Programmed Death-ligand 1 Combined Positive Score Research Articles

Concordance of PD-L1 Expression in Metastatic Triple-negative Breast Cancer Between the 22C3 and E1L3N Antibodies Using Combined Positive Scoring.

For patients with metastatic triple-negative breast cancer (TNBC), treatment with pembrolizumab is dependent on the accurate determination of programmed death ligand 1 (PD-L1) expression using immunohistochemistry (IHC). This study evaluated the interobserver concordance in assessing PD-L1 expression on TNBC samples using the commercial 22C3 IHC assay and an in-house assay based on the E1L3N antibody. Concordance between the 22C3 and the E1L3N IHC assays was evaluated on TNBC samples read by a commercial laboratory and a Brigham and Women's Hospital breast pathologist (BWH reader). Each slide was given a PD-L1 combined positive score (CPS) and was considered PD-L1 positive or negative based on the CPS cutoff of 10. Interobserver concordance for the assays was also evaluated on a subset of samples between 2 and 3 independent readers. On 71 samples, 2 independent readers (1 BWH reader and commercial laboratory) using E1L3N and 22C3, respectively, reached agreement on PD-L1 status (positive/negative) on 64 samples (90.1%). Using 22C3, 2 independent readers reached agreement on PD-L1 status on 30 of 36 samples (83.3%), and 3 independent readers reached agreement on 16 of 27 samples (59.3%). Using E1L3N, 2 BWH readers reached agreement on PD-L1 status on 18 of 27 samples (66.7%). Three BWH readers reached an agreement on 2 of 12 of the most challenging samples (16.7%). In conclusion, concordance between E1L3N and 22C3 testing using CPS for PD-L1 in metastatic TNBC was >90%. However, certain cases were challenging to agree upon using current threshold criteria, highlighting the need for more standardized evidence-based methods to assess PD-L1 expression.

Immune microenvironmental heterogeneity according to tumor DNA methylation phenotypes in microsatellite instability-high colorectal cancers

The detailed association between tumor DNA methylation, including CpG island methylation, and tumor immunity is poorly understood. CpG island methylator phenotype (CIMP) is observed typically in sporadic colorectal cancers (CRCs) with microsatellite instability-high (MSI-H). Here, we investigated the differential features of the tumor immune microenvironment according to CIMP status in MSI-H CRCs. CIMP-high (CIMP-H) or CIMP-low/negative (CIMP-L/0) status was determined using MethyLight assay in 133 MSI-H CRCs. All MSI-H CRCs were subjected to digital pathology-based quantification of CD3 + /CD8 + /CD4 + /FoxP3 + /CD68 + /CD204 + /CD177 + tumor-infiltrating immune cells using whole-slide immunohistochemistry. Programmed death-ligand 1 (PD-L1) immunohistochemistry was evaluated using the tumor proportion score (TPS) and combined positive score (CPS). Representative cases were analyzed using whole-exome and RNA-sequencing. In 133 MSI-H CRCs, significantly higher densities of CD8 + tumor-infiltrating lymphocytes (TILs) were observed in CIMP-H tumors compared with CIMP-L/0 tumors. PD-L1 TPS and CPS in CIMP-H tumors were higher than in CIMP-L/0 tumors. Next-generation sequencing revealed that, compared with CIMP-L/0 tumors, CIMP-H tumors had higher fractions of CD8 + T cells/cytotoxic lymphocytes, higher cytolytic activity scores, and activated immune-mediated cell killing pathways. In contrast to CIMP-L/0 tumors, most CIMP-H tumors were identified as consensus molecular subtype 1, an immunogenic transcriptomic subtype of CRC. However, there were no differences in tumor mutational burden (TMB) between CIMP-H and CIMP-L/0 tumors in MSI-H CRCs. In conclusion, CIMP-H is associated with abundant cytotoxic CD8 + TILs and PD-L1 overexpression independent of TMB in MSI-H CRCs, suggesting that CIMP-H tumors represent a typical immune-hot subtype and are optimal candidates for immunotherapy in MSI-H tumors.

Evaluation of pembrolizumab plus cisplatin and fluorouracil in radical treatment for patients with T4b esophageal squamous cell carcinoma

BackgroundPembrolizumab plus cisplatin and 5-fluorouracil administered as first-line therapy for advanced esophageal cancer patients has shown a better objective response and survival than conventional chemotherapy with less severe hematological adverse events. The safety and efficacy of this regimen were evaluated in patients with T4b esophageal squamous cell carcinoma (ESCC).MethodsEight consecutive patients with T4b ESCC received this regimen according to KEYNOTE-590 as induction, and they were evaluated after 1–3 courses. The programmed death-ligand 1 (PD-L1) combined positive score (CPS) was also evaluated before chemotherapy. Efficacy for the primary lesion was evaluated by our original formula for the tumor reduction rate.ResultsThe numbers of patients with partial response (PR), stable disease, and progressive disease (PD) were 5, 1, and 2, respectively. The tumor reduction rate ranged from 69 to 87% in PR patients, and all PR patients had relief from T4b. Two patients underwent conversion surgery with R0 resection. PD-L1 CPS was over 90 in 2 PR patients, but under 10 in 2 other PR patients. PD-L1 CPS was under 10 in PD patients. One patient had hyperprogression, resulting in an esophago-pulmonary fistula. Greater than grade 3 adverse events were bleeding gastric ulcer in one patient (12.5%), neutropenia without G-CSF in 3 patients (37.5%), and hypopotassemia in 1 patient (12.5%). No patient had febrile neutropenia.ConclusionsMarked tumor reduction was confirmed in 62.5% of patients with pembrolizumab plus cisplatin and 5-fluorouracil with less adverse events. This regimen could be administered as induction chemotherapy for patients with T4b ESCC.

Efficacy and safety of surufatinib plus toripalimab in previously treated advanced tumors progressing after immunotherapy.

36 Background: Immunotherapy has resulted in significant and lasting clinical responses in non-small lung cancer (NSCLC), esophagus cancer, gastric cancer, colorectal cancer etc. However, most patients (pts) inevitably lose efficacy due to acquired resistance. This study (NCT04169672) aimed to investigate the efficacy and safety of surufatinib (a multi-kinase inhibitor of VEGFR1-3, FGFR1 and CSF1R) plus toripalimab (monoclonal humanized IgG4 programmed death 1 [PD-1] antibody) in pts with advanced solid tumors. Here, we reported the results from pts who bore different tumors and failed in previous treatments containing the checkpoint inhibitors. Methods: Eligible pts were 18~75 years old who had advanced solid tumors and received prior PD-1/programmed death-ligand 1 (PD-L1) antibody therapy for at least 3 months (m) before disease progression. Enrolled pts received surufatinib 250 mg orally once daily and toripalimab 240 mg intravenously every three weeks in a 21-day cycle. The primary endpoint was the objective response rate (ORR) per RECIST v1.1. Secondary endpoints include disease control rate (DCR), progression free survival (PFS), overall survival (OS) and safety. Results: As of data cutoff (Feb 28, 2023), a total of 28 pts were enrolled and received at least one dose of study treatment. Pts with PD-L1 combined positive score (CPS) ≥1 accounted for 67.9%. 9 pts were diagnosed with gastric cancer /gastroesophageal junction adenocarcinoma (GC/GEJ), 4 pts each with esophageal cancer, NSCLC or intestinal cancer, 2 pts with biliary tract cancer, 1 pt each with other 5 tumors. 39.3% of pts received ≥2 previous anti-tumor therapies. A variety of PD-1 antibodies were used before enrollment, which included tislelizumab (25.0%), sintilimab (17.9%), camrelizumab (14.3%), toripalimab (14.3%), pembrolizumab (7.1%), nivolumab (3.6%), etc. The median exposure duration was 4.1m for study treatment. In 27 tumor evaluable pts, the confirmed ORR and DCR were 7.4 % and 66.7%, respectively. In 28 intent-to-treat pts, the median PFS and OS were 3.94m (95% CI 1.38, 4.21) and 13.04m (95% CI 8.64, 21.59), respectively. The median survival follow-up duration was 20.90m (95% CI 16.10, 25.03). In 9 pts with GC/GEJ, the median PFS and median OS were 2.72m and 13.69m, respectively. Treatment related adverse events (TRAE) occurred in 89.3% of pts. Grade≥3 TRAEs occurred in 39.3% of pts with blood pressure increased (10.7%) and liver injury (7.1%) reported most commonly. 28.6% of pts had immune-related adverse events, among which immune-related pneumonitis (7.1%) and immune-related diabetes (7.1%) reached G3. Two TRAEs led to surufatinib discontinuation. No deaths related to either surufatinib or toripalimab. Conclusions: Surufatinib plus toripalimab showed antitumor activity and a manageable safety profile in pts with advanced solid tumors progressing after immunotherapy, especially in GC/GEJ.

Correlation of PD-L1 expression with CD8+ T cells and oxidative stress-related molecules NRF2 and NQO1 in esophageal squamous cell carcinoma.

Oxidative stress and the immune microenvironment both contribute to the pathogenesis of esophageal squamous cell carcinoma (ESCC). However, their interrelationships remain poorly understood. We aimed to examine the status of key molecules involved in oxidative stress and the immune microenvironment, as well as their relationships with each other and with clinicopathological features and prognosis in ESCC. The expression of programmed death-ligand 1 (PD-L1), CD8, nuclear factor erythroid-2 related factor-2 (NRF2), and NAD(P)H quinone oxidoreductase 1 (NQO1) was detected using immunohistochemistry in tissue samples from 176 patients with ESCC. We employed both combined positive score (CPS) and tumor proportion score (TPS) to evaluate PD-L1 expression and found a positive correlation between CPS and TPS. Notably, PD-L1 expression, as assessed by either CPS or TPS, was positively correlated with both NRF2 nuclear score and NQO1 score in stage II-IV ESCC. We also observed a positive correlation between the density of CD8+ T cells and PD-L1 expression. Furthermore, high levels of PD-L1 CPS, but not TPS, were associated with advanced TNM stage and lymph node metastases. Moreover, both PD-L1 CPS and the nuclear expression of NRF2 were found to be predictive of shorter overall survival in stage II-IV ESCC. By using the Mandard-tumor regression grading (TRG) system to evaluate the pathological response of tumors to neoadjuvant chemotherapy (NACT), we found that the TRG-5 group had higher NRF2 nuclear score, PD-L1 CPS, and TPS in pre-NACT biopsy samples compared with the TRG-3 + 4 group. The NQO1 scores of post-NACT surgical specimens were significantly higher in the TRG-5 group than in the TRG 3 + 4 group. In conclusion, the expression of PD-L1 is associated with aberrant NRF2 signaling pathway, advanced TNM stage, lymph node metastases, and unfavorable prognosis. The dysregulation of PD-L1 and aberrant activation of the NRF2 signaling pathway are implicated in resistance to NACT. Our findings shed light on the complex interrelationships between oxidative stress and the immune microenvironment in ESCC, which may have implications for personalized therapies and improved patient outcomes.

An artificial intelligence-powered PD-L1 combined positive score (CPS) analyser in urothelial carcinoma alleviating interobserver and intersite variability.

Immune checkpoint inhibitors targeting programmed death-ligand 1 (PD-L1) have shown promising clinical outcomes in urothelial carcinoma (UC). The combined positive score (CPS) quantifies PD-L1 22C3 expression in UC, but it can vary between pathologists due to the consideration of both immune and tumour cell positivity. An artificial intelligence (AI)-powered PD-L1 CPS analyser was developed using 1,275,907 cells and 6175.42 mm2 of tissue annotated by pathologists, extracted from 400 PD-L1 22C3-stained whole slide images of UC. We validated the AI model on 543 UC PD-L1 22C3 cases collected from three institutions. There were 446 cases (82.1%) where the CPS results (CPS ≥10 or <10) were in complete agreement between three pathologists, and 486 cases (89.5%) where the AI-powered CPS results matched the consensus of two or more pathologists. In the pathologist's assessment of the CPS, statistically significant differences were noted depending on the source hospital (P = 0.003). Three pathologists reevaluated discrepancy cases with AI-powered CPS results. After using the AI as a guide and revising, the complete agreement increased to 93.9%. The AI model contributed to improving the concordance between pathologists across various factors including hospital, specimen type, pathologic T stage, histologic subtypes, and dominant PD-L1-positive cell type. In the revised results, the evaluation discordance among slides from different hospitals was mitigated. This study suggests that AI models can help pathologists to reduce discrepancies between pathologists in quantifying immunohistochemistry including PD-L1 22C3 CPS, especially when evaluating data from different institutions, such as in a telepathology setting.

Folate Receptor Alpha Expression and the Tumor Immune Microenvironment in Patients with Cervical Cancer.

Folate receptor α (FRα) is a cell-surface protein and an attractive target for cancer treatment. We investigated the association between FRα expression and the tumor immune microenvironment in patients with cervical cancer. We examined whole tumor sections of 123 patients with cervical cancer: 67 and 56 sections of squamous cell carcinoma (SCC) and non-SCC, respectively. FRα expression was assessed using immunohistochemical staining with the anti-FRα monoclonal antibody clone 26B3. Programmed death-ligand 1 (PD-L1) expression was assessed using a combined positive score (CPS). The intratumoral CD3 and CD8 cell densities were calculated as the average number of positive cells in five independent areas. FRα-positivity was identified in 72.4% of the patients, and it differed by histology (SCC vs. non-SCC; 55.2% vs. 92.9%, P<0.001). PD-L1 status was positive (CPS ≥1) in 75.6% and was more commonly expressed in patients with SCC (SCC vs. non-SCC; 83.5% vs. 66.1%, P=0.02). FRα expression had a weak correlation with PD-L1 expression (r=-0.22, P<0.001) and CD8-positive cells (r=-0.19, P=0.03). FRα-positivity was more frequently observed in the PD-L1 CPS <10 group than in the PD-L1 CPS ≥10 group (81% vs. 64%, P=0.03). FRα-high was significantly associated with poor prognosis, especially in the PD-L1 CPS ≥10 groups (hazard ratio: 4.10, 95% confidence interval: 1.39-12.06, P=0.01). In conclusion, FRα expression was higher in patients with cervical cancer and PD-L1 CPS <10 than in those with CPS ≥10. Targeting FRα expression may be a potential therapeutic strategy for cervical cancer patients with low or negative PD-L1 expression.

Clinical outcomes and biomarker exploration of first-line PD-1 inhibitors plus chemotherapy in patients with low PD-L1-expressing of gastric or gastroesophageal junction adenocarcinoma

BackgroundThe beneficial effects of first-line programmed death-1 (PD-1) inhibitors plus chemotherapy in patients with low programmed death-ligand 1 (PD-L1)-expressing advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma are controversial.MethodsWe conducted a retrospective analysis of patients with G/GEJ adenocarcinoma who had undergone first-line treatment with PD-1 inhibitors plus chemotherapy between October 2017 and May 2022. The primary outcomes were objective response rate (ORR) and progression-free survival (PFS). SPSS software V27.0 was used for data analysis.ResultsOf 345 enrolled patients, 290 had measurable lesions. The overall ORR was 59.3%. PD-L1 status was available in 171 patients, and 67.8% of them were considered as low PD-L1 expression level (combined positive score (CPS) < 5). Patients with PD-L1 CPS < 5 showed a lower response rate (51.1% vs 70.8%, P = 0.024) and a worse PFS (P = 0.009) compared to those with PD-L1 CPS ≥ 5. In the PD-L1 low-expression cohort, patients with non-diffuse type, GEJ cancer, synchronous metastasis, distant lymph node metastasis, liver metastasis, non-peritoneal metastasis, and HER2 positive were significantly associated with higher response rates to PD-1 inhibitors plus chemotherapy (P < 0.05). The presence of peritoneal metastasis (P = 0.028) and diffuse type (P = 0.046) were identified as independent predictors of poor PFS in multivariate analysis of the PD-L1 CPS < 5 subgroup. When evaluated for correlation with overall survival (OS) in the PD-L1 low-expression subgroup, peritoneal metastasis was found to be the only independent prognostic factor of an increased risk of death (hazard ratio: 2.31, 95% CI 1.09–4.90; P = 0.029).ConclusionsPD-L1 CPS ≥ 5 is significantly associated with improved response and extended PFS in G/GEJ cancer patients treated with a combination of PD-1 inhibitors and chemotherapy. Specific subgroups within the low PD-L1-expressing population, such as those with non-diffuse-type tumors and without peritoneal metastases, may also benefit from immunotherapy combined with chemotherapy.

Concordance of PD-L1 combined positive score (CPS) analysis between primary gastric cancer and matched peritoneal metastasis.

e16068 Background: Peritoneum represents one of the most common metastatic sites of gastroesophageal adenocarcinoma (GEA) and is associated with poor prognosis. Programmed death-ligand 1 (PD-L1) expression is a recognized predictive biomarker of response to immune checkpoint inhibitors (ICIs) in the first-line setting. However, data from pivotal trials showed poorer clinical efficacy of ICIs in the sub-set of patients with peritoneal involvement, regardless of PD-L1 score magnitude. Here, we investigated the temporal and spatial heterogeneity of PD-L1 expression between primary tumor and matched peritoneal metastasis. Methods: PD-L1 expression according to CPS was determined by immunohistochemistry using VENTANA PD-L1 (SP263) assays on formalin-fixed paraffin-embedded (FFPE) tumor tissues derived from 22 patients treated at our institution for advanced GEA from September 2015 to August 2023. Concordance rate of PD-L1 expression between primary tumor and matched peritoneal metastasis using PD-L1 CPS cut-off of 1 and 5 was reported (spatial heterogeneity); additionally, concordance between PD-L1 value before and after the administration of systemic treatments was analyzed (temporal heterogeneity). Results: 12(54.5%)/5(22.7%) primary tumor samples and 12(54.5%)/1(4.5%) peritoneal metastases showed PD-L1 CPS ≥ 1/ ≥ 5, respectively. Concordance of PD-L1 CPS between primary and peritoneal specimens was 54.5% and 72.7% according to CPS cuts-off of 1 and 5, respectively, highlighting marked spatial heterogeneity. High concordance rate (94%) was reported between negative PD-L1 CPS primary tumor samples and matched peritoneal metastases, against the cut-off of CPS ≥ 5; in contrast, none of the positive primary tumor samples retained PD-L1 expression in the peritoneum. Evident temporal heterogeneity of PD-L1 expression was also observed, with 56% concordance against CPS ≥ 5 in the pre- versus post-treatment comparison. Conclusions: PD-L1 expression in GEA is characterized by spatial and temporal heterogeneity which is more prominent for lower CPS cut-offs values. This evidence could hamper its role as predictive biomarker for ICIs. The high intra-patient discordance rate of PD-L1 CPS expression between positive primary tumor samples and matched peritoneal metastases suggests that peritoneal specimens should not be recommended as the preferred source for PD-L1 assessment.

HB-200 arenavirus-based immunotherapy plus pembrolizumab as first-line treatment of patients with recurrent/metastatic HPV16-positive head and neck cancer: Updated results.

6005 Background: Treatment options are limited for patients with recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) with no approved treatment specifically targeting human papillomavirus (HPV) 16-positive tumors. In the first-line (1L) R/M setting, only a minority of patients (~20%) respond to pembrolizumab monotherapy, including those with high programmed death ligand 1 (PD-L1) expression in the tumor. HB-200 comprises an alternating sequence of two replicating attenuated arenavirus vectors derived from LCMV (HB-201) and Pichinde virus (HB-202), respectively. HB-200 vectors express a non-oncogenic HPV16 E7E6 fusion protein and induce E6 and E7-specific CD8 T-cell responses. Previously, we reported promising preliminary clinical activity of HB-200 in combination with pembrolizumab as 1L treatment for patients with HPV16+ PD-L1+ R/M HNSCC. Here, we report updated results with a focus on PD-L1 status. Methods: In this non-randomized Phase 2 part of the study, participants with HPV16+ PD-L1 combined positive score (CPS) ≥1 R/M HNSCC were treated with HB-200 intravenously (every 3 weeks [Q3W] then Q6W) in combination with pembrolizumab (200 mg Q3W or 400 mg Q6W). Safety, T cell response, and preliminary antitumor activity were assessed. Results: As of 12 January 2024, 42 patients with HPV16+ PD-L1+ R/M HNSCC (41 of oropharynx as primary cancer site) were treated with HB-200 plus pembrolizumab in the 1L setting. Median follow-up time was 5.6 months. Characteristics of this cohort included: median age 66 years (range 50-77), 41 (98%) male, 37 (88%) White, 14 (33%) with ≥ 10 pack/year smoking history, 40 (95%) check point inhibitor (CPI) naïve (2 received CPI in the adjuvant setting), and 21 (50%) with PD-L1 CPS ≥ 20. HB-200 + pembrolizumab were generally well tolerated. Grade ≥3 treatment-related adverse events (TRAEs) were reported in 6 (14%) patients, serious TRAEs in 3 (7%) patients, and TRAEs leading to treatment discontinuation in 2 (5%) patients. No treatment-related death were reported. Among 35 evaluable patients (those with ≥ 1 tumor response assessments), the overall response rate (ORR) was 43% (3 complete response [CR], 9 partial response [PR], 3 unconfirmed PR) and the disease control rate (DCR) was 71%. Notably, among patients with PD-L1 CPS ≥20 (N = 17), ORR was 59% (3 CR, 6 PR, 1 unconfirmed PR) and DCR was 88%. Conclusions: Updated data of HB-200 arenavirus-based immunotherapy plus pembrolizumab continued to demonstrate a favorable safety profile and promising clinical activity as 1L treatment in patients with HPV16+ PD-L1+ R/M HNSCC and confirms previously reported data. The results suggest that the subgroup of patients with PD-L1 CPS ≥20 may benefit more from this treatment, which warrants further development in a randomized pivotal study. Clinical trial# NCT04180215. Clinical trial information: NCT04180215 .

Population based assessment of HER-2 and PD-L1 positivity in gastric and gastroesophageal junction adenocarcinomas in a Canadian population.

e16038 Background: Current standard of care for advanced gastric and gastroesophageal cancers combines systemic chemotherapy with either human epidermal growth factor receptor 2 (HER-2) or programmed death ligand 1 (PD-L1) targeting therapy. New data is emerging that for patients whose tumours are positive for both HER-2 overexpression and have a PD-L1 combined positive score (CPS) &gt;1%, combining all three treatment modalities results in superior outcomes. There is limited international data, and no Canadian data, exploring the frequency of patients who have tumours that are both HER-2 and PD-L1 positive who will be eligible for this novel treatment approach. Objective: To determine the proportion of patients in Nova Scotia with HER-2 positive gastric and GEJ adenocarcinomas who have a PD-L1 CPS score above established clinical thresholds. Methods: A retrospective review of PD-L1 and HER-2 status for all patients diagnosed with gastric and GEJ adenocarcinomas in Nova Scotia between June 3, 2022 and August 13, 2023 was completed. PD-L1 CPS was evaluated using the 28-8 assay and was considered positive if &gt;1%. HER-2 overexpression was evaluated by immunohistochemistry and in cases with equivocal expression, status was based on fluorescence in situ hybridization. Results: Over the study period, 56 cases of gastric and 42 cases of GEJ adenocarcinoma were identified for a total of 98 cases. The median age of the study population was 73 years (range 38 - 91). 73 patients (74%) were male and 25 patients (26%) were female. HER-2 expression was evaluated in 92 cases, and PD-L1 CPS was evaluated in 95 cases. 19 cases (21%) were HER-2 positive and 86 cases (91%) were PD-L1 positive. 17 HER-2 positive cases were also PD-L1 positive (89%). Conclusions: This study provides population level data in a Canadian context on patients with gastric and GEJ adenocarcinoma with respect to HER-2 overexpression and PD-L1 status. This data will be helpful in planning allocation of clinical and financial resources as a new standard of care for these patients is established.

Abstract PO5-16-07: Unveiling the Landscape of PD-L1 Expression and Tumor-Infiltrating Lymphocyte Subtypes in Advanced Triple-Negative Breast Cancer

Abstract Background: Triple-negative breast cancer (TNBC) is known for its aggressive behavior with poor survival outcomes. Influenced by different expression levels of Programmed Death-Ligand 1 (PD-L1) and several subtypes of tumor-infiltrating lymphocytes (TILs), tumor microenvironment (TME) plays a crucial role in TNBC response to treatment and progression. Objective: To assess the prevalence and prognostic role of PD-L1 expression in advanced TNBC, defined as unresectable stage III or stage IV disease, in patients treated with a standard cytotoxic chemotherapy regimen. TILs composition was also evaluated as an exploratory objective. Methods: The internal database of the Brazilian National Cancer Institute was queried out for women diagnosed and treated with advanced TNBC from January 2018 to December 2022. Formalin-fixed paraffin-embedded samples of a maximum of four years old were analyzed. PD-L1 expression using 22C3 pharmDX assay was estimated through combined positive score (CPS) dichotomization (CPS &amp;lt; 10 vs. CPS≥10). Tissue microarrays comprising the samples of biopsies were subjected to immunohistochemistry, targeting specific markers including CD3, CD4, CD8, CD56, CD68, CD117, FOXP3, PD-1, the immune cell profiles were carefully examined and their correlation with the PD-L1 CPS was determined. Results: A total of 150 patients were included. The expression of PD-L1 was undetermined in 2 cases. The median age was 51.5 years (IQR 41.8-60.2) and 20.9% of the cases had CPS≥10. Most patients were &amp;lt; 65 years (73.0%), were postmenopausal (56.8%) and belonged to non-white ethnicity (70.3%). Postmenopausal women predominated in the CPS≥10 subgroup (74.2%) (Table 1). No significant differences in demographic characteristics and clinicopathological variables were observed based on PD-L1 subgroups, 117 patients (79.1%) had CPS &amp;lt; 10, with 91 (77.8%) being de novo stage IV metastatic disease. CD3+ (p=0.037), CD4+ (p=0.005) and CD8+ (p=0.001) TILs had higher expression in tumors with PD-L1 CPS≥10 (Table 2). According to the treatment received, almost half of the patients only received first-line chemotherapy (47%), as the following second line was applied to 28.8% of the total group. The third and fourth lines were administered in 12.9% and 9.1% of patients, respectively. Only 2 patients went through five palliative chemotherapy lines, and only one received up to 6 treatment lines. Between the subgroups CPS≥10 versus CPS &amp;lt; 10 no statistically significant differences were observed in the median progression-free survival (PFS) (5.1 vs. 5.0 months, p=0.89) and overall survival (OS) (8.7 vs. 8.8 months, p=0.6). Conclusion: This study offers insights into the expression patterns of PD-L1 and TILs subtypes in advanced TNBC cases in Brazil. PD-L1 CPS did not influence survival outcomes for this cohort of patients treated with cytotoxic chemotherapy only. The composition of TILs subtypes within the TME appears to vary based on PD-L1 CPS. Table 1. Advanced TNBC population characteristic by CPS (Nf148). Table 2. Tumor Infiltrating Lymphocytes characterization (CD3, CD4, CD8, CD56, CD68, CD 117, FOXP3 and PD-1) and its correlation with CPS status. Citation Format: Alexssandra Lima Siqueira dos Santos, Jesse Lopes da Silva, Lucas Zanetti de Albuquerque, Antônio Lucas Araújo Neto, Cecília Ferreira da Silva, Luana Aguiar Mesquita Cerva, Isabele Ávila Small, Cicera Pimenta Marcelino, Paula de Mendonça Batista, Maria Aparecida do Carmo Rego, Maria Amélia Carlos Souto Maior Borba, Andreia Cristina de Melo. Unveiling the Landscape of PD-L1 Expression and Tumor-Infiltrating Lymphocyte Subtypes in Advanced Triple-Negative Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-16-07.

Interpretation of PD-L1 expression in gastric cancer: summary of a consensus meeting of Korean gastrointestinal pathologists.

Nivolumab plus chemotherapy in the first-line setting has demonstrated clinical efficacy in patients with human epidermal growth factor receptor 2-negative advanced or metastatic gastric cancer, and is currently indicated as a standard treatment. Programmed death-ligand 1 (PD-L1) expression is an important biomarker for predicting response to anti-programmed death 1/PD-L1 agents in several solid tumors, including gastric cancer. In the CheckMate-649 trial, significant clinical improvements were observed in patients with PD-L1 combined positive score (CPS) ≥ 5, determined using the 28-8 pharmDx assay. Accordingly, an accurate interpretation of PD-L1 CPS, especially at a cutoff of 5, is important. The CPS method evaluates both immune and tumor cells and provides a comprehensive assessment of PD-L1 expression in the tumor microenvironment of gastric cancer. However, CPS evaluation has several limitations, one of which is poor interobserver concordance among pathologists. Despite these limitations, clinical indications relying on PD-L1 CPS are increasing. In response, Korean gastrointestinal pathologists held a consensus meeting for the interpretation of PD-L1 CPS in gastric cancer. Eleven pathologists reviewed 20 PD-L1 slides with a CPS cutoff close to 5, stained with the 28-8 pharmDx assay, and determined the consensus scores. The issues observed in discrepant cases were discussed. In this review, we present cases of gastric cancer with consensus PD-L1 CPS. In addition, we briefly touch upon current practices and clinical issues associated with assays used for the assessment of PD-L1 expression in gastric cancer.

Effectiveness and tolerability of programmed cell death protein-1 inhibitor + chemotherapy compared to chemotherapy for upper gastrointestinal tract cancers.

The combination of programmed cell death protein-1 (PD-1) inhibitor and chemotherapy is approved as a standard first- or second-line treatment in patients with advanced oesophageal or gastric cancer. However, it is unclear whether this combination is superior to chemotherapy alone. To assess the comparative effectiveness and tolerability of combining PD-1 inhibitors with chemotherapy vs chemotherapy alone in patients with advanced gastric cancer, gastroesophageal junction (GEJ) cancer, or oesophageal carcinoma. We searched the PubMed and Embase databases for studies that compared the efficacy and tolerance of PD-1 inhibitors in combination with chemotherapy vs chemotherapy alone in patients with advanced oesophageal or gastric cancer. We employed either random or fixed models to analyze the outcomes of each clinical trial, encompassing data on overall survival (OS), progression-free survival (PFS), objective response rate, and adverse events (AEs). Nine phase 3 clinical trials (7016 advanced oesophageal and gastric cancer patients) met the inclusion criteria. Our meta-analysis demonstrated that the pooled PD-1 inhibitor + chemotherapy group had a significantly longer OS than the chemotherapy-alone group [hazard ratio (HR) = 0.76, 95% confidence interval (CI): 0.71-0.81]; the pooled PFS result was consistent with that of OS (HR = 0.67, 95%CI: 0.61-0.74). The count of patients achieving an objective response in the PD-1 inhibitor + chemotherapy group surpassed that of the chemotherapy-alone group [odds ratio (OR) = 1.86, 95%CI: 1.59-2.18]. AE incidence was also higher in the combination-therapy group than in the chemotherapy-alone group, regardless of whether ≥ grade 3 only (OR = 1.30, 95%CI: 1.07-1.57) or all AE grades (OR = 1.88, 95%CI: 1.39-2.54) were examined. We performed a subgroup analysis based on the programmed death-ligand 1 (PD-L1) combined positive score (CPS) and noted extended OS and PFS durations within the CPS ≥ 1, CPS ≥ 5, and CPS ≥ 10 subgroups of the PD-1 inhibitor + chemotherapy group. In contrast to chemotherapy alone, the combination of PD-1 inhibitor and chemotherapy appears to present a more favorable option for initial or subsequent treatment in patients with gastric cancer, GEJ tumor, or oesophageal cancer. This holds true particularly for individuals with PD-L1 CPS scores of ≥ 5 and ≥ 10.

18F-BMS-986229 PET to Assess Programmed-Death Ligand 1 Status in Gastroesophageal Cancer.

Anti-programmed death 1 (PD-1) inhibitors are the standard of care for advanced gastroesophageal cancer. Although recommendations and approval by regulatory agencies are often based on programmed death ligand 1 (PD-L1) expression, pathologic assessments of PD-L1 status have several limitations. Single-site biopsies do not adequately capture disease heterogeneity within individual tumor lesions or among several lesions within the same patient, the PD-L1 combined positive score is a dynamic biomarker subject to evolution throughout a patient's disease course, and repeated biopsies are invasive and not always feasible. Methods: This was a prospective pilot study of the PD-L1-targeting radiotracer, 18F-BMS-986229, with PET imaging (PD-L1 PET) in patients with gastroesophageal cancer. Patients were administered the 18F-BMS-986229 radiotracer intravenously at a dose of 370 MBq over 1-2 min and underwent whole-body PET/CT imaging 60 min later. The primary objective of this study was to evaluate the safety and feasibility of 18F-BMS-986229. The trial is registered with ClinicalTrials.gov (NCT04161781). Results: Between February 3, 2020, and February 2, 2022, 10 patients with gastroesophageal adenocarcinoma underwent PD-L1 PET. There were no adverse events associated with the 18F-BMS-986229 tracer, and imaging did not result in treatment delays; the primary endpoint was achieved. Radiographic evaluation of PD-L1 expression was concordant with pathologic assessment in 88% of biopsied lesions, and 18F-BMS-986229 uptake on PET imaging correlated with pathologic evaluation by the combined positive score (Spearman rank correlation coefficient, 0.64). Seventy-one percent of patients with 18F-BMS-986229 accumulation on PET imaging also had lesions without 18F-BMS-986229 uptake, highlighting the intrapatient heterogeneity of PD-L1 expression. Patients treated with frontline programmed death 1 inhibitors who had 18F-BMS-986229 accumulation in any lesions on PET imaging had longer progression-free survival than patients without tracer accumulation in any lesions (median progression-free survival, 28.4 vs. 9.9 mo), though the small sample size prevents any definitive conclusions. Conclusion: PD-L1 PET imaging was safe, feasible, and concordant with pathologic evaluation and offers a potential noninvasive tool to assess PD-L1 expression.

HER2 and PD-L1 Expression in Gastric and Gastroesophageal Junction Cancer: Insights for Combinatorial Targeting Approaches.

Gastric and gastroesophageal junction adenocarcinomas (GA/GEJA) are associated with a poor prognosis, primarily due to late disease diagnosis. Human Epidermal Growth Factor Receptor 2 (HER2) overexpression and programmed death-ligand 1 (PD-L1) expression are important biomarkers for treatment selection in locally advanced unresectable and metastatic GA/GEJA, and there is increasing interest in their role in earlier stages of disease. In this study, we aimed to evaluate HER2 and PD-L1 expression in a curative-intent GA/GEJA cohort to describe their expression patterns and analyze the association between HER2 expression and clinicopathological features. HER2 expression was evaluated in surgical and endoscopic submucosal dissection tumor samples, and PD-L1 was evaluated in HER2-positive cases. The clinical cohort included 107 patients, with 8.4% testing positive for HER2 (seven of whom also exhibited a PD-L1 combined positive score of ≥1. HER2 status was not significantly associated with survival outcomes. A pathologist-guided, region-specific analysis revealed that PD-L1 expression rarely overlaps with HER2-positive tumor areas. While the therapeutic implications of these observations remain unknown, these findings suggest that combination strategies targeting HER2 and PD-L1 might be directed toward distinct tumor subclones. The herein disclosed region-specific biomarker expression patterns may have important therapeutic and prognostic impacts, warranting further evaluation.

Whole-transcriptome sequencing in advanced gastric or gastroesophageal cancer: A deep dive into its clinical potential.

Advanced gastric and gastroesophageal junction cancers (GC/GEJCs) harbor diverse molecular signatures, highlighting the need for intricate evaluations to identify potential therapeutic targets. Although whole-transcriptome sequencing (WTS) has emerged as a useful tool for understanding these molecular intricacies, its clinical implications have yet to be fully elucidated. This study evaluated the correlation between immunohistochemistry (IHC) and WTS, compared their clinical significance, and identified potential therapeutic targets undetectable through IHC alone. We enrolled 140 patients with advanced GC/GEJC and assessed them using IHC for six pivotal biomarkers: claudin-18 (CLDN18), human epidermal growth factor receptor 2 (HER2), multiple receptor tyrosine kinases (RTKs), and programmed death ligand 1 (PD-L1). Concurrently, WTS was employed as part of the analyses in MONSTAR-SCREEN-2, a multicenter multiomics study. IHC analysis revealed 16.4% HER2, 39.3% CLDN18 (2+/3 + ≥75%), and 15.8% PD-L1 (combined positive score ≥ 10) positivity, among other molecular markers. Significant correlations were observed between IHC and WTS for all six pivotal biomarkers. Among nineteen HER2 IHC-positive patients treated with anti-HER2 therapeutics, ERBB2 status in WTS was significantly associated with progression-free survival (ERBB2-high vs. -low: median 9.0 vs. 5.6 months, log-rank p = 0.046). IHC-based molecular profiling revealed significantly high expression of CLDN18 in RTK-negative patients, with 78.4% positive for either CLDN18 or PD-L1. Additionally, WTS revealed elevated expression of pivotal biomarkers in patients displaying negative targetable biomarkers via IHC. Our findings highlighted the significant correlation between IHC and WTS, reinforcing the clinical utility of WTS. A subset with IHC-negative but WTS-positive status may benefit from specific biomarker-targeted therapies.

First-line (1L) nivolumab (NIVO) plus chemotherapy (chemo) vs chemo in patients (pts) with advanced gastric cancer, gastroesophageal junction cancer, and esophageal adenocarcinoma (GC/GEJC/EAC): CheckMate 649 Chinese subgroup analysis 4-year (yr) follow-up.

318 Background: NIVO + chemo demonstrated clinically meaningful improvement in overall survival (OS) and an acceptable safety profile vs chemo in previously untreated Chinese pts from CheckMate 649, consistent with the overall study population with advanced GC/GEJC/EAC. 1L NIVO + chemo is approved for advanced GC/GEJC/EAC in multiple countries, including China. We report 4-yr results of NIVO + chemo vs chemo in Chinese pts from CheckMate 649. Methods: Adults with previously untreated, unresectable advanced or metastatic, non-HER2+ GC/GEJC/EAC were enrolled regardless of programmed death ligand 1 (PD-L1) expression. Randomized pts received NIVO (360 mg Q3W or 240 mg Q2W) + chemo (XELOX Q3W or FOLFOX Q2W), NIVO + ipilimumab, or chemo. Dual primary endpoints for NIVO + chemo vs chemo were OS and progression-free survival (PFS) by blinded independent central review (BICR) in pts with PD-L1 combined positive score (CPS) ≥ 5. Results: 208 Chinese pts were randomized to NIVO + chemo or chemo. At 49-month (mo) minimum follow-up, NIVO + chemo continued to demonstrate OS and PFS benefit vs chemo in pts with PD-L1 CPS ≥ 5 and in all randomized pts (Table). The 4-yr OS rate was 25% with NIVO + chemo vs 11% with chemo in pts with PD-L1 CPS ≥ 5 and 21% vs 9% in all randomized pts. Objective response rate (ORR; 95% CI) per BICR in pts with PD-L1 CPS ≥ 5 who had measurable lesions at baseline was 68% (56–79) with NIVO + chemo vs 48% (36–60) with chemo; corresponding ORR in all randomized pts was 66% (55–76) and 45% (35–56). Responses were more durable with NIVO + chemo vs chemo both in pts with PD-L1 CPS ≥ 5 (median duration of response [mDOR; 95% CI] 12.5 mo [7.2–23.4] vs 6.9 mo [3.9–8.5]) and in all randomized pts (mDOR [95% CI] 12.5 mo [7.2–17.7] vs 5.6 mo [4.4–8.3]). No new safety signals were identified (Table). Conclusions: After 4 yrs of follow-up, NIVO + chemo continued to demonstrate clinically meaningful survival benefit and more durable responses vs chemo in Chinese pts, with an acceptable safety profile. These results are consistent with previous reports and with the overall study population with advanced GC/GEJC/EAC and further support NIVO + chemo as a standard 1L treatment option for Chinese pts. Clinical trial information: NCT02872116 . [Table: see text]

Nivolumab (NIVO) + chemotherapy (chemo) vs chemo as first-line (1L) treatment for advanced gastric cancer/gastroesophageal junction cancer/esophageal adenocarcinoma (GC/GEJC/EAC): 4 year (yr) follow-up of CheckMate 649.

306 Background: NIVO + chemo demonstrated superior overall survival (OS) and clinically meaningful progression-free survival (PFS) benefit vs chemo and an acceptable safety profile in previously untreated, advanced non-HER2+ GC/GEJC/EAC, leading to approvals in many countries. NIVO + chemo continued to demonstrate clinically meaningful improvement in efficacy at 2 and 3-yr follow-ups. We present 4-yr follow-up results for NIVO + chemo vs chemo from CheckMate 649. Methods: Adults with previously untreated, unresectable advanced, or metastatic GC/GEJC/EAC were enrolled, regardless of programmed death ligand 1 (PD-L1) expression. HER2+ patients (pts) were excluded. Randomized pts received NIVO (360 mg Q3W or 240 mg Q2W) + chemo (XELOX Q3W or FOLFOX Q2W), NIVO + ipilimumab, or chemo. Dual primary endpoints for NIVO + chemo vs chemo were OS and PFS by blinded independent central review (BICR) in pts with PD-L1 combined positive score (CPS) ≥ 5. Results: 1581 pts were randomized to NIVO + chemo or chemo. At the 48-month (mo) minimum follow-up, NIVO + chemo continued to demonstrate OS and PFS benefit vs chemo in pts with PD-L1 CPS ≥ 5 and all randomized pts (Table) OS benefit with NIVO + chemo was observed in most prespecified subgroups. Objective response rates (ORR) were higher and responses were more durable with NIVO + chemo vs chemo in pts with PD-L1 CPS ≥ 5 and all randomized pts (Table). In the exploratory analysis of OS by response at the 18-week landmark timepoint, there were numerically more pts achieving response with NIVO + chemo vs chemo, and median OS (95% CI) with NIVO + chemo was numerically longer in responders vs non-responders both in pts with PD-L1 CPS ≥ 5 (20.5 [17.5–25.0] vs 14.0 [11.6–15.7]) and all randomized pts (19.4 [17.5–21.7] vs 13.1 [11.6–14.4]). No new safety signals were identified, consistent with the 3-yr follow-up. Conclusions: NIVO + chemo is the first PD-1 inhibitor/chemo combination to demonstrate long-term efficacy and acceptable safety after 4 yrs of follow up in previously untreated advanced GC/GEJC/EAC. These results are consistent with earlier follow-ups, further supporting NIVO + chemo as a standard 1L treatment in these pts. Clinical trial information: NCT02872116 .[Table: see text]

Expression and clinicopathologic significance of HER2 and PD-L1 in high grade urothelial carcinoma of the urinary tract.

Urothelial carcinoma (UC) is an aggressive tumor with high recurrence rates and poses a great challenge for clinical management. Programmed death ligand-1 (PD-L1) inhibitors and human epidermal growth factor receptor 2 (HER2) blockers have been approved for the treatment of advanced urothelial carcinoma. PD-L1 and HER2 expression in UC will determine whether patients are likely to respond to these targeted treatments. This study assessed the expressions of HER2 and PD-L1 in UC at our institution and investigated their correlations with gender, tumor location (upper genitourinary (GU) tract vs. lower GU tract), tumor stage, and histologic divergent subtypes. Patients with UC who had PD-L1 or HER2 immunostains performed in the past 3 years at our institution were included in our analysis. A total of 97 cases were identified. PD-L1 and HER2 scores were provided by two experienced GU pathologists. HER2 scores were given according to the criteria used in breast cancer, while PD-L1 scores were reported as the combined positive score. We assessed correlation of the scores with the patients' gender, tumor location, tumor stage, and histologic divergent subtypes. The data for PD-L1 expression were analyzed using the Mann-Whitney U Test for gender and urinary tract location, and one-way analysis of variance (ANOVA) for stage and histology. The data for HER2 expression were analyzed using the chi-square test. For all analyses, significance was set at P<0.05. Of the 97 patients, the average age was 69 years. There were 95 patients who had previously reported HER2 results and 86 patients who had PD-L1 results. PD-L1 expression did not show a significant difference among the histological divergent subtypes (P=0.36). However, HER2 status exhibited a significant difference, with more HER2-positive cases observed in the conventional histology (P=0.008). No correlation between HER2 status and either gender or tumor stage was identified. The median PD-L1 combined positive score was significantly higher in lower urinary tract UC than upper (10 and 2, respectively; P=0.049). No significant differences were observed for gender or pathologic stage. Our data suggest that HER2 is more frequently expressed in conventional UC than in divergent subtypes. Additionally, PD-L1 has a higher expression level in lower urinary tract UC compared to upper. However, PD-L1 and HER2 expression are not related to gender or tumor stage in UC.