Programmed death ligand-1 expression in non-small cell lung cancer in a Western Australian population and correlation with clinicopathologic features

Real-world prevalence of PD-L1 expression in non-small cell lung cancer: an Australia-wide multi-centre retrospective observational study

An investigator-initiated, Australia-wide multi-centre retrospective observational study was undertaken to investigate the real-world prevalence of programmed death ligand-1 (PD-L1) expression in non-small cell lung carcinoma (NSCLC). Multiple centres around Australia performing PD-L1 immunohistochemistry (IHC) were invited to participate. Histologically confirmed NSCLC of any stage with a PD-L1 IHC test performed for persons aged ≥18 years between 1 January 2018 and 1 January 2020, and eligible for review, were identified at each centre, followed by data extraction and de-identification, after which data were submitted to a central site for collation and analysis. In total data from 6690 eligible PD-L1 IHC tests from histologically (75%) or cytologically (24%) confirmed NSCLC of any stage were reviewed from persons with a median age of 70 years, 43% of which were female. The majority (81%) of tests were performed using the PD-L1 IHC SP263 antibody with the Ventana BenchMark Ultra platform and 19% were performed using Dako PD-L1 IHC 22C3 pharmDx assay. Reported PD-L1 tumour proportion score (TPS) was ≥50% for 30% of all tests, with 62% and 38% scoring PD-L1 ≥1% and <1%, respectively. Relative prevalence of clinicopathological features with PD-L1 scores dichotomised to <50% and ≥50%, or to <1% and ≥1%, were examined. Females scored ≥1% slightly more often than males (64% vs 61%, respectively, p=0.013). However, there was no difference between sexes or age groups (<70 or ≥70 years) where PD-L1 scored ≥50%. Specimens from patients with higher stage (III/IV) scored ≥1% or ≥50% marginally more often compared to specimens from patients with lower stage (I/II) (p≤0.002). Proportions of primary and metastatic specimens did not differ where PD-L1 TPS was ≥1%, however more metastatic samples scored TPS ≥50% than primary samples (metastatic vs primary; 34% vs 27%, p<0.001). Cytology and biopsy specimens were equally reported, at 63% of specimens, to score TPS ≥1%, whereas cytology samples scored TPS ≥50% slightly more often than biopsy samples (34% vs 30%, respectively, p=0.004). Resection specimens (16% of samples tested) were reported to score TPS ≥50% or ≥1% less often than either biopsy or cytology samples (p<0.001). There was no difference in the proportion of tests with TPS ≥1% between PD-L1 IHC assays used, however the proportion of tests scored at TPS ≥50% was marginally higher for 22C3 compared to SP263 (34% vs 29%, respectively, p<0.001). These real-world Australian data are comparable to some previously published global real-world data, with some differences noted.

[Research Progress of Anti-PD-1/PD-L1 Therapy for Non-small Cell Lung Cancer with EGFR Mutation]

The use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) is the first line treatment for EGFR-mutant advanced non-small cell lung cancer (NSCLC), but drug resistance will be acquired within 1-2 years, and the following treatment efficacy is poor. The invention of programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) inhibitors has dramatically changed the situation of tumor treatment. PD-1/PD-L1 inhibitors are less effective in patients with NSCLC harboring EGFR mutation. It is a challenge to make patients with EGFR-mutated advanced NSCLC benefit from anti-PD-1/PD-L1 therapy. In this paper, the research progress on the impact of EGFR mutation on the immune status of NSCLC and related clinical studies in recent 5 years are reviewed.
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EGFR mutation status in non-small cell lung cancer receiving PD-1/PD-L1 inhibitors and its correlation with PD-L1 expression: a meta-analysis

Meta-analysis was performed on the Web of Science, PubMed, Embase, and Cochrane databases to evaluate the effect of epidermal growth factor receptor (EGFR) mutation status on programmed cell death protein 1/programmed death ligand 1 (PD-1/PD-L1) immune checkpoint inhibitors, and the association between EGFR mutation status and PD-L1 expression in non-small cell lung cancer (NSCLC) patients. Pooled effect (hazard ratio/odds ratio, HR/OR) with 95% confidence interval (CI) was calculated, and the source of heterogeneity was explored by subgroup analysis and meta-regression using Stata/SE 15.0. Meta-analysis of the association between EGFR mutation status and overall survival (OS) in NSCLC with immunotherapy was calculated from four randomized controlled trials. We found that immune checkpoint inhibitors significantly prolonged OS over docetaxel overall (HR 0.71, 95% CI 0.64-0.79) and in the EGFR wild type (HR = 0.67, 95% CI = 0.60-0.75), but not in the EGFR mutant subgroup (HR = 1.11, 95% CI = 0.80-1.52). Meta-analysis of the association between EGFR mutation status and PD-L1 expression in NSCLC included 32 studies. The pooled OR and 95% CI were 0.60 (0.46-0.80), calculated by random effects model. No source of heterogeneity was found in subgroup analysis. Sensitivity analysis was carried out with a fixed model, and the influence of a single study on the pooled results showed no significant change with robust meta-analysis methods. Harbord's weighted linear regression test (P = 0.956) and Peters regression test (P = 0.489) indicated no significant publication bias. The limited benefit of single-agent PD-1/PD-L1 inhibitors in the second-line or later setting for EGFR-mutated NSCLC may be partly due to the lower expression of PD-L1.

Study on PD-L1 Expression in NSCLC Patients and Related Influencing Factors in the Real World

PD-L1 is one of the current biomarkers for immune checkpoint inhibitor (ICI) therapy in patients with non-small-cell lung cancer. However, the expression of PD-L1 in the real world and its related influencing factors remain unclear. We want to observe the expression of PD-L1 in the real world and study the related influencing factors through the collection and analysis of clinical data. R software (version 4.0) was used to perform data analysis and the “corplot” package for correlation analysis. A total of 296 individuals (mean [SD] age, 67 [9] years; 23%female) were assessed. According to the expression amount of PD-L1, the cohort was divided into low nonexpression group (PD‐L1 < 1%, 26.7%), low-expression group (1% ≤ PD‐L1 < 50%, 49.3%), and high-expression group (PD‐L1 ≥ 50%, 23.5%). Age, gender, underlying diseases, smoking status, and PD-L1 expression level were not statistically significant. We found that the expression of PD-L1 was correlated with serum albumin (P < 0.05) and pathological type (P < 0.05) and had a negative correlation with EGFR mutation but did not correlate with gender, age, smoking status, combined with underlying diseases, tumor stage, whether it was initially treated or not, sampling site, specimen type, specimen storage time, R-IFN, CD4, CD8, NLR, CRP, and LDH. The present findings indicated that serum albumin, pathological type, and EGFR mutations are associated with PD-L1 expression in patients with NSCLC, which may provide a new basis for individualized immunotherapy and need further study to confirm. The results of this study help to further reveal the actual expression of PD-L1 in non-small-cell lung cancer patients with real events.

Programmed death-ligand 1 expression and its associations with clinicopathological features, prognosis, and driver oncogene alterations in surgically resected lung adenocarcinoma

OBJECTIVES

Programmed death-ligand 1 (PD-L1) expression is a predictive biomarker of response to immunotherapies targeting programmed death-1/PD-L1 in advanced-stage lung adenocarcinoma. The aim of this study was to investigate the associations between PD-L1 expression and clinicopathological features, prognosis, and driver oncogene alterations in patients with lung adenocarcinoma.

MATERIALS AND METHODS

We evaluated PD-L1 expression in 1,005 surgically resected lung adenocarcinoma specimens, by immunohistochemistry using the 22C3 antibody. PD-L1 positivity was defined based on the proportion of stained tumor cells (TPS) on tissue microarrays: <1% (negative), 1-49% (weakly positive), and ≥ 50% (strongly positive). Correlations between PD-L1 expression and clinicopathological features, prognosis, and driver oncogene (EGFR, KRAS, ALK, ROS1, and RET) alterations in lung adenocarcinoma were analyzed.

RESULTS

PD-L1 expression was negative in 726 (72%) of 1,005 tumors, weakly positive in 161 (16%), and strongly positive in 118 (12%). Male sex, smoking, elevated serum carcinoembryonic antigen levels, advanced pathological stages, high-grade tumors, predominantly solid tumors, tumors with lymphatic permeation or vascular or pleural invasion, tumors without EGFR mutations, and tumors with KRAS mutations were more common in patients with PD-L1-positive tumors (TPS ≥ 1%) than in those with PD-L1-negative tumors (TPS < 1%). PD-L1 positivity was not associated with ALK, ROS1, or RET fusion status. Although PD-L1 positivity was associated with poor overall survival and poor relapse-free survival in all patients, this was not statistically significant after adjusting for prognostic factors in the multivariate analysis. In the subgroup analysis according to driver oncogene alterations, PD-L1 positivity was associated with poor relapse-free survival only in patients with EGFR-mutated tumors.

CONCLUSION

Surgically resected lung adenocarcinomas with increased PD-L1 expression were biologically aggressive tumors that frequently occurred in male smokers. PD-L1 expression and its prognostic significance differed according to driver oncogene alterations.

Considerable interlaboratory variation in PD-L1 positivity in a nationwide cohort of non-small cell lung cancer patients

OBJECTIVES

Immunohistochemical expression of programmed death-ligand 1 (PD-L1) is used as a predictive biomarker for prescription of immunotherapy to non-small cell lung cancer (NSCLC) patients. Accurate assessment of PD-L1 expression is therefore crucial. In this study, the extent of interlaboratory variation in PD-L1 positivity in the Netherlands was assessed, using real-world clinical pathology data.

MATERIALS AND METHODS

Data on all NSCLC patients in the Netherlands with a mention of PD-L1 testing in their pathology report from July 2017 to December 2018 were extracted from PALGA, the nationwide network and registry of histo- and cytopathology in the Netherlands. PD-L1 positivity rates were determined for each laboratory that performed PD-L1 testing, with separate analyses for histological and cytological material. Two cutoffs (1% and 50%) were used to determine PD-L1 positivity. Differences between laboratories were assessed using funnel plots with 95% confidence limits around the overall mean.

RESULTS

6,354 patients from 30 laboratories were included in the analysis of histology data. At the 1% cutoff, maximum interlaboratory variation was 39.1% (32.7%-71.8%) and ten laboratories (33.3%) differed significantly from the mean. Using the 50% cutoff, four laboratories (13.3%) differed significantly from the mean and maximum variation was 23.1% (17.2%-40.3%). In the analysis of cytology data, 1,868 patients from 23 laboratories were included. Eight laboratories (34.8%) differed significantly from the mean in the analyses of both cutoffs. Maximum variation was 41.2% (32.2%-73.4%) and 29.2% (14.7%-43.9%) using the 1% and 50% cutoffs, respectively.

CONCLUSION

Considerable interlaboratory variation in PD-L1 positivity was observed. Variation was largest using the 1% cutoff. At the 50% cutoff, analysis of cytology data demonstrated a higher degree of variation than the analysis of histology data.

HNRNPL affects the proliferation and apoptosis of colorectal cancer cells by regulating PD-L1

Colorectal cancer (CRC) ranks fourth among all human cancers in the world. HNRNPL plays an oncogenic role in various cancers, but is not discussed yet in CRC. The presents study aims to investigate the role of HNRNPL in CRC development. The mRNA and protein levels of HNRNPL in CRC cells were measured by RT-qPCR and western blot. The cell viability, colony formation, and apoptosis were evaluated after CRC cells were transfected with shRNA-HNRNPL. Also, the invasion and migration of transfected cells were respectively detected by transwell and wound-healing assays. Besides, tumor-bearing mice were established after C57BL/6 mice received injection of CRC cells with or without overexpression plasmid of HNRNPL, accompanied with anti-PD-L1 treatment. Expression of Ki67 in tumor tissue was detected using immunohistochemistry. HNRNPL was up-regulated in CRC cells, and transfection with shRNA-HNRNPL led to the decreases in cell viability, migration, invasion, and the increase in apoptosis of CRC cells. HNRNPL was verified to be a potential binding protein of PD-L1. Overexpression of HNRNPL promoted tumor growth in vivo, which was attenuated by anti-PD-L1 treatment. HNRNPL promotes the tumor growth and development of CRC by regulating PD-L1, which may direct us a new method to treat CRC.

Distribution and Expression of Programmed Death Ligand -1 (PD-L1) in Non-Small Cell Carcinomas of the Lung in a Tertiary Care Centre in South India

OBJECTIVE

Non-small cell lung carcinomas often present at an advanced stage with a grim prognosis. Immune checkpoint (ICP) inhibitors have drastically changed the scenario, and the response to ICP inhibitors is determined by analyzing the expression of PD-L1 by immunohistochemistry. PD-L1 immunohistochemistry helps in optimizing the treatment, and avoiding unnecessary exposure of patients to the toxic effects of the drugs that are ineffective and expensive in non-expressing tumors. This study was conducted to assess the prevalence of the expression of PD-L1 in non-small cell carcinomas of the lung diagnosed at our institution, which is a tertiary care center in South India.

MATERIAL AND METHOD

The PD-L1 immunohistochemistry of 77 cases of non-small cell carcinomas of the lung diagnosed over a period of two years were reviewed and analyzed (2018-2020). All tissues were fixed in 10% neutral buffered formalin and processed by standard methods, and the Ventana SP263 clone was used.

RESULTS

Seventy-seven cases of non-small cell lung carcinomas were reviewed and studied for (PD-L1) expression. 35/77 (45%) of the cases had PD-L1 expression (≥ 1%) and 14 (18 %) had high (PD-L1) expression. Also there was a male preponderance of 2.3:1. High PD-L1 expression was seen mostly in patients above 60 years of age and was usually associated with high tumor grade.

CONCLUSION

It is important to assess PD-L1 expression in non-small cell carcinomas of patients especially with higher tumor grade and older age groups that they may benefit from immune checkpoint inhibitor therapy.

Real-world programmed death-ligand 1 prevalence rates in non-small cell lung cancer: correlation with clinicopathological features and tumour mutation status

AIMS

The detection of programmed death-ligand 1 (PD-L1) protein expression on tumour cells by immunohistochemistry (IHC) is a predictor of response to immune checkpoint inhibitors. New immunotherapeutic options are changing the treatment paradigm for patients with advanced non-small cell lung cancer (NSCLC). The aim of this retrospective study was to investigate real-world prevalence of PD-L1 expression in NSCLC and any correlations with clinicopathological features.

METHODS

We reviewed 425 NSCLC cases at a Sydney metropolitan hospital that had PD-L1 IHC (SP263 clone) expression estimated as part of routine diagnostic assessment during a 30-month period.

RESULTS

Overall, 32.2% of cases were negative for PD-L1 expression (<1%), 40.3% demonstrated low expression (1%-49%) and 27.5% exhibited high protein expression (≥50%). High PD-L1 expression rates were more likely in non-lung resection cases and in KRAS mutant NSCLC as opposed to KRAS wildtype, while lower expression rates were more commonly found in EGFR mutant NSCLC compared with EGFR wildtype tumours.

CONCLUSIONS

Ongoing observation and comparison of PD-L1 expression rates is an important practice for ensuring its validity as a predictive biomarker. The results from our study align with and contribute to the growing field of published real-world PD-L1 prevalence rates in NSCLC.

PD-L1 Expression on Circulating Tumor Cells May Be Predictive of Response to Pembrolizumab in Advanced Melanoma: Results from a Pilot Study

BACKGROUND

PD-1 inhibitors are routinely used for the treatment of advanced melanoma. This study sought to determine whether PD-L1 expression on circulating tumor cells (CTCs) can serve as a predictive biomarker of clinical benefit and response to treatment with the PD-1 inhibitor pembrolizumab.

METHODS

Blood samples were collected from patients with metastatic melanoma receiving pembrolizumab, prior to treatment and 6-12 weeks after initiation of therapy. Multiparametric flow cytometry was used to identify CTCs and evaluate the expression of PD-L1.

RESULTS

CTCs were detected in 25 of 40 patients (63%). Patients with detectable PD-L1+ CTCs (14/25, 64%) had significantly longer progression-free survival (PFS) compared with patients with PD-L1- CTCs (26.6 months vs. 5.5 months; p = .018). The 12-month PFS rates were 76% versus 22% in the PD-L1+ versus PD-L1- CTCs groups (p = .012), respectively. A multivariate linear regression analysis confirmed that PD-L1+ CTC is an independent predictive biomarker of PFS (hazard ratio, 0.229; 95% confidence interval, 0.052-1.012; p = .026).

CONCLUSION

Our results reveal the potential of CTCs as a noninvasive real-time biopsy to evaluate PD-L1 expression in patients with melanoma. PD-L1 expression on CTCs may be predictive of response to pembrolizumab and longer PFS.

IMPLICATIONS FOR PRACTICE

The present data suggest that PD-L1 expression on circulating tumor cells may predict response to pembrolizumab in advanced melanoma. This needs further validation in a larger trial and, if proven, might be a useful liquid biopsy tool that could be used to stratify patients into groups more likely to respond to immunotherapy, hence leading to health cost savings.

The prevalence of programmed death ligand-1 (PD-L1) expression in non-small cell lung cancer in an unselected, consecutive population

Little is known about prevalence of PD-L1 expression in tumor cells of unselected patients with all stages of non-small cell lung cancer. The objective of this study is to assess the prevalence of PD-L1 positivity in patients with non-small cell lung cancer, to analyze the association between PD-L1 positivity and patients' clinicopathological characteristics, and to assess the use of immune-oncologic treatment in eligible patients. All non-small cell lung cancer patients diagnosed in a 10-month period in an unselected population of 1.7 million Caucasian inhabitants were evaluated with the PD-L1 IHC 22C3 pharmDx kit. A total of 819 patients were diagnosed with non-small cell lung cancer. Samples analyzable for PD-L1 expression were obtained from 97% of patients. In a multivariate analysis with cut-off at tumor proportion score ≥50%, lower stage was associated with lower prevalence of PD-L1 positivity with an odds ratio of 0.31 for stage I vs. stage IV. A significant difference in PD-L1 expression between squamous-cell carcinoma and adenocarcinoma was observed with odds ratio for adenocarcinoma 1.8. With cut-off tumor proportion score ≥1%, attenuated effects of the same direction were seen. For neither cut-off did type and location of material used for PD-L1 analysis, age, sex, smoking history, or performance status have statistically significant impact on the PD-L1 expression. Fifty four percent of the patients who were eligible for immune-oncologic treatment were actually treated in first-line with pembrolizumab monotherapy. In conclusion, 97% of the patients had material analyzable for PD-L1. If a patient in need of immuno-oncologic treatment has shifted stage, a negative or low positive PD-L1 test performed on a biopsy taken in a lower stage might not mirror the PD-L1 expression in the new metastatic lesion. Therefore, a re-biopsy should be considered.

PD-L1 expression on tumor-infiltrating immune cells is highly associated with M2 TAM and aggressive malignant potential in patients with resected non-small cell lung cancer

OBJECTIVES

PD-L1 expression on tumor cells (TCs) and tumor-infiltrating immune cells (ICs) plays important roles in regulating the antitumor T cell response. However, the mechanistic and clinical significance of the effect of PD-L1 on TCs versus ICs remains unclear. On the other hand, tumor-associated macrophages (TAMs), M2 macrophages in particular, can promote tumor progression.

METHODS

We evaluated PD-L1 expression on TCs and ICs using Ventana SP263 assay and the stromal M2 TAM distribution using CD163 staining in 160 consecutive patients with resected non-small cell lung cancer (NSCLC).

RESULTS

PD-L1 expression on TCs and ICs was significantly higher in stromal M2 TAM-high group than in stromal M2 TAM-low group (p < 0.001 and p < 0.001, respectively). Regarding the clinical significance of PD-L1, PD-L1 expression on TCs was significantly associated with histology (p = 0.001), tumor differentiation (p < 0.001) and nodal status (p = 0.029). Furthermore, PD-L1 expression on ICs was significantly associated with histology (p < 0.001), tumor differentiation (p < 0.001), tumor status (p = 0.024), nodal status (p = 0.016), and pathologic stage (p = 0.004). The disease-free survival rate was significantly lower in patients with PD-L1-positive TC than in those with PD-L1-negative TC (p = 0.023), as well as in patients with PD-L1-positive IC than in those with PD-L1-negative IC (p < 0.001). Furthermore, the overall survival rate was significantly lower in patients with PD-L1-positive IC than in those with PD-L1-negative IC (p = 0.023).

CONCLUSIONS

During tumor progression in NSCLC, the presence of M2 TAMs might affect PD-L1 expression both on TCs and ICs. In patients with NSCLC, PD-L1 expression both on TCs and ICs was associated with malignant behaviors, which was more in case of ICs.

Programmed cell death ligand 1 expression in cytologic and surgical non-small cell lung carcinoma specimens from a single institution: Association with clinicopathologic features and molecular alterations

BACKGROUND

Programmed cell death ligand 1 (PD-L1) expression by the 22C3 pharmDx companion assay has been validated in surgical specimens to support pembrolizumab treatment decisions for patients with non-small cell lung carcinoma (NSCLC). The aims of this study were 1) to assess the adequacy of cytologic specimens for PD-L1 evaluation and 2) to explore correlations of PD-L1 expression with clinicopathologic and molecular features.

METHODS

The study cohort included 100 cytology specimens (fluid [n = 28] and fine-needle aspiration [n = 72]) and 165 surgical specimens (biopsy [n = 138] and resection [n = 27]). The PD-L1 immunohistochemistry 22C3 assay and staining assessment were performed according to the manufacturer's instructions. PD-L1 expression was correlated with patients' demographics, pathologic characteristics, and molecular alterations.

RESULTS

One hundred forty-two specimens (53.6%) were positive for PD-L1 expression (≥1%). No statistically significant difference in PD-L1 expression was identified between cytologic (56.0%) and surgical specimens (52.1%). Seventy-four of 190 tested cases (38.9%) had genetic alterations. PD-L1 positivity was significantly more prevalent in cases with genetic alterations than in cases without genetic alterations. Furthermore, both PD-L1 positivity and high PD-L1 expression (≥50%) had statistically significant associations with Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. PD-L1 expression had no significant association with histologic phenotypes or other clinicopathologic features.

CONCLUSIONS

The data indicate that cytologic specimens are comparable to surgical specimens for PD-L1 evaluation. The association of PD-L1 expression with KRAS mutations may have clinical relevance in selecting patients with NSCLC for immunotherapy.