Effectivity and safety of PD-1/PD-L1 inhibitors for different level of PD-L1-positive, advanced NSCLC: A meta-analysis of 4939 patients from randomized controlled trials

Effects of EGFR driver mutations on pathologic regression in resectable locally advanced non-small cell lung cancer treated with neoadjuvant chemoradiation and completion surgery

OBJECTIVE

We hypothesized that driver mutations in epidermal growth factor receptor (EGFR) are associated with decreased pathologic response to neoadjuvant chemoradiation (NA-ChRT) in locally advanced non-small cell lung cancer (LA-NSCLC).

METHODS

Patients with Stage IIB-IIIA NSCLC treated with NA-ChRT, completion surgery, and underwent molecular profile testing were identified in a lung cancer database. Pathologic response was quantified using: (i) major pathologic response (MPR), (ii) complete pathologic response (pCR), and (iii) mean residual viable tumor cells (MRTC). Two groups were formed based on the presence or absence of driver mutations. Clinical and pathological correlations between the groups were studied.

RESULTS

Forty-seven patients underwent tumor molecular profile testing, NA-ChRT, and completion surgery. Compared to the no-driver mutation group, the driver mutation group had lower MPR (23% vs 71%, p = 0.003), pCR (0% vs 26%, p = 0.02), and higher MRTC (43.4% vs 15.8%, p = 0.009). Univariate analysis showed an increased MPR rate for smokers, squamous cell histology, ChRT-surgery interval >65 days, and no-driver mutations. Multivariate analysis showed that only no-driver mutations (OR 0.39, p = 0.02) remained significant for MPR. PD-L1 status did not affect MPR. At 2 years, the driver mutation group had lower rates of local control (Hazard ration [HR] 0.67, p = 0.17) and disease-free survival (HR 0.5, p = 0.001). Overall survival was similar for both groups (HR = 1.04, p = 0.86).

CONCLUSION

Following 60 Gray NA-ChRT, tumors with a driver mutation had lower MPR and pCR rates than tumors without a driver mutation. PD-L1 was not associated with tumor regression.

ADVANCES IN KNOWLEDGE

Patients with resectable LA-NSCLC and an EGFR driver mutation treated with neoadjuvant-ChRT and completion surgery have reduced pathologic regression, lower local control rates, and shorter disease-free survival than patients without a driver mutation. Evaluation of molecular testing should be introduced in LA-NSCLC intended for prognostication and treatment decisions.

Immunomodulatory functions of the circ_001678/miRNA-326/ZEB1 axis in non-small cell lung cancer via the regulation of PD-1/PD-L1 pathway

High-throughput circRNA sequencing identified circRNA_001678 (circ_001678) as an upregulated circRNA in NSCLC tissues. Hence, the current study sought to investigate the function and the underlying mechanism of circRNA_001678 in immune escape of NSCLC. Briefly, commercially purchased NSCLC cell lines were adopted for in vitro experiment to evaluate the effects of circ_001678 over-expression or knockdown on cell biological functions, including proliferation, migration, and invasive abilities. In addition, the effects of circ_001678 on the in vivo tumorigenicity ability were evaluated for verification. Accordingly, we uncovered that circ_001678 over-expression augmented NSCLC progression in vitro and enhanced tumorigenicity ability in vivo. The interaction between circ_001678 and miR-326 predicted online was verified by means of luciferase and RNA pull-down assays. Furthermore, circ_001678 could sponge miR-326 to up-regulate ZEB1. On the other hand, the tumor-promoting effects of circ_001678 could be inhibited by anti-PD-L1/PD-1 treatment. Mechanistically, circ_001678 led to the activation of the PD-1/PD-L1 pathway to promote CD8+ T cell apoptosis, thereby inducing NSCLC cell immune escape via regulation of the miR-326/ZEB1 axis. To conclude, our findings revealed that circ_001678 sponges miR-326 to up-regulate ZEB1 expression and induce the PD-1/PD-L1 pathway-dependent immune escape, thereby promoting the malignant progression of NSCLC.

Comparative Efficacy and Safety of Anti-PD-1/PD-L1 for the Treatment of Non-Small Cell Lung Cancer: A Network Meta-Analysis of 13 Randomized Controlled Studies

Objective

The present network meta-analysis (NMA) was conducted to summarize the direct and indirect evidence of common programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) inhibitors including avelumab, atezolizumab, cemiplimab, nivolumab, and pembrolizumab for the treatment of non-small cell lung cancer (NSCLC) patients and further to determine the optimal therapeutic regimen.

Methods

We performed a systematic literature search to identify all potentially eligible studies in PubMed, Embase, and the Cochrane Library until August 7, 2021. The primary outcome was overall survival (OS), and the second outcome was treatment-related adverse events (TRAEs). We used random-effects model to conduct direct and network meta-analyses, which were performed by using RevMan 5.3 and R version 3.6.1, respectively.

Results

Direct meta-analysis suggested that atezolizumab, cemiplimab, nivolumab, or pembrolizumab significantly improved OS compared with chemotherapy (CT), and NMA further established that atezolizumab [hazard ratio (HR), 0.77; 95% CrI, 0.62-0.96], nivolumab (HR, 0.75; 95% CrI, 0.62-0.93), or pembrolizumab (HR, 0.71; 95% Credible interval (Crl), 0.57-0.89) significantly and cemiplimab (HR, 0.68; 95% CrI, 0.46-1.02) numerically improved OS compared with CT. Meanwhile, NMA also indicated that cemiplimab was numerically superior to other PD-1/PD-L1 agents. Moreover, avelumab, atezolizumab, cemiplimab, nivolumab, and pembrolizumab were found to have fewer TRAEs compared with CT in direct meta-analysis, which were supported by the results from the NMA. Meanwhile, surface under the cumulative ranking curve (SUCRA) and ranking probability suggested that cemiplimab provided the most favorable balance between efficacy and safety, with the first ranking for the OS.

Conclusions

Based on available evidence, cemiplimab may have the most favorable risk-benefit ratio for NSCLC patients compared with other common therapeutic management. However, future research with a large-scale, high-quality, and mature follow-up is needed to further determine which agents should be preferentially selected for NSCLC patients due to the limitations of our NMA and variations of eligible studies in treatment line and PD-L1 status.

Adverse Events Associated with Immune Checkpoint Inhibitors: Overview of Systematic Reviews

BACKGROUND

Recognition and management of adverse events (AEs) associated with immune checkpoint inhibitor (ICI) use by cancer patients requires expertise from multiple disciplines. Greater awareness of potential AEs may result in earlier recognition, appropriate management, and better patient outcomes.

OBJECTIVE

The primary objective of this overview of systematic reviews was to synthesize and consolidate systematic review evidence describing the incidence proportion and severity of AEs associated with various ICI therapies across different cancers.

METHODS

A systematic literature search of four databases was conducted to identify systematic reviews that describe the incidence proportion and severity of AEs related to ICI therapy in cancer patients. A systematic review was eligible if it included adults with cancer; on ICI alone or in combination with another ICI, chemotherapy, or targeted therapy; severity (graded according to the Common Terminology Criteria for Adverse Events) and incidence proportion of AEs and whether it reported its eligibility criteria. AEs of interest were identified through an iterative ranking exercise by key stakeholders and knowledge users. Extraction of PICOTTS elements and quality indicators (AMSTAR-2) were used to manage overlap of primary studies across systematic reviews at the outcome level. Cancer subtypes were mapped to drug class and AE severity.

RESULTS

Overall, 129 systematic reviews met the inclusion criteria for data mapping. Systematic reviews reported incidence proportions for more than 76 AEs, of which 34 were identified as AEs of interest. After overlap assessment, 65 systematic reviews were chosen for data extraction. The three AEs with the highest median incidence were fatigue (18.3%, interquartile range [IQR] 15.0-28.0%), diarrhea (15.3%, IQR 9.7-29.2%) and rash (14.4%, IQR 10.3-19.2%). The three AEs (high-grade) with the highest median incidence were diarrhea (1.5%, IQR 1.2-6.0%), colitis (1.3%, IQR 0.6-6.1%) and neutropenia (1.2%, IQR 0.4-3.3%). Incidence proportions of high-grade AEs were often considerably lower than all-grade AEs and combination therapy (ICI combinations or combinations of ICI with chemotherapy or targeted therapy) was responsible for some of the highest incidence proportions regardless of AE. Rare AEs and certain cancer subtypes were not well reported.

CONCLUSIONS

Early recognition of AEs associated with ICIs requires expertise from diverse specialists, not just oncologists. Greater awareness of potential AEs may result in earlier recognition, appropriate management, and better patient outcomes.

PROSPERO REGISTRATION

CRD42021231593.

Clinical and Prognostic Significance of Tumor-Infiltrating CD8+ T Cells and PD-L1 Expression in Primary Gastrointestinal Stromal Tumors

Purpose

Immunotherapy for gastrointestinal stromal tumors (GISTs) remains a clinical challenge. The present study aimed to explore the clinical and prognostic significance of immune cell infiltration and PD-L1 expression in GISTs.

Methods

A total of 507 clinical tissue specimens of primary GISTs were collected for immunohistochemical analysis of immune cell infiltration and PD-L1 expression. Influencing factors of survival were evaluated by Kaplan–Meier analysis. Univariate and multivariate analyses were performed using the Cox regression model.

Results

There were significant differences in sex, tumor location, size, mitotic index, NIH risk grade, and cell morphology between different gene mutation types of GISTs. Immune cell infiltration in GISTs mainly involved macrophages and T cells. PD-1 was expressed in 48.5% of the tissue specimens, and PD-L1 expression was detected in 46.0% of the samples. PD-L1 expression was negatively correlated with the tumor size and mitotic index but positively correlated with the number of CD8+ T cells. There were significant differences in the number of CD8+ T cells between different gene mutation types. Wild type-mutant GISTs were enriched with CD8+ T cells as compared with KIT- and PDGFRA-mutant GISTs. The number of CD8+ T cells was higher in non-gastric GISTs. PD-L1 and CD8+ T cells were independent predictors for better relapse-free survival of GISTs.

Conclusions

PD-L1 expression is a predictive biomarker for better prognosis of GISTs. Non-gastric GIST patients with wild-type mutations may be the beneficiaries of PD-1/PD-L1 inhibitors.

PD-1 inhibitors versus chemotherapy as second-line treatment for advanced esophageal squamous cell carcinoma: a meta-analysis

BACKGROUND

Aim to establish the inhibitors of programmed cell death protein 1 (PD-1) as second-line therapy for advanced esophageal squamous cell carcinoma (ESCC).

METHODS

Published clinical trials in the PubMed, Medline, Embase databases on PD-1 inhibitors for the treatment of ESCC were searched, along with an additional search on abstracts from the American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) from inception to September 2021. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (TRAEs) were synthesized using STATA.

RESULTS

A total of 1970 patients (PD-1 inhibitors: 987; chemotherapy: 983) were enrolled in five randomized controlled trials. Compared with conventional chemotherapy, second-line PD-1 inhibitors significantly improved the OS (hazard ratio [HR] = 0.73, 95% confidence interval [CI]: 0.66-0.81; P < 0.001) and ORR (relative risk [RR] = 1.89, 95% CI: 1.16-3.05; P = 0.01) of advanced ESCC patients, especially significantly prolonged the OS in the patients with positive programmed death-ligand 1 (PD-L1) status (HR = 0.64, 95% CI: 0.53-0.77; P < 0.001); but did not better PFS (HR = 0.88, 95% CI: 0.68-1.14; P = 0.330) and DCR (RR = 0.89, 95% CI: 0.59-1.37; P = 0.603). Moreover, PD-1 inhibitors were associated with statistically lower incidences of grade 3-5 TRAEs.

CONCLUSION

Second line PD-1 inhibitors significantly improved the OS and ORR of patients with advanced ESCC, especially the OS of those with positive PD-L1 expression, and did not result in significant improvement in PFS and DCR. Compared to chemotherapy, second-line PD-1 inhibitors had superior safety profiles for the treatment of advanced ESCC.

Immune Cell Infiltration and the Expression of PD-1 and PD-L1 in Primary PDGFRA-Mutant Gastrointestinal Stromal Tumors

PURPOSE

To characterize the immune cell profile and expression of PD-1, PD-L1, and IDO in PDGFRA-mutant gastrointestinal stromal tumors (GISTs).

METHODS

The clinicopathological data of PDGFRA-mutant GIST patients who received surgical resection in Zhongshan Hospital between January 2013 and August 2019 were reviewed retrospectively. The specimens of tissue chips were detected for immune cell infiltration and the expression of PD-1, PD-L1, and IDO by immunohistochemical staining.

RESULTS

CD3⁺, CD8⁺, and CD68⁺ cells were the main infiltrating immune cells in the 42 patients included in this study. In addition, CD4⁺, CD56⁺, Foxp3⁺, and CD20⁺ cells were also observed. A higher CD8⁺ T cell count was associated with smaller tumor size and PDGFRA D842V mutation (P = 0.047, P = 0.005). A higher CD3⁺ and CD68⁺ cell count was associated with a higher mitotic index (P = 0.022, P = 0.006). CD4⁺ and CD20⁺ cell count was associated with tumor morphology (P = 0.002, P = 0.045). PD-1 expression was present in 37 (88%) samples. Eighteen samples were positive for PD-L1 expression, and it was higher in small vs. large tumors (P = 0.012) and epithelioid and mixed cell type vs. spindle cell type GISTs (P = 0.046). IDO expression was positive in all 42 patients. The number of CD4⁺ cells was significantly greater in the specimens with high IDO expression (P = 0.012).

CONCLUSION

There were abundant infiltrating immune cells in PDGFRA-mutant GISTs. PD-L1 expression was negatively associated with tumor size. The immunotherapy targeting PD-1/PD-L1 checkpoint and IDO may be valuable.