Expanded molecular interrogation for potential actionable targets in non-squamous non-small cell lung cancer.

Despite improvements in overall survival (OS) and clinical responses of unprecedented duration with the use of therapeutic monoclonal antibodies that target PD-1 or PD-L1, the majority of patients with non-small cell lung cancer (NSCLC) fail to respond to PD-1/PD-L1 axis inhibitors. The genomic determinants of PD-1/PD-L1 inhibitor efficacy in NSCLC are incompletely understood and likely key to the development of novel personalized immunotherapy approaches. Through integrative analysis of multiple independent datasets of patients with KRAS-mutant lung adenocarcinoma (LUAC) - the most prevalent oncogenic driver event in LUAC- we identified three major disease subsets defined on the basis of co-occurring genomic events in STK11/LKB1 (the KL subgroup), TP53 (KP) and CDKN2A/B, the latter coupled with low expression of the TTF1 transcription factor (KC) (Skoulidis F et al., Cancer Discovery, 2015). STK11/LKB1 is somatically mutated in ~17% of LUAC and encodes a serine/threonine kinase with an established role in the regulation of cellular metabolism, growth and polarity. Gene set enrichment analysis of RNASeq data from the TCGA LUAC cohort indicated striking de-enrichment of multiple gene expression signatures pertaining to anti-tumor immunity in the KL subgroup, raising the possibility that inactivation of STK11/LKB1 may promote establishment of a non-T-cell inflamed immune microenvironment in lung adenocarcinoma. Indeed, STK11/LKB1-mutant LUAC exhibited significantly lower density of infiltrating CD3+ (P=0.0019) and CD8+ (P=0.0072) T-lymphocytes by automated quantitative immunohistochemistry (IHC) in a tumor microarray encompassing early stage, surgically resected, chemotherapy-naïve tumors with available whole exome sequencing (PROSPECT cohort). In an independent, unbiased analysis of a large dataset of 924 LUAC with comprehensive NGS-based genomic profiling and available tumor cell PD-L1 expression (Foundation Medicine dataset) seeking to identify candidate genomic drivers of immune evasion and immunotherapy resistance, STK11/LKB1 genomic alterations emerged as the only significantly enriched gene in PD-L1Negative;TMBIntermediate/High compared to PD-L1High Positive;TMBIntermediate/High tumors (adjusted P<0.001). Thus, establishment of a “cold” tumor immune microenvironment in STK11/LKB1-mutant NSCLC occurs despite the presence of an intermediate/high TMB. Based on these findings we further hypothesized that STK11/LKB1 genomic alterations may impact clinical responses to PD-1 blockade in lung adenocarcinoma. In order to address this critical question, we assembled five independent cohorts of non-squamous NSCLC patients treated with PD-1 axis inhibitors. Three independent retrospective cohorts were studied from members of the Stand Up to Cancer/American Cancer Society Lung Cancer Translational Dream Team (MD Anderson Cancer Center, Memorial Sloan Kettering Cancer Center, Dana-Farber Cancer Institute/Massachusetts General Hospital), collectively forming the SU2C cohort (N=174). A fourth cohort of 66 patients with PD-L1 positive (≥1%) non-squamous NSCLC (regardless of KRAS status) from MD Anderson Cancer Center (MDACC) was assessed to determine the impact of STK11/LKB1 genomic alterations on clinical outcomes with anti-PD-1/PD-L1 therapy in PD-L1-positive tumors. A fifth independent cohort of 44 patients with KRAS-mutant NSCLC (24 treated with nivolumab and 20 treated with docetaxel) from the CheckMate-057 (CM-057) international phase III randomized controlled trial was also analyzed. Objective response rates to PD-1 blockade differed significantly among KL (7.4%), KP (35.7%) and K-only (28.6%) subgroups (P<0.001) in the SU2C cohort and in patients treated with nivolumab in the CheckMate-057 phase III randomized controlled trial (0% vs 57.1% vs. 18.2%; P=0.047). In the SU2C cohort, KL LUAC exhibited shorter progression-free (P<0.001) and overall (P=0.0015) survival compared with KRASMUT;STK11/LKB1WT LUAC. Because non-mutational mechanisms can also account for STK11/LKB1 inactivation in LUAC, we further assessed expression of STK11/LKB1 by IHC in a subset of tumors for which archival tissue was available. KRASMUT;STK11/LKB1MUT (KL) tumors expressed low to undetectable levels of STK11/LKB1 protein, whereas KRASMUT;STK11/LKB1WT tumors displayed variable levels of STK11/LKB1 expression, with 17.6% having a STK11/LKB1 H-score of zero. Patients bearing STK11/LKB1-deficient tumors (STK11/LKB1MUTor STK11/LKB1WT and STK11/LKB1 H-score zero) exhibited significantly shorter PFS (HR 1.80; 95% CI, 1.15-2.82; P = 0.0094) and OS (HR 2.03; 95% CI, 1.13-3.65; P = 0.016) compared with those harboring STK11/LKB1-proficient tumors (STK11/LKB1WT and STK11/LKB1 H-score > 0). Therefore, quantitative IHC for STK11/LKB1 can capture STK11/LKB1-deficient tumors with intact STK11/LKB1 genomic locus and may enhance the predictive utility of STK11/LKB1 genomic alterations. Importantly, the impact of STK11/LKB1 mutations on clinical outcomes with PD-1/PD-L1 inhibitors extended to PD-L1 positive tumors. Among 66 PD-L1-positive (≥1%) non-squamous NSCLC treated with PD-1/PD-L1 inhibitors, STK11/LKB1-mutated tumors exhibited significantly lower objective response rates to PD-1/PD-L1 blockade compared with NSCLC with intact STK11/LKB1 (ORR 0% vs. 34.5%, P = 0.026) and dramatically shorter PFS (HR 4.76; 95% CI, 2.0-11.1, P = 0.00012, log-rank test) and OS (HR 14.3; 95% CI, 3.4-50.0, P < 0.0001, log-rank test). More recently, we also interrogated the impact of STK11/LKB1 genomic alterations on clinical outcomes with chemo-immunotherapy, the new standard of care for the first line treatment of patients with metastatic non-squamous NSCLC. Among 43 patients with metastatic non-squamous NSCLC (wild-type for EGFR and ALK) that received pemetrexed/carboplatin/pembrolizumab at MDACC. STK11/LKB1 alterations were associated with significantly lower objective response rate (31.3% vs. 65.6%, P=0.035) and shorter progression free survival (HR 2.73; 95% CI 1.15-6.48; P=0.018) compared to STK11/LKB1 wild-type tumors. Finally, in order to establish whether primary resistance to immunotherapy is causally linked with STK11/LKB1 inactivation, we generated Stk11/Lkb1-proficient/deficient isogenic derivatives of the LKR10 and LKR13 Kras-mutant murine LUAC cell lines using CRISPR/Cas9-mediated bi-allelic disruption of the Stk11/Lkb1locus, implanted them into the flanks of syngeneic recipient mice and randomized cohorts of tumor bearing mice to treatment with anti-PD-1 mAb (LKR10), anti-PD-L1 mAb (LKR13) or IgG control. Treatment with PD-1/PD-L1 axis inhibitors potently suppressed Stk11/Lkb1-proficient tumors in both the LKR13 and LKR10 models, whereas Stk11/Lkb1 deficient isogenic tumors were recalcitrant to PD-1 axis blockade. Therefore, in these immune-competent models of KRAS-mutant LUAC, loss of STK11/LKB1 directly promotes PD-1/PD-L1 inhibitor resistance, suggesting a causal role. In agreement with data from human tumors, significantly lower numbers of CD3+CD8+ and CD3+CD8+PD1+ T lymphocytes were present in Stk11/Lkb1-deficient murine tumors compared to their Stk11/Lkb1-proficient counterparts. Taken together, our results identify inactivating mutations in STK11/LKB1 as a highly prevalent genomic determinant of a “cold” tumor immune microenvironment and major driver of de novo resistance to PD-1/PD-L1 inhibitors in non-squamous NSCLC independently of TMB and tumor cell PD-L1 expression. Furthermore, attribution of a large fraction of primary resistance to PD-1 axis blockade in non-squamous NSCLC to inactivating mutations in a single tumor suppressor gene - and therefore potentially to a single molecular mechanism - paves the way for the development of rational, science-driven combination therapeutic strategies in order to restore effective anti-tumor immunity in STK11/LKB1-deficient tumors. Citation Format: Ferdinandos Skoulidis. Inactivating STK11/LKB1 genomic alterations are a major driver of primary resistance to PD-1 axis blockade in non-squamous non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr SY42-02.

Lung cancer is one of the most common malignancies worldwide. Despite a significant amount of basic and clinical research, mortality rates remain extremely high, especially for patients affected by advanced stage disease. Recently, new molecules playing several roles in the pathogenesis, diagnosis, and, potentially, clinical management of lung cancer are under investigation, including noncoding fragments of the human genome, also known as noncoding RNAs (ncRNAs). NcRNAs are commonly divided into two categories according to their size. The first category includes small ncRNAs, such as the recently discovered miRNAs, siRNAs, and the classical cellular RNAs (ribosomal, transfer, and other RNAs). Noncoding RNAs greater than 200 nucleotides represent a further category that includes long noncoding RNAs (lncRNAs). LncRNAs have numerous biological and pathophysiological effects. Numerous studies have recently investigated their involvement in the oncogenesis and the progression of pulmonary malignancies. In this chapter, we summarize the current knowledge regarding the role of lncRNAs in the pathogenesis, diagnosis, and clinical management of non-small cell lung cancer.

Predictive Capability of PD-L1 Protein Expression for Patients With Advanced NSCLC: Any Differences Based on Histology?

43P MRTX-500: Phase II trial of sitravatinib (sitra) + nivolumab (nivo) in patients (pts) with non-squamous (NSQ) non-small cell lung cancer (NSCLC) progressing on or after prior checkpoint inhibitor (CPI) therapy

Objective:There are two new treatment options available for the treatment of adenocarcinoma histology non-small cell lung cancer (NSCLC) which offer improved benefit in terms of progression-free (PFS) and overall survival (OS) over chemotherapy. Both bevacizumab and pemetrexed when combined with chemotherapy significantly increase PFS and OS in patients with advanced NSCLC versus chemotherapy alone. The aim of this analysis was to compare the efficacy for patients with non-squamous adenocarcinoma NSCLC treated with bevacizumab, carboplatin and paclitaxel (BCP) to pemetrexed and cisplatin (PC) by using indirect comparison (ITC) methodology.Experimental design:In the absence of head-to-head trials, ITC was performed on patients with adenocarcinoma histology non-squamous NSCLC to compare the relative benefit of first-line therapies BCP vs. PC by hazard ratios (HR). Subsequently, these HRs were used in a decision-analytic Markov model with a lifelong time horizon to extrapolate the long-term effectiveness of the two treatments.Results:ITC estimated HRs for the primary endpoints in the bevacizumab study E4599 showed that BCP treatment in non-squamous adenocarcinoma NSCLC patients resulted in a BCP HR of 0.82 versus PC. The long-term predictions from the Markov model yielded a mean survival of 1.48 years (95% CI 1.34, 1.62 years) (or 17.7 months) for BCP compared with 1.29 years (95% CI 1.16, 1.42 years) (or 15.4 months) for PC.Conclusions:Based on our decision analysis, triplet BCP targeted therapy in patients with advanced non-squamous adenocarcinoma NSCLC compared with doublet PC chemotherapy results in improved expected values for overall long-term survival. Therefore, from the efficacy perspective, bevacizumab in combination with platinum-based chemotherapy can be considered as the targeted therapy of choice for patients with advanced non-squamous adenocarcinoma NSCLC.

Next-Generation Sequencing Identified a Novel Crizotinib-Sensitive PLB1-ALK Rearrangement in Lung Large-Cell Neuroendocrine Carcinoma

e18014 Background: Pemetrexed (P) is a key drug in the treatment of advanced non-squamous (N-Sq) non-small cell lung cancer (NSCLC). Although differential efficacies of P between squamous (Sq) and N-sq subtypes have been reported, it is difficult to get a clear histological diagnosis from a small biopsy sample. Therefore, a more objective, yet simple, biomarker for histology-based treatment is needed. Previously, we reported that serum Cytokeratin fragment 21-1 (CYFRA) was related to the outcome of P monotherapy. In this study, we examined whether serum CYFRA could predict the efficacy of the cisplatin-pemetrexed (CP) combination regimen as well as it did for P monotherapy. Methods: Pre-treatment serum concentrations of CYFRA, carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC) antigen, and sialyl Lewis X-I antigen (SLX) were measured in 50 N-sq NSCLC patients who were enrolled in a phase II study of C (75 mg/m2 and 500 mg/m2) against N-Sq NSCLC. Eligibility criteria consisted of histologically or cytologically confirmed recurrent or metastatic N-Sq NSCLC previously untreated with chemotherapy, ECOG performance status (PS) 0-1. The primary endpoint was response rate, which was evaluated with RECIST. The planned sample size was 50 patients. We analyzed possible associations between these NSCLC marker levels and the efficacy of the CP regimen. Results: From April 2010 to June 2011, 50 N-sq NSCLC patients (male/female, 34/16; median age 60 y (28-74 y)) were enrolled in this study. Patients’ histological characteristics were: adeno/large/not otherwise specified (NOS), 39/5/6; PS: 0/1, 31/19. In these 50 patients, elevated levels of serum CYFRA, CEA, SCC and SLX were found in 25, 32, 5 and 32 patients, respectively. CYFRA was significantly associated with progression-free survival (PFS) (median PFS: 5.53 vs. 3.29 months; p < 0.05), whereas no significant associations were observed between PFS and CEA, SCC or SLX. In addition, multivariate analysis showed that higher CYFRA and PS levels were significant factors associated with a shorter PFS. (p < 0.05) Conclusions: Serum CYFRA is related to the outcome of CP treatment; our results suggest that serum CYFRA is a promising predictive marker of CP therapy.

9539 Background: The predictive value of PD-L1 tumor proportion score (TPS) on NSCLC tumor cells as a biomarker for response to PD-(L)1 inhibitors is well established. However, its histology specific value in advanced (a) squamous (Sq) versus nonsquamous (NS) cancers remains unclear. Here, we used real world data to assess the differential value of PD-L1 TPS as a predictive biomarker for overall survival (OS) after first-line pembrolizumab (P) in patients (pts) with Sq versus NS NSCLC. Methods: Inclusion criteria for this analysis of the Flatiron Health EHR-derived de-identified database required that pts were diagnosed with aNSCLC, tested for PD-L1 TPS and received a numerical result, had no alteration in EGFR, ALK, or ROS, and received first-line, single agent P. The primary endpoint was overall survival (OS) from the first dose of P in patients with TPS ≥ 50% (H) compared to patients with TPS < 50% (L). Due to the violation of the proportional hazards assumption, a generalized gamma model of OS was used, adjusting for demographic variables and estimated median OS and their confidence intervals with the bootstrap method. The PD-L1-histology interaction was examined by comparing the differences in median OS (H vs. L) between Sq and NS patients. Results: Of 1560 pts with NSCLC treated from 1/2011 – 5/2019, 1055 had NS and 405 Sq. No meaningful differences in age, gender, or smoking history were seen between PD-L1 H and L pts with either histology. Among NS pts, H had significantly longer OS than L, with unadjusted hazard ratio (HR) of 0.71 (95% CI: 0.53 - 0.94; p = 0.018). Among Sq pts, H was not associated with longer OS than L, with unadjusted HR 0.89 (95% CI: 0.64 - 1.25; p = 0.514). Based on the generalized gamma model, PD-L1 H in Sq patients was associated with a 0.19 year improvement in median OS (95% CI: -0.22-0.49, P = 0.283), whereas PD-L1 H in the NS group was associated with a 0.70 year improvement in OS (95% CI: 0.34-1.05, P < 0.001). The median improvements between the Sq and NS patients were significantly different (P = 0.034), after adjusting for demographic variables. Conclusions: PD-L1 TPS of ≥ 50% predicted longer OS in pts with NS NSCLC treated with first-line P compared to pts whose tumors had a TPS of < 50%. However, no relationship between PD-L1 TPS and OS after first-line P was seen in patients with Sq NSCLC. These data suggest that PD-L1 may not be an appropriate predictive biomarker for checkpoint inhibitor use in NSCLC with squamous histology.

First-line Systemic Therapy for Metastatic Non-small-cell Lung Cancer – A Review

Immunotherapies are a new class of agents used in non–small-cell lung cancer (NSCLC) that require refinement of the optimal sequence and identification

e18047 Background: In NSCLC patients with adenocarcinoma or large cell carcinoma, symptomatic BM frequently occur following treatment. Considering the particular activity of P in nonsquamous NSCLC, we retrospectively analyzed two large randomized trials to determine the investigators' reported pattern of symptomatic relapse in the brain. Methods: Two large, phase III studies of P in advanced NSCLC were included in this retrospective analysis. One study (N = 1725) tested cisplatin plus P versus cisplatin plus gemcitabine in chemotherapy-naive patients with advanced NSCLC (Scagliotti JCO 2008) and the other (N = 571) tested P versus docetaxel in previously treated patients (Hanna JCO 2004). Patients (pts) with known BM at study entry were excluded. Each study was analyzed separately to determine the rate of BM reported as the only site of progressive disease (PD) by treatment group and histology. Logistic regression was used to obtain an odds ratio (OR) for the treatment effect on BM while controlling for potential confounding factors. Results: Overall, 71.5% of pts in P-containing arms (819 of 1145) and 68.2% of pts in non-P-containing arms (785 of 1151) experienced PD. BM relapse rates by treatment arm, study, and histologic subgroup are summarized below (Table). Conclusions: Nonsquamous advanced NSCLC pts treated with P either in first-line or second-line in phase III studies may have reduced risk of developing BM as the first site of PD. This retrospective analysis is limited due to the lack of prospectively performed, periodic brain CT scans; therefore this analysis reflects symptomatic BM only. Nonetheless, these findings may imply a possible positive effect on the control of BM with P in the nonsquamous population. BM relapse rates P-containing arms Non-P-containing arms Fisher's exact P value Overall (both studies) 3.2% (26 of 819) 6.6% (52 of 785) 0.002 Scagliotti study only 3.6% (22 of 621) 6.5% (39 of 604) 0.025 Hanna study only 2.0% (4 of 198) 7.2% (13 of 181) 0.023 All nonsquamous pts (both studies) 3.0% (18 of 602) 7.3% (42 of 577) <0.001 All squamous pts (both studies) 3.7% (8 of 217) 4.8% (10 of 208) 0.635 OR for treatment effect of P (95% confidence intervals) 0.494 (0.32, 0.75) Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Lilly Lilly

Immune checkpoint inhibitors have dramatically reshaped the landscape of non–small-cell lung cancer (NSCLC). In particular, monoclonal antibodies targeting the programmed death-1 (PD-1)/PD ligand 1 (PD-L1) pathway have emerged as powerful new therapeutic tools. In phase I studies, these agents demonstrated promising antitumor activity and durable clinical responses in a subset of patients with NSCLC. On the basis of these early efficacy signals, a series of randomized phase II and III studies were launched to evaluate the activity of PD-1/PD-L1 inhibitors in the second-line setting and beyond in NSCLC. In the CheckMate 017 and 057 studies, for example, the PD-1 inhibitor nivolumab produced significant improvements in overall survival (OS) compared with docetaxel in patients with previously treated, squamous and nonsquamous NSCLC, respectively. Similarly, the PD-1 inhibitor pembrolizumab improved OS compared with docetaxel among patients with previously treated NSCLC whose tumors expressed PD-L1. Together, these studies helped establish PD-1 pathway blockade as a new standard of care for patients with advanced NSCLC who experience progression on or after platinum-based chemotherapy. Recently, the activity and improved tolerability of PD-1/PD-L1 inhibitors in NSCLC have sparked a growing interest in moving these agents to the front-line setting. Currently, the standard of care for management of newly diagnosed patients without targetable oncogenic driver mutations (eg, EGFR, ALK) is platinum-based doublet chemotherapy, which is generally associated with a median progressionfree survival (PFS) of 4 to 6months andmedianOS of 8 to 10months. More recently, maintenance pemetrexed and the addition of monoclonal antibodies directed against vascular endothelial growth factor and epidermal growth factor receptor have resulted in additional, modest improvements in OS, yet long-term outcomes remain poor, underscoring the need for alternative therapeutic approaches. In the two articles accompanying this editorial, we are presented with data from two separate cohorts of the multiarm, phase IB CheckMate 012 study. Each explores a different approach to PD-1 inhibition in patients with treatment-naive NSCLC. First, Gettinger et al report findings from 52 patients with advanced NSCLC treated with first-line nivolumab monotherapy. Importantly, PD-L1 testing was not used to prospectively select patients for study entry, but mandatory pretreatment biopsies were required to evaluate PD-L1 expression retrospectively. Confirmed responses were observed in 23% of patients, including complete responses in four patients (8%). Median PFS on nivolumab was 3.6 months, but the median duration of response was not reached (range, 4.2 to 25.81months). Thus, as with other studies of PD-1/ PD-L1 inhibitors, there was a suggestion of durable clinical responses. Indeed, the median OS in this patient population was noteworthy at 19.4 months. Although the results by Gettinger et al are intriguing, it is noteworthy that the response rate to first-line nivolumab was not too dissimilar from those observed in CheckMate 017 and 057. A key issue, however, is whether this degree of activity will be sufficient to beat platinum-based chemotherapy in randomized trials. In second-line studies (CheckMate 017 and 057), the control arms received single-agent docetaxel, which set a relatively low bar to surpass (historical overall response rate, approximately 7%). By contrast, in the first-line setting, PD-1/PD-L1 inhibitors will need to overtake platinum-based doublet chemotherapy, which has been associated withmuch higher ORRs (25% to 35%). For PD-1/ PD-L1 inhibitors to succeed in this setting, a biomarker enrichment strategy may be necessary. To date, such efforts have centered on assessments of PD-L1 expression. For instance, in the KEYNOTE 001 study, pembrolizumab was associated with an ORR of 24.8% among treatment-naive patients, but the response rate increased to 50% among treatment-naive patients who were PD-L1 positive (proportion score $ 50). In part on the basis of these observations, two randomized phase III studies, CheckMate 026 and KEYNOTE 024, have been launched in PD-L1–positive patients comparing platinum-based chemotherapy versus nivolumab or pembrolizumab, respectively. Both studies have completed accrual, but results are not yet available. In the second article accompanying this editorial, Rizvi et al report a separate first-line cohort from CheckMate 012 that consisted of 56 treatment-naive patients with NSCLC who were treated with nivolumab in combination with three different platinum-based chemotherapy doublets. The authors used a dose de-escalation design, assigning participants to one of four cohorts ranging in size from 12 to 15 patients. Of note, in contrast to the currently approved nivolumab dosing regimen (3 mg/kg every 2 weeks), nivolumab was administered once every 3 weeks in this study (5 to 10mg/kg based on cohort). After completing four cycles of therapy, patients received maintenance nivolumab once every 3 weeks. Overall, no dose-limiting toxicities were observed across study arms, but 14% of patients required discontinuation as

P2.01-081 CDCA3 is a Novel Prognostic Cell Cycle Protein and Target for Therapy in Non-Small Cell Lung Cancer

AJ-2 - Development of Nationwide Genomic Screening Project (LC-SCRUM-Japan) for the Establishment of Cancer Precision Medicine

Although pathologic stage I (pStage I) non–small cell lung cancer (NSCLC) has a good prognosis, some patients experience disease recurrence. Identification of prognostic markers for pStage I NSCLC may facilitate personalized perioperative treatment by expanding the candidates for adjuvant treatment. Patients with NSCLC with ground-glass opacity have excellent survival outcomes. Therefore, in this study, we explored prognostic biomarkers in pure solid nonsquamous NSCLC. We focused on nonsquamous NSCLC because the gene expression status is distinct from that of squamous cell carcinomas. RNA sequencing was performed on frozen tumor specimens from 33 patients with nonsquamous NSCLC with disease recurrence (recurrence group) and 33 counterparts (control group) extracted from patients without disease recurrence using propensity score matching (cohort 1). The candidate genes were further refined using an independent real-world cohort 2a (N = 125) and validated in The Cancer Genome Atlas cohort. Through the analysis of cohort 1 and cohort 2a, we found that low expression of six genes (BMP6, KCNK3, NFASC, OLFM1, PEG3, and TNXB) was associated with disease recurrence. The prognostic impact of the six genes was confirmed using The Cancer Genome Atlas lung adenocarcinoma database. Multivariable proportional hazard analysis using the cohort 2a dataset revealed that the combination of BMP6 and OLFM1 status predicted recurrence-free survival. In conclusion, we found that low BMP6/OLFM1 gene status is a potential biomarker to identify patients with high-risk pStage I pure solid nonsquamous NSCLC after pulmonary resection.Significance:The identification of subgroups with a high risk of disease recurrence among patients with NSCLC with pStage I is an important clinical issue. We explored genetic factors in patients with pStage I NSCLC with a high-risk clinical feature and identified low expression of OLFM1 and BMP6 genes as candidate biomarkers. Clinical application of these biomarkers, together with others, will open an opportunity to administer adequate adjuvant treatment for these high-risk patients.