Tumor-initiating cells (TICs) preferentially reside in poorly vascularized, nutrient-stressed tumor regions, yet how they adapt to glucose limitation is unclear. We show that lung TICs, unlike bulk tumor cells, can switch from glucose to ketone utilization under glucose deprivation. Ex vivo ketone supplementation or a prolonged ketogenic diet supports TIC growth and tumor-initiating capacity. Integrated metabolomics, genomics, and flux analyses reveal that ketones fuel ketolysis, fatty acid synthesis, and de novo lipogenesis. Paradoxically, ketogenic diet intervention creates metabolic vulnerabilities in TICs, sensitizing them toward inhibition of the ketone transporter monocarboxylate transporter 1 (MCT1), regulated by its chaperone protein CD147, as well as toward pharmacological blockade of fatty acid synthase (FASN). Loss of CD147 ablates TICs under glucose limitation conditions in vitro and in vivo. These findings uncover a nutrient-responsive metabolic switch in lung TICs and provide mechanistic insight into how dietary manipulation can influence cancer progression and enhance the efficacy of targeted therapies.

Abstract Non-small cell lung cancers (NSCLCs) in non-smokers are mostly driven by mutations in the oncogenes EGFR, ERBB2, and MET, and fusions involving ALK and RET. We term these “non-smoking-related oncogenes” (NSROs). NSRO-driven tumors account for approximately half of NSCLCs in East Asia, and, alarmingly, their age-adjusted incidence is increasing for unknown reasons. In addition to occurring in non-smokers, NSRO-driven tumors also occur in smokers. However, the clonal architecture and genomic landscape of these tumors remain largely unexplored. Here, we investigated genomic and transcriptomic alterations in 173 tumor sectors from 48 patients with NSRO-driven or typical-smoking NSCLCs. Overall, NSRO-driven NSCLCs in smokers and non-smokers had similar genomic landscapes and clonal architectures that were distinct from those in typical-smoking NSCLCs. Surprisingly, even in patients with prominent smoking histories, the mutational signature caused by tobacco smoking was essentially absent in NSRO-driven NSCLCs. We confirmed this unexpected finding in two large NSCLC data sets from other geographic regions. However, we observed differences in the tumor transcriptomes of NSRO-driven NSCLCs in smokers and non-smokers, with tumors in smokers displaying higher transcriptomic activities related to regulation of the cell cycle. This suggested that smoking does have an impact on tumor phenotype in NSCRO-driven NSCLC, likely through non-genetic mechanisms. We concluded that NSRO-driven NSCLCs, whether in non-smokers or smokers, constitute an important disease entity that is very different from typical-smoking NSCLC. Citation Format: Chen-Yang Huang, Nanhai Jiang, Meixin Shen, Gillianne Lai, Aaron C. Tan, Amit Jain, Stephanie P. Saw, Mei-Kim Ang, Quan Sing Ng, Darren Wan-Teck Lim, Ravindran Kanesvaran, Eng-Huat Tan, Wan Ling Tan, Boon-Hean Ong, Kevin L. Chua, Devanand Anantham, Angela Takano, Tony KH Lim, Wai Leong Tam, Ngak Leng Sim, Anders J. Skanderup, Daniel S.W. Tan, Steven G. Rozen. Dearth of smoking-induced mutations in oncogene-driven NSCLCs despite smoking exposure [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1748.

Background: In early-stage non-small cell lung cancer (NSCLC), recurrence is frequently observed. Circulating tumor DNA (ctDNA) has emerged as a noninvasive tool to risk stratify patients for recurrence after curative intent therapy. This study aimed to risk stratify patients with early-stage NSCLC via a personalized, tumor-informed multiplex polymerase chain reaction (mPCR) next-generation sequencing assay. Methods: This retrospective cohort study included patients with stage I-III NSCLC. Recruited patients received standard-of-care management (surgical resection with or without adjuvant chemotherapy, followed by surveillance). Whole-exome sequencing of NSCLC resected tissue and matched germline DNA was used to design patient-specific mPCR assays (Signatera, Natera, Inc) to track up to 16 single-nucleotide variants in plasma samples. Results: The overall cohort with analyzed plasma samples consisted of 57 patients. Stage distribution was 68% for stage I and 16% each for stages II and III. Presurgery (i.e., at baseline), ctDNA was detected in 15 of 57 patients (26%). ctDNA detection presurgery was significantly associated with shorter recurrence-free survival (RFS; hazard ratio [HR], 3.54; 95% confidence interval [CI], 1.00-12.62; p = .009). In the postsurgery setting, ctDNA was detected in seven patients, of whom 100% experienced radiological recurrence. ctDNA positivity preceded radiological findings by a median lead time of 2.8 months (range, 0-12.9 months). Longitudinally, ctDNA detection at any time point was associated with shorter RFS (HR, 16.1; 95% CI, 1.63-158.9; p < .0001). Conclusions: ctDNA detection before surgical resection was strongly associated with a high risk of relapse in early-stage NSCLC in a large unique Asian cohort. Prospective studies are needed to assess the clinical utility of ctDNA status in this setting.

Abstract Non–small cell lung cancers (NSCLC) in nonsmokers are mostly driven by mutations in the oncogenes EGFR, ERBB2, and MET and fusions involving ALK and RET. In addition to occurring in nonsmokers, alterations in these “nonsmoking-related oncogenes” (NSRO) also occur in smokers. To better understand the clonal architecture and genomic landscape of NSRO-driven tumors in smokers compared with typical-smoking NSCLCs, we investigated genomic and transcriptomic alterations in 173 tumor sectors from 48 NSCLC patients. NSRO-driven NSCLCs in smokers and nonsmokers had similar genomic landscapes. Surprisingly, even in patients with prominent smoking histories, the mutational signature caused by tobacco smoking was essentially absent in NSRO-driven NSCLCs, which was confirmed in two large NSCLC data sets from other geographic regions. However, NSRO-driven NSCLCs in smokers had higher transcriptomic activities related to the regulation of the cell cycle. These findings suggest that, whereas the genomic landscape is similar between NSRO-driven NSCLC in smokers and nonsmokers, smoking still affects the tumor phenotype independently of genomic alterations. Significance: Non-small cell lung cancers driven by nonsmoking-related oncogenes do not harbor genomic scars caused by smoking regardless of smoking history, indicating that the impact of smoking on these tumors is mainly nongenomic.

Background: Osimertinib is a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) approved for use in EGFR-mutant lung cancer. We examined its performance in the second/ subsequent line after resistance to first- and second-generation (1/2G) EGFR-TKI. Methods: We reviewed electronic records of 202 patients who received osimertinib from July 2015 to January 2019 in the second/subsequent line after progression on prior EGFR-TKI. Of these, complete data from 193 patients were available. Clinical data including patient characteristics, primary EGFR mutation, T790M mutation status, presence of baseline brain metastases (BM), first-line EGFR-TKI use, and survival outcomes were extracted, and results retrospectively analyzed. Results: Of 193 evaluable patients, 151 (78.2%) were T790M+ (T790M positive) with 96 (49.2%) tissue confirmed; 52% of patients received osimertinib in the second line setting. After median follow up of 37 months, median progression free survival (PFS) of the entire cohort was 10.3 [95% confidence interval (CI): 8.64-11.50] months and median overall survival (OS) was 20 (95% CI: 15.61-23.13) months. Overall response rate (ORR) to osimertinib was 43% (95% CI: 35.9-50.3%); 48.3% in T790M+ vs. 20% in T790M- (T790M negative) patients. OS in T790M+ patients was 22.6 vs. 7.9 months in T790M- patients (HR 0.43, P=0.001), and PFS was 11.2 vs. 3.1 months respectively (HR 0.52, P=0.01). Tumour T790M+ was significantly associated with longer PFS (P=0.007) and OS (P=0.01) compared to tumour T790M- patients, however this association was not seen with plasma T790M+. Of the 22 patients with paired tumor/plasma T790M testing, response rate (RR) to osimertinib was 30% for those plasma T790M+/tumour T790M-, compared to 63% and 67% for those who were plasma T790M+/tumour T790M+ and plasma T790M-/ tumour T790M+, respectively. By multivariable analysis (MVA), Eastern Cooperative Oncology Group (ECOG) performance status >= 2 was associated with shorter OS ( HR 2.53, P < 0.001) and PFS ( HR 2.10, P < 0.001), whereas presence of T790M+ was associated with longer OS (HR 0.50, P=0.008) and PFS (HR 0.57, P=0.027). Conclusions: This cohort demonstrated the efficacy of osimertinib in second line/beyond for EGFR+ predictive of osimertinib efficacy compared to plasma, highlighting potential T790M heterogeneity and the

Neurological interventions have taken on a significant role in interventional radiology (IR) practice. Indications fall under three main categories: (1) intraprocedural pain management, (2) cancer pain palliation, and (3) chronic non-cancer pain control. Short-term regional anaesthesia can be achieved with local anaesthetics, while longer-term pain control can be attained with radiofrequency neuromodulation (pulsed or otherwise) or thermal/chemical neurolysis. This review article summarises the therapeutic options, applications, and tech-niques of commonly used peripheral nerve and plexus interventions in IR.(c) 2022 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Supplementary Data from Integrative Profiling of T790M-Negative EGFR-Mutated NSCLC Reveals Pervasive Lineage Transition and Therapeutic Opportunities

Clearance of plasma epidermal growth factor receptor mutations (pEGFR) post-tyrosine kinase inhibitors (TKI) correlates with improved survival. While droplet digital polymerase chain reaction (ddPCR) and plasma next generation sequencing (NGS) are widely used for diagnosis, head-to-head comparisons are scarce. We sought to compare the performance of ddPCR and Oncomine Pan-Cancer Cell-Free Assay®, a 52-gene NGS panel, in detecting clearance of pEGFR as a predictor of response to EGFR TKI.

EGFR exon 20 insertion (ex20ins) mutated NSCLC is associated with poor response to targeted therapies with activity against 'classical' EGFR mutations. Recently, novel therapies (amivantamab and mobocertinib) have demonstrated modest clinical activity and received regulatory approval. However, there remain limited in-depth studies on the clinicopathologic and genomic characterization of EGFR ex20ins mutated NSCLC in Asia.

Introduction: Although immune checkpoint inhibitors (ICIs) have dramatically improved outcomes for nononcogene-addicted NSCLC, monotherapy with programmed cell death protein-1 (PD1) inhibition has been associated with low efficacy in the EGFR-mutant setting. Given the potential for synergism with combination checkpoint blockade, we designed a trial to test the activity of combination nivolumab (N)-ipilimumab (NI) in EGFRmutant NSCLC. Methods: This is a randomized phase 2 study (NCT03091491) of N versus NI combination in EGFR tyrosine kinase inhibitor (TKI)-resistant NSCLC, with crossover permitted on disease progression. The primary end point was the objective response rate, and the secondary end points included progression-free survival, overall survival, and safety of ICI after EGFR TKI. Results: Recruitment ceased owing to futility after 31 of 184 planned patients were treated. A total of 15 patients received N and 16 received NI combination. There were 16 patients (51.6%) who had programmed death-ligand (PDL1) 1 greater than or equal to 1%, and 15 (45.2%) harbored EGFR T790M. Five patients derived clinical benefits from ICI with one objective response (objective response rate 3.2%), and median progression-free survival was 1.22 months (95% confidence interval: 1.15-1.35) for the overall cohort. None of the four patients who crossed over achieved salvage response by NI. PDL1 and tumor mutational burden (TMB) were not able to predict ICI response. Rates of all grade immune-related adverse events were similar (80% versus 75%), with only two grade 3 events. Conclusions: Immune checkpoint inhibition is ineffective in EGFR TKI-resistant NSCLC. Whereas a small subgroup of EGFR-mutant NSCLC may be immunogenic and responsive to ICI, better biomarkers are needed to select appropriate patients.(c) 2022 The Authors. Published by Elsevier Inc. on behalf of the International Association for the Study of Lung Cancer. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Objectives: To analyze the efficacy and safety of lorlatinib in Asian and non-Asian patients with pretreated anaplastic lymphoma kinase (ALK)-positive, advanced non-small cell lung cancer (NSCLC) from a phase 1/2 study.Materials and methods: In this ongoing phase 2 part of the trial, patients with ALK- or ROS1-positive, advanced NSCLC enrolled into six expansion cohorts (EXP1-6), based on ALK and ROS1 status and previous therapy, and received lorlatinib 100 mg once daily. The primary endpoint was objective tumor response and intracranial response. Post hoc analyses of activity were conducted in Asian and non-Asian (based on race) ALK-positive patients who received either previous crizotinib with or without chemotherapy (EXP2-3A) or at least one second generation ALK tyrosine kinase inhibitor with any number of chemotherapy regimens (EXP3B-5). Analysis of safety (adverse events [AEs]) was in the phase 1 and 2 study population who started lorlatinib 100 mg once daily.Results: 17 Asian patients were enrolled in EXP2-3A and 53 in EXP3B-5; 33 non-Asian patients were enrolled in EXP2-3A and 73 in EXP3B-5. Objective response rates in the Asian and non-Asian subgroups were 82.4% (95% confidence interval [CI]: 56.6-96.2) and 63.6% (95% CI: 45.1-79.6) in EXP2-3A, and 47.2% (95% CI: 33.3-61.4) and 30.1% (95% CI: 19.9-42.0) in EXP3B-5, and median progression-free survival was 13.6 and 12.5 months (EXP2-3A) and 6.9 and 5.5 months (EXP3B-5). Lorlatinib exhibited antitumor activity across ALK resistance mutations, while no differences according to the EML4-ALK variant could be detected. The most common treatment-related AEs were hypercholesterolemia, hypertriglyceridemia, edema, and peripheral neuropathy in both Asian and non-Asian subgroups.Conclusion: Lorlatinib showed substantial overall and intracranial activity in pretreated patients with ALK-pos-itive NSCLC in both Asian and non-Asian patients. AE profiles were similar between Asian and non-Asian pa-tients. ClinicalTrials.gov NCT01970865.

HER2-mutated (HER2-M+) non-small cell lung cancer (NSCLC) represents a distinct molecular subtype with expanding therapeutic options including HER2 antibody-based therapies and tyrosine kinase inhibitors. We describe the molecular epidemiology and genomic features of HER2-M+ NSCLC in the setting of an Asian tertiary cancer centre.

Background: Early detection of recurrence and monitoring of MRD post-surgery is critical for clinical decision-making to tailor adjuvant therapy. In early-stage NSCLC, circulating tumor DNA (ctDNA) detection is especially challenging, requiring highly sensitive and specific assays. Therefore, we used a WGS approach (MRDetect) for ultra-sensitive ctDNA detection in NSCLC patients (pts) undergoing curative surgery. Methods: We conducted a pilot study to evaluate the MRDetect approach in serial plasma samples (including pre-surgery, post-surgery and follow-up [f/u] timepoints) from resected stage IB-IIIA NSCLC pts. Pts underwent routine surveillance by computed tomography scans. ctDNA was extracted from ~1mL plasma. MRDetect uses WGS by a tumor-informed approach (sequencing coverage 40x for tumor, 20x for plasma DNA) combined with AI-based error suppression models (trained and calibrated with a non-cancer cohort, n=17) to increase the signal to noise ratio for precise ctDNA detection, and improve the accuracy of readouts especially for low tumor burden scenarios. The assay reports the detection and quantification of ctDNA burden in blood with a prognostic value for risk of recurrence. The ability of the assay to predict recurrence from a single sample, taken at the clinical landmark point (median 1.6 mths post-surgery, range 0.1-6.5) was evaluated. Results: Overall, 52 NSCLC pts were enrolled (n=88 plasma samples) with median clinical f/u of 32.6 mths (range 3.1-98.6). There were 43 pts with post-surgery landmark samples, with median age 62 years, 70% were male, 79% were adenocarcinoma and 49% were EGFR mutated. 26% were stage IB and 37% each were stage II and III. There were 15/18 (sensitivity 83%) pts with confirmed radiological recurrence in which MRDetect was positive, including 6/7 (86%) EGFR mutated pts. The median RFS in MRDetect positive pts was 15.2 mths (range 3.7-33.4). Among 25 pts with no recurrence (median f/u 25.6 mths), MRDetect reported 4 pts to be MRD positive (specificity 84%). These results were consistent between EGFR mutated (sensitivity 86%, specificity 86%) and wildtype pts (sensitivity 82%, specificity 82%). For longitudinal samples (n=17 pts), negative ctDNA was associated with absence of recurrence in 14/15 pts (specificity 93%). At the AACR meeting, results from a planned larger validation study will be presented. Conclusion: Using a robust WGS implemented AI-based computational platform (MRDetect), we demonstrate high sensitivity and specificity detection of MRD in both EGFR mutated and wildtype NSCLC. With an increasing number of therapeutic options in the adjuvant setting for NSCLC, an ultra-sensitive MRD assay has the potential to facilitate personalized clinical decision-making for tailoring both the need and choice of adjuvant therapies. Citation Format: Aaron C. Tan, Stephanie P. Saw, Gillianne G. Lai, Kevin L. Chua, Angela Takano, Boon-Hean Ong, Tina P. Koh, Amit Jain, Wan Ling Tan, Quan Sing Ng, Ravindran Kanesvaran, Tanujaa Rajasekaran, Sunil Deochand, Dillon Maloney, Danielle Afterman, Tomer Lauterman, Noah Friedman, Imane Bourzgui, Nidhi Ramaraj, Zohar Donenhirsh, Ronel Veksler, Jonathan Rosenfeld, Ravi Kandasamy, Iman Tavassoly, Boris Oklander, Asaf Zviran, Wan-Teck Lim, Eng-Huat Tan, Anders J. Skanderup, Mei-Kim Ang, Daniel S. Tan. Ultra-sensitive detection of minimal residual disease (MRD) through whole genome sequencing (WGS) using an AI-based error suppression model in resected early-stage non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5114.

AIM:To determine the prognostic value of programmed death-ligand 1 (PD-L1) score in early-stage epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), contrasted against EGFR-wildtype NSCLC. METHODS:Consecutive patients with Stage IA-IIIA NSCLC diagnosed 1st January 2010-31st December 2019 at National Cancer Centre Singapore with evaluable EGFR and PD-L1 status were included. Co-primary end-points were 2-year disease-free survival (DFS) and 5-year overall survival (OS) by Kaplan-Meier method. RESULTS:455 patients were included (267 EGFR-mutated, EGFR-M+; 188 EGFR-wildtype, wt). Median age at diagnosis was 65 years, 52.3% (238/455) of patients were males, 62.9% (286/455) of patients were never-smokers and 92.5% (421/455) of patients had R0 resection. Stage IA comprised 42.4% (193/455) of patients, Stage IB comprised 23.1% (105/455) of patients, Stage IIA comprised 10.8% of patients (49/455), Stage IIB comprised 5.1% of patients (23/455) and Stage IIIA comprised 18.7% (85/455) of patients. Among EGFR-M+, 45.3% (121/267) were Ex19del and 41.9% (112/267) were L858R. PD-L1 ≥1% among EGFR-M+ and EGFR-wt was 45.3% (121/267) and 54.8% (103/188) respectively (p = 0.047). At median follow-up of 47 months, 178 patients had relapsed. Among EGFR-M+, 2-year DFS comparing PD-L1 <1% and PD-L1 ≥1% was 78.1% and 67.6% (p = 0.007) while 5-year OS was 59.5% and 42.8% (p = 0.001), respectively. Controlling for age, gender, lymphovascular invasion, adjuvant therapy and resection margin status, PD-L1 ≥1% (hazard ratio, HR 2.18, 95% CI 1.04-4.54, p = 0.038), stage IIB (HR 7.78, 95% CI 1.72-35.27, p = 0.008) and stage IIIA (HR 4.45, 95% CI 1.44-13.80, p = 0.01) emerged as independent predictors of inferior OS on multivariable analysis. In exploratory analysis, genomic analysis of 81 EGFR-M+ tumours was performed. PD-L1 ≥1% tumours had significantly higher rates of TP53 mutations (36.1% versus 15.6%, p = 0.04), with predominantly missense mutations. CONCLUSION:PD-L1 ≥1% is an independent predictor of worse OS among early-stage EGFR-mutated NSCLC and is associated with inferior DFS regardless of EGFR status. PD-L1 score as a risk stratification factor should be evaluated in prospective adjuvant studies among EGFR-mutated NSCLC.

In early stage non-small cell lung cancer (NSCLC), recurrence is frequently observed and overall long-term survival remains poor. Circulating tumor DNA (ctDNA) has emerged as an effective non-invasive tool to detect/monitor minimal/molecular residual disease (MRD) and potentially guide systemic therapies to improve outcomes.

The ADAURA study showed significant reduction in risk of disease recurrence/death with adjuvant osimertinib for Stage IB–IIIA resected EGFR-mutated NSCLC. However, due to early unblinding of the study coupled with paucity of data on patterns of relapse and absence of long-term survival data, the cost:benefit ratio of adjuvant osimertinib remains uncertain. We sought to determine molecular and clinical features that impact outcomes in early stage EGFR-mutated NSCLC.

Invasive mucinous adenocarcinoma (IMA) is an uncommon adenocarcinoma variant defined by goblet or columnar cells containing intracytoplasmic mucin and extensive extracellular mucin. Historically, IMAs have been associated with a poorer prognosis. However emerging evidence indicates a majority harbour potentially actionable driver oncogenes and IMA may be associated with downregulation of lung lineage-specifying transcription factor NKX2-1/TTF-1 resulting in a mid/hindgut phenotype. Morphologic features of IMA have also not been well characterised.

RET rearrangements are emerging as a targetable oncogenic fusion driver in 1-2% of NSCLC patients. Promising efficacy of novel selective RET tyrosine kinase inhibitors (TKI) such as selpercatinib and praseltinib have been demonstrated in early phase trials. However, the natural history of disease and the activity of different classes of systemic therapy remains to be defined. Furthermore, routine molecular testing for RET is not yet standard of care and the optimal method of testing is unclear. We present a comparative analysis of molecular profiling with FISH or NGS and correlations with clinical and treatment outcomes.