment, expression of targeted therapy-associated genes, response to immunotherapy, drug sensitivity, and somatic mutation status were compared between clusters. Eighteen prognostic MRGs (DNM1L, PUSL1, CHCHD4, COX7A1, CPT1A, CYP27A1, POLDIP2, PCK2, MRPL2, PDK3, PDK4, MARC2, ACSM3, COA7, THNSL1, ATAD3B, C15orf48, TOMM70A) were identified to construct the risk model. Remarkable discrepancies were observed between groups. The high-risk group had shorter overall survival, less immune infiltration, lower CD20 and higher PD-L1 expression than the low-risk group. Distinct immune microenvironment, responses to immunotherapy and predictive drug IC50 values were found between groups. We established a novel prognostic mitochondria-related signature by machine learning algorithm, which also demonstrated outstanding predictive value in tumor microenvironment and responses to therapies.

Increased Co-Expression of PD-L1 and CTLA-4 Predicts Poor Overall Survival in Patients with Acute Myeloid Leukemia Following Allogeneic Hematopoietic Stem Cell Transplantation.

Our previous study has demonstrated that high expression of immune checkpoints (ICs) was significantly associated with adverse clinical outcomes in patients with acute myeloid leukemia (AML). This study aims to investigate the significance of the alteration of IC co-expression for evaluating the prognosis of AML patients following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Quantitative real-time PCR (qRT-PCR) data of bone marrow (BM) samples from 62 de novo AML patients, including 37 patients who received allo-HSCT and 25 patients who received chemotherapy only, were used for prognostic analysis. High expression of PD-1, PD-L1, PD-L2, CTLA-4, and LAG-3 was associated with poor overall survival (OS) in AML patients receiving allo-HSCT, while the expression levels of PD-1, PD-L2, CTLA-4, and LAG-3, other than PD-L1, were not significantly correlated with OS in AML patients receiving chemotherapy. Importantly, PD-L1/CTLA-4 was the best combination model for predicting poor OS in AML patients following allo-HSCT, especially combined with minimal residual disease (MRD). High expression of ICs in BM of AML patients following allo-HSCT was related to poor outcomes, and increasing co-expression of PD-L1 and CTLA-4 might be one of the best immune biomarkers to predict outcomes in patients with AML.

DRG2 as a Biomarker to Enhance the Predictive Efficacy of PD-L1 Immunohistochemistry Assays.

PD-L1 immunohistochemistry (IHC) assays are used as a companion diagnostic for immunotherapy with immune checkpoint inhibitors (ICIs). However, despite the association between PD-L1 expression and clinical benefit from ICIs, the PD-L1 IHC assay is not sufficiently accurate in predicting response to ICIs; some patients with high PD-L1 expression do not respond to ICIs. Recently, researchers provided insights into why some patients with high PD-L1 expression fail to respond to ICIs. They discovered that DRG2 is a critical regulator of PD-L1 endosomal trafficking in cancer cells, which is essential for the proper localization of PD-L1 on the cell surface. Although DRG2-depleted cells express high levels of PD-L1 and are PD-L1 IHC-positive, the PD-L1 sequestered in early endosomes does not respond to ICIs. Therefore, a companion diagnostic combining DRG2 expression with a PD-L1 IHC assay may improve the therapeutic response to PD-1/PD-L1 ICIs.

Macrophages promote pre-metastatic niche formation of breast cancer through aryl hydrocarbon receptor activity

Macrophages that acquire an immunosuppressive phenotype play a crucial role in establishing the pre-metastatic niche (PMN), which is essential for facilitating breast cancer metastasis to distant organs. Our study showed that increased activity of the aryl hydrocarbon receptor (AHR) in lung macrophages plays a crucial role in establishing the immunosuppressive PMN in breast cancer. Specifically, AHR activation led to high expression of PD-L1 on macrophages by directly binding to the promoter of Pdl1. This upregulation of PD-L1 promoted the differentiation of regulatory T cells (Tregs) within the PMN, further enhancing immunosuppressive conditions. Mice with Ahr conditional deletion in macrophages had reduced lung metastasis of breast cancer. The elevated AHR levels in PMN macrophages were induced by GM-CSF, which was secreted by breast cancer cells. Mechanistically, the activated STAT5 signaling pathway induced by GM-CSF prevented AHR from being ubiquitinated, thereby sustaining its activity in macrophages. In breast cancer patients, the expression of AHR and PD-L1 was correlated with increased Treg cell infiltration, and higher levels of AHR were associated with a poor prognosis. These findings reveal that the crosstalk of breast cancer cells, lung macrophages, and Treg cells via the GM-CSF-STAT5-AHR-PD-L1 cascade modulates the lung pre-metastatic niche during breast cancer progression.

Tissue Expression and Plasma Soluble PD-L1 Levels in Patients With Endometrial Cancer.

The prognostic role of tissue PD-L1 expression in endometrial cancer (EC) remains controversial. Moreover, its value in guiding anti-PD1/PD-L1 immunotherapy is questionable. The eventual role of soluble PD-L1 (sPD-L1), released by cancer tissue and circulating immune cells, is largely unexplored. In this pilot study, we investigated the expression of PD-L1 in cancer cells and tumor stroma infiltrating inflammatory cells (TIICs), in parallel with sPD-L1 levels in the plasma of 19 patients with early-stage endometrioid EC, before and after hysterectomy. Cancer cell membrane staining was noted in 5/19 (26.3%) cases (range=1-5%; median 1% of the cancer cell population). IICs showed positive reactivity in 14/19 (73.7%) cases. sPD-L1 plasma levels ranged from 53-408 pg/ml and 113-557 pg/ml, respectively, in the plasma of patients before and after hysterectomy (p=0.01). High PD-L1 expression by IIC was marginally associated with a high histology grade (p=0.08). High sPD-L1 levels before surgery were significantly associated with ICC PD-L1 expression (p=0.0007), high histology grade (p=0.04), and marginally with T2-stage (p=0.08). sPD-L1 is easily detectable in the plasma of EC patients and may be associated with aggressive clinical features and PD-L1-expressing immune cells infiltrating the tumor stroma. sPD-L1 plasma levels in EC patients undergoing immunotherapy can be further tested as a biomarker for therapeutic stratification.

Decoding the pathological and genomic profile of epithelial ovarian cancer.

Ovarian cancer (OC) is one of the most common cancers in women, with a high mortality rate. Most of published studies have been focused on Caucasian populations, with the need to explore biological features and clinical outcomes of patients from other ethnicities. We described clinical outcome (progression-free survival and overall survival) and biomarkers associated with survival in a cohort of patients with OC from Tunisia. Using immunohistochemistry, we assessed the expression of 14 proteins known to be altered in OC in a cohort of 198 patients. We explored the correlation between protein expression and copy number alteration (CNA) profiles. FIGO stage, menopausal status and mismatch repair deficiency were associated with survival. ERBB2 amplification was correlated with high ERBB2 expression (OR = 69.32, p = 4.03 E-09), and high PDL1 expression was associated to CD274 amplification (OR = 4.97, p = 5.79 E-2). We identified a correlation between survival and exposure to two CNA signatures (MAPK pathway and BRCA-related homologous recombination deficiency). Moreover, Gama-H2AX protein expression was correlated with exposure to a genomic signature associated with homologous recombination deficiency. We observed that OC clinical and pathological characteristics of these patients from Tunisia were similar to those of Caucasian patients. We identified frequent CNA in this population that need to be confirmed in other sets from Africa.

PD-L1 promotes tumor metastasis by regulating the infiltration of FGFBP2(+)Tm cells in colorectal cancer.

Tumor-infiltrating lymphocytes can influence tumorigenesis and progression. We found PD-L1 can inhibit the infiltration of memory T (Tm) cells in vivo and in vitro by reducing the secretion of CXCL9, CXCL10 in colorectal cancer. Patients with high PD-L1 expression have minimal Tm cell infiltration, accompanied with a higher incidence of tumor metastasis. Single-cell sequencing revealed that PD-L1 mainly inhibited the infiltration of a specific Tm cell subset characterized by the expression of FGFBP2 gene. To clarify the distribution of FGFBP2(+)Tm cells, peripheral blood, lymph nodes, colon polyps, primary tumor, and liver metastases samples were collected. As the tumor progressed, the infiltration of FGFBP2(+) memory T cells gradually increased and accumulated in liver metastases. By establishing a mouse metastasis model, we found in high PD-L1 expression group, the luciferin intensity of metastatic tumor was significantly higher, the number of metastatic nodules and the weight of metastases were also increased. The number of FGFBP2(+) Tm cells in peripheral blood and in liver/lung metastases were increased. Therefore, the expression of PD-L1 in primary tumor can promote the occurrence of metastases, and FGFBP2(+)Tm cells may be involved in the formation of metastases. Furthermore, the result showed that the number of FGFBP2(+) Tm cells in metastases was positively correlated with the number of vessels in liver/lung metastases. In conclusion, we confirmed that the expression of PD-L1 in primary tumor can increase the number of FGFBP2(+) Tm cells in peripheral blood and promote tumor metastasis, which is likely to be caused by the angiogenesis of FGFBP2(+) Tm cells in metastases.

Abstract C011: The impact of reproductive factors on breast tumor and normal-adjacent tissue immune profile from menarche to menopause

Abstract Background: Reproductive factors and sex hormones are tightly linked to systemic immunity. However, no studies have examined whether reproductive factors and exogenous hormone use modulate the immune microenvironment of breast tissue. Methods: We prospectively evaluated the associations of reproductive factors (age at menarche, parity, age at first birth, age at menopause, and menopausal status) and exogenous hormone use (oral contraceptives, and menopausal hormone therapy (MHT)) with breast tumor and normal-adjacent tissue immune cell markers among 935 breast cancer cases in the Nurses’ Health Studies. We deconvoluted immune cell abundance using CIBERSORTx and derived gene expression signatures of markers for immune checkpoint (PD1, PDL1, and CTLA4), co-regulatory signal and antigen presentation (MHC class I/ II and T cell receptor) and mammary cytokine signaling (IFN gamma, IL2, IL4, IL12, IL13, TGF beta). Linear regression was used with adjustment for potential confounders. Results: Majority of participants had estrogen receptor (ER)-positive breast cancer (81%) and were post-menopausal at diagnosis (72%). Compared to tumors from pre-menopausal women, tumors from post-menopausal women had higher signature scores for tumor pro-inflammatory cytokine signaling (IFN gamma, IL2, IL4, IL12, IL13, TGF beta) and antigen presentation (FDR≤0.05). Several of the inflammatory cytokine signatures showed modest inverse relations with signatures of immune checkpoint markers (ρ=-0.3 to -0.4). Women who reported current use of estrogen only MHT had higher expression of CTLA4 in ER-positive breast tumors. For normal-adjacent tissues of ER-positive tumors, parity was associated with higher CD8+ T cell abundance, higher PDL1 expression and lower cytokine signaling in normal-adjacent tissues at p≤0.05; while breastfeeding was associated with lower abundance of CD8+ T cell and higher expression of cytokine signaling in normal-adjacent tissues of ER-negative tumors (p≤0.05). None of the associations in normal-adjacent tissues met FDR significance. The associations between other reproductive factors and immune cell profiles were in general weak. Conclusions: Our study suggests pre-diagnostic reproductive factors may influence breast tumor immune profiles. Future studies are needed to validate these results. Citation Format: Cheng Peng, Yuxi Liu, Yujing Heng, Clara Bodelon, Daniel Stover, Wendy Y. Chen, Michelle D. Holmes, A. Heather Eliassen, Peter Kraft, Rulla M. Tamimi. The impact of reproductive factors on breast tumor and normal-adjacent tissue immune profile from menarche to menopause [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C011.

Long-term outcomes among patients who respond within the first year to nivolumab plus ipilimumab or nivolumab monotherapy: A pooled analysis in 935 patients

PurposeTo investigate the predictive value of RECIST response within 3, 6, or 12 months on long-term survival, and explore differences between nivolumab+ipilimumab and nivolumab monotherapy, we analyzed pooled 5-year data of 935 responder and non-responder patients at various time points after treatment initiation in CheckMate 069, 066, and 067 studies. Patients and methodsTreatment-naive advanced melanoma patients received nivolumab+ipilimumab or nivolumab monotherapy. To decrease immortal time bias, 3-, 6-, or 12-month overall survival (OS) and progression-free survival (PFS) landmark analyses were performed. Association between characteristics and response was evaluated by univariate and multivariate analyses. ResultsResponse rates at any time were 58 % (239/409) for nivolumab+ipilimumab and 44 % (230/526) for nivolumab monotherapy. In 12-month landmark analyses, 5-year OS rates for responders versus non-responders were 82 % versus 40 % with nivolumab+ipilimumab (HR=0.23 [95 % CI, 0.15–0.35]) and 76 % versus 32 % with nivolumab monotherapy (HR=0.22 [95 % CI, 0.16–0.31]). PFS rates were 83 % versus 32 % and 69 % versus 46 %, respectively. Similar strong associations between response at 3 and 6 months and 5-year OS and PFS were also observed with more than 70 % of the responses observed in the first 3 months. Response rates correlated with baseline LDH and PD-L1 status by multivariate analysis but the association between response and long-term survival was maintained in landmark analyses even among patients with high LDH and low PD-L1 expression. ConclusionClinical response evaluated in the first months of therapy is a strong predictor of long-term survival, even in patients with poor prognostic biomarkers.

Recurrence-free patient who underwent surgery after pembrolizumab combination chemotherapy for locally advanced pulmonary pleomorphic carcinoma with high PD-L1 expression

Recurrence-free patient who underwent surgery after pembrolizumab combination chemotherapy for locally advanced pulmonary pleomorphic carcinoma with high PD-L1 expression

Real-World Study on Implementation of Genomic Tests for Advanced Lung Adenocarcinoma in Brazil.

Tissue inadequacy and operational challenges may limit lung cancer comprehensive biomarker testing. Here, we describe the initial implementation of a tailored tissue molecular journey at Oncoclínicas Precision Medicine Laboratory in Brazil, which includes fast-track (FT) non-next-generation sequencing (NGS) assays combined with a broad NGS panel. From 2021 to 2023, all nonsquamous lung cancer samples eligible for the patient support program "Lung Mapping Consortium" at Oncoclínicas & Co were evaluated using the FT panel (immunohistochemistry for PD-L1 and anaplastic lymphoma kinase [ALK], polymerase chain reaction for EGFR and BRAF, and fluorescence in situ hybridization for ROS1) plus a broad DNA and RNA sequencing panel of 180 genes (custom ARCHER panel). From 1,272 samples received by the laboratory, 3% had no tissue for any molecular testing, 20% was not eligible for broad NGS panel as per pathologist assessment (tumor purity and quantity), additional 12% did not reach presequencing analytical thresholds (nucleic acid quantity and/or quality), and 3% had postsequencing failure. Most frequent alterations were KRAS mutations (28.4%, KRASG12C 9.7%), EGFR mutations (23.6%, exon20 insertions 2.9%), ALK fusions (6.4%), MET exon 14 skipping (4.4%), ERBB2 mutations (3.4%), ROS1 fusions (3.1%), and BRAFV600E (1.9%). In 35% of the samples, FT non-NGS tests were the only molecular diagnostics: EGFR mutations (14%), ALK fusions (4.4%), ROS1 fusions (1.8%), and BRAFV600E (0.7%). Overall, high PD-L1 expression (≥50%) was found in 12.3%. This study provides data on the molecular epidemiology of lung adenocarcinoma in Brazil, confirming high prevalence of EGFR mutations, ALK fusions, and MET exon 14 skipping alteration. Biomarker detection is largely affected by biospecimen collection and processing, with one third of the patients eligible for non-NGS testing only, which presents reduced coverage and sensitivity for actionable drivers.

Spatially Resolved Whole-Transcriptomic and Proteomic Profiling of Lung Cancer and Its Immune Microenvironment According to PD-L1 Expression.

The expression of PD-L1 on tumor cells (TC) is used as an immunotherapy biomarker in lung cancer, but heterogeneous intratumoral expression is often observed. To better understand heterogeneity in the lung cancer tumor microenvironment, we performed proteomic and whole-transcriptomic digital spatial profiling analyses of TCs and immune cells (IC) in spatially matched areas based on tumor PD-L1 expression and the status of the immune microenvironment. We validated our findings using IHC, data from The Cancer Genome Atlas, and immunotherapy cohorts. ICs in areas with high PD-L1 expression on TCs showed more features, indicative of immunosuppression and exhaustion, than ICs in areas with low PD-L1 expression on TCs. TCs highly expressing PD-L1 within immune-inflamed areas showed upregulation of proinflammatory processes, whereas TCs highly expressing PD-L1 within immune-deficient areas showed upregulation of various metabolic processes. Using differentially expressed genes of TCs between the immune-inflamed and immune-deficient areas, we identified a prognostic gene signature for lung cancer. In addition, we found that a high ratio of CD8+ cells to M2 macrophages predicted favorable outcomes in patients with PD-L1-expressing lung cancer after immune checkpoint inhibitor therapy. Overall, this study demonstrates that TCs and ICs have distinct spatial features within the lung tumor microenvironment that are related to tumor PD-L1 expression and IC infiltration.

TROPION-Lung07: Phase III study of Dato-DXd+pembrolizumab±platinum-based chemotherapy as 1L therapy for advanced non-small-cell lung cancer.

For patients with advanced/metastatic non-small-cell lung cancer (NSCLC) without actionable genomic alterations and low (<50%) PD-L1 expression, pembrolizumab plus pemetrexed and platinum chemotherapy is a preferred first-line treatment. These patients have comparatively worse outcomes than those with higher PD-L1 expression, underscoring the need for new combination strategies. Datopotamab deruxtecan (Dato-DXd), a TROP2-directed antibody-drug conjugate, has demonstrated encouraging antitumor activity and safety in this patient population. We describe the rationale and design of TROPION-Lung07, a randomized, open-label Phase III study assessing Dato-DXd in combination with pembrolizumab with/without platinum-based chemotherapy versus pembrolizumab plus pemetrexed and platinum-based chemotherapy in patients with advanced/metastatic non-squamous NSCLC without actionable genomic alterations and <50% PD-L1 expression. Primary study objectives are progression-free survival and overall survival.Clinical Trial Registration: NCT05555732 (ClinicalTrials.gov).

Dysgerminomas: germ cell tumors exhibit high expression of PD-L1 and associated with high TILs and good prognosis

Ovarian germ cell tumors (OVGCTs) account for 28% of all diagnosed ovarian cancers, and malignant germ cell tumors specifically account for approximately 13% of diagnosed ovarian cancers in Saudi Arabia. Although most germ cell tumor patients have a high survival rate, patients who experience tumor recurrence have a poor prognosis and present with more aggressive and chemoresistant tumors. The use of immunotherapeutic agents such as PD-L1/PD-1 inhibitors for OVGCTs remains very limited because few studies have described the immunological characteristics of these tumors. This study is the first to investigate PD-L1 expression in ovarian germ cell tumors and explore the role of PD-L1 expression in tumor microenvironment cells and genetic alterations. A total of 34 ovarian germ cell tumors were collected from pathology archives. The collected tumor tissues included ten dysgerminomas, five yolk sac tumors, five immature teratomas, and one mature teratoma, and the remaining samples were mixed germ cell tumors. The tumors were analyzed using immunohistochemical analysis to determine PD-L1 expression, immune cell infiltration and cancer stem cell populations and their correlation with clinical outcome. Furthermore, the genetic alterations in different subtypes of germ cell tumors were correlated with PD-L1 expression and clinical outcome. Datasets for testicular germ cells (TGCTs) were retrieved from The Cancer Genome Atlas (TCGA) and analyzed using cBioPortal (cbioportal.org) and Gene Expression Profiling Interactive Analysis (GEPIA). Compared with yolk sac tumors, dysgerminomas highly express PD-L1 and are associated with high levels of tumor infiltrating lymphocytes (TILs) and stem cell markers. In addition, compared with PD-L1-negative yolk sac tissue, dysgerminomas/seminomas with high PD-L1 expression are associated with more genetic alterations and a better prognosis. Our findings will contribute to the knowledge about the potential benefits of ovarian cancer immunotherapy in specific subsets of germ cell tumor patients and the risk factors for resistance mediated by tumor microenvironment cells.

Can multiplexing Immunohistochemistry for PD-L1, CD68, and CD3 improve scoring for “Keytruda®” Indication?

Abstract Introduction/Objective FDA-approved companion diagnostics immunohistochemistry scoring for PD-L1 is essential for Keytruda ® treatment in patients with NSCLC. The challenge with PD-L1 testing alone is false positive PD-L1 expression score due to alveolar macrophage infiltration. Multiplexing with PD-L1, CD68, and CD3 could help alleviate this issue. By viewing PD-L1 expression on tumor cells, CD68 expression on macrophages, and the presence of CD3+ T cells on a single slide, pathologists will be able to see the presence of an immune microenvironment (high PD-L1 expression with abundant macrophages) and the potential for response to other types of Immunotherapies (presence of T cells). Methods/Case Report Positive NSCLC FFPE blocks were sectioned and stained using Agilent Dako Omnis. Two combinations of multiplex staining were prepared for each block by staining PD-L1 (brown) alone first followed by CD3 and CD68. First slide: CD3(Vina Green), CD68(Magenta); Second slide: CD3(Magenta), CD68(Vina Green). To prevent wash out, dehydration and clearing occurred with two changes of 100% alcohol and three changes of xylene for manual cover slipping. Results (if a Case Study enter NA) Manual scoring of PD-L1 alone vs two different multiplex combinations was compared to Agilent Proscia digital AI scoring using a preliminary study set (9 positives, 2 negatives). CD68-green and CD3-magenta showed better discrimination than CD68-magenta and CD3-green at a glance. This could be due to the staining intensity and nonspecific background staining of CD68-magenta. Manual scoring was higher compared to digital scoring, which could be due to the human error of positive bias. Digital scoring was significantly lower for PD-L1 alone vs both multiplex stains. The digital scoring for the multiplex stains showed a higher scoring percentage by removing false positive macrophages. Conclusion Reflex scoring workflow is being developed to focus on difficult cases using the multiplex triple stain, i.e. clear negative and clear &amp;gt;50% with 3+ intensity. More cases will be collected and studied to further investigate the improved PD-L1 scoring with digital imaging assisted by artificial intelligence and to compare the multiplex color combinations.

The tumor immune microenvironment of SCLC is not associated with its molecular subtypes

IntroductionSmall-cell lung carcinoma (SCLC) is a high-grade neuroendocrine carcinoma of poor prognosis. Although immune checkpoint blockers have shown promising results in advanced SCLC, the tumor immune microenvironment (TME) remains poorly understood, with no validated prognostic or predictive biomarkers of efficacy. MethodsThis retrospective study included surgically samples from 48 SCLC patients between 2009 and 2018. We assessed the TME using two quantitative 7-plex immunofluorescence panels focusing on T and B cells, and compared it to NSCLC (N = 10). Molecular subtypes were determined by assessing the expression of ASCL1, NEUROD1 and YAP1 using immunohistochemistry. ResultsImmune-hot SCLC were defined as those exhibiting the highest immune cell and immune-related marker densities. They were associated with longer overall survival, significantly more frequently detected at early stages, and exhibited high PD-L1 expression in immune cells, but were not associated with molecular subtypes. Compared to NSCLC, SCLC had significantly lower densities of CD20 + cells and higher density of PD1 + cells, with no significant differences in CD4 + , CD8 + and plasma cell densities. In univariate analysis, the highest OS was significantly associated with early stage (p < 0.001), low expression of NEUROD1 (p = 0.047), high PD1 + cell density (p < 0.001) and high PD-L1 immune cell expression (p = 0.04). Only stage and PD1 + cell density emerged as independent prognostic markers. ConclusionSCLC TME is highly heterogeneous. Immune-hot tumors were associated with OS but not with molecular classification. PD1 expression and PD-L1 expression by immune cells may thus serve as a prognostic marker.

Role of Immunotherapy in Non-Small Cell Lung Cancer (NSCLC)

Background: Non-small cell lung cancer accounts for approximately 85% of all lung cancers and presents a serious public health challenge due to an increasing incidence and poor prognosis, with only a 5-year survival rate of 5-10% in advanced disease stages. Objective: The aim of this work is an overview of the clinical efficacy and safety profile of ICIs in NSCLC patients, mainly focusing on the predictive role played by PD-L1 expression and tumor mutational burden as predictive biomarkers of treatment response. Methods: A total of 63 NSCLC patients treated with ICIs at a Department of Respiratory Medicine, Dhaka National Medical Institute Hospital, Dhaka, Bangladesh and National Institute of Diseases of the Chest and Hospital (NIDCH), and National Institute of Cancer Research &amp; Hospital (NICRH), Mohakhali, Dhaka, Bangladesh from July 2023 to December 2023, were retrospectively analyzed. Demographical information, treatment regimens, and clinical outcomes were collected and analyzed. Treatment responses were evaluated based on Response Evaluation Criteria in Solid Tumors, and safety was assessed through monitoring adverse events. Results: The median age of the cohort was 62 years, with presentation in advanced stages, III and IV in 70%. An objective response rate of 42% was observed; median PFS was 8.5 months. Of note, patients with high PD-L1 expression of ≥ 50% had a response rate of 60%, whereas those with lower expression had a rate of 30%. It was observed in TMB analysis that high mutational burden is associated with a median PFS of 10 months versus 5 months in the case of low TMB. About 15% of patients developed adverse events, mostly immune-mediated. Conclusion: This study has exemplified the promising efficacy of ICIs in the improvement of treatment outcomes for patients with NSCLC and underlined critical roles that PD-L1 expression and TMB have played in guiding personalized treatment strategies. Although encouraging, these findings are retrospective and ..

6850 A Case of Anaplastic Thyroid Carcinoma With a Complete Metabolic Response to Pembrolizumab

Abstract Disclosure: E. Tirthani: None. J.T. Kung: None. Background: Anaplastic thyroid carcinoma (ATC) is an aggressive disease with limited therapeutic options and generally poor prognosis. Post-surgery, most patients are treated with a combination of chemotherapy, radiation, and tyrosine kinase inhibitors +/- immune checkpoint inhibitors. We describe a unique case of ATC with a complete metabolic response to pembrolizumab, a selective PD-1 inhibitor, as evidenced by imaging. Clinical Case: A 69-year-old female presented to the clinic for evaluation of a rapidly enlarging neck mass. The initial ultrasound showed a large mixed cystic-solid right thyroid nodule with irregular margins with micro- and macrocalcifications, which was biopsied. Cytology showed discohesive high-grade malignant tumor cells with enlarged nuclei, nuclear hyperchromasia in the background of necrosis, and dense neutrophilic infiltration concerning for ATC. A CT scan of the neck and chest showed a complex cystic thyroid mass with central necrosis and calcification with paratracheal, supraclavicular, and mediastinal lymphadenopathy. MRI of the brain was negative for metastatic disease. The patient underwent a total thyroidectomy with right and left level 6 and 7 neck dissection. Intra-operatively, gross extrathyroidal extension of the tumor was noted to the right carotid, larynx, right recurrent laryngeal nerve, and esophagus, with residual tumor left behind near the larynx. Pathology confirmed stage IVC ATC, positive for PIK3CA, NF1, p53 mutations, and BRAF negative. 90% of tumor cells showed PD-L1 expression on immunohistochemical staining. The post-surgical PET scan showed two discrete, well-defined foci of very intense FDG uptake, corresponding to the right lower cervical and para-esophageal lymph nodes with no evidence of distant metastasis. Systemic chemotherapy with carboplatin and paclitaxel (5 cycles) was initiated with concurrent intensity modulated radiation therapy (total 60 Gy/40 fractions to thyroid bed and bilateral neck). Repeat imaging showed minimal change in the size of the PET-positive lymph nodes. Immunotherapy was initiated and with just 2 cycles of 400 mg IV pembrolizumab, a repeat PET scan was obtained, which showed a complete metabolic response to therapy. Minimal residual FDG activity in the right supraclavicular region was thought to be secondary to posttreatment changes. The patient was able to resume her activities of daily living and had an improvement in appetite. The plan is to continue 400 mg IV pembrolizumab every 6 weeks while cautiously assessing for adverse effects from immunotherapy. Conclusion: It is rare to see a complete metabolic response to therapy with pembrolizumab without concurrent use of tyrosine kinase inhibitors in patients with ATC. A high tumoral PD-L1 expression may be the key to having this kind of dramatic response. Presentation: 6/3/2024

Algorithme thérapeutique des CBNPC sans mutation addictive

The development of immunotherapy in first-line therapy with anti-PD-1 and anti-PD-L1 has changed the first line treatment algorithm of advanced NSCLC. The anti-PD-(L)1 pembrolizumab, atezolizumab and cemiplimab clearly improve the overall survival in NSCLC with high PD-L1 expression (≥ 50 % of tumour cells), comparatively to cytotoxic chemotherapy. Combinations of anti-PD(L)-1 to platinum-based chemotherapy are superior to chemotherapy alone, regardless of PD-L1 level of expression. They represent the 1st line gold-standard when PD-L1 is expressed in less than 50 % of tumour cells and might reduce the risk of early disease progression in comparison with pembrolizumab when PD-L1 ≥ 50 %. The room for anti-CTLA-4 + anti-PD(L)-1 combinations which are not available in France remains to be established. Second-line treatment is currently based on chemotherapy, with a platinum-based doublet for patients treated in first line by pembrolizumab alone, and standard second-line chemotherapy options for patients treated by chemotherapy-immunotherapy combinations, i.e. docetaxel regardless of histology or pemetrexed for non-squamous cell carcinoma when not used in first line. Addition of an antiangiogenic agent to docetaxel only achieved a modest improvement of overall survival but neither nintedanib, nor docetaxel is available in France. Combination of paclitaxel and bevacizumab is also an option. Immunotherapy still benefits only a minority of patients whose identification is imperfect, underscoring the need for new strategies based on ne< combination amplifying the anti-tumour immune response as well as understanding the mechanisms of resistance to treatment in order to improve these results.1877-1203/© 2024 SPLF. Published by Elsevier Masson SAS. All rights reserved.