Non-small Cell Lung Cancer Cohort Research Articles

A phase Ib study of abemaciclib in combination with pembrolizumab for patients (pts) with stage IV Kirsten rat sarcoma mutant (KRAS-mut) or squamous non-small cell lung cancer (NSCLC) (NCT02779751): Interim results.

9562 Background: Abemaciclib is an orally administered, selective small molecule cyclin-dependent kinase 4 and 6 inhibitor. In preclinical models, abemaciclib induced intratumor immune inflammation and synergized with PD-1 blockade to enhance antitumor efficacy in anti-PD-L1 refractory disease. Here, we report the safety and antitumor activity of abemaciclib plus the approved NSCLC treatment pembrolizumab in 2 cohorts for pts with nonsquamous and squamous NSCLC. Methods: Eligible pts for this nonrandomized, open-label, multicohort, phase 1b study were either chemotherapy-naive with ≥ 1% tumor cell (TC) PD-L1 staining, KRAS-mut nonsquamous NSCLC (Cohort A) or had a squamous subtype and received ≤ 1 prior platinum-containing chemotherapy regimen (Cohort B) for metastatic NSCLC. Primary endpoint was safety; secondary objectives included objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Results: Twenty-five pts with NSCLC were enrolled in each cohort. Most pts (68%) in Cohort B had received 1 prior line of chemotherapy. Safety profiles observed in both cohorts were largely consistent with previous reports for abemaciclib and pembrolizumab monotherapy. Grades 3/4 AEs in Cohorts A and B, respectively, included ALT increase (6 pts [24%]/ 0 pts), diarrhea (3 pts [12%]/ 0 pts), neutropenia (3 pts [12%]/ 0 pts), and pneumonitis (3 pts [12%]/ 1 pt [4%]). Six pts in Cohort A (24%) and 2 pts in Cohort B (8%) had a confirmed partial response for a disease control rate (CR+PR+SD) of 52% and 64%, respectively. In Cohort A, the ORR in pts with strong (≥50% TC) PD-L1 staining (n = 13) was 31% vs. 17% in pts with weak (1-49% TC) PD-L1 expression (n = 12). Median PFS and OS were 7.6 months (95% CI: 1.6, NR) and 22.0 months (95% CI: 9.9, NR) in Cohort A and 3.3 months (95% CI: 1.4, 5.2) and 6.0 months (95% CI: 3.7, 13.1) in Cohort B, respectively. Conclusions: Abemaciclib plus pembrolizumab resulted in a numerical higher rate of transaminase elevations and pneumonitis. Antitumor activity was remarkable in the KRAS-mut nonsquamous NSCLC but not noticeably higher as compared to historical data for pembrolizumab monotherapy. Clinical trial information: NCT02779751 .

Cyclooxygenase inhibitor use during checkpoint immunotherapy and effect on time to progression and overall survival for metastatic melanoma and non-small cell lung cancer patients.

e22034 Background: Immune checkpoint inhibitors (ICIs) improve survival outcomes in metastatic melanoma and non-small cell lung cancer (NSCLC). Preclinical evidence suggests that overexpression of cyclooxygenase-2 (COX2) in tumors facilitates immune evasion through prostaglandin E2 production and that COX inhibition synergizes with ICIs to promote antitumor T-cell activation. This study investigates whether concurrent COX inhibitor (COXi) use during ICI treatment is associated with improved time-to-progression (TTP), objective response rate (ORR) and overall survival (OS) in metastatic melanoma and NSCLC patients. Methods: We retrospectively reviewed 90 metastatic melanoma and 37 metastatic NSCLC patients, treated only with ICI between 2011 and 2019. Differences in TTP and OS by COXi use were compared using Kaplan-Meier and Cox regression. Interaction between COXi use and neutrophil-lymphocyte ratio (NLR) was examined. Independent radiology review per RECIST v1.1 was performed. Results: For melanoma patients, median TTP was significantly prolonged in COXi users (245 v 100.5 days, p = .0002). On multivariate analysis (MVA), COXi use associated with increased TTP (HR 0.36, 95% CI: 0.2 – 0.66, p = 0.001) when adjusted for age, pretreatment NLR, and gender. For NSCLC patients, COXi use also associated with increased TTP on MVA (HR 0.45; 95% CI: 0.21 – 0.97; p = 0.042) adjusted for age. ORR at 6-months was significantly higher in patients who received concurrent COXi compared to those that did not in both melanoma (58.6% v 19.2%, p = 0.0005) and NSCLC (73.7% v 33.3%, p = 0.036) cohorts. COXi use was associated with improved OS in NSCLC patients on MVA (HR 0.3; 95% CI: 0.12 – 0.78; p = 0.013), but not in melanoma patients. In the melanoma cohort, high pretreatment NLR of > 5 associated with decreased TTP on MVA (HR 3.21, 95% CI: 1.64 – 6.3; p = 0.0007). However, for melanoma patients with high NLR > 5, COXi use significantly associated with increased TTP (HR 0.08, 95% CI: 0.03 – 0.25); but in melanoma patients with low NLR ≤5, there was no effect on TTP (HR 0.65, 95% CI: 0.32-1.32). Similar outcomes were found in an adjusted melanoma cohort after RECIST review. Conclusions: Our study suggests that use of COXi concurrent with ICI is significantly associated with longer TTP and improved ORR at 6-months in metastatic melanoma and NSCLC patients. NSCLC patients using COXi had prolonged OS. Furthermore, COXi use appears to reverse the negative prognostic effect of a high NLR by prolonging TTP in melanoma patients.

Digital pathology to evaluate PD-L1 IHC scoring as a predictor of outcome with second-line avelumab treatment in patients with non-small cell lung cancer (NSCLC).

e21539 Background: Assessment of programmed death ligand-1 (PD-L1) protein expression using immunohistochemistry (IHC)-based tests is currently the only approved biomarker guiding treatment of non-small cell lung cancer (NSCLC) with checkpoint inhibitors. Robust scoring guidelines and suitable cut-offs should be defined specifically for each PD-L1 IHC assay and are critical for appropriate treatment decisions. Methods: We retrospectively applied a novel digital pathology (DP) solution that mimics the conventional tumor proportion scoring (TPS) of PD-L1. The exploratory DP solution was developed and validated using samples from 340 patients enrolled in the first- and second-line (1L and 2L) NSCLC cohorts of the avelumab phase 1 JAVELIN Solid Tumor trial (NCT01772004) and 792 patients with NSCLC enrolled in the avelumab phase 3 JAVELIN Lung 200 trial (NCT02395172). Efficacy analyses were conducted for overall survival (OS) and progression-free survival (PFS) using the full analysis set with evaluable imaging data (n = 136 and n = 544, respectively). Results: Comparison of DP and conventional, semiquantitative pathologist scoring resulted in a high correlation overall (Spearman correlation coefficient, 0.86), with comparable performance for prediction of outcome to treatment with avelumab in 2L NSCLC. Consistent with conventional scoring, median OS and median PFS in avelumab-treated patients increased with higher PD-L1 expression cut-offs: in patients with ≥1%, ≥50%, and ≥80% PD-L1 expression on tumors cells, median OS was 10.0 months (95% CI: 8.6-14.3), 13.8 months (95% CI: 9.6-20.4) and 18.5 months (95% CI: 9.6-not estimable), respectively; median PFS, 3.1 months (95% CI: 2.7-4.9), 5.5 months (95% CI: 2.8-8.3) and 5.6 months (95% CI: 2.8-9.9). Conclusions: Our results demonstrate the technical feasibility, robustness, and utility of DP in scoring PD-L1 IHC in clinical trial samples, achieving comparable performance to conventional, semiquantitative pathologist scoring. Furthermore, our study supports the manual pathologist scoring algorithm (TPS scoring) in NSCLC and the selection of higher cut-offs for the PD-L1 IHC Ab clone 73-10.

Genomic correlates and classification of PD-L1 status in non-small cell lung cancer.

e21578 Background: Programmed cell death 1 (PD-L1) is the first FDA-approved predictive biomarker for non-small cell lung cancer (NSCLC) patients treated with PD-(L)1 blockade therapy. Herein, we aim to identify potential anti-PD-L1 treatment-related biomarkers through evaluating the correlation between the PD-L1 expression level, clinical characteristics, and the mutational profile of a large Chinese NSCLC cohort. Methods: Genomic profiling of tumor biopsies from a total of 808 Chinese NSCLC patients, including 651 adenocarcinomas (ADCs) and 157 squamous cell carcinomas (SCCs), was performed using next-generation sequencing by targeting 425 cancer-relevant genes. Immunohistochemical analysis was used to evaluate PD-L1 protein expression using PD-L1 antibodies including DAKO 22C3 ( N= 695) and DAKO 28-8 ( N= 113), respectively. Results: The PD-L1 positive ( > 1%) rate was 49.2% in ADCs and 52.9% in SCCs, respectively. PD-L1 expression (22C3) was associated with the male gender( p< 0.01) and lymph node metastasis ( p= 0.048) in ADCs but not in SCC patients. PD-L1 expression (22C3) was inversely correlated with KRAS wildtype ( p< 0.001) and EGFR exon 19 deletion( p< 0.01) in ADC, while it was negatively associated with TP53 oncogenic mutations ( p= 0.049) in SCC. Copy number variation analysis revealed that MDM2 amplification ( p= 0.027), 1q gain ( p= 0.012), and 5q deletion ( p< 0.01) negatively correlated with PD-L1 expression, whereas PD-L1 and PD-L2 amplification ( p< 0.001 and p< 0.0001) were positively associated with PD-L1 expression in ADCs. In SCCs, PD-L1 expression (22C3) was negatively associated with copy number gain in EGFR ( p= 0.040), MDM2 ( p= 0.044), 14q ( p= 0.032), and 20q ( p= 0.026), along with PTPRD loss (p = 0.015) and 19p deletion (p = 0.025). However, it was positively associated with 9p amplification ( p< 0.01) and 13q deletion ( p= 0.019). Plus, KIF5B- RET ( p= 0.006) appeared to be inversely related to the PD-L1 expression levels (22C3) in ADCs alone. In addition, these predicted biomarkers were used to delineate the receiver operating characteristic (ROC) calculation to discriminate between PD-L1 low and high (22C3, 50%) with an AUC score of 0.779. Lastly, PD-L1 expression (28-8) did not show significant correlation with any detected oncogenic mutations, but negatively correlated with NKX2-1 gain ( p= 0.0379) and 9q deletion ( p= 0.0379) in ADCs. Conclusions: This study revealed the correlation between PD-L1 protein expression, clinical features, and mutational traits in NSCLC patients, and provided a classifier for PD-L1 expression prediction.

Immune checkpoint inhibitors (ICI) response in metastatic non-small cell lung cancer (NSCLC) patients with WNT pathway mutations (APC/CTNNB1).

e15137 Background: APC and CTNNB1 mutations (mut) lead to an aberrant activation of the WNT pathway which has been linked to lack of benefit of immunotherapy in patients (pts) with lung cancer. Our aim is to describe the pts’ characteristics of a NSCLC cohort with APC or CTNNB1 mut and their association with outcomes (Overall survival [OS] and Progression-Free-Survival [PFS]) when treated with ICI. Methods: We selected NSCLC pts with mut in APC or CTNNB1 by targeted NGS (tissue), whole exome sequencing (tissue) or Guardant 360(plasma) between January 2014 and October 2019. Functionality of mut and β-catenin protein expression by immunohistochemistry (IHC) were correlated with outcome. Results: We identified a total of 37 patients with 44 mutually-exclusive mutations in APC (31) or CTNNB1 (6), 25 adenocarcinomas (68%). Of APC mut cohort, 16 had pathogenic mut (52%) and 15 of unknown significance (48%). All 6 CTN NB1 mut were known pathogenic. Median OS (mOS) in metastatic setting was 21.6 months (m) (CI95% 14.9-NR), without differences between APC and CTNNB1 groups (HR 1.5, p = 0.4) or when stratified by mut functionality (HR 1.1, p = 0.8). Globally, 21 pts received treatment with ICI (57%, 19 APC, 2 CTNNB1), median PFS (mPFS) was 5.43m (1.8-21.7), with trend for shorter mPFS in CTNNB1 mut (mPFS 1.7m) vs. APC mut (mPFS 6.6m, HR 1.5, p = 0.1). Among patients treated with ICI, 8 (38%) had coexisting driver targetable alterations ( EGFR, ERBB2 or MET) and 13 (62%) other functional mut were found ( TP53, KRAS, STK11, BRCA2, ATM). mPFS was 3.9m (1.8-NR) in the subgroup with driver mut vs. 6.6m (1.4-NR) for remaining pts (HR 1.36, p = 0.5). In 15 pts β-catenin IHC was performed, being positive in 7 cases (47%), 4 of them received ICI with a mPFS 12.1m. Conclusions: In our experience, benefit with ICI is not influenced by the presence of APC mut, and small numbers of CTNNB1 cohort limit conclusive statements. Additional studies are required to assess WNT pathway activation on top of genomics and correlate with the ICI efficacy.

Characterising the impact of pneumonia on outcome in non-small cell lung cancer: identifying preventative strategies.

BackgroundInfections remain a part of the natural course of cancer, and lung cancer patients often present with some form of respiratory infection that can lead to their ultimate demise.MethodsData was gathered concerning all unplanned hospital admissions (UHAs) to our centre from three separate patient cohorts; non-small cell lung cancer (NSCLC) patients (cohort 1), “other cancer” patients (breast, prostate, colon) (cohort 2) and all non-cancer patients (cohort 3).ResultsAcross the three cohorts, there were 455, 1,190 and 54,158 individual patient UHAs to our centre respectively. Within the NSCLC cohort, 164 UHAs were as a direct result of pneumonia (36.0%), compared to 1.3% and 2.2% in the other two cohorts (P<0.0001). In-hospital mortality and length of hospital stay were significantly higher in the pneumonia sub-group of NSCLC patients only compared with the other two patient cohorts (P<0.0001 and P=0.011 respectively). Within the NSCLC cohort, Patient age, pneumococcal vaccination status, pneumonia admission, smoking status and specific tumour stages were identified as significant independent risk factors for in-hospital mortality. Odds ratios of 0.160 for positive vaccination status and 9.522 for pneumonia admission indicate that for NSCLC patients admitted to hospital with a pneumonia without previous pneumococcal vaccination in the last 5 years, the odds of death were almost 60-fold higher.ConclusionsVigilance for infection, early diagnosis with adequate assessment and efforts to identify a culprit organism should be a priority when faced with these patients. Infection prevention strategies should be further explored to address this high mortality risk in NSCLC.

The Population-based Impact of Adjuvant Chemotherapy on Outcomes in T2N0M0 Non-Small Cell Lung Cancer.

The value of adjuvant chemotherapy in T2N0M0 non-small-cell lung cancer (NSCLC) is unclear. Some current guidelines suggest adjuvant chemotherapy be considered for patients with tumors ≥4 cm. Prior population-based evaluations lacked lung cancer-specific survival (LCSS) and health insurance status. The authors aimed to identify predictors of adjuvant chemotherapy use and assess its real-world benefit in T2N0M0 NSCLC. The authors included patients who underwent surgery for T2N0M0 NSCLC in a large Canadian province with universal health care between 2004 and 2015, grouping cases by adjuvant chemotherapy receipt. They identified predictors of chemotherapy use with logistic regression and correlates of overall survival (OS) and LCSS using Cox regression. The authors analyzed 967 patients. The median age was 68 years (interquartile range, 61 to 74), 455 (47%) were men, and 164 (17%) received adjuvant chemotherapy. Sex, tumor location, and laterality were similar between groups. Younger age, lower Charlson comorbidity score, large cell histology, and tumor size ≥4 cm were associated with a higher likelihood of chemotherapy receipt (all P<0.05). In the entire cohort and in the ≥4 and ≥5 cm subgroups, chemotherapy improved OS but not LCSS on univariate analysis. Chemotherapy was not associated with OS or LCSS in multivariate analysis (OS hazard ratio [HR], 0.925; 95% confidence interval [0.693-1.236], P=0.598, 0.725 [0.454-1.157], P=0.177 in the ≥4 cm group; LCSS HR, 1.196 [0.843-1.695], P=0.316, 0.917 [0.533-1.577], P=0.754 in the ≥4 cm group). Adjuvant chemotherapy was not associated with improved survival in this population-based T2N0M0 NSCLC cohort, even for ≥4 or ≥5 cm tumors, suggesting that it has a limited role in real-world practice.

Tumor-associated exosomal miRNA biomarkers to differentiate metastatic vs. nonmetastatic non-small cell lung cancer.

Exosomal microRNAs (miRNAs) are proposed to be excellent candidate biomarkers for clinical applications. However, little is known about their potential value as diagnostic biomarkers for metastatic non-small cell lung cancer (NSCLC). In this study, microarrays were used to determine distinct miRNA profiles of plasma exosomes in a discovery cohort of healthy donors, metastatic NSCLC and nonmetastatic NSCLC patients. Three potential candidate miRNAs were selected based on the differential expression profiles. The discovery set data were validated by quantitative real-time polymerase chain reaction using a validation cohort. NSCLC patients (n = 80) and healthy controls (n = 30) had different exosome-related miRNA profiles in plasma. Results demonstrated that the level of let-7f-5p was decreased in plasma exosomes of NSCLC patients (p < 0.0001). Further analysis of three differentially expressed miRNAs revealed that miR-320a, miR-622 and let-7f-5p levels could significantly segregate patients with metastatic NSCLC from patients with nonmetastatic NSCLC (p < 0.0001, p < 0.0001 and p = 0.023, respectively). In addition, the combination of let-7f-5p, CEA and Cyfra21-1 generated an area under the curve (AUC) of 0.981 for the diagnosis of NSCLC patients, and the combination of miR-320a, miR-622, CEA and Cyfra21-1 had an AUC of 0.900 for the diagnosis of patients with metastatic NSCLC. This novel study demonstrated that plasma exosomal miRNAs are promising noninvasive diagnostic biomarkers for metastatic NSCLC.

Pembrolizumab for management of patients with NSCLC and brain metastases: long-term results and biomarker analysis from a non-randomised, open-label, phase 2 trial

We did a phase 2 trial of pembrolizumab in patients with non-small-cell lung cancer (NSCLC) or melanoma with untreated brain metastases to determine the activity of PD-1 blockade in the CNS. Interim results were previously published, and we now report an updated analysis of the full NSCLC cohort. This was an open-label, phase 2 study of patients from the Yale Cancer Center (CT, USA). Eligible patients were at least 18 years of age with stage IV NSCLC with at least one brain metastasis 5-20 mm in size, not previously treated or progressing after previous radiotherapy, no neurological symptoms or corticosteroid requirement, and Eastern Cooperative Oncology Group performance status less than two. Modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria was used to evaluate CNS disease; systemic disease was not required for participation. Patients were treated with pembrolizumab 10 mg/kg intravenously every 2 weeks. Patients were in two cohorts: cohort 1 was for those with PD-L1 expression of at least 1% and cohort 2 was patients with PD-L1 less than 1% or unevaluable. The primary endpoint was the proportion of patients achieving a brain metastasis response (partial response or complete response, according to mRECIST). All treated patients were analysed for response and safety endpoints. This study is closed to accrual and is registered with ClinicalTrials.gov, NCT02085070. Between March 31, 2014, and May 21, 2018, 42 patients were treated. Median follow-up was 8·3 months (IQR 4·5-26·2). 11 (29·7% [95% CI 15·9-47·0]) of 37 patients in cohort 1 had a brain metastasis response. There were no responses in cohort 2. Grade 3-4 adverse events related to treatment included two patients with pneumonitis, and one each with constitutional symptoms, colitis, adrenal insufficiency, hyperglycaemia, and hypokalaemia. Treatment-related serious adverse events occurred in six (14%) of 42 patients and were pneumonitis (n=2), acute kidney injury, colitis, hypokalaemia, and adrenal insufficiency (n=1 each). There were no treatment-related deaths. Pembrolizumab has activity in brain metastases from NSCLC with PD-L1 expression at least 1% and is safe in selected patients with untreated brain metastases. Further investigation of immunotherapy in patients with CNS disease from NSCLC is warranted. Merck and the Yale Cancer Center.

Circulating tumor DNA clearance predicts prognosis across treatment regimen in a large real-world longitudinally monitored advanced non-small cell lung cancer cohort

BackgroundAlthough growth advantage of certain clones would ultimately translate into a clinically visible disease progression, radiological imaging does not reflect clonal evolution at molecular level. Circulating tumor DNA (ctDNA), validated as a tool for mutation detection in lung cancer, could reflect dynamic molecular changes. We evaluated the utility of ctDNA as a predictive and a prognostic marker in disease monitoring of advanced non-small cell lung cancer (NSCLC) patients.MethodsThis is a multicenter prospective cohort study. We performed capture-based ultra-deep sequencing on longitudinal plasma samples utilizing a panel consisting of 168 NSCLC-related genes on 949 advanced NSCLC patients with driver mutations to monitor treatment responses and disease progression. The correlations between ctDNA and progression-free survival (PFS)/overall survival (OS) were performed on 248 patients undergoing various treatments with the minimum of 2 ctDNA tests.ResultsThe results of this study revealed that higher ctDNA abundance (P=0.012) and mutation count (P=8.5×10−4) at baseline are associated with shorter OS. We also found that patients with ctDNA clearance, not just driver mutation clearance, at any point during the course of treatment were associated with longer PFS (P=2.2×10−16, HR 0.28) and OS (P=4.5×10−6, HR 0.19) regardless of type of treatment and evaluation schedule.ConclusionsThis prospective real-world study shows that ctDNA clearance during treatment may serve as predictive and prognostic marker across a wide spectrum of treatment regimens.

Abstract A26: Towards the identification of novel tumor antigens in human lung cancer

Abstract Immunotherapy has changed the treatment paradigm for patients with lung cancer and other solid tumors, but little is known about the antigen specificities of the T cell residing in tumors. In order to identify novel shared tumor antigens, we have previously developed an algorithm that allows the inference of T-cell specificities based on shared motifs within the T-cell receptor (TCR) CDR3 sequences. Leveraging with a dataset of 789K CDR3 sequences from 178 HLA-typed non-small cell lung cancer (NSCLC) patients, we have found up to 40K motifs after applying stringent cutoffs. Publicly available CDR3 sequences from various tetramer databases assisted with robust assignments of unique T-cell clones from the NSCLC cohorts to known specificities. For example, we have identified and validated multiple tumor-infiltrating T-cell clones that are specific to viral antigens. Furthermore, the availability of HLA genotype results for our lung cancer cohorts facilitated prediction of motifs that are potentially “restricted” to a given HLA allele or supertype. Together with single cell-sorted T-cell clones from our Stanford NSCLC cohort (n = 5,448), we have narrowed down to 60 tumor-specific CDR3 motifs (wherein at least one Stanford sequence could be found) that are potentially restricted to the A02 allele. Within these top A02-enriched motifs, 49 candidates TCR alpha/beta pairs were identified. In an effort to find novel tumor antigens, we prioritized four top T-cell candidates and screened A02 yeast display libraries with distinct peptide length (8-11mer). Four rounds of repeated screens led to the enrichment of a few dominant mimotopes with similar sequences. Database search identified a near-perfect match to a peptide 9mer from the TMEM161A locus that is predicted to bind HLA-A02 with high affinity. Functionally, the synthetic TMEM161A peptide 9mer stimulated Jurkat cells expressing the specific TCR alpha/beta chains as well as the top mimotopes. In conclusion, our results highlight the robustness of our current pipeline for the identification of novel shared tumor antigens. The ongoing work involves further characterizing the functional state of these specific T cells within the tumor microenvironment. Citation Format: Shin-Heng Chiou, Diane Tseng, Xinbo Yang, Alexandre Reuben, Alana McSween, Julie Wilhelmy, Chunlin Wang, Joseph Shrager, Jianjun (Jay) Zhang, K. Christopher Garcia, Crystal Mackall, Mark M Davis. Towards the identification of novel tumor antigens in human lung cancer [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr A26.

CT-Based Radiomic Signature as a Prognostic Factor in Stage IV ALK-Positive Non-small-cell Lung Cancer Treated With TKI Crizotinib: A Proof-of-Concept Study.

Objectives: To identify a computed tomography (CT)-based radiomic signature for predicting progression-free survival (PFS) in stage IV anaplastic lymphoma kinase (ALK)-positive non-small-cell lung cancer (NSCLC) patients treated with tyrosine kinase inhibitor (TKI) crizotinib.Materials and Methods: This retrospective proof-of-concept study included a cohort of 63 stage IV ALK-positive NSCLC patients who had received TKI crizotinib therapy for model construction and validation. Another independent cohort including 105 stage IV EGFR-positive NSCLC patients was also used for external validation in EGFR-TKI treatment. We initially extracted 481 quantitative three-dimensional features derived from manually segmented tumor volumes of interest. Pearson's correlation analysis along with the least absolute shrinkage and selection operator (LASSO) penalized Cox proportional hazards regression was successively performed to select critical radiomic features. A CT-based radiomic signature for PFS prediction was obtained using multivariate Cox regression. The performance evaluation of the radiomic signature was conducted using the concordance index (C-index), time-dependent receiver operating characteristic (ROC) analysis, and Kaplan–Meier survival analysis.Results: A radiomic signature containing three features showed significant prognostic performance for ALK-positive NSCLC patients in both the training cohort (C-index, 0.744; time-dependent AUC, 0.895) and the validation cohort (C-index, 0.717; time-dependent AUC, 0.824). The radiomic signature could significantly risk-stratify ALK-positive NSCLC patients (hazard ratio, 2.181; P < 0.001) and outperformed other prognostic factors. However, no significant association with PFS was captured for the radiomic signature in the EGFR-positive NSCLC cohort (log-rank tests, P = 0.41).Conclusions: The CT-based radiomic features can capture valuable information regarding the tumor phenotype. The proposed radiomic signature was found to be an effective prognostic factor in stage IV ALK mutated nonsynchronous nodules in NSCLC patients treated with a TKI.

Immune Cell PD-L1 Colocalizes with Macrophages and Is Associated with Outcome in PD-1 Pathway Blockade Therapy.

Programmed death ligand 1 (PD-L1) is expressed in tumor cells and immune cells, and both have been associated with response to anti-PD-1 axis immunotherapy. Here, we examine the expression of PD-L1 to determine which cell type carries the predictive value of the test. We measured the expression of PD-L1 in multiple immune cells with two platforms and confocal microscopy on three retrospective Yale NSCLC cohorts (425 nonimmunotherapy-treated cases and 62 pembrolizumab/nivolumab/atezolizumab-treated cases). The PD-L1 level was selectively measured in different immune cell subsets using two multiplexed quantitative immunofluorescence panels, including CD56 for natural killer cells, CD68 for macrophages, and CD8 for cytotoxic T cells. PD-L1 was significantly higher in macrophages in both tumor and stromal compartment compared with other immune cells. Elevated PD-L1 in macrophages was correlated with high PD-L1 level in tumor as well as CD8 and CD68 level (P < 0.0001). High PD-L1 expression in macrophages was correlated with better overall survival (OS; P = 0.036 by cell count/P = 0.019 by molecular colocalization), while high PD-L1 expression in tumor cells was not. In nearly 500 non-small cell lung cancer (NSCLC) cases, the predominant immune cell type that expresses PD-L1 is CD68+ macrophages. The level of PD-L1 in macrophages is significantly associated with the level of PD-L1 in tumor cells and infiltration by CD8+ T cells, suggesting a connection between high PD-L1 and "hot" tumors. In anti-PD-1 axis therapy-treated patients, high levels of PD-L1 expression in macrophages are associated with longer OS and may be responsible for the predictive effect of the marker.

Vemurafenib in non-small-cell lung cancer patients with BRAFV600 and BRAFnonV600 mutations

BRAF mutations occurring in 1%-5% of patients with non-small-cell lung cancer (NSCLC) are therapeutic targets for these cancers but the impact of the exact mutation on clinical activity is unclear. The French National Cancer Institute (INCA) launched the AcSé vemurafenib trial to assess the efficacy and safety of vemurafenib in cancers with various BRAF mutations. We herein report the results of the NSCLC cohort. Tumour samples were screened for BRAF mutations in INCA-certified molecular genetic centres. Patients with BRAF-mutated tumours progressing after ≥1 line of treatment were proposed vemurafenib 960 mg twice daily. Between October 2014 and July 2018, 118 patients were enrolled in the NSCLC cohort. The primary outcome was the objective response rate (ORR) assessed every 8 weeks (RECIST v1.1). A sequential Bayesian approach was planned with an inefficacy bound of 10% for ORR. If no early stopping occurred, the treatment was of interest if the estimated ORR was ≥30% with a 90% probability. Secondary outcomes were tolerance, response duration, progression-free survival (PFS), and overall survival (OS). Of the 118 patients enrolled, 101 presented with a BRAFV600 mutation and 17 with BRAFnonV600 mutations; the median follow-up was 23.9 months. In the BRAFnonV600 cohort, no objective response was observed and this cohort was stopped. In the BRAFV600 cohort, 43/96 patients had objective responses. The mean Bayesian estimated success rate was 44.9% [95% confidence intervals (CI) 35.2%-54.8%]. The ORR had a 99.9% probability of being ≥30%. Median response duration was 6.4 months, median PFS was 5.2 months (95% CI 3.8-6.8), and OS was 10 months (95% CI 6.8-15.7). The vemurafenib safety profile was consistent with previous publications. Routine biomarker screening of NSCLC should include BRAFV600 mutations. Vemurafenib monotherapy is effective for treating patients with BRAFV600-mutated NSCLC but not those with BRAFnonV600 mutations. ClinicalTrials.gov identifier: NCT02304809.

Diabetes mellitus type 2 is associated with increased tumor expression of programmed death-ligand 1 (PD-L1) in surgically resected non-small cell lung cancer—A matched case-control study

ObjectivesProgrammed death-ligand 1 (PD-L1) expression is a biomarker for cancer immunotherapy. Diabetes mellitus type-2 is a comorbid disease associated with adverse outcomes in Non-Small Cell Lung Cancer (NSCLC). We aimed to investigate the differences in PD-L1 expression in diabetics. MethodsA matched case-control cohort of surgically-resected NSCLC was assembled from an early multicenter study (PMID: 19152440). PD-L1 immunohistochemistry (Clone 22C3) was graded by a tumor positive score (TPS) system (TPS0: no staining; TPS1: <1%; TPS2: 1–49%; TPS3: ≥50%). Variables showing significance at univariate survival analysis were fit in a Cox regression survival model. ResultsDiabetics (n=40) and nondiabetics (n=39) showed no differences in age, gender, cancer stage, and follow-up. NSCLCs were more likely PD-L1 positive in diabetics but with tumor positivity <50% (TPS0: 7.5 vs. 20.5%, TPS1: 35 vs. 25.6%, TPS2: 45 vs.23.1%, TPS3: 12.5 vs. 30.8%, respectively; P<0.05). In diabetics, squamous cell carcinomas (SCC) and adenocarcinomas were mainly TPS2 (65% vs. 20%) and TPS1 (50% vs. 26%), respectively. Peritumoral inflammation correlated with TPS (r=0.228), a relationship accentuated in diabetics (r=0.377, P<0.05) but diminished and non-significant in nondiabetics (r=0.136, P≥0.05). This association was stronger in SCC (r=0.424). Diabetes was associated with increased tumor recurrence (HR: 3.08; 95%CI: 1.027-9.23). ConclusionDiabetes is associated with an increase in peritumoral inflammation, PD-L1 positivity, and recurrence in NSCLC, more pronounced in SCC, suggesting the possibility of metabolic reprogramming and upregulation of PD-L1 by inducible pathways.

Evaluation of chemiluminescent immunoassay quantitative detection for pro-gastrin-releasing peptide (ProGRP) in serum and plasma.

ObjectiveTo evaluate a newly developed Hybiome ProGRP chemiluminescent assay.MethodsAnalytical sensitivity, precision, recovery, and equivalency of serum and plasma, serum stability, and complement interference of the Hybiome ProGRP assay were evaluated. Serum specimens from 318 individuals including 38 small cell lung cancer (SCLC), 65 non-small cell lung cancer (NSCLC), 53 benign lung diseases, and 162 healthy controls were assessed using the Hybiome ProGRP assay and Roche Elecsys ProGRP assay, and the results were compared.ResultsThe Hybiome ProGRP assay showed good analytical sensitivity, precision, and accuracy, and it showed equivalence between serum and plasma and serum stability. The methodological comparison results showed good correlation between the Hybiome and Roche assays (slope, 0.9889; intercept, 1.28). Both the Hybiome and Roche assays showed good ability to distinguish between SCLC and NSCLC. Based on 95% specificity in the NSCLC cohort, a clinical differentiation cut-off for separating SCLC from NSCLC patients was 114 pg/mL for the Hybiome assay and 117 pg/mL for the Roche assay; the AUC was 0.9166 and the sensitivity was 71.05% for Hybiome and 0.9045 and 76.32% for Roche, respectively.ConclusionThe Hybiome ProGRP chemiluminescent assay shows good analytical performance and good correlation with the Roche Elecsys ProGRP assay.

Abstract A043: NaPi2b expression in a large surgical non-small cell lung cancer cohort

Abstract Background: NaPi2b (SLC34A2) is a sodium-dependent phosphate transporter expressed in a high proportion of non-small cell lung cancer (NSCLC), especially adenocarcinoma, and ovarian carcinoma cases, as well as other tumour types. A clinical trial of the NaPi2b-targeting antibody drug conjugate XMT-1536 is currently underway. This study investigates NaPi2b expression in NSCLC emphasising correlations to histology. Methods: Tissue Microarrays (TMAs) were constructed using triplicate 1mm cores from FFPE primary NSCLC tumours resected by lobectomy or pneumonectomy with curative intent at Austin Health, Melbourne, Australia. Pathology review identified the best site for coring of tumour blocks. For IHC, TMAs were stained with an anti-human NaPi2b primary antibody (MERS67) on the Leica Bond RX auto-stainer and the H-score (0 – 300) calculated based on the percentage of tumour cells stained multiplied by the staining intensity (0 - 3+). The mean score of multiple cores was calculated. A high H-score was defined as ≥50. Results: High NaPi2b expression was seen in 153/439 (35%) of cases. High NaPi2b expression was determined in 132/215 (61%) of adenocarcinoma cases, while only 12/178 (7%) of squamous cell and 9/46 (20%) of other histology cases (p &amp;lt; 0.001, chi-square) had high expression. Considering adenocarcinoma subtypes, high NaPi2b was seen with 18/21 (86%) micropapillary, 35/61 (57%) solid, 3/13 (23%) mucinous, 54/84 (64%) acinar, 8/13 (62%) papillary, 9/9 (100%) lepidic and 3/9 (33%) adenosquamous. Overall high NaPi2b was seen in 56/95 (59%) with poor risk adenocarcinoma subtypes (micropapillary, solid, mucinous) and 71/106 (67%) with good risk subtypes (papillary, acinar, lepidic). High scores were more frequent for females (52% vs 27%; p &amp;lt; 0.001), never smokers vs smokers (63% vs 33%; p &amp;lt; 0.001), EGFR mutation vs wt (75% vs 22%; p &amp;lt; 0.001) and KRAS mutation vs wt (71% vs 22%; p &amp;lt; 0.001). There were no significant differences in expression considering stage, primary tumour diameter, FEV1 (% predicted) or level of PD-L1 expression. For the whole cohort, a high NaPi2b score was associated with improved overall survival on univariate analysis (median 58 months vs 36 months; HR 0.77 [95% CI 0.61-0.97], p=0.03), while for adenocarcinoma there was a trend for improved survival (median 54 months vs 35 months; HR 0.76 [95% CI 0.55-1.04], p=0.09), and for both high risk adenocarcinoma subtypes (micropapillary, solid) and good risk subtype (acinar), high NaPi2b expression was associated with a weak trend to better survival. On multivariable analysis, NaPi2b remained the strongest predictor of improved survival (HR 0.77, 95% CI 0.58 - 1.02, p=0.07), though stage remained the only statistically significant variable. Conclusion: In this large early stage surgical NSCLC cohort, a high level of NaPi2b expression was seen with adenocarcinoma histology and also across the range of adenocarcinoma subtypes. Female gender, never smokers, and EGFR mutations were independently predictive of high level expression. For the whole cohort, high level expression was associated with improved overall survival. There was a similar, but non-significant, trend for high level expression in adenocarcinoma cases to be associated with improved survival, which appeared to be the case for both high risk and good risk adenocarcinoma subtypes. Citation Format: Paul L Mitchell, Hui Yu, Gareth Rivalland, Khashayar Asadi, Rebecca Mosher, Fred Hirsch, Christopher Rivard. NaPi2b expression in a large surgical non-small cell lung cancer cohort [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A043. doi:10.1158/1535-7163.TARG-19-A043

Presence of allele frequency heterogeneity defined by ctDNA profiling predicts unfavorable overall survival of NSCLC.

The generation of subclonal (low-frequency) mutations is driven by tumor mutations and the relationship between the heterogeneity of tumor mutation abundance and non-small cell lung cancer (NSCLC) remains unknown. We investigate the role of allele frequency heterogeneity (AFH) defined by circulating tumor DNA (ctDNA) profiling in predicting prognosis in advanced NSCLC patients. Publicly available data set of POPLAR (N=211) and OAK (N=642) trials were used for analyzing. A low ratio of allele frequency (AF) of a mutation to the maximum-somatic-allele-frequency (MSAF) was used to define the presence of AFH. The prognostic value of AF/MSAF ratio that was below a defined cutoff point in overall survival (OS) was evaluated using Cox-proportional hazards regression; and the structural break point was determined by LOESS regression and Chow test. The derived AFH was also explored in an independent cohort (N=259) of advanced NSCLC receiving first-line EGFR-TKIs from the First Affiliated Hospital of Guangzhou Medical University. In the POPLAR and OAK cohort, low AF/MSAF ratio was found to be significantly associated with unfavorable OS in univariate and multivariate analysis. The structural break point analysis demonstrated that AF/MSAF <10% could yield the optimal value to stratify patients with poor OS, which was applied for defining the presence of AFH. The presence of AFH significantly correlated with unfavorable OS in advanced NSCLC regardless of treatment arms (overall: HR 1.52, immunotherapy: HR 1.81, chemotherapy: HR 1.32, all P<0.05). In the exploratory EGFR-TKIs cohort, the presence of AFH was also significantly associated with shorter OS (HR 1.72, P=0.039). Our results demonstrate that the presence of AFH predict unfavorable prognosis in advanced NSCLC despite which drug the patients used. The presence of AFH defined by ctDNA might provide an easily-accessible biomarker for risk stratification in the current clinical practice.

P1.01-19 Predictive and Prognostic Values of ctDNA Clearance in Osimertinib Treated Advanced Non-Small Cell Lung Cancer Cohort

P1.01-19 Predictive and Prognostic Values of ctDNA Clearance in Osimertinib Treated Advanced Non-Small Cell Lung Cancer Cohort

331P - A phase II study of abemaciclib in patients (pts) with brain metastases (BM) secondary to non-small cell lung cancer (NSCLC) or melanoma (MEL)

BackgroundAbemaciclib, a selective CDK4 & 6 inhibitor, demonstrated single-agent activity in NSCLC and melanoma (Patnaik et al., 2016). Clinical data demonstrate abemaciclib penetrates the blood brain barrier resulting in comparable concentrations in tissues and plasma (Sahebjam et al., 2016). MethodsStudy JPBO is a Simon 2-stage trial evaluating abemaciclib in 6pt cohorts with BM secondary to HR+ breast cancer, NSCLC, or melanoma. Here, we report NSCLC and melanoma cohorts. Pts with ≥1 new or not previously irradiated BM≥10mm or a progressive BM previously irradiated were eligible. Abemaciclib was orally administered BID on a continuous dosing schedule. Primary endpoint was objective intracranial response rate (OIRR; [confirmed CR+PR]) based on Response Assessment in Neuro-Oncology BM response assessment criteria (RANO-BM). Secondary endpoints included intracranial clinical benefit rate, PFS, OS, and safety. Results28 (NSCLC) and 23 (MEL) pts were enrolled and 23 (NSCLC) and 22 (MEL) were evaluable. Pts had a median of 2 prior systemic therapies in the metastatic setting. 35% (NSCLC) and 46% (MEL) of pts had prior whole brain radiotherapy. 35% (NSCLC) and 27% (MEL) pts had stereotactic radiotherapy. Median time from radiation to study enrollment was 4.8 (NSCLC) to 5.6 (MEL) months. No confirmed intracranial response was observed (OIRR 0% for both cohorts). 21.7% (NSCLC) and 13.6% (MEL) of pts showed a decrease in the sum of their intracranial target lesions. ICBR (CR+PR+SD persisting for > 6 months) was 26.1% (NSCLC) and 9.1% (MEL). Median PFS was 1.5 months (95% CI, 1.4-2.8) for NSCLC and 1.2 months (95% CI, 1.0-1.6) for MEL. Median OS was 7.1 months (95% CI, 3.7-9.4) for NSCLC and 2.9 months (95% CI, 1.2-4.3) for MEL. Based on efficacy results, enrollment closed at end of stage 1. Safety and tolerability were similar as previously reported for abemaciclib. ConclusionsThere was limited intracranial clinical activity for abemaciclib monotherapy in NSCLC and MEL pts in this study; OIRR and short median PFS suggest that no further studies for abemaciclib monotherapy are warranted in this pt population. Clinical trial identificationNCT02308020. Editorial acknowledgementMedical writing assistance was provided by Kristi Gruver, employee of Eli Lilly and Company. Legal entity responsible for the studyEli Lilly and Company. FundingEli Lilly and Company. DisclosureE. Le Rhun: Advisory / Consultancy, Research grant / Funding (institution), Oscar Lambert Center, Lille, FR: Mundipharma; Research grant / Funding (institution), University Hospital, Lille, FR: Amgen; Advisory / Consultancy, personal fees: Novartis; Advisory / Consultancy, personal fees: Daiichi Sankyo; Advisory / Consultancy, personal fees: Abbvie. G. Jerusalem: Advisory / Consultancy, Non-remunerated activity/ies, per patient investigator fee: Eli Lilly and Company; Research grant / Funding (self), Non-remunerated activity/ies, personal fees: Novartis; Research grant / Funding (self), Non-remunerated activity/ies, personal fees: Roche; Advisory / Consultancy, Non-remunerated activity/ies, personal fees: Pfizer; Advisory / Consultancy, personal fees: Celgene; Advisory / Consultancy, Non-remunerated activity/ies, personal fees: Amgen; Advisory / Consultancy, Non-remunerated activity/ies, personal fees: BMS; Advisory / Consultancy, personal fees: Puma Technology; Advisory / Consultancy, Non-remunerated activity/ies, personal fees: AstraZeneca; Advisory / Consultancy, personal fees: Daiichi Sankyo; Advisory / Consultancy, personal fees: Abbvie. D. Subramaniam: Advisory / Consultancy, personal fees: AstraZeneca; Advisory / Consultancy, personal fees: Takeda Oncology; Speaker Bureau / Expert testimony, Research grant / Funding (institution): Genentech. Y. Chen: Shareholder / Stockholder / Stock options, Full / Part-time employment, employee and stock options: Eli Lilly and Company. P.F. Conte: Research grant / Funding (self): Novartis; Travel / Accommodation / Expenses, travel grant: Eli Lilly and Company; Research grant / Funding (self): Roche; Research grant / Funding (self): AstraZeneca; Travel / Accommodation / Expenses, travel grant: Celgene; Travel / Accommodation / Expenses, travel grant: Tesaro. All other authors have declared no conflicts of interest.