Biomarkers of immunotherapy for non-small cell lung cancer.

Immunotherapy is revolutionizing the treatment of non-small cell lung cancer by targeting immune checkpoint proteins, including programmed death-1, programmed death ligand 1 and cytotoxic T-lymphocyte-associated antigen 4. Several immune checkpoint inhibitors, including programmed death ligand 1 inhibitors, programmed death-1 inhibitors and cytotoxic T-lymphocyte-associated antigen 4 inhibitors, were approved for the treatment of patients with advanced non-small cell lung cancer. Programmed death ligand 1 expression is currently the only predictive biomarker for immune checkpoint inhibitors to guide the treatment strategy in these patients. However, programmed death ligand 1 expression is not a perfect biomarker for predicting the efficacy of immunotherapy. Therefore, various biomarkers such as tumour mutation burden, tumour microenvironment, gut microbiome and T-cell receptor repertoire have been proposed to predict the efficacy of immunotherapy more accurately. Additionally, combining different biomarkers may provide a more accurate prediction of response to immunotherapy. This article reports the review of the latest evidence of the predictive marker of immunotherapy in patients with advanced non-small cell lung cancer.

Tumor microenvironment-mediated immune profiles and efficacy of anti-PD-L1 antibody plus chemotherapy stratified by DLL3 expression in small-cell lung cancer.

BACKGROUND: Delta-like ligand 3 (DLL3) is a therapeutic target in small-cell lung cancer (SCLC). However, how DLL3 expression status affects the tumor microenvironment (TME) and clinical outcomes in SCLC remains unclear. METHODS: This retrospective study included patients with postoperative limited-stage (LS)-SCLC and extensive-stage (ES)-SCLC treated with platinum and etoposide (PE) plus anti-programmed cell death ligand 1 (PD-L1) antibody. We investigated the relationship of DLL3 expression with TME, mutation status, tumor neoantigens, and immunochemotherapy. RESULTS: In the LS-SCLC cohort (n = 59), whole-exome sequencing revealed that DLL3High cases had significantly more neoantigens (P = 0.004) and a significantly higher rate of the signature SBS4 associated with smoking (P = 0.02) than DLL3Low cases. Transcriptome analysis in the LS-SCLC cohort revealed that DLL3High cases had significantly suppressed immune-related pathways and dendritic cell (DC) function. SCLC with DLL3High had significantly lower proportions of T cells, macrophages, and DCs than those with DLL3Low. In the ES-SCLC cohort (n = 30), the progression-free survival associated with PE plus anti-PD-L1 antibody was significantly worse in DLL3High cases than in DLL3Low cases (4.7 vs. 7.4 months, P = 0.01). CONCLUSIONS: Although SCLC with DLL3High had a higher neoantigen load, these tumors were resistant to immunochemotherapy due to suppressed tumor immunity by inhibiting antigen-presenting functions.

Clinicopathological characteristics and molecular analysis of lung cancer associated with ciliated muconodular papillary tumor/bronchiolar adenoma.

Ciliated muconodular papillary tumor/bronchiolar adenoma (CMPT/BA) is a recently introduced benign lung tumor. It remains unclear whether CMPT/BA is associated with a specific type of lung cancer (LC). We studied the clinicopathological characteristics and genetic profiles of the coexisting primary LC and CMPT/BA (LCCM) cases. We identified eight LCCM (0.4%) from the resected Stage 0-III primary LC (n = 1945). The LCCM cohort was male-dominant (n = 8), elderly (median 72 years old), and most were smokers (n = 6). In addition to the adenocarcinoma (n = 8), we detected two squamous cell carcinomas and one small cell carcinoma-in some cases, multiple cancer. The target sequence/whole exome sequence (WES) revealed no shared mutations between CMPT/BA and LC. One exceptional case was invasive mucinous adenocarcinoma harboring an HRAS mutation (I46N, c.137T>A), but it was likely to be a single nucleotide polymorphism based on variant allele frequency (VAF). Other driver mutations in LC included EGFR (InDel, n = 2), BRAF(V600E) (n = 1), KRAS (n = 2), GNAS (n = 1), and TP53 (n = 2). BRAF(V600E) was the most frequent mutation in CMPT/BA (60%). In contrast, LC showed no specific trend in driver gene mutations. In conclusion, our study revealed differences in the gene mutation profiles of CMPT/BA and LC in coexisting cases, suggesting mostly independent clonal tumorigenesis of CMPT/BA from LC.

Performance of Japanese patients in registrational studies.

INTRODUCTION: The accelerated development of lung cancer treatments has resulted in a single global study that is sufficient for a new agent and indication to be approved. Not all new treatments predominate globally, and differences in standards of care may influence the efficacy of treatments in the real world. METHODS: The results from Japanese domestic trials and global trials that included a subset population of Japanese patients were evaluated for 18 genomic targeted agents and immune therapies approved after 2000. The results were collected from drug applications that were reviewed for treatment approval in Japan. RESULTS: Japan is one of the first countries to approve and fully reimburse new agents around the world. Alectinib and nivolumab, which were first developed by Japanese pharmaceutical companies, were evaluated in an independent domestic trial, which resulted in their early approval. For most other indications, 1.1-15.8% of the patients who participated in pivotal registration studies were Japanese, and their treatment results were comparable to those of the overall population. Overall survival was less likely to be improved by four agents for which the post-protocol therapy might have been different in Japan than in other countries. CONCLUSIONS: Overall, a positive result in a global trial was emulated in Japanese patients and led to the approval of a new standard treatment in Japan. Early approvals were attained by either participating in the global registrational study or conducting a domestic phase II study. The higher efficacy of new agents may be an issue in the future, as Japanese patients had early access to the new agent and may receive better treatment after the trial.

Prognostic impact of peripheral blood neutrophil to lymphocyte ratio in advanced-stage pulmonary large cell neuroendocrine carcinoma and its association with the immune-related tumour microenvironment.

BACKGROUND: The prognostic value of the neutrophil-to-lymphocyte ratio (NLR) with large cell neuroendocrine carcinoma (LCNEC) patients remains unclear. Thus, we performed a retrospective study to examine the relationship between the pretreatment NLR and clinical outcome in advanced LCNEC patients and the impact of the immune-related tumour microenvironment (TME). METHODS: This retrospective study included 63 advanced LCNEC patients who had received chemotherapy. We collected clinical data and investigated the TME status (CD4, CD8, CD20 and FOXP3). RESULTS: The overall survival of the patients with a low NLR (<5) was significantly longer than those with a high NLR (≥5) (14.9 vs. 5.2 months; p < 0.001). A multivariate analysis identified a high NLR as a predictor of a poor prognosis (HR, 3.43; 95% CI, 1.73-6.79; p < 0.001). The NLR was inversely correlated with tumoural and stromal CD8-positive tumour-infiltrating lymphocytes (tumoural: r = -0.648, p = 0.005, stromal: r = -0.490, p = 0.046). CONCLUSIONS: A high NLR was associated with a poor prognosis in advanced LCNEC patients. Our study revealed that the NLR can reflect the TME, at least in part, suggesting that the NLR plays an important role not only as a clinical outcome predictor but also as a tumour immune status indicator.

Efficacy and risk of cytotoxic chemotherapy in extensive disease-small cell lung cancer patients with interstitial pneumonia.

BACKGROUND: Small cell lung cancer (SCLC) is characterized by a high propensity for metastases and a poor prognosis irrespective of high sensitivity for initial chemotherapy. Although interstitial pneumonia (IP) is one of risk factors for lung cancer, efficacy of cytotoxic chemotherapy for patients with SCLC with IP remains unclear. Our study aims to evaluate the efficacy of systemic chemotherapy and assess risk of acute exacerbation (AE)-IP with cytotoxic drugs for extensive disease (ED)-SCLC patients with IP. METHODS: We performed a retrospective study of 192 consecutive ED-SCLC patients with IP (n = 40) and without IP (n = 152) between 2008 and 2016. RESULT: 31 of 40 ED-SCLC patients with IP and 130 of 152 patients without IP received systemic chemotherapy. The efficacy of chemotherapy in patients with IP was not inferior to that in patients without IP (overall survival [OS], 7.1 [95% confidence interval (CI): 0.2-14.0] vs. 10.0 [95% CI: 8.2-11.8] months, P = 0.57). Pretreatment serum levels of lactate dehydrogenase (LDH; 651.7 ± 481.0 vs. 301.4 ± 110.7 U/mL, P = 0.01) and C-reactive protein (CRP; 8.9 ± 9.6 vs. 1.8 ± 1.8 U/mL, P = 0.008) were correlated with developed AE-IP in the ED-SCLC patients with IP. CONCLUSION: Systemic chemotherapy was effective even in ED-SCLC patients with IP. However, the risk of developed AE-IP that was high in patients with IP and should be evaluated using serum LDH and CRP levels before initial chemotherapy.

Efficacy of Platinum-Based Chemotherapy for Relapsed Small-Cell Lung Cancer after Amrubicin Monotherapy in Elderly Patients and Patients with Poor Performance Status.

BACKGROUND: Previous studies have shown amrubicin to be an effective first- or second-line treatment option for small-cell lung cancer (SCLC). However, there have been few studies reporting the efficacy of platinum-based chemotherapy after amrubicin therapy. We aimed to evaluate the efficacy of platinum-based chemotherapy as second-line treatment for elderly patients and those with SCLC with poor performance status (PS) previously treated with amrubicin monotherapy. METHODS: The records of SCLC patients who received platinum-based chemotherapy as a second-line chemotherapy after first-line treatment with amrubicin monotherapy were retrospectively reviewed and the treatment outcomes were evaluated. RESULTS: A total of 48 patients were enrolled in this study. Forty-one patients (85%) received carboplatin plus etoposide. The overall response rate was 39.6%. The median progression-free survival and overall survival were 3.7 and 7.6 months, respectively. The efficacy of the platinum-based regimen did not differ with the type of relapse after amrubicin monotherapy. The most common adverse events were hematological toxicities, including grade 3 or 4 neutropenia (38%), leukopenia (33%), and thrombocytopenia (10%). CONCLUSIONS: Platinum-based chemotherapy is potentially a valid treatment option for elderly patients or those with extensive-stage SCLC with poor PS as second-line chemotherapy, who progressed after first-line treatment with amrubicin monotherapy.

Smoking History as a Predictor of Pemetrexed Monotherapy in Patients with Non-Squamous Non-Small Cell Lung Cancer.

BACKGROUND: Pemetrexed monotherapy has come to be recognized as the standard of care for second-line therapy of non-squamous non-small cell lung cancer (NSCLC). Thymidylate synthase (TS) expression is recognized as a potential predictor of the response to pemetrexed-based chemotherapy in patients with advanced NSCLC. The purpose of this study was to identify useful predictors of the response to pemetrexed other than TS expression. METHODS: The records of non-squamous NSCLC patients without driver mutations who received pemetrexed monotherapy as a second or later line of chemotherapy at Kitasato University Hospital between March 2009 and October 2015 were retrospectively reviewed, and the treatment outcomes were evaluated. RESULTS: In the 116 patients with non-squamous NSCLC, the overall response rate and progression-free survival (PFS) were 10.3% and 2.1 months, respectively. The disease control rate and PFS differed significantly among current smokers and never-smokers/former light smokers (44.9 vs. 65.8%, and 1.8 vs. 4.0 months, respectively). Furthermore, multivariate analysis identified Eastern Cooperative Oncology Group Performance Status and smoking status as independent predictors of the PFS. CONCLUSION: The clinical data obtained in this study may provide a valuable basis for the use of smoking status as a predictor of pemetrexed monotherapy in wild-type NSCLC patients.

Clinical significance of inter-assay discrepancy in PD-L1 evaluation for the efficacy of pembrolizumab in advanced NSCLC with high PD-L1 expression.

INTRODUCTION: Programmed cell death ligand-1 (PD-L1) expression is a predictive biomarker for the efficacy of anti-programmed cell death receptor-1/PD-L1 antibodies in advanced non-small cell lung cancer (NSCLC). Although several assays have been approved for evaluating PD-L1 expression status, inter-assay discordance has been observed between some assays. The clinical significance of these discrepancies is still unclear. METHODS: We retrospectively reviewed treatment-naïve NSCLC patients whose PD-L1 expression was evaluated using both 22C3 and SP142 assays. Among those, efficacy analysis was performed for patients with PD-L1 tumor proportion score (TPS) ≥ 50 % (22C3), who had received first-line pembrolizumab monotherapy. Additionally, transcriptome analysis was conducted in the available tumors with TPS ≥ 50 % to investigate the distinct immune profiles that accompany inter-assay discordance. RESULTS: In total, 611 patients were eligible. Among 198 patients with TPS ≥ 50 %, 91 (46 %) had tumor cell score ≤ 1 (SP142, i.e., inter-assay discrepancy). In the 52 patients who received first-line pembrolizumab monotherapy, treatment efficacy was significantly lower in patients with the discrepancy than that in those without (objective response rate: 18 % vs. 83 %, p < 0.001; median progression-free survival [months]: 3.2 vs. 8.3, p < 0.001). Transcriptome analysis revealed significantly more CD274 splice variants with aberrant 3'-terminal sequences in tumors with the inter-assay discrepancy than in those without. CONCLUSION: The inter-assay discrepancy in the PD-L1 status of tumor cells between the 22C3 and SP142 assays, reflecting an imbalance in the CD274 splice variants, could be a biomarker for primary resistance against pembrolizumab monotherapy in high PD-L1-expressing NSCLCs.

Identification of inflamed-phenotype of small cell lung cancer leading to the efficacy of anti-PD-L1 antibody and chemotherapy.

BACKGROUND: Platinum etoposide plus anti-programmed cell death ligand-1 (PD-L1) antibody therapy is the standard of care for extensive-stage small cell lung cancer (ES-SCLC). However, patient characteristics associated with the efficacy of the combination therapy in SCLC are unclear. METHODS: We retrospectively reviewed post-surgical limited-stage (LS)-SCLC and ES-SCLC patients treated with atezolizumab plus carboplatin and etoposide (ACE). The association between SCLC subtypes based on transcriptomic data and pathological findings, including CD8-positive tumor-infiltrating lymphocyte (TIL) status, was investigated in the LS-SCLC cohort. The association between the efficacy of ACE therapy, pathological subtypes, and TIL status was evaluated in the ES-SCLC cohort. RESULTS: The LS-SCLC cohort (N = 48) was classified into four SCLC subtypes (ASCL1 + NEUROD1 [SCLC-A + N, N = 17], POU2F3 [SCLC-P, N = 15], YAP1 [SCLC-Y, N = 10], and inflamed [SCLC-I, N = 6]) based on transcriptomic data. SCLC-I showed enriched immune-related pathways, the highest immune score (CD8A expression and T-cell-inflamed gene expression profiles), and epithelial-mesenchymal transition (EMT), in transcriptional subtypes. Immunohistochemical staining (IHC) showed that SCLC-I had the highest density of CD8-positive TILs in transcriptional subtypes. In the ES-SCLC cohort, the efficacy of ACE therapy did not differ according to pathological subtypes. The progression-free survival (PFS) of TILHigh patients was significantly longer than that of TILLow patients (PFS: 7.3 months vs. 4.0 months, p < 0.001). CONCLUSION: Tumors with a high density of TILs, which represent the most immunogenic SCLC subtype (SCLC-I), based on transcriptomic data could benefit from ACE therapy.

Whole-genome sequencing reveals the molecular implications of the stepwise progression of lung adenocarcinoma.

The mechanism underlying the development of tumors, particularly at early stages, still remains mostly elusive. Here, we report whole-genome long and short read sequencing analysis of 76 lung cancers, focusing on very early-stage lung adenocarcinomas such as adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma. The obtained data is further integrated with bulk and spatial transcriptomic data and epigenomic data. These analyses reveal key events in lung carcinogenesis. Minimal somatic mutations in pivotal driver mutations and essential proliferative factors are the only detectable somatic mutations in the very early-stage of AIS. These initial events are followed by copy number changes and global DNA hypomethylation. Particularly, drastic changes are initiated at the later AIS stage, i.e., in Noguchi type B tumors, wherein cancer cells are exposed to the surrounding microenvironment. This study sheds light on the pathogenesis of lung adenocarcinoma from integrated pathological and molecular viewpoints.

Concurrent High PD-L1 Expression and CD8+ Immune Cell Infiltration Predict PD-1 Blockade Efficacy in Advanced EGFR-Mutant NSCLC Patients.

OBJECTIVES: The effectiveness of PD-1 blockade therapy in advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) is limited. We investigated whether patient characteristics, PD-L1 expression, and immune cell (IC) status in the tumor microenvironment (TME) were associated with PD-1 blockade therapy outcomes. MATERIALS AND METHODS: We retrospectively reviewed patients with advanced EGFR-mutant NSCLC treated with PD-1 blockade (nivolumab or pembrolizumab) between January 2016 and March 2018. The PD-L1 expression tumor proportion score (TPS) and types and distribution of ICs (CD8, PD-1, CD204, tumoral, and stromal) in the TME were analyzed. RESULTS: Among 57 EGFR-mutant NSCLC patients treated with PD-1 blockade, 39 patients had sufficient tissues for analyzing the TME. The overall response rate (ORR) of PD-1 blockade was 12.3%. Only tumoral CD8 positive (CD8+) IC status was significantly associated with the response (median tumoral CD8+ICs: 299/mm2 vs. 115/mm2, P < .01). Among the 6 patients with concurrent high PD-L1 expression (TPS: ≥ 50%)/high tumoral CD8+ ICs (≥ 205/mm2), 5 (83.3%) showed a response and a significantly longer progression-free survival (PFS) (PFS: 9.4M vs. 1.8M, P < .01). In contrast, none of the 7 patients with high PD-L1 expression/low tumoral CD8+ICs (<205/mm2) showed a response. CONCLUSION: Concurrent high PD-L1 expression and high tumoral CD8+ ICs could predict the response and longer PFS of PD-1 blockade therapy in EGFR-mutant patients.

Safety Implications of Switching Pembrolizumab Dosage From 200 mg Every 3 Weeks to 400 mg Every 6 Weeks in Patients With Advanced NSCLC.

INTRODUCTION: Administration of 400 mg pembrolizumab every 6 weeks (400 mg Q6W) has been approved on the basis of the results of simulated pharmacokinetic modeling and exposure-response analyses. Nevertheless, the safety of switching dosage from 200 mg every 3 weeks (Q3W) to 400 mg Q6W during treatment remains unclear. METHODS: This study involved patients (N = 45) with advanced NSCLC, in whom the pembrolizumab dosage was switched from 200 mg Q3W to 400 mg Q6W between August 2020 and November 2021 in our institute. RESULTS: At the time of switching, the median age of the patients was 71 (range: 32-84) years, and 32 patients (71.1 %) were males. The median number of cycles of 200 mg Q3W before switching was six (range: 1-31). After switching, new or worsening immune-related adverse events (irAEs) occurred in 17 of the 45 patients (37.8%) within three cycles. The irAEs were pneumonitis in 11 patients (24.4%), diarrhea in three patients (6.7%), renal dysfunction in two patients (4.4%), adrenal dysfunction in two patients (4.4%), a skin rash in one patient (2.2%), fulminant type 1 diabetes mellitus in one patient (2.2%). CONCLUSIONS: The switching of pembrolizumab dosage from 200 mg Q3W to 400 mg Q6W resulted in the occurrence of new or worsening irAEs, in particular, pneumonitis, in the early cycles even in patients who had received stable treatment with 200 mg Q3W.

Nivolumab versus pembrolizumab in previously-treated advanced non-small cell lung cancer patients: A propensity-matched real-world analysis.

OBJECTIVE: Nivolumab and pembrolizumab have been the standard of care in patients with previously treated advanced non-small cell lung cancer (NSCLC). This study aimed to compare the efficacy and safety of nivolumab and pembrolizumab. MATERIALS AND METHODS: We retrospectively reviewed data of advanced NSCLC patients with PD-L1 (Programmed death-ligand 1) [clone:22C3] positive tumors (Tumor proportion score [TPS] ≥ 1%) who had been treated with nivolumab or pembrolizumab as second- or subsequent line from 2015 to 2021.Propensity score matching was performed to reduce potential selection bias. We analyzed the clinical outcomes including objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAEs). RESULTS: Among a total of 202 eligible patients, 72 pairs of patients from each group were identified after propensity score matching. There were no significant differences in ORR, PFS, and OS between the two agents (nivolumab vs. pembrolizumab: ORR, 23.6% vs. 20.8%, median PFS, 3.7 months vs. 4.6 months, hazard ratio [HR] 1.02; 95% confidence interval [CI], 0.71 to 1.46; p = 0.92, and median OS, 27.4 months vs. 19.6 months, HR 0.78; 95% CI, 0.51 to 1.20; p = 0.24). Additionally, PFS was similar between the treatments in the PD-L1 TPS ≥ 50% subgroup (median PFS, 3.7 months vs. 4.6 months, HR 0.94; 95% CI, 0.56 to 1.59; p = 0.82) and PD-L1 TPS 1-49% subgroup (median PFS, 3.7 months vs.4.6 months, HR 1.13; 95% CI, 0.69 to 1.85; p = 0.61). There was also no significant difference in the frequency of grade ≥ 3 irAEs (9.7% vs. 11.1%; p = 1.0). CONCLUSION: There is no significant difference in the efficacy and safety between nivolumab and pembrolizumab in advanced NSCLC patients with PD-L1-positive tumors in the subsequent line setting.

Baseline PD-L1 expression and tumour-infiltrated lymphocyte status predict the efficacy of durvalumab consolidation therapy after chemoradiotherapy in unresectable locally advanced patients with non-small-cell lung cancer.

BACKGROUND: Chemoradiotherapy (CRT) followed by durvalumab treatment improved prognosis in unresectable locally advanced non-small-cell lung cancer (LA-NSCLC). This study aimed to evaluate whether the status of the immune-related tumour microenvironment (TME) at baseline associates with the efficacy. METHODS: This retrospective study evaluated immune-related TME factors, including programmed cell death ligand 1 (PD-L1) (clone: 22C3) expression on tumour cells and the density of CD8-positive tumour-infiltrating lymphocytes (TILs) at pre-CRT in patients with unresectable LA-NSCLC treated with CRT only (CRT alone group) and those treated with CRT followed by durvalumab (Durva group). RESULTS: A total of 551 patients were included (N = 113 in the Durva group). Progression-free survival (PFS) in the Durva group was significantly greater than that in the CRT alone group (not reached [NR] vs 12.9 months; p = 0.002). In the CRT alone group, neither PD-L1 expression nor TIL status affected PFS; in contrast, in the Durva group, high density of CD8-positive TILs (TILHigh ≥100/mm2) and PD-L1-positive expression (tumour proportion score ≥1%; PD-L1+) was significantly associated with longer PFS (TIL: NR vs 9.5 months; p = 0.002; and PD-L1: NR vs 7.7 months; p = 0.003). On the other hand, in patients with epidermal growth factor receptor mutations or anaplastic lymphoma kinase rearrangements, there was no significant difference in PFS between the groups (Durva vs CRT alone: 9.9 months vs 14.0 months; p = 0.77). CONCLUSIONS: PD-L1+ and TILHigh at baseline could be predictive markers of the efficacy of CRT followed by durvalumab.

Lactic acid promotes PD-1 expression in regulatory T cells in highly glycolytic tumor microenvironments.

The balance of programmed death-1 (PD-1)-expressing CD8+ T cells and regulatory T (Treg) cells in the tumor microenvironment (TME) determines the clinical efficacy of PD-1 blockade therapy through the competition of their reactivation. However, factors that determine this balance remain unknown. Here, we show that Treg cells gain higher PD-1 expression than effector T cells in highly glycolytic tumors, including MYC-amplified tumors and liver tumors. Under low-glucose environments via glucose consumption by tumor cells, Treg cells actively absorbed lactic acid (LA) through monocarboxylate transporter 1 (MCT1), promoting NFAT1 translocation into the nucleus, thereby enhancing the expression of PD-1, whereas PD-1 expression by effector T cells was dampened. PD-1 blockade invigorated the PD-1-expressing Treg cells, resulting in treatment failure. We propose that LA in the highly glycolytic TME is an active checkpoint for the function of Treg cells in the TME via upregulation of PD-1 expression.

Smoking History Predicts High Presence of TILs and Efficacy of PD-1 Blockade in PD-L1 Expression-negative Non-small Cell Lung Cancer Patients.

BACKGROUND/AIM: Programmed death-ligand 1 (PD-L1) expression on tumor cells is a predictive biomarker of programmed cell death 1 (PD-1) blockade therapy. This study sought to clarify predictors of the efficacy of nivolumab in non-small cell lung cancer (NSCLC) patients with PD-L1 expression-negative tumors. PATIENTS AND METHODS: We retrospectively reviewed the records of advanced NSCLC patients between January 2016 and April 2019, and investigated the predictive marker of nivolumab including the status of CD8+ tumor infiltrating lymphocytes (TILs). RESULTS: A total of 70 NSCLC patients were included. Overall response rate (ORR) and progression-free survival (PFS) were better in patients with a heavy smoking history (smoking index: SI≥600) than in those without (SI<600) [ORR: 20.6% vs. 2.8%, (p=0.02), and PFS: 2.4 months vs. 1.8 months, (p=0.04)]. A high density of CD8+ TILs was significantly associated with a heavy smoking history (p=0.04). Conlusion: Heavy smoking history (SI≥600), which was correlated with a large number of CD8+ TILs, could be a predictor of the efficacy of nivolumab in NSCLC patients with PD-L1 expression-negative tumors.

Clinical characteristics of advanced non-small cell lung cancer patients with EGFR exon 20 insertions.

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations (Exon20ins) account for 4-12% of all EGFR mutations in non-small cell lung cancer (NSCLC) patients. Data on the differences in clinical characteristics between patients with Exon20ins and major mutations (M-mut) such as exon 19 deletion and L858R are limited. We retrospectively reviewed advanced NSCLC patients with EGFR mutations, who were treated with systemic therapy between January 2011 and December 2019. We identified 23 patients with Exon20ins and 534 patients with M-mut. In Exon20ins patients, the median age was 60 (range 27-88) years, and females and never-smokers were predominant. Clinical characteristics were similar in the two groups. In Exon20ins patients, 17 patients received platinum doublet as first-line therapy, and the overall response rate (ORR) and median progression-free survival (mPFS) were 11.8% and 8.9 months. Additionally, seven patients received conventional EGFR-tyrosine kinase inhibitors (TKIs), and eight patients anti-PD-1 antibodies in any-line therapy. ORR and mPFS of EGFR-TKIs and anti-PD-1 antibodies were 0%, 2.2 months and 25%, 3.1 months, respectively. Overall survival was significantly shorter in Exon20ins patients than in M-mut patients (29.3 vs. 43.4 months, p = 0.04). The clinical outcomes in Exon20ins patients were not satisfactory compared to M-mut patients.

Differential Immune-Related Microenvironment Determines Programmed Cell Death Protein-1/Programmed Death-Ligand 1 Blockade Efficacy in Patients With Advanced NSCLC.

INTRODUCTION: Programmed death-ligand 1 (PD-L1) expression is not a completely reliable predictive marker of the efficacy of anti-programmed cell death protein-1 (PD-1)/PD-L1 therapy in patients with advanced NSCLC. Immune-related tumor microenvironment (TME) is classified into four different types based on the tumor-infiltrating lymphocyte (TIL) status and PD-L1 expression. METHODS: We retrospectively reviewed patients with advanced NSCLC treated with anti-PD-1/PD-L1 therapy between 2015 and 2019. We investigated the association between the efficacy of anti-PD-1/PD-L1 therapy, the types of TME based on PD-L1 (clone: 22C3) expression, the density of CD8-positive TILs assessed by immunohistochemistry, and mutational profiles by next-generation sequencing. RESULTS: Overall, 228 patients were included in the analysis. The patients were classified into the following four groups: type I: PD-L1High (tumor proportion score ≥ 50%)/TILHigh (≥85/mm2; n = 73); type II: PD-L1Low (tumor proportion score < 50%)/TILLow (<85/mm2; n = 70); type III: PD-L1High/TILLow (n = 37); and type IV: PD-L1Low/TILHigh (n = 48). The objective response rate (ORR) and progression-free survival (PFS) of anti-PD-1/PD-L1 therapy clearly differed according to the different TME types (ORR and PFS; type I: 64%, 14.5 mo; type II: 12%, 2.1 mo; type III: 24%, 3.6 mo; type IV; 41%, 10.8 mo). In patients with PD-L1High tumors, type I tumors had significantly better ORR and PFS than type III tumors (ORR: p < 0.001 and PFS: p < 0.001). The presence of TP53 and KRAS mutation was related to the density of CD8-positive TILs and PD-L1 expression, respectively. CONCLUSIONS: Differential types of TME, including PD-L1 expression and TIL status, could accurately predict the efficacy of anti-PD-1/PD-L1 therapy.