First-Line Nivolumab Plus Ipilimumab in Advanced Non-Small-Cell Lung Cancer (CheckMate 568): Outcomes by Programmed Death Ligand 1 and Tumor Mutational Burden as Biomarkers

Systematic review and meta-analysis of PD-L1 expression discordance between primary tumor and lung cancer brain metastasis

Background

Novel immunotherapeutic strategies targeting the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) axis are often administered when metastatic tumors show PD-L1 positivity, even in the setting of lung cancer brain metastasis (LCBM). However, biological differences exist between primary tumors and metastatic sites. The objective of this study was to analyze rates of PD-L1 receptor discordance between primary tumors and LCBM.

Methods

A systematic review of studies of biopsied or resected LCBM evaluating PD-L1 discordance published in the Medline database was performed using PRISMA guidelines. Weighted random effects models were used to calculate pooled estimates.

Results

Six full-text articles (n = 230 patients) with a median of 32 patients in each study (range: 24–73) reported PD-L1 receptor expression analyses of both primary lung tumors and brain metastases and met inclusion criteria. The pooled estimate for tumor cell (TC) PD-L1 receptor discordance between primary tumors and LCBM was 19% (95% confidence interval [CI]: 10–27%). For PD-L1 receptor expression in tumor-infiltrating lymphocytes (TIL), the weighted pooled estimate for discordance was 21% (95% CI: 8–44%). For primary versus LCBM, the positive rates by expression levels of <1%, 1–50%, and >50% were 52% (95% CI: 30–73%) versus 56% (95% CI: 34–76%), 30% (95% CI: 22–40%) versus 20% (95% CI: 10–35%), and 15% (95% CI: 6–36%) versus 22% (95% CI: 15–31%) (P = .425), respectively.

Conclusions

PD-L1 discordance occurs in ~20% of LCBM, with the greatest discordance in the 1–50% expression category. Although controversial, confirming discordance might be important for selection of immune checkpoint inhibitor therapy and in the analysis of patterns of failure after treatment.

The Landscape of Immunotherapy in Advanced NSCLC: Driving Beyond PD-1/PD-L1 Inhibitors (CTLA-4, LAG3, IDO, OX40, TIGIT, Vaccines)

PURPOSE OF REVIEW

In this review, we analyzed the current landscape of non-PD-(L)1 targeting immunotherapy.

RECENT FINDINGS

The advent of immunotherapy has completely changed the standard approach toward advanced NSCLC. Inhibitors of the PD-1/PD-L1 axis have quickly taken place as first-line treatment for NSCLC patients without targetable "driver" mutations. However, a non-negligible portion of patients derive modest benefit from immune-checkpoint inhibitors, and valid second-line alternatives are lacking, pushing researchers to analyze other molecules and pathways as potentially viable targets in the struggle against NSCLC. Starting from the better characterized CTLA-4 inhibitors, we then critically collected the actual knowledge on NSCLC vaccines as well as on other emerging molecules, many of them in their early phase of testing, to provide to the reader a comprehensive overview of the state of the art of immunotherapy in NSCLC beyond PD-1/PD-L1 inhibitors.

Tumor mutational burden on cytological samples: A pilot study

BACKGROUND

Immune-checkpoint inhibitors (ICIs) represent an important treatment option for patients who have advanced stage non-small cell lung cancer (NSCLC). Currently, evaluation of the expression level of programmed death-ligand 1 (PD-L1) has proven highly successful as a positive predictive biomarker for ICIs. In addition to PD-L1, other promising predictive biomarkers are emerging, including high tumor mutational burden (TMB-H). However, measuring TMB-H remains challenging for several reasons, among which is the difficulty in obtaining adequate tissue material from NSCLC patients. There are no data in the current literature regarding the possibility of adopting cell blocks (CBs) for TMB evaluation; therefore, our goal was to evaluate the feasibility of analyzing TMB on CBs.

METHODS

For evaluation of differences in run metric parameters, 8 pairs of histological and CB samples from patients with NSCLC were analyzed using the Oncomine Tumor Mutational Load Assay on Ion Torrent S5 GS next-generation sequencing (NGS) platform.

RESULTS

Most CBs (6/8, 75.0%) were successfully analyzed by adopting the broad NGS panel approach. CBs provided results similar to those obtained on histological matched specimens in terms of median total reads (7207048.80 vs 7558817.80), median mapped reads (7075753.83 vs 7513822.00), median read lengths (115.50 vs. 113.00), median percentage of reads on-target (97.49% vs. 98.45%), median average reads per amplicon (454.67 vs 476.14), and median uniformity of amplicon coverage (83.52% vs 84.13%).

CONCLUSION

In this pilot study, we demonstrated the technical feasibility of assessing TMB on CBs.

A Blood-based Assay for Assessment of Tumor Mutational Burden in First-line Metastatic NSCLC Treatment: Results from the MYSTIC Study

PURPOSE

Tumor mutational burden (TMB) has been shown to be predictive of survival benefit in patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors. Measuring TMB in the blood (bTMB) using circulating cell-free tumor DNA (ctDNA) offers practical advantages compared with TMB measurement in tissue (tTMB); however, there is a need for validated assays and identification of optimal cutoffs. We describe the analytic validation of a new bTMB algorithm and its clinical utility using data from the phase III MYSTIC trial.

PATIENTS AND METHODS

The dataset used for the clinical validation was from MYSTIC, which evaluated first-line durvalumab (anti-PD-L1 antibody) ± tremelimumab (anticytotoxic T-lymphocyte-associated antigen-4 antibody) or chemotherapy for metastatic NSCLC. bTMB and tTMB were evaluated using the GuardantOMNI and FoundationOne CDx assays, respectively. A Cox proportional hazards model and minimal P value cross-validation approach were used to identify the optimal bTMB cutoff.

RESULTS

In MYSTIC, somatic mutations could be detected in ctDNA extracted from plasma samples in a majority of patients, allowing subsequent calculation of bTMB. The success rate for obtaining valid TMB scores was higher for bTMB (809/1,001; 81%) than for tTMB (460/735; 63%). Minimal P value cross-validation analysis confirmed the selection of bTMB ≥20 mutations per megabase (mut/Mb) as the optimal cutoff for clinical benefit with durvalumab + tremelimumab.

CONCLUSIONS

Our study demonstrates the feasibility, accuracy, and reproducibility of the GuardantOMNI ctDNA platform for quantifying bTMB from plasma samples. Using the new bTMB algorithm and an optimal bTMB cutoff of ≥20 mut/Mb, high bTMB was predictive of clinical benefit with durvalumab + tremelimumab versus chemotherapy.

Bacterial Outer Membrane Vesicles Presenting Programmed Death 1 for Improved Cancer Immunotherapy via Immune Activation and Checkpoint Inhibition

Natural, extracellular membrane vesicles secreted by Gram-negative bacteria, outer membrane vesicles (OMVs), contain numerous pathogen-associated molecular patterns which can activate systemic immune responses. Previous studies have shown that OMVs induce strong IFN-γ- and T cell-mediated anti-tumor effects in mice. However, IFN-γ is known to upregulate immunosuppressive factors in the tumor microenvironment, especially the immune checkpoint programmed death 1 ligand 1 (PD-L1), which may hamper T cell function and limit immunotherapeutic effectiveness. Here, we report the development of genetically engineered OMVs whose surface has been modified by insertion of the ectodomain of programmed death 1 (PD1). This genetic modification does not affect the ability of OMVs to trigger immune activation. More importantly, the engineered OMV-PD1 can bind to PD-L1 on the tumor cell surface and facilitate its internalization and reduction, thereby protecting T cells from the PD1/PD-L1 immune inhibitory axis. Through the combined effects of immune activation and checkpoint suppression, the engineered OMVs drive the accumulation of effector T cells in the tumor, which, in turn, leads to a greater impairment of tumor growth, compared with not only native OMVs but also the commonly used PD-L1 antibody. In conclusion, this work demonstrates the potential of bioengineered OMVs as effective immunotherapeutic agents that can comprehensively regulate the tumor immune microenvironment to effect markedly increased anti-tumor efficacy.

Beyond Tumor PD-L1: Emerging Genomic Biomarkers for Checkpoint Inhibitor Immunotherapy

Despite the success of immune checkpoint blockade as a strategy for activating an antitumor immune response and promoting cancer regression, only a subset of patients have durable clinical benefit. Efforts are ongoing to identify robust biomarkers that can effectively predict treatment response to immune checkpoint inhibitors (ICIs). Although PD-L1 expression is useful for stratifying patients, it is an imperfect tool. Comprehensive next-generation sequencing platforms that are readily used in clinical practice to identify a tumor's potentially actionable genetic alterations also reveal tumor genomic features, including tumor mutation burden (TMB), that may impact the response to ICIs. High TMB enhances tumor immunogenicity through increased numbers of tumor neoantigens that may promote an immune response. Defective DNA repair, leading to microsatellite instability, is an endogenous mechanism for increased tumor TMB that augments response to anti-PD-1 blockade. Alternatively, DNA damage from exogenous factors is responsible for high TMB seen in melanoma, lung cancer, and urothelial carcinoma, among tumor subtypes with higher response rates to ICIs. In this review, we summarize data supporting the use of TMB as a biomarker as well as its known limitations. We also highlight specific tumor suppressor genes and oncogenes that are under investigation as biomarkers for ICI response and resistance. Efforts are ongoing to delineate which genomic tumor characteristics can eventually be utilized in clinical practice to ascertain the benefit of ICIs for an individual patient.

Single or combined immune checkpoint inhibitors compared to first-line platinum-based chemotherapy with or without bevacizumab for people with advanced non-small cell lung cancer

BACKGROUND

Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis have changed the first-line treatment of people with advanced non-small cell lung cancer (NSCLC). Single-agent pembrolizumab (a PD-1 inhibitor) is currently the standard of care as monotherapy in patients with PD-L1 expression ≥ 50%, either alone or in combination with chemotherapy when PD-L1 expression is less than 50%. Atezolizumab (PD-L1 inhibitor) has also been approved in combination with chemotherapy and bevacizumab (an anti-angiogenic antibody) in first-line NSCLC regardless of PD-L1 expression. The combination of first-line PD-1/PD-L1 inhibitors with anti-CTLA-4 antibodies has also been shown to improve survival compared to platinum-based chemotherapy in advanced NSCLC, particularly in people with high tumour mutational burden (TMB). The association of ipilimumab (an anti CTLA4) and nivolumab (PD-1 inhibitor) has been approved by the US Food and Drug Administration (FDA) in all patients with PD-L1 expression ≥1%. Although these antibodies are currently used in clinical practice, some questions remain unanswered, such as the best-treatment strategy, the role of different biomarkers for treatment selection and the effectiveness of immunotherapy according to specific clinical characteristics.

OBJECTIVES

Primary objective: to determine the effectiveness and safety of first-line immune checkpoint inhibitors (ICIs), as monotherapy or in combination, compared to platinum-based chemotherapy, with or without bevacizumab for people with advanced NSCLC, according to the level of PD-L1 expression.

SECONDARY OBJECTIVE

to maintain the currency of evidence using a living systematic review approach.

SEARCH METHODS

We performed an electronic search of the main databases (Cochrane Lung Cancer Group Trial Register, Cochrane Central Register of Controlled Trials, MEDLINE, Embase) from inception until 21 October 2020 and conferences meetings from 2015 onwards.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) reporting on the efficacy or safety of first-line ICI treatment for adults with advanced NSCLC who had not previously received any anticancer treatment. We included trials comparing single- or double-ICI treatment to standard first-line therapy (platinum-based chemotherapy +/- bevacizumab). All data come from 'international multicentre studies involving adults, age 18 or over, with histologically-confirmed stage IV NSCLC who had not received any previous systemic anti-cancer treatment for advanced disease.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed the search results and a fourth review author resolved any disagreements. Primary outcomes were overall survival (OS) and progression-free survival (PFS); secondary outcomes were overall objective response rate (ORR) by RECIST v 1.1, grade 3 to 5 treatment-related adverse events (AEs) (CTCAE v 5.0) and health-related quality of life (HRQoL). We performed meta-analyses where appropriate using the random-effects model for hazard ratios (HRs) or risk ratios (RRs), with 95% confidence intervals (95% CIs), and used the I² statistic to investigate heterogeneity.

MAIN RESULTS

Main results We identified 15 trials for inclusion, seven completed and eight ongoing trials. We obtained data for 5893 participants from seven trials comparing first-line single- (six trials) or double- (two trials) agent ICI with platinum-based chemotherapy, one trial comparing both first-line single- and double-agent ICsI with platinum-based chemotherapy. All trials were at low risk of selection and detection bias, some were classified at high risk of performance, attrition or other source of bias. The overall certainty of evidence according to GRADE ranged from moderate-to-low because of risk of bias, inconsistency, or imprecision. The majority of the included trials reported their outcomes by PD-L1 expressions, with PD-L1 ≥ 50 being considered the most clinically useful cut-off level for decision makers. Also, iIn order to avoid overlaps between various PDL-1 expressions we prioritised the review outcomes according to PD-L1 ≥ 50. Single-agent ICI In the PD-L1 expression ≥ 50% group single-agent ICI probably improved OS compared to platinum-based chemotherapy (hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.60 to 0.76, 6 RCTs, 2111 participants, moderate-certainty evidence). In this group, single-agent ICI also may improve PFS (HR: 0.68, 95% CI 0.52 to 0.88, 5 RCTs, 1886 participants, low-certainty evidence) and ORR (risk ratio (RR):1.40, 95% CI 1.12 to 1.75, 4 RCTs, 1672 participants, low-certainty evidence). HRQoL data were available for only one study including only people with PD-L1 expression ≥ 50%, which suggested that single-agent ICI may improve HRQoL at 15 weeks compared to platinum-based chemotherapy (RR: 1.51, 95% CI 1.08 to 2.10, 1 RCT, 297 participants, low-certainty evidence). In the included studies, treatment-related AEs were not reported according to PD-L1 expression levels. Grade 3-4 AEs may be less frequent with single-agent ICI compared to platinum-based chemotherapy (RR: 0.41, 95% CI 0.33 to 0.50, I² = 62%, 5 RCTs, 3346 participants, low-certainty evidence). More information about efficacy of single-agent ICI compared to platinum-based chemotherapy according to the level of PD-L1 expression and to TMB status or specific clinical characteristics is available in the full text. Double-agent ICI Double-ICI treatment probably prolonged OS compared to platinum-based chemotherapy in people with PD-L1 expression ≥50% (HR: 0.72, 95% CI 0.59 to 0.89 2 RCTs, 612 participants, moderate-certainty evidence). Trials did not report data on HRQoL, PFS and ORR according to PD-L1 groups. Treatment related AEs were not reported according to PD-L1 expression levels. The frequency of grade 3-4 AEs may not differ between double-ICI treatment and platinum-based chemotherapy (RR: 0.78, 95% CI 0.55 to 1.09, I² = 81%, 2 RCTs, 1869 participants, low-certainty evidence). More information about efficacy of double-agent ICI according to the level of PD-L1 expression and to TMB status is available in the full text.

AUTHORS' CONCLUSIONS

Authors' conclusions The evidence in this review suggests that single-agent ICI in people with NSCLC and PD-L1 ≥50% probably leads to a higher overall survival rate and may lead to a higher progression-free survival and overall response rate when compared to platinum-based chemotherapy and may also lead to a lower rate of adverse events and higher HRQoL. Combined ICI in people with NSCLC and PD-L1 ≥50% also probably leads to a higher overall survival rate when compared to platinum-based chemotherapy, but its effect on progression-free survival, overall response rate and HRQoL is unknown due to a lack of data. The rate of adverse events may not differ between groups.

Long non-coding RNA C5orf64 is a potential indicator for tumor microenvironment and mutation pattern remodeling in lung adenocarcinoma

Understanding the synergistic and antagonistic effects of tumor microenvironment (TME) and tumor mutation pattern on lung adenocarcinoma (LUAD) is urgently needed. Herein, we applied ESTIMATE and CIBERSORT methods to calculate the ratio of immune and stromal components and TIICs proportion of LUAD samples from TCGA database. Immune-related genes were analyzed by Lasso regression analysis and used for ceRNA network construction. A 14-lncRNA immune-related signature was developed, among which C5orf64 was found to be positively correlated with abundances of M2 macrophages, monocytes, eosinophils and neutrophils, but negatively correlated with Tregs and plasma cells. PD-1, PD-L1 and CTLA-4 were demonstrated to be high expressed in high-level C5orf64 groups. However, C5orf64 had a negative correlation with TP53 mutation frequency. A novel model was built based on age, tumor stage and immune-related lncRNA signature. To conclude, lncRNA C5orf64 had potential to be an indicator for TME modulation and tumor mutation pattern remodeling in LUAD.

Tumor Mutational Burden as a Predictive Biomarker in Solid Tumors

Tumor mutational burden (TMB), defined as the number of somatic mutations per megabase of interrogated genomic sequence, varies across malignancies. Panel sequencing-based estimates of TMB have largely replaced whole-exome sequencing-derived TMB in the clinic. Retrospective evidence suggests that TMB can predict the efficacy of immune checkpoint inhibitors, and data from KEYNOTE-158 led to the recent FDA approval of pembrolizumab for the TMB-high tumor subgroup. Unmet needs include prospective validation of TMB cutoffs in relationship to tumor type and patient outcomes. Furthermore, standardization and harmonization of TMB measurement across test platforms are important to the successful implementation of TMB in clinical practice. SIGNIFICANCE: Evaluation of TMB as a predictive biomarker creates the need to harmonize panel-based TMB estimation and standardize its reporting. TMB can improve the predictive accuracy for immunotherapy outcomes, and has the potential to expand the candidate pool of patients for treatment with immune checkpoint inhibitors.

SITC cancer immunotherapy resource document: a compass in the land of biomarker discovery

Since the publication of the Society for Immunotherapy of Cancer's (SITC) original cancer immunotherapy biomarkers resource document, there have been remarkable breakthroughs in cancer immunotherapy, in particular the development and approval of immune checkpoint inhibitors, engineered cellular therapies, and tumor vaccines to unleash antitumor immune activity. The most notable feature of these breakthroughs is the achievement of durable clinical responses in some patients, enabling long-term survival. These durable responses have been noted in tumor types that were not previously considered immunotherapy-sensitive, suggesting that all patients with cancer may have the potential to benefit from immunotherapy. However, a persistent challenge in the field is the fact that only a minority of patients respond to immunotherapy, especially those therapies that rely on endogenous immune activation such as checkpoint inhibitors and vaccination due to the complex and heterogeneous immune escape mechanisms which can develop in each patient. Therefore, the development of robust biomarkers for each immunotherapy strategy, enabling rational patient selection and the design of precise combination therapies, is key for the continued success and improvement of immunotherapy. In this document, we summarize and update established biomarkers, guidelines, and regulatory considerations for clinical immune biomarker development, discuss well-known and novel technologies for biomarker discovery and validation, and provide tools and resources that can be used by the biomarker research community to facilitate the continued development of immuno-oncology and aid in the goal of durable responses in all patients.

Imperfect Predictors for Lung Cancer Immunotherapy-A Field for Further Research

The armamentarium for lung cancer immunotherapy has been strengthened using two groups of monoclonal antibodies: 1) anti-PD-1 antibodies, including pembrolizumab and nivolumab, which block the programmed death 1 receptor on the lymphocyte surface, resulting in increasing activity of these cells, and 2) anti-PD-L1 antibodies, including atezolizumab, durvalumab, and avelumab, which block the ligand for the PD-1 molecule on tumor cells and on tumor-infiltrating immune cells. The effectiveness of both groups of antibodies has been proven in many clinical trials, which translates into positive immunotherapeutic registrations for cancer patients. Regarding the predictive factor, PD-L1 expression on cancer cells is the only biomarker validated in prospective clinical trials used for qualification to immunotherapy in advanced non-small cell lung cancer (NSCLC) patients. However, it is not an ideal one. Unfortunately, no clinical benefits could be noted in patients with high PD-L1 expression on tumor cells against the effectiveness of immunotherapy that may be observed in patients without PD-L1 expression. Furthermore, the mechanism of antitumor immune response is extremely complex, multistage, and depends on many factors. Cancer cells could be recognized by the immune system, provided tumor-specific antigen presentation, and these arise as a result of somatic mutations in tumor cells. Based on novel immunotherapy registration, high tumor mutation burden (TMB) has become an important predictive factor. The intensity of lymphocyte infiltration in tumor tissue may be another predictive factor. The effectiveness of anti-PD-L1 immunotherapy is observed in patients with high expression of genes associated with the effector function of T lymphocytes (i.e., their ability to produce IFN-gamma). This does not end the list of potential factors that become useful in qualification of cancer patients for immunotherapy. There remains a need to search for new and perfect predictive factors for immunotherapy.

What is the Burden of Proof for Tumor Mutational Burden in gliomas?

The treatment of patients with a variety of solid tumors has benefitted from immune checkpoint inhibition targeting the anti-programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) axis. The US Food and Drug Administration (FDA) granted accelerated approval of PD-1 inhibitor pembrolizumab for the treatment of adult and pediatric patients with TMB-high (TMB-H), solid tumors that have progressed following prior treatment and who have no other treatment options, including the extension to tumors of the Central Nervous System (CNS). In general, pan-cancer approvals are viewed positively to empower patients and clinicians. There are subsets (eg, BRAF, NTRK) for which this pathway for approval is appropriate. However, the pan-cancer FDA approval of pembrolizumab raises several concerns regarding the generalizability of the evidence to other tumor types, including managing patients with gliomas and other CNS tumors. The cut off for TMB-H is not well defined. There are intrinsic immunological differences between gliomas and other cancers types, including the immunosuppressive glioma microenvironment, the tumor's effects on systemic immune function, and the transformation of the T cell populations to an exhausted phenotype in glioma. Here we address the caveats with pan-cancer approvals concerning gliomas, complexities of the unique CNS immune environment, and discuss potential predictive biomarkers, including TMB, and explain why the recent approval should be applied with caution in CNS tumors.

Radiotherapy and Immunotherapy Combinations for Lung Cancer

PURPOSE OF REVIEW

Positive results from recent immunotherapy trials of non-small cell lung cancer (NSCLC) have coincided with a greater appreciation for the impact of radiation therapy (RT) on tumor immunity. Here, we summarize key clinical findings and ongoing efforts to combine immunotherapy and RT for the treatment of NSCLC.

RECENT FINDINGS

The role of immunotherapy for NSCLC has expanded significantly following the pivotal approvals of nivolumab and pembrolizumab for metastatic NSCLC, maintenance durvalumab in unresectable stage III NSCLC, and atezolizumab for metastatic NSCLC. Several small early-phase trials have demonstrated the ability of RT to elicit clinically significant tumor immunity. These positive findings support current trial efforts combining RT with immunotherapy for NSCLC. Recently initiated trials of RT and immunotherapy hold significant promise in expanding the therapeutic options for NSCLC. Optimization of therapy will require careful patient selection to yield meaningful improvements in clinical outcomes.

Association of clinico-genomic characteristics with tumor mutational burden in small cell lung cancer patients

Aim: We evaluated the relationship between clinical and genomic characteristics and tumor mutational burden (TMB) in small cell lung cancer. Materials & methods: In a retrospective analysis of small cell lung cancer patients aged ≥18, we assessed treatment patterns and survival in relation to TMB; the association of clinical and genomic characteristics with TMB was determined by multivariate regression. High TMB (TMB-H) was defined as ≥10 mutations/megabase. Results: Among 186 patients, treatment patterns and overall survival were similar for TMB-H and non-TMB-H patients. TMB was determined for 179 patients, 41.9% of whom were TMB-H. Short variants of LRP1B, FAT3, MLL3, MED12 and NOTCH3 were significantly associated with TMB-H (p ≤ 0.01). Conclusion: Neither treatment patterns nor survival differed by TMB status.

Characterization of the genomic landscape and actionable mutations in Chinese breast cancers by clinical sequencing

The remarkable advances in next-generation sequencing technology have enabled the wide usage of sequencing as a clinical tool. To promote the advance of precision oncology for breast cancer in China, here we report a large-scale prospective clinical sequencing program using the Fudan-BC panel, and comprehensively analyze the clinical and genomic characteristics of Chinese breast cancer. The mutational landscape of 1,134 breast cancers reveals that the most significant differences between Chinese and Western patients occurred in the hormone receptor positive, human epidermal growth factor receptor 2 negative breast cancer subtype. Mutations in p53 and Hippo signaling pathways are more prevalent, and 2 mutually exclusive and 9 co-occurring patterns exist among 9 oncogenic pathways in our cohort. Further preclinical investigation partially suggests that NF2 loss-of-function mutations can be sensitive to a Hippo-targeted strategy. We establish a public database (Fudan Portal) and a precision medicine knowledge base for data exchange and interpretation. Collectively, our study presents a leading approach to Chinese precision oncology treatment and reveals potentially actionable mutations in breast cancer.

Chinese breast cancer patients have not been well represented in clinical sequencing studies. Here the authors analyse the mutational landscape of 1,134 Chinese breast cancer patients, finding actionable targets and a higher prevalence of p53 and Hippo pathway mutations compared to Western cohorts.

DNA-protein biomarkers for immunotherapy in the era of precision oncology

The use of biomarkers to guide patient and therapy selection has gained much attention to increase the scope and complexity of targeted therapy options and immunotherapy. Clinical trials provide a basis for discovery of biomarkers, which can then aid in development of new drugs. To that end, samples from cancer patients, including DNA, RNA, protein, and the metabolome isolated from cancer tissues and blood or urine, are analyzed in various ways to identify relevant biomarkers. In conjunction with nucleotide-based, high-throughput, next-generation sequencing techniques, therapy-guided biomarker assays relying on protein-based immunohistochemistry play a pivotal role in cancer care. In this review, we discuss the current knowledge regarding DNA and protein biomarkers for cancer immunotherapy.

The PD-1/PD-L1-Checkpoint Restrains T cell Immunity in Tumor-Draining Lymph Nodes

PD-1/PD-L1-checkpoint blockade therapy is generally thought to relieve tumor cell-mediated suppression in the tumor microenvironment but PD-L1 is also expressed on non-tumor macrophages and conventional dendritic cells (cDCs). Here we show in mouse tumor models that tumor-draining lymph nodes (TDLNs) are enriched for tumor-specific PD-1⁺ T cells which closely associate with PD-L1⁺ cDCs. TDLN-targeted PD-L1-blockade induces enhanced anti-tumor T cell immunity by seeding the tumor site with progenitor-exhausted T cells, resulting in improved tumor control. Moreover, we show that abundant PD-1/PD-L1-interactions in TDLNs of nonmetastatic melanoma patients, but not those in corresponding tumors, associate with early distant disease recurrence. These findings point at a critical role for PD-L1 expression in TDLNs in governing systemic anti-tumor immunity, identifying high-risk patient groups amendable to adjuvant PD-1/PD-L1-blockade therapy.

Association of the Pretreatment Lung Immune Prognostic Index with Survival Outcomes in Advanced Hepatocellular Carcinoma Patients Treated with PD-1 Inhibitors

Purpose

At present, there are no validated biomarkers that can predict whether patients with advanced hepatocellular carcinoma (aHCC) are likely to benefit from anti-PD-1 therapy. We aimed to determine whether lung immune prognostic index (LIPI) is associated with outcomes in patients with aHCC treated with PD-1 inhibitors.

Patients and Methods

Patients undergoing initial treatment with PD-1 inhibitors for aHCC at a single center from January 1, 2015 to August 31, 2019 were included. The patients were stratified according to pretreatment LIPI based on a derived neutrophils/(leukocytes minus neutrophils) ratio (dNLR) ≥ 3 and a lactate dehydrogenase (LDH) level ≥ the upper limit of normal (ULN). Kaplan–Meier analysis and the Log rank test were used to calculate and compare survival between good LIPI and intermediate/poor LIPI scores. The prognostic values of LIPI for survival and disease control rate were evaluated using Cox proportional hazard and logistic regression models, respectively.

Results

Of the 108 study patients, 53 (49%) had a good LIPI (dNLR < 3 and LDH normal) and 55 (51%) had intermediate/poor LIPI (dNLR ≥ 3 or/and LDH ≥ ULN). With a median follow-up of 12.4 months, intermediate/poor LIPI was independently associated with shorter overall survival (OS) (hazard ratio [HR] 4.00; 95% CI, 2.00–8.03) and progression-free survival (PFS) (HR 2.65; 95% CI, 1.61–4.37). The median OS for good and intermediate/poor LIPI was not reached and was 13.7 (95% CI, 8.2–19.1) months, respectively, and the median PFS was 10.9 (95% CI, 8.9–12.9) and 4.0 (95% CI, 2.2–5.8) months (both P < 0.001), respectively.

Conclusion

Pretreatment LIPI combined with a dNLR ≥ 3 and/or LDH ≥ ULN is associated with poor outcomes in patients with aHCC treated with PD-1 inhibitors. Further validation in large, prospective studies are warranted.

Hot or Not: Tumor Mutational Burden (TMB) as a Biomarker of Immunotherapy Response in Genitourinary Cancers

Pembrolizumab was recently approved for treatment of cancers with high tumor mutational burden (TMB). We conduct a focused literature review of TMB as a predictive biomarker. TMB quantifies the sum of nonsynonymous coding mutations (typically single nucleotide substitutions and short insertion-deletions) per megabase of sequenced DNA. As a proxy for expression of immunogenic neoantigens, TMB may be an effective predictive biomarker for response to immune checkpoint inhibitors. However, like other biomarkers in this setting, TMB has many limitations; the effect of this FDA approval in the current management of genitourinary cancers is likely limited to select situations.

Somatic HLA Class I Loss Is a Widespread Mechanism of Immune Evasion Which Refines the Use of Tumor Mutational Burden as a Biomarker of Checkpoint Inhibitor Response

Neoantigen presentation arises as a result of tumor-specific mutations and is a critical component of immune surveillance that can be abrogated by somatic LOH of the human leukocyte antigen class I (HLA-I) locus. To understand the role of HLA-I LOH in oncogenesis and treatment, we utilized a pan-cancer genomic dataset of 83,644 patient samples, a small subset of which had treatment outcomes with immune checkpoint inhibitors (ICI). HLA-I LOH was common (17%) and unexpectedly had a nonlinear relationship with tumor mutational burden (TMB). HLA-I LOH was frequent at intermediate TMB, yet prevalence decreased above 30 mutations/megabase, suggesting highly mutated tumors require alternate immune evasion mechanisms. In ICI-treated patients with nonsquamous non-small cell lung cancer, HLA-I LOH was a significant negative predictor of overall survival. Survival prediction improved when combined with TMB, suggesting TMB with HLA-I LOH may better identify patients likely to benefit from ICIs. SIGNIFICANCE: This work shows the pan-cancer landscape of HLA-I LOH, revealing an unexpected "Goldilocks" relationship between HLA-I LOH and TMB, and demonstrates HLA-I LOH as a significant negative predictor of outcomes after ICI treatment. These data informed a combined predictor of outcomes after ICI and have implications for tumor vaccine development.This article is highlighted in the In This Issue feature, p. 211.

Angiotensin-converting enzyme (ACE) inhibitor prescription affects non-small-cell lung cancer (NSCLC) patients response to PD-1/PD-L1 immune checkpoint blockers

Angiotensin-converting enzyme (ACE) inhibitors are frequently used to treat hypertension and congestive heart failure. Preclinical data show that ACE plays a role on both innate and adaptive immune responses. Since interactions between ACE inhibitors and immune checkpoint inhibitors (ICIs) have not been reported, the aim of this study is to investigate the influence of ACE inhibitors on non-small cell lung cancer (NSCLC) patients treated with programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) inhibitors. We conducted a retrospective cohort analysis of NSCLC patients treated with PD-1/PD-L1 inhibitors. Clinical and co-medication data as well as tumor biopsies were collected. Groups were defined according to patients' co-medications at the time of ICI initiation. Among the 178 patients included, 22 (13.1%) received ACE inhibitors. While baseline characteristics were similar in both groups, ACE inhibitors group had a shorter median PFS (Progression-Free Survival) compared to the control group: 1.97 vs. 2.56 months, p = .01 (HR = 1.8 CI95% 1.1-2.8). Using CIBERSORT, RNA sequencing suggested that tumors from the ACE inhibitors group had less M1 macrophages, activated mast cells, NK cells and memory activated T cells, thus suggesting an immunosuppressed state. In vitro, the ACE inhibitor, captopril, induced M2 marker at the cell surface of monocytes engaged into M1 differentiation. Thus, ACE inhibitors prescription concomitant to PD-1/PD-L1 inhibitors treatment seems to be associated with impaired outcome and with a tumor immunosuppressed state in patients with advanced NSCLC. These results should be validated in larger prospective cohorts.

Implementing ctDNA Analysis in the Clinic: Challenges and Opportunities in Non-Small Cell Lung Cancer

Tumor genomic profiling has a dramatic impact on the selection of targeted treatment and for the identification of resistance mechanisms at the time of progression. Solid tissue biopsies are sometimes challenging, and liquid biopsies are used as a non-invasive alternative when tissue is limiting. The clinical relevance of tumor genotyping through analysis of ctDNA is now widely recognized at all steps of the clinical evaluation process in metastatic non-small cell lung cancer (NSCLC) patients. ctDNA analysis through liquid biopsy has recently gained increasing attention as well in the management of early and locally advanced, not oncogene-addicted, NSCLC. Its potential applications in early disease detection and the response evaluation to radical treatments are promising. The aim of this review is to summarize the landscape of liquid biopsies in clinical practice and also to provide an overview of the potential perspectives of development focusing on early detection and screening, the assessment of minimal residual disease, and its potential role in predicting response to immunotherapy. In addition to available studies demonstrating the clinical relevance of liquid biopsies, there is a need for standardization and well-designed clinical trials to demonstrate its clinical utility.

Immune checkpoint blockade and biomarkers of clinical response in non-small cell lung cancer

Immunotherapy with PD‐1 and PD‐L1 inhibitors has revolutionized the treatment for patients with NSCLC the last years with increased overall survival and in particular increased number of long‐time survivors in patients with metastatic disease. It is now a treatment of choice for patients with distant metastases (stage IV) and in conjunction with chemoradiotherapy for patients with limited spread confined to the chest (stage III). PD‐1 inhibition has been proven to be superior to standard chemotherapy, both as a single treatment and when combined with either chemotherapy or CTLA‐4 inhibition. Despite the success of immunotherapy, the majority of patients do not respond or relapse within a short time frame. Biomarkers that would help to properly select patients with a high likelihood of clinical response to PD‐1 and PD‐L1 inhibitors are scarce and far from optimal, and only one (PD‐L1 expression) has reached clinical practice. Thus for immunotherapy to be effective, the discovery and validation of additional biomarkers is critical for patient selection and prediction of clinical response. In this mini‐review, we give an overview of current clinical management of NSCLC including treatment landscape with regard to immunotherapy, as well as discuss the current genetic and immune cell biomarker studies and their potential for introduction into clinical practice.

The incidence risk of programmed cell death-1/programmed cell death ligand 1 inhibitor-related alopecia for cancer patients: A systematic review and meta-analysis

PURPOSE

To evaluate the incidence risk of programmed cell death-1/programmed cell death ligand 1 (PD-1/PD-L1) inhibitor-related alopecia for cancer patients, the meta-analysis was put into practice.

METHOD

The meta-analysis was designed and put into practice according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines.

RESULTS

After rigorous screening and verification, 22 clinical trials involving PD-1/PD-L1 inhibitors were collected for the final comprehensive analysis. The incidence risk of alopecia for all-grade in the PD-1/PD-L1 group was significantly lower than that in the control chemotherapy group (odds ratio [OR] = 0.01, 95% confidence interval [CI]: [0.01, 0.04], I = 86%, Z = 8.73 [P < .00001]). Similar to the above, the incidence risk of alopecia for grade 3-5 related to PD-1/PD-L1 was obvious lower than the control group (OR = 0.17, 95% CI:[0.05, 0.55], I = 0%, Z = 2.97 [P = .003]). When 7 clinical trials (PD-1/PD-L1 + Chemotherapy vs Chemotherapy) were taken to evaluate the risk of alopecia for all-grade and grade 3-5, no statistically significant results were found.

CONCLUSION

The incidence risk of alopecia caused by PD-1/PD-L1 is significantly lower than chemotherapy, and there is no statistical significant evidence that PD-1/PD-L1 combined with chemotherapy would increase the incidence risk of alopecia.

Emerging Blood-Based Biomarkers for Predicting Response to Checkpoint Immunotherapy in Non-Small-Cell Lung Cancer

Immune checkpoint inhibitors (ICIs) have brought impressive clinical benefits in a variety of malignancies over the past years, which dramatically revolutionized the cancer treatment paradigm. Monotherapy or in combination with chemotherapy of ICIs targeting programmed death 1/programmed death ligand 1 (PD-L1) has emerged as an alternative treatment for patients with advanced non-small-cell lung cancer (NSCLC). However, constrained by primary or acquired resistance, most patients obtain limited benefits from ICIs and occasionally suffer from severe immune-related adverse events. Moreover, owing to the complexity of the tumor microenvironment and the technical limitations, clinical application of PD-L1 and tumor mutation burden as biomarkers shows many deficiencies. Thus, additional predictive biomarkers are required to further advance the precision of proper patient selection, avoiding the exposure of potential non-responders to unnecessary immunotoxicity. Nowadays, an increasing number of investigations are focusing on peripheral blood as a noninvasive alternative to tissue biopsy in predicting and monitoring treatment outcomes. Herein, we summarize the emerging blood-based biomarkers that could predict the clinical response to checkpoint immunotherapy, specifically in patients with NSCLC.

From Tumor Mutational Burden to Blood T Cell Receptor: Looking for the Best Predictive Biomarker in Lung Cancer Treated with Immunotherapy

Despite therapeutic advances, lung cancer (LC) is one of the leading causes of cancer morbidity and mortality worldwide. Recently, the treatment of advanced LC has experienced important changes in survival benefit due to immune checkpoint inhibitors (ICIs). However, overall response rates (ORR) remain low in unselected patients and a large proportion of patients undergo disease progression in the first weeks of treatment. Therefore, there is a need of biomarkers to identify patients who will benefit from ICIs. The programmed cell death ligand 1 (PD-L1) expression has been the first biomarker developed. However, its use as a robust predictive biomarker has been limited due to the variability of techniques used, with different antibodies and thresholds. In this context, tumor mutational burden (TMB) has emerged as an additional powerful biomarker based on the observation of successful response to ICIs in solid tumors with high TMB. TMB can be defined as the total number of nonsynonymous mutations per DNA megabases being a mechanism generating neoantigens conditioning the tumor immunogenicity and response to ICIs. However, the latest data provide conflicting results regarding its role as a biomarker. Moreover, considering the results of the recent data, the use of peripheral blood T cell receptor (TCR) repertoire could be a new predictive biomarker. This review summarises recent findings describing the clinical utility of TMB and TCRβ (TCRB) and concludes that immune, neontigen, and checkpoint targeted variables are required in combination for accurately identifying patients who most likely will benefit of ICIs.

Principles of Immunotherapy in Non-Small Cell Lung Cancer

Immunotherapy has transformed the treatment of many tumors. Robust data demonstrating improved overall survival and progression-free survival in patients treated with monoclonal antibodies have established immune checkpoint inhibitors as standard of care in stages III and IV non-small cell lung cancer. Nivolumab is effective in previously treated patients with metastatic non-small cell lung cancer. Pembrolizumab and atezolizumab are approved as monotherapy and in combination with other therapies. Ongoing trials investigate the potential role of immunotherapy in earlier disease settings. Identifying predictive biomarkers of response will further amplify the impact of immune checkpoint inhibitors in the treatment of non-small cell lung cancer.

First-Line Immune-Checkpoint Inhibitors in Non-Small Cell Lung Cancer: Current Landscape and Future Progress

Lung cancer is one of the most common cancers and the leading cause of cancer-related deaths worldwide. Most of these patients with non-small cell lung cancer (NSCLC) present with the advanced stage of the disease at the time of diagnosis, and thus decrease the 5-year survival rate to about 5%. Immune checkpoint inhibitors (ICIs) can act on the inhibitory pathway of cancer immune response, thereby restoring and maintaining anti-tumor immunity. There are already ICIs targeting different pathways, including the programmed cell death 1 (PD-1), programmed cell death ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) pathway. Since March 2015, the US Food and Drug Administration (FDA) approved nivolumab (anti-PD-1 antibody) as the second-line option for treatment of patients with advanced squamous NSCLC. Additionally, a series of inhibitors related to PD-1/PD-L1 immune-checkpoints have helped in the immunotherapy of NSCLC patients, and modified the original treatment model. However, controversies remain regarding the use of ICIs in a subgroup with targeted oncogene mutations is a problem that we need to solve. On the other hand, there are continuous efforts to find biomarkers that effectively predict the response of ICIs to screen suitable populations. In this review, we have reviewed the history of the continuous developments in cancer immunotherapy, summarized the mechanism of action of the immune-checkpoint pathways. Finally, based on the results of the first-line recent trials, we propose a potential first-line immunotherapeutic strategy for the treatment of the patients with NSCLC.

Clinical significance of tumour mutation burden in immunotherapy across multiple cancer types: an individual meta-analysis

BACKGROUND

Biomarkers for stratifying patients that could benefit from immune checkpoint inhibitors are necessary. Tumour mutation burden has recently become a promising biomarker in cancer, but the associations between tumour mutation burden and outcomes of immune checkpoint inhibitors treatment were not well-documented in present studies.

METHODS

We searched PubMed, Web of Science and EMBASE databases up to 1 October 2019. Studies evaluated the association between tumour mutation burden and clinical outcomes were included. Hazard ratios and odds ratios were applied to estimate the association of tumour mutation burden score with overall survival, progression-free survival and response rate, respectively. The best cut-off value was chosen by best discriminated overall survival using Contal and O'Quigley method.

RESULTS

Twenty-two studies involving 6171 patients in diverse cancers were included. The individual participant data meta-analysis demonstrated that high tumour mutation burden was associated with better overall survival (HR = 0.57, 95% CI = 0.50-0.64) and progression-free survival (HR = 0.50, 95% CI = 0.40-0.63) and higher response rate. The best cut-off values in each cancer type were 17.7/MB in non-small cell lung cancer, 7.9/MB in bladder cancer, 6.1/MB in melanoma, 12.3/MB in colorectal cancer, 6.9/MB in esophagogastric cancer, 10.5/MB in head and neck cancer. The pooled meta-analysis showed the prognosis value was robust and the sensitivity, specificity and area under the receiver operating characteristic curves in predicting response rates were 0.63, 0.71 and 0.73, respectively.

CONCLUSIONS

The present meta-analysis indicates tumour mutation burden is a promising predictor of immune checkpoint inhibitors therapy but the cut-off value differs in different cancers.

Genome and Transcriptome Biomarkers of Response to Immune Checkpoint Inhibitors in Advanced Solid Tumors

PURPOSE

Immune checkpoint inhibitors (ICI) have revolutionized the treatment of solid tumors with dramatic and durable responses seen across multiple tumor types. However, identifying patients who will respond to these drugs remains challenging, particularly in the context of advanced and previously treated cancers.

EXPERIMENTAL DESIGN

We characterized fresh tumor biopsies from a heterogeneous pan-cancer cohort of 98 patients with metastatic predominantly pretreated disease through the Personalized OncoGenomics program at BC Cancer (Vancouver, Canada) using whole genome and transcriptome analysis (WGTA). Baseline characteristics and follow-up data were collected retrospectively.

RESULTS

We found that tumor mutation burden, independent of mismatch repair status, was the most predictive marker of time to progression (P = 0.007), but immune-related CD8⁺ T-cell and M1-M2 macrophage ratio scores were more predictive for overall survival (OS; P = 0.0014 and 0.0012, respectively). While CD274 [programmed death-ligand 1 (PD-L1)] gene expression is comparable with protein levels detected by IHC, we did not observe a clinical benefit for patients with this marker. We demonstrate that a combination of markers based on WGTA provides the best stratification of patients (P = 0.00071, OS), and also present a case study of possible acquired resistance to pembrolizumab in a patient with non-small cell lung cancer.

CONCLUSIONS

Interpreting the tumor-immune interface to predict ICI efficacy remains challenging. WGTA allows for identification of multiple biomarkers simultaneously that in combination may help to identify responders, particularly in the context of a heterogeneous population of advanced and previously treated cancers, thus precluding tumor type-specific testing.

Prevalence of High Tumor Mutational Burden and Association With Survival in Patients With Less Common Solid Tumors

IMPORTANCE

Tumor mutational burden (TMB) is a potential biomarker associated with response to immune checkpoint inhibitor therapies. The prognostic value associated with TMB in the absence of immunotherapy is uncertain.

OBJECTIVE

To assess the prevalence of high TMB (TMB-H) and its association with overall survival (OS) among patients not treated with immunotherapy with the same 10 tumor types from the KEYNOTE-158 study.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study evaluated the prognostic value of TMB-H, assessed by Foundation Medicine (FMI) and defined as at least 10 mutations/megabase (mut/Mb) in the absence of immunotherapy. Data were sourced from the deidentified Flatiron Health-FMI clinicogenomic database collected up to July 31, 2018. Eligible patients were aged 18 years or older with any of the following solid cancer types: anal, biliary, endometrial, cervical, vulvar, small cell lung, thyroid, salivary gland, mesothelioma, or neuroendocrine tumor. Patients with microsatellite instability-high tumors were excluded from primary analysis. For OS analysis, patients were excluded if immunotherapy started on the FMI report date or earlier or if patients died before January 1, 2012, and patients were censored if immunotherapy was started later than the FMI report date. Data were analyzed from November 2018 to February 2019.

MAIN OUTCOMES AND MEASURES

Overall survival was analyzed using the Kaplan-Meier method and Cox proportional hazards model, adjusting for age, sex, cancer types, practice type, and albumin level.

RESULTS

Of 2589 eligible patients, 1671 (64.5%) were women, and the mean (SD) age was 63.7 (11.7) years. Median (interquartile range) TMB was 2.6 (1.7-6.1) mut/Mb, and 332 patients (12.8%) had TMB-H (≥10 mut/Mb). Prevalence of TMB-H was highest among patients with small cell lung cancer (40.0%; 95% CI, 34.7%-45.6%) and neuroendocrine tumor (29.3%; 95% CI, 22.8%-36.6%) and lowest was among patients with mesothelioma (1.2%; 95% CI, 0.3%-4.4%) and thyroid cancer (2.7%; 95% CI, 1.2%-5.7%). Adjusted hazard ratio for OS of patients not treated with immunotherapy with TMB-H vs those without TMB-H was 0.94 (95% CI, 0.77-1.13). Comparable results were observed when including patients with high microsatellite instability tumors and calculating OS from first observed antineoplastic treatment date.

CONCLUSIONS AND RELEVANCE

These findings suggest that prevalence of TMB-H varies widely depending on tumor type and TMB-H does not appear to be a factor associated with OS among patients across these cancer types treated in the absence of immunotherapy.

Harmonization of Molecular Testing for Non-Small Cell Lung Cancer: Emphasis on PD-L1

Comprehensive molecular testing plays a critical role in the choice of treatment for non-small lung cell cancer (NSCLC). The analysis of druggable alterations in EGFR, BRAF, MET, KRAS, ALK, ROS1, RET and NTRK1/2/3 genes is more or less standardized and can be achieved using a single diagnostic platform, e.g., next generation sequencing (NGS) or polymerase chain reaction (PCR). In contrast to above targets, PD-L1 testing requires the use of immunohistochemistry (IHC). There are multiple PD-L1 IHC assays, which utilize distinct antibodies and detection systems. These PD-L1 tests are tailored to distinct drugs, often rely on different thresholds and scoring guidelines, and are characterized by incomplete inter-laboratory and inter-observer reproducibility. Several studies evaluated the performance of PD-L1 RNA expression tests, as PCR-based RNA analysis is compatible with other NSCLC molecular testing platforms, can be performed in a semi-automated manner, and has a potential for proper standardization. These investigations revealed a correlation between PD-L1 protein and RNA expression; however, there were NSCLCs demonstrating decent amounts of PD-L1 transcript in the absence of PD-L1 IHC staining. Clinical studies are required to evaluate, which of the two PD-L1 testing approaches, i.e., RNA or protein expression measurement, has a better predictive value.

Morphological, immune and genetic features in biopsy sample associated with the efficacy of pembrolizumab in patients with non-squamous non-small cell lung cancer

INTRODUCTION

The usefulness of the histopathology of biopsy samples for predicting the efficacy of immunotherapy in non-squamous, non-small cell lung cancer (NSq NSCLC) patients remains unclear.

METHODS

We retrospectively investigated the associations between the histopathological features in biopsy samples and survival outcomes in advanced NSq NSCLC patients receiving pembrolizumab. NSq NSCLC was classified histopathologically as morphological adenocarcinoma or non-small cell carcinoma (NSCC: absence of definitive features of either adenocarcinoma or a squamous morphology). We investigated the association between the tumor morphological features and immune/genetic features by examining the tumor PD-L1 expression and tumor mutation burden (TMB).

RESULTS

Among 33 advanced NSq NSCLC patients with tumor PD-L1 scores ≥ 50% receiving pembrolizumab as first-line therapy, a biopsy diagnosis of NSCC was associated with a significantly longer progression-free survival [median 16.8 vs. 2.3 months; hazard ratio (HR) 0.26; 95% CI 0.10-0.62, P = 0.01] and overall survival (median NR vs. 10.1 months; HR 0.35; 0.12-0.97, P = 0.04) as compared to that of morphological adenocarcinoma. In an analysis of 367 biopsy samples, the NSCC group showed a higher percentage of samples with PD-L1 scores ≥ 50% than the morphological adenocarcinoma group (35% vs. 10%). The NSCC group (n = 8) also showed a significantly higher TMB than the morphological adenocarcinoma group (n = 7) (median 236 vs. 25 mutations/whole exome, P = 0.01).

CONCLUSION

Absence of definitive morphological features in a biopsy sample could be a useful predictor of the efficacy of pembrolizumab in NSq NSCLC patients with tumor PD-L1 scores ≥ 50%, as these tumors are likely to show high tumor PD-L1 expression and high TMB.

A Potential Biomarker of Combination of Tumor Mutation Burden and Copy Number Alteration for Efficacy of Immunotherapy in KRAS-Mutant Advanced Lung Adenocarcinoma

Objectives

The Kirsten Rat Sarcoma (KRAS) mutation is the commonest oncogenic drive mutation in lung adenocarcinoma (LUAD) and immunotherapy may be quite promising for KRAS-mutant LUAD. While the effects of tumor mutation burden (TMB) and copy number alteration (CNA) are poorly understood in this illness, our study aimed to explore the roles TMB and CNA play in the prediction of response to immune checkpoint inhibitor (ICI) therapy in advanced KRAS-mutant LUAD.

Methods

Mutation and clinical data were downloaded from cBioPortal. We evaluated KRAS mutation status and divided patients into different subgroups based on TMB and CNA cutoffs to investigate the predictive value of these biomarkers on ICI response.

Results

KRAS mutation with concurrent TP53 or STK11 mutations had higher TMB and CNA compared to KRAS mutation alone. The KRAS G12C and G > T mutation subgroups, with TP53 or STK11 co-mutation, also had higher TMB and CNA. We found that TMB and CNA were independently associated with progression-free survival (PFS) and durable clinical benefits (DCB); TMB was positively correlated with PFS (P = 0.0074) and DCB (P = 0.0008) while low CNA was associated with prolonged PFS (P = 0.0060) and DCB (P = 0.0018). However, TMB alone did not distinguish benefits among KRAS-mutant patients. Notably, when combining TMB and CNA, low TMB and high CNA revealed worse outcomes of ICI therapy (mPFS: 2.20m, P = 0.0023; proportion of DCB: 24%, P = 0.0001).

Conclusion

The combination of TMB and CNA provides more sensible and accurate prediction of ICI response than individual factors in KRAS-mutant LUAD. Moreover, low TMB and high CNA can be utilized as a potential biomarker to predict adverse outcome in KRAS-mutant LUAD.

Development of a novel prognostic score combining clinicopathologic variables, gene expression, and mutation profiles for lung adenocarcinoma

BACKGROUND

Integrating phenotypic and genotypic information to improve prognostic prediction is under active investigation for lung adenocarcinoma (LUAD). In this study, we developed a new prognostic model for event-free survival (EFS) and recurrence-free survival (RFS) based on the combination of clinicopathologic variables, gene expression, and mutation data.

METHODS

We enrolled a total of 408 patients from the Cancer Genome Atlas Lung Adenocarcinoma (TCGA-LUAD) project for the study. We pre-selected gene expression or mutation features and constructed 14 different input feature sets for predictive model development. We assessed model performance with multiple evaluation metrics including the distribution of C-index on testing dataset, risk score significance, and time-dependent AUC under competing risks scenario. We stratified patients into higher- and lower-risk subgroups by the final risk score and further investigated underlying immune phenotyping variations associated with the differential risk.

RESULTS

The model integrating all three types of data achieved the best prediction performance. The resultant risk score provided a higher-resolution risk stratification than other models within pathologically defined subgroups. The score could account for extra EFS-related variations that were not captured by clinicopathologic scores. Being validated for RFS prediction under a competing risks modeling framework, the score achieved a significantly higher time-dependent AUC as compared to that of the conventional clinicopathologic variables-based model (0.772 vs. 0.646, p value < 0.001). The higher-risk patients were characterized with transcriptional aberrations of multiple immune-related genes, and a significant depletion of mast cells and natural killer cells.

CONCLUSIONS

We developed a novel prognostic risk score with improved prediction accuracy, using clinicopathologic variables, gene expression and mutation profiles as input, for LUAD. Such score was a significant predictor of both EFS and RFS.

TRIAL REGISTRATION

This study was based on public open data from TCGA and hence the study objects were retrospectively registered.

[The use of immune checkpoint inhibitors in routine oncology]

Hintergrund

Die Einführung von Immuncheckpoint-Inhibitoren (ICI) hat die Behandlungskonzepte der Onkologie für eine Vielzahl von unterschiedlichen Krebsarten maßgeblich verändert. Dabei werden in der klinischen Routine v. a. humanisierte Antikörper gegen Immuncheckpoints wie „cytotoxic T‑lymphocyte associated protein 4“ (CTLA-4) oder „programmed cell death 1/programmed cell death ligand 1“ (PD1/PD-L1) eingesetzt.

Fragestellung

Übersicht zur Therapielandschaft mit Immuncheckpoint-Inhibitoren bei mehrheitlich soliden Tumoren in der Onkologie.

Material und Methoden

Darstellung und Diskussion aktueller Studienresultate, Einbezug aktueller Behandlungsempfehlungen und Zulassungsindikationen.

Ergebnisse

Sieben verschiedene Immuncheckpoint-Inhibitoren werden in der Onkologie therapeutisch eingesetzt: ein Anti-CTLA-4-Antikörper, 3 Anti-PD1-Antikörper und 3 Anti-PD-L1-Antiköper. FDA-Zulassung auf dem US-Markt für 17 verschiedene Tumorentitäten und einer agnostischen Indikation (Tumoren mit defizienter Mismatch-repair-Maschinerie/hohe Mikrosatelliteninstabilität). Langzeitremissionen sind in ca. zwei Drittel der Patienten mit Tumoransprechen möglich.

Schlussfolgerungen

Nutzen der Immuncheckpoint-Inhibitoren nur für einen Teil der behandelten Patienten. Primäre und sekundäre Resistenzmechanismen erst in Anfängen verstanden. Kombinationstherapien der Immuncheckpoint-Inhibitoren mit z. B. Chemotherapie, neuen Immuncheckpoint-Inhibitoren (z. B. Anti-LAG3-Antikörper) oder gezielten Therapien (z. B. CDK4/6, PARP-Inhibitoren) zur Verbesserung der Wirksamkeit werden in klinischen Studien untersucht. Verlässliche, prädiktive Marker sind dringend erforderlich.

Intratumoral Immunotherapy: From Trial Design to Clinical Practice

Systemic immunotherapies such as immune checkpoint blockade targeted at PD(L)1 and CTLA4 have demonstrated their ability to provide durable tumor responses and long-term overall survival benefits for some patients in several solid tumor types. However, a majority of patients remain resistant to these treatments and a significant proportion of them develop severe autoimmune and inflammatory adverse events. Preclinical studies have demonstrated that intratumoral injections of immunostimulatory products (oncolytics, pattern recognition receptor agonists,…) that are able to trigger type I IFN release and enhance tumor antigen presentation on immune cells could generate a strong antitumor immunity and overcome the resistance to systemic immune checkpoint blockade therapies. The intratumoral immunotherapy strategies that are currently in clinical development offer a unique therapeutic and exploratory setting to better understand the immune contexture across tumor lesions of patients with metastatic cancer. Also these local therapeutic products could turn cold tumors into hot and improve the response rates to cancer immunotherapies while diminishing their systemic exposure and toxicities. Intratumoral immunotherapies could prime or boost the immunity against tumors and therefore radically change the combinatorial therapeutic strategies currently pursued for metastatic and local cancers to improve their long-term survival. We aimed to review and discuss the scientific rationale for intratumoral immunotherapy, the challenges raised by this strategy in terms of drug development within clinical trials and the current state-of-the-art regarding the clinical practice of this innovative approach.

Association of tumour mutational burden with outcomes in patients with advanced solid tumours treated with pembrolizumab: prospective biomarker analysis of the multicohort, open-label, phase 2 KEYNOTE-158 study

BACKGROUND

Tumour mutational burden (TMB) has been retrospectively correlated with response to immune checkpoint blockade. We prospectively explored the association of high tissue TMB (tTMB-high) with outcomes in ten tumour-type-specific cohorts from the phase 2 KEYNOTE-158 study, which assessed the anti-PD-1 monoclonal antibody pembrolizumab in patients with selected, previously treated, advanced solid tumours.

METHODS

In the multi-cohort, open-label, non-randomised, phase 2 KEYNOTE-158 study, patients were enrolled from 81 academic facilities and community-based institutions across 21 countries in Africa, the Americas, Asia, and Europe. Eligible patients were aged 18 years or older, had a histologically or cytologically confirmed advanced (ie, unresectable or metastatic, or both) incurable solid tumour (eligible tumour types were anal, biliary, cervical, endometrial, mesothelioma, neuroendocrine, salivary, small-cell lung, thyroid, and vulvar), progression on or intolerance to one or more lines of standard therapy, had measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1) assessed by independent central radiological review, Eastern Cooperative Oncology Group performance status of 0 or 1, life expectancy of at least 3 months, adequate organ function, and a tumour sample for biomarker analysis. Participants were given pembrolizumab 200 mg intravenously every 3 weeks for up to 35 cycles. Tissue TMB (tTMB) was assessed in formalin-fixed paraffin-embedded tumour samples using the FoundationOne CDx assay (Foundation Medicine, Cambridge, MA, USA). The prespecified definition of tTMB-high status was at least 10 mutations per megabase. The primary endpoint was the proportion of patients with an objective response (complete or partial response) as per Response Evaluation Criteria in Solid Tumours (version 1.1) by independent central review. This prespecified analysis assessed the association between antitumour activity and tTMB in treated patients with evaluable tTMB data. Efficacy was assessed in all participants who received at least one dose of pembrolizumab, had evaluable tTMB data, and were enrolled at least 26 weeks before data cutoff (June 27, 2019), and safety was assessed in all participants who received at least one dose of pembrolizumab and had tTMB-high status. KEYNOTE-158 is registered at ClinicalTrials.gov, NCT02628067, and is ongoing.

FINDINGS

Between Jan 15, 2016, and June 25, 2019, 1073 patients were enrolled. 1066 participants were treated as of data cutoff (June 27, 2019), of whom 805 (76%) were evaluable for TMB, and 105 (13%) of 805 had tTMB-high status and were assessed for safety. 1050 (98%) of 1066 patients enrolled by at least 26 weeks before data cutoff, of whom 790 (75%) were evaluable for TMB and included in efficacy analyses. 102 (13%) of these 790 patients had tTMB-high status (≥10 mutations per megabase), and 688 (87%) patients had non-tTMB-high status (<10 mutations per megabase). Median study follow-up was 37·1 months (IQR 35·0-38·3). Objective responses were observed in 30 (29%; 95% CI 21-39) of 102 patients in the tTMB-high group and 43 (6%; 5-8) of 688 in the non-tTMB-high group. 11 (10%) of 105 patients had treatment-related serious adverse events. 16 (15%) participants had a grade 3-5 treatment-related adverse event, of which colitis was the only such adverse event that occurred in more than one patient (n=2). One patient had fatal pneumonia that was assessed by the investigator to be treatment related.

INTERPRETATION

tTMB-high status identifies a subgroup of patients who could have a robust tumour response to pembrolizumab monotherapy. tTMB could be a novel and useful predictive biomarker for response to pembrolizumab monotherapy in patients with previously treated recurrent or metastatic advanced solid tumours.

FUNDING

Merck Sharp & Dohme Corp, a subsidiary of Merck & Co, Inc.

Clinical biomarkers directing the management of patients with colon and lung cancer (beyond oncogene-addicted NSCLC)

Treatment personalisation plays a key role in the current management of patients with cancer. Several biomarkers have shown clinical utility and may guide therapeutic decisions. Amongst patients with lung cancer, the level of expression of programmed death ligand 1 (PD-L1) has both prognostic and predictive values in terms of response to the inhibition of programmed cell death protein 1 (PD-1). Depending on the clinical setting, the expression of PD-L1 ≥1% or ≥50% has been associated with improved outcomes amongst patients receiving pembrolizumab. Regarding patients with colorectal carcinoma, mutations in the KRAS oncogene predict the responsiveness to the inhibition of epidermal growth factor receptor (EGFR). Only patients with wild-type KRAS tumours derive benefit from cetuximab and panitumumab in terms of response and survival. In conclusion, future research should aim in the optimisation of the use of biomarker in the clinical practice in order to provide the optimal drug combination to each individual patient.

Cost-Effectiveness Analysis of Nivolumab Plus Ipilimumab vs. Chemotherapy as First-Line Therapy in Advanced Non-Small Cell Lung Cancer

Background: The CheckMate 227 trial has indicated that nivolumab plus ipilimumab compared with chemotherapy significantly increases long-term survival in the first-line setting of advanced non-small-cell lung cancer (NSCLC).

Methods: A Markov model was built to estimate the cost and effectiveness of nivolumab plus ipilimumab vs. chemotherapy as the first-line therapy in patients with advanced NSCLC based on outcomes data from the CheckMate 227 trial. We calculated the cost and health outcomes at a willingness-to-pay (WTP) threshold of $150,000 per quality adjusted life year (QALY) in populations with different programmed death ligand 1 (PD-L1) expression levels (≥50, ≥1, and <1%) or a high tumor mutational burden (TMB) (≥10 mutations per megabase). Sensitivity analysis were used to test the model stability.

Results: The outcomes showed that the incremental costs and QALYs by using nivolumab plus ipilimumab were $124180.76 and 1.16, $70951.42 and 0.53, $144093.63 and 0.83 for the advanced NSCLC patients with a PD-L1 expression ≥50%, ≥1%, and <1%, which led to an incremental cost-effective ratio (ICER) of $107403.72, $133732.20, and $172589.15 per QALY, respectively. For patients with a high TMB, nivolumab plus ipilimumab contributed an extra 2.04 QALYs at a cost of $69182.50 per QALY.

Conclusion: Nivolumab plus ipilimumab as first-line therapy makes a better cost-effective strategy than chemotherapy in advanced NSCLC patients with PD-L1 expression levels ≥50% and ≥1% or a high TMB, at a willingness-to-pay threshold of $150,000 per QALY, but not in the patients with a PD-L1 expression <1%.

Robust assessment of tumor mutational burden in cytological specimens from lung cancer patients

OBJECTIVES

Tumor mutational burden (TMB) has emerged as a promising predictive biomarker for immune checkpoint inhibitor therapy. While the feasibility of TMB analysis on formalin-fixed paraffin-embedded (FFPE) samples has been thoroughly evaluated, only limited analyses have been performed on cytological samples, and no dedicated study has investigated concordance of TMB between different sample types. Here, we assessed TMB on matched histological and cytological samples from lung cancer patients and evaluated the accuracy of TMB estimation in these sample types.

MATERIALS AND METHODS

We analyzed mutations and resulting TMB in FFPE samples and matched ethanol-fixed cytological smears (n = 12 matched pairs) by using a targeted next-generation sequencing assay (Oncomine™ Tumor Mutational Load). Two different variant allele frequency (VAF) thresholds were used to estimate TMB (VAF = 5% or 10%).

RESULTS

At 5% VAF threshold, 73% (107/147) of mutations were concordantly detected in matched histological and cytological samples. Discordant variants were mainly unique to FFPE samples (34/40 discordant variants) and mostly C:G > T:A transitions with low allelic frequency, likely indicating formalin fixation artifacts. Increasing the VAF threshold to 10% clearly increased the number of concordantly detected mutations in matched histological and cytological samples to 96% (100/106 mutations), and drastically reduced the number of FFPE-only mutations (from 34 to 4 mutations). In contrast, cytological samples showed consistent mutation count and TMB values at both VAF thresholds. Using FFPE samples, 2 out of 12 patients were classified as TMB-high at VAF cutoff of 5% but TMB-low at 10%, whereas cytological specimens allowed consistent patient classification independently from VAF cutoff.

CONCLUSION

Our results show that cytological smears provide more consistent TMB values due to high DNA quality and lack of formalin-fixation induced artifacts. Therefore, cytological samples should be the preferred sample type for robust TMB estimation.

Circulating T-cell Immunosenescence in Patients with Advanced Non-small Cell Lung Cancer Treated with Single-agent PD-1/PD-L1 Inhibitors or Platinum-based Chemotherapy

PURPOSE

CD28, CD57, and KLRG1 have been previously identified as markers of T-cell immunosenescence. The impact of immunosenescence on anti-PD(L)-1 (ICI) or platinum-based chemotherapy (PCT) in patients with advanced non-small cell lung cancer (aNSCLC) is unknown.

EXPERIMENTAL DESIGN

The percentage of CD28^-, CD57⁺, KLRG1⁺ among CD8⁺ T cells [senescent immune phenotype (SIP)] was assessed by flow cytometry on blood from patients with aNSCLC before single-agent ICI (discovery cohort). A SIP cut-off was identified by log-rank maximization method and patients with aNSCLC treated with ICI (validation cohort) or PCT were classified accordingly. Proliferation and functional properties of SIP⁺ CD8⁺ T cells were assessed in vitro.

RESULTS

In the ICI discovery cohort (N = 37), SIP cut-off was 39.5%, 27% of patients were SIP⁺. In the ICI validation cohort (N = 46), SIP⁺ status was found in 28% of patients and significantly correlated with worse objective response rate (ORR; 0% vs. 30%, P = 0.04), median progression-free survival (PFS) [1.8 (95% confidence interval (CI), 1.3-NR) vs. 6.4 (95% CI, 2-19) months, P = 0.009] and median overall survival, OS [2.8 (95% CI, 2.0-NR) vs. 20.8 (95% CI, 6.0-NR) months, P = 0.02]. SIP⁺ status was significantly associated with circulating specific immunephenotypes, in vitro lower CD8⁺ T cells proliferation, lower IL2 and higher TNFα and IFNγ production. In the ICI-pooled population (N = 83), SIP⁺ status did not correlate with any clinical characteristics and it was associated with significantly worse ORR, PFS, and OS. In PCT cohort (N = 61), 11% of patients were SIP⁺. SIP status did not correlate with outcomes upon PCT.

CONCLUSIONS

Circulating T-cell immunosenescence is observed in up to 28% of patients with aNSCLC and correlates with lack of benefit from ICI but not from PCT.See related commentary by Salas-Benito et al., p. 374.

New biomarkers for checkpoint inhibitor therapy

Immune checkpoint inhibitor blockade has vastly changed treatment paradigms and improved outcomes of many solid organ malignancies. The achievements of the last decade have transformed the outcomes of several tumour types, most notably metastatic melanoma. There are, however, still large numbers of patients who receive checkpoint inhibitor therapy and do not respond. In addition to potential lack of efficacy, checkpoint inhibitors also come with a unique and sometimes devastating side-effect profile. There exists a strong need for biomarkers to accurately predict response, improve treatment selection and avoid exposing patients to toxicity where there is minimal likelihood of response. There is a wide range of methodologies investigating predictive biomarkers in this space; in this review, we address the major putative biomarkers of interest. These include conventional serum tests such as lymphocyte indices and lactate dehydrogenase, and more novel research markers such as interleukin-6 and T receptor clonality. We discuss tumorous factors that may be of interest in certain tumour types, and finally gene expression profiling. Significant research continues into many of these potential predictive biomarkers in response to the emergent need to better select patients who will benefit from treatment.

Evaluation of Programmed Death Ligand 1 (PD-L1) Gene Amplification and Response to Nivolumab Monotherapy in Non-small Cell Lung Cancer

IMPORTANCE

Robust predictors for response to anti-programmed death 1 and its ligand (PD-1/PD-L1) immunotherapy in non-small cell lung cancer (NSCLC) are not fully characterized.

OBJECTIVE

To evaluate whether PD-L1 (CD274) copy number gains (CNGs), comprising amplification and polysomy, in pretreatment specimens assessed by fluorescence in situ hybridization are associated with response to nivolumab monotherapy in NSCLC.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter cohort study enrolled 200 patients, of whom 194 had assessable tumors, with advanced or recurrent NSCLC who were treated with nivolumab after progression following prior treatment at 14 institutions in Japan between July 2016 and December 2018. Median (interquartile range) duration of follow-up was 12.6 (5.6-20.4) months. Data were analyzed from December 2019 to February 2020.

EXPOSURES

Sequential nivolumab was given on day 1 of a 14-day cycle. Response was assessed every 4 cycles using Response Evaluation Criteria in Solid Tumors version 1.1.

MAIN OUTCOMES AND MEASURES

Overall response rate (ORR) according to the PD-L1 copy number status. Additional end points were progression-free survival, overall survival, and PD-L1 tumor proportion score (TPS) assessed by immunohistochemistry based on PD-L1 copy number status.

RESULTS

A total of 6 of the 200 patients were excluded because of poor-quality tumor specimens for the biomarker study, resulting in 194 assessable patients. Of these, 155 (79.9%) were men, with a median (range) age of 69 (43-83) years. PD-L1 CNGs were identified in 32 patients (16.5%), including 5 (2.6%) with amplification and 27 (13.9%) with polysomy. The ORR among patients with and without PD-L1 CNGs was 28.1% (95% CI, 13.7%-46.7%) and 17.9% (95% CI, 12.3%-24.7%), respectively. Although patients with PD-L1 polysomy did not demonstrate improved ORR (18.5% [95% CI, 6.3%-38.1%]) compared with those without PD-L1 CNGs, 4 of 5 patients (80.0% [95% CI, 28.4%-99.5%]) with PD-L1 amplification showed response, among whom median duration of response was not reached. Patients with PD-L1 amplification showed excellent survival outcomes for progression-free and overall survival. Overall, 3 PD-L1-amplified tumors (60.0%) showed PD-L1 TPS of at least 80%, but 2 (40.0%) had PD-L1 TPS of 15% or less.

CONCLUSIONS AND RELEVANCE

In this study, tumor PD-L1 amplification but not polysomy was associated with response to nivolumab monotherapy among patients with NSCLC. External validation with a larger sample size is warranted.

Choosing tumor mutational burden wisely for immunotherapy: A hard road to explore

Immunotherapy has revolutionized the treatment of cancer due to its remarkable efficacy and extensive survival benefit in multiple tumor types. However, predictive biomarkers are required to identify patients who are likely to respond to immunotherapy. Recently, tumor mutational burden (TMB) has been shown to be associated with clinical outcomes in diverse cancers, such as melanoma, non-small-cell lung cancer and colorectal cancer. Several studies have demonstrated that high TMB can effectively predict the objective response rate and progression-free survival, but the ability of TMB to predict overall survival is limited. Thus, the clinical utility of TMB as a predictive and prognostic biomarker in immunotherapy is currently controversial. Importantly, multiple factors can affect the accurate assessment of TMB and further interfere with its prediction of clinical outcomes. These factors include preanalytical factors such as sample status, analytical factors such as differences in platforms and methods for determining TMB and variability of cutoff values, and postanalytical factors such as inconsistent interpretation and reporting of results. In addition, the optimal definition and quantification of TMB are unclear and require harmonization and standardization for reliable clinical application. This review elaborates on the factors affecting TMB status in primary tumors, summarizes the clinical utility of TMB as a biomarker in immunotherapy, and evaluates the impact of each analysis stage on the accurate estimation of TMB, especially its quantification, aiming to facilitate TMB assessment in routine clinical settings.