Abstract Background: Although PD-1 axis inhibitors have improved outcomes in patients with mNSCLC, only a subset of patients derives long-term benefit. Most studies assessing determinants of sensitivity have relied on short-term endpoints such as response, potentially overlooking biological features underlying durable tumor control. We hypothesized that patients achieving prolonged response after PD-1 axis blockade exhibit distinct tumor microenvironment (TME) features compared with those with primary resistance or limited response. Methods: We assembled a retrospective cohort of bulk whole-transcriptome data from 342 pretreatment tumor samples from patients with mNSCLC treated with PD-1 axis blockade alone or in combination with anti-CTLA-4 therapy from Yale (n=31), Stand Up To Cancer (n=73), and Samsung Medical Center (n=278). Patients were classified as having primary progression (PP; PFS <3 mo; n=200), non-exceptional response (NER; PFS 6-36 mo; n=116), and prolonged survival (PS; PFS >36 mo; n=26). After batch correction, differential expression (limma) and CIBERSORT were used to identify genes and immune cells associated with PS. Single-cell RNA sequencing from a publicly-available lung cancer immune cell atlas (n=234) was used to refine immune cell signatures and assess their association with outcomes via ssGSEA. Spatial proteomics (Phenocycler-Fusion) performed on baseline samples from patients treated with PD-1 axis blockade (n=55; PP=21, NER=26, PS=8) at Yale and the University of Queensland was used for validation. Results: Tumors from PP, NER, and PS demonstrated a stepwise increase in HLA class I antigen-presentation machinery (APM) transcripts (PSMB9, ERAP2), memory T-cell markers (CXCR6), and CD8+ T-cell infiltration. PD-L1 expression was markedly higher in NER than PP, but similar between NER and PS. The most significantly enriched genes in PS relative to NER were macrophage-related, with higher absolute M1 (Cliff’s δ=0.34, p=0.007) and M2 (δ=0.29, p=0.023) tumor-associated macrophage (TAM) scores. This difference was not observed between NER and PP. Four percent of patients with low (≤ median) calculated CD8+ T-cell and TAM levels were PS, compared with 15% of those with high CD8+/TAM levels (odds ratio=4.5, p=0.0083). Single-cell analysis identified 15 TAM subsets, several enriched in PS but none in PP. Spatial proteomics confirmed an increase in the proportion of stromal TAMs in PS (PS vs NER: δ=0.62, p=0.0079; PS vs PP: δ=0.58, p=0.016) and revealed a stepwise decrease in the proportion SMA+ fibroblasts across clinical benefit groups. Conclusion: Prolonged survival after PD-1 blockade in mNSCLC is associated with distinct TME features including increased expression of APM components, and increased CD8 T-cells and TAMs. These insights may inform the development of predictive biomarkers and novel therapeutic strategies. Citation Format: Daniel Boiarsky, Thazin Nwe Aung, Anna Wurtz, Jianlei Gu, Benjamin Y. Lu, David L. Rimm, Arutha Kulasinghe, Katerina A. Politi, Scott Gettinger, Kurt Alex Schalper. Intratumoral effector T-cells and macrophages underlie prolonged survival after PD-1 axis blockade in metastatic non-small cell lung cancer (mNSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7742.

T-cell phenotypic marker comparison between responders and non-responders

IOV-COM-202 patient treatment schema. CY, cyclophosphamide; EOA, end of assessment; EOS, end of study; EOT, end of treatment; FLU, fludarabine; GMP, Good Manufacturing Practice; NMA-LD, nonmyeloablative lymphodepletion; TIL, tumor-infiltrating lymphocytes.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Non-Small Cell Lung Cancer (NSCLC) provide recommendations for the treatment of patients with NSCLC, including diagnosis, primary disease management, surveillance, and subsequent treatment. The panel has updated the list of recommended targeted therapies based on recent FDA approvals and clinical data. This selection from the NCCN Guidelines for NSCLC focuses on treatment recommendations for advanced or metastatic NSCLC with actionable biomarkers.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Non-Small Cell Lung Cancer (NSCLC) provide recommendations for the treatment of patients with NSCLC, including diagnosis, primary disease management, surveillance, and subsequent treatment. The panel has updated the list of recommended targeted therapies based on recent FDA approvals and clinical data. This selection from the NCCN Guidelines for NSCLC focuses on treatment recommendations for advanced or metastatic NSCLC with actionable biomarkers.

Mesothelioma is a rare cancer that originates from the mesothelial surfaces of certain sites within the body. Pleural mesothelioma is the most common type and represents approximately 85% of mesotheliomas. The NCCN Guidelines for Mesothelioma: Pleural provide recommendations for evaluation and treatment in patients with pleural mesothelioma. The NCCN Guidelines will continue to be updated annually based on available clinical evidence and panel consensus.

Tumor resection adverse events reported as related to surgery in the tumor tissue procurement set

CONSORT diagram for Cohort 3B of the IOV-COM-202 study

The NCCN Guidelines for Non-Small Cell Lung Cancer (NSCLC) provide recommendations for the treatment of NSCLC. These NCCN Guidelines Insights discuss recent updates to the NCCN Guidelines, with a focus on systemic therapy options for the treatment of patients with nonmetastatic NSCLC and the corresponding molecular testing considerations.

Background With nearly one-third of patients with advanced non-small cell lung cancer (NSCLC) and PD-L1 Tumor Proportion Score≥50% surviving beyond 5 years following first-line pembrolizumab, long-term outcomes challenge traditional paradigms of cancer prognostication. The emergence of non-cancer-related factors and time-dependent trends underscores the need for advanced analytical frameworks to unravel their complex interplay.Methods We analyzed the Pembro-real 5Y registry, a global real-world dataset of 1050 patients treated across 61 institutions in 14 countries with a long-term follow-up and a large panel of baseline variables. Two complementary approaches were employed: ridge regression, chosen for its ability to address multicollinearity while retaining interpretability, and not another imputation method (NAIM), a transformer-based artificial intelligence model designed to handle missing data without imputation. Endpoints included risk of death at 6, 12, 24, 60 months and 5-year survival.Results The ridge regression model achieved a c-statistic of 0.66 (95% CI: 0.59 to 0.72) for the risk of death and an area under the curve (AUC) of 0.72 (95% CI: 0.65 to 0.78) for 5-year survival, identifying Eastern Cooperative Oncology Group Performance Status (ECOG-PS)≥2, increasing age, and metastatic burden as primary risk factors. However, wide CIs for some predictors highlighted statistical instability. NAIM demonstrated robust handling of missing data, with a c-index of 62.98±2.11 for risk of death and an AUC of 60.52±3.71 for 5-year survival. The comprehensive SHapley Additive exPlanations analysis revealed dynamic, time-dependent patterns, with early mortality dominated by acute factors (eg, ECOG-PS, steroids) and long-term outcomes increasingly influenced by systemic health markers (eg, absence of hypertension, increasing body mass index). Unexpected insights included the protective role of dyslipidemia (but not statins) and the nuanced impact of smoking status, reflecting evolving disease dynamics and host-tumor interplay.Conclusions Our integrative framework illuminates the complexity of long-term outcomes in patients with NSCLC treated with pembrolizumab, uncovering dynamic, non-linear prognostication trends. This analysis provides insights into patient trajectories, emphasizing the need for holistic, long-term management strategies.

BACKGROUND:Brigatinib, a selective ALK inhibitor, demonstrated preclinical activity against a range of crizotinib-resistant ALK alterations in NSCLC. We examined associations between brigatinib efficacy and tumor- and plasma-detected driver mutations in crizotinib-resistant ALK fusion-positive NSCLC. PATIENTS AND METHODS:Tumor tissue and plasma circulating tumor DNA (ctDNA) from patients with crizotinib-exposed ALK-positive NSCLC receiving brigatinib in phase 1/2 and phase 2 ALTA trials were analyzed by next-generation sequencing. Objective response rate (ORR) and progression-free survival (PFS) were assessed by mutation status. RESULTS:Ninety-three patients were molecularly profiled at baseline (tumor, 26; ctDNA, 59; 8 with both). Patients received a range of doses, most commonly 90 mg QD. For patients with baseline tumor samples, ORR was 78% (7/9) and median PFS was 11.1 months in patients with secondary ALK mutations co-occurring with ALK fusion, compared with 89% (17/19) and 12.9 months, respectively, in those without ALK mutations. For patients with ctDNA-detectable ALK fusion, ORR was 60% (6/10) and median PFS was 9.2 months in those with secondary ALK mutations, and 50% (10/20) and 21.4 months, respectively, without secondary ALK mutations. The 1 patient with baseline G1202R responded. Six patients had baseline alterations in non-ALK secondary drivers (EGFR, KRAS, NRAS, BRAF, MET); none had response. Emergent G1202R was noted in 3 patients and ALK amplification in 3 patients. CONCLUSION:Brigatinib showed substantial activity in crizotinib-pretreated ALK-positive NSCLC with ALK-dependent mechanisms of resistance. Patients with non-ALK canonical drivers did not respond to brigatinib, suggesting alternative therapeutic approaches in that cohort.

TPS8659 Background: Tumor-infiltrating lymphocyte (TIL) therapy with lifileucel plus pembrolizumab (pembro) demonstrated durable and deepening responses with an objective response rate (ORR) of 64.3% in patients (pts) with anti–PD-1/PD-L1–naive, EGFR wild-type, locally advanced or metastatic non-small cell lung cancer (mNSCLC) in cohort 3A of the IOV-COM-202 phase 2 open-label study (NCT03645928), with 4 of 5 ongoing responses lasting >20 months from start of therapy and no new safety signals. We added two new cohorts within this basket study, 3D and 3E, which evaluate if adding lifileucel to pembro ± pemetrexed in the maintenance phase of standard-of-care (SOC) therapy (from tumors procured in treatment-naive pts [3D] versus those who had already started receiving SOC chemotherapy [3E]) is feasible and provides added benefit with an acceptable safety profile. Incorporating TIL with current SOC has the potential to address a major unmet need by improving outcomes that are not durable or adequate for many pts with NSCLC. Methods: Pts have tumor resection before cycle 1 (3D) or between cycles 1 and 4 (3E) of frontline platinum-doublet chemotherapy plus pembro. After completion of SOC chemotherapy, a dose of pembrolizumab will be given followed by nonmyeloablative lymphodepletion (NMA-LD) (day −5 to day −3: cyclophosphamide 20 mg/kg/day; day −5 to day −2: fludarabine 25 mg/m2/day). Lifileucel is administered on day 0, followed by IL-2 continuous infusion on days 1–4. Following lifileucel and IL-2, pembro (plus pemetrexed if nonsquamous histology) will be continued for up to 2 years or until disease progression or unacceptable toxicity. Eligible adults have histologically confirmed mNSCLC, no actionable mutations with effective targeted therapy, no prior systemic therapy for metastatic NSCLC, ECOG performance status 0–1, estimated life expectancy ≥6 mo, and ≥1 resectable lesion >1.5 cm in diameter to generate lifileucel. Prior organ allograft or cell transfer therapy, symptomatic brain metastases, current systemic steroid therapy >10 mg/day of prednisone or other steroid equivalent, and active illnesses or autoimmune disorders are not permitted. Endpoints include ORR, complete response rate, disease control rate, and PFS by investigator-assessed RECIST v.1.1, OS, percentage of manufactured lifileucel drug products that meets release specification, and incidence of grade ≥3 treatment-emergent adverse events. Selected exploratory endpoints include in vivo T-cell persistence, correlative biomarkers, and circulating tumor DNA. Enrollment of approximately 20 pts per cohort will take place in Europe and North America. Clinical trial information: NCT03645928 .

Thymomas and thymic carcinomas are rare mediastinal tumors that originate in the thymus. Patients with thymoma may experience symptoms associated with autoimmune paraneoplastic diseases (such as myasthenia gravis), which typically do not occur in patients with thymic carcinoma. The NCCN Guidelines for Thymomas and Thymic Carcinomas provide guidance for the diagnosis, treatment, and surveillance of patients with thymoma and thymic carcinoma. Involvement of a multidisciplinary team with experience treating thymomas and thymic carcinomas is highly recommended.

BACKGROUND:The use of first-line single agent immunotherapy in patients with advanced NSCLC and ECOG PS ≥ 2 remains controversial, as this frail population has been largely excluded from pivotal clinical trials. Real-world evidence suggests that although median survival is poor, a subset of these patients may achieve long-term benefit. METHODS:We analyzed data from the Pembro-Real 5Y registry, a global real-world dataset with > 5 years follow-up. The cohort included patients with advanced NSCLC, PD-L1 TPS ≥ 50 %, treated with first line pembrolizumab outside of clinical trials. Univariable analyses were conducted to identify descriptive characteristics associated with survival. To address the complexity of long-term outcome prediction, we integrated Elastic Net regression and a transformer-based AI model (NAIM). The Elastic Net model was employed to mitigate collinearity and select relevant prognostic factors, while NAIM was used to explore non-linear, time-dependent interactions between variables. Endpoints included overall survival (OS) and 5-year survival rates. RESULTS:Out of 1050 patients, 161 patients with ECOG PS ≥ 2 were included, showing a median OS of 5.4 months (95 % CI: 3.8-7.8), and a 5-year survival rate of 13.0 % (95 % CI: 8.1-19.9). Univariable analysis indicated that no single baseline variable was strongly predictive of 5-year survival, except for TMB, KRAS, and BRAF status, which were significantly limited by missingness. Elastic Net identified only two significant predictors of 5-year survival: high TMB (with unstable confidence intervals) and KRAS mutation. NAIM provided a dynamic perspective, confirming that bone metastases and baseline corticosteroid use were strong predictors of early mortality, whereas BMI increase and systemic health markers/host factors (e.g., hypertension and dyslipidemia) gained importance in long-term survivors. However, NAIM exhibited a notable performance drop from training to validation suggesting overfitting and the challenge of modeling long-term outcomes using baseline static variables. CONCLUSIONS:Despite the overall poor prognosis, a subset of patients with ECOG PS ≥ 2 achieves long-term survival with pembrolizumab monotherapy, indicating that performance status alone should not preclude treatment in all cases. Our analysis highlights the limitations of traditional statistical approaches and AI-driven models in predicting long-term benefit in this heterogeneous population. Future efforts should focus on refining hybrid modeling strategies and incorporating prospective validation to better identify those who may benefit from immunotherapy beyond short-term expectations.

The NCCN Guidelines for Non-Small Cell Lung Cancer (NSCLC) provide recommendations for the treatment of NSCLC. These NCCN Guidelines Insights discuss recent updates to the NCCN Guidelines, with a focus on systemic therapy options for the treatment of patients with nonmetastatic NSCLC and the corresponding molecular testing considerations.

Background Pembrolizumab monotherapy is an established front-line treatment for advanced non-small cell lung cancer (NSCLC) with programmed cell death-ligand 1 (PD-L1) tumor proportion score (TPS)≥50%. However, real-world data on its long-term efficacy remains sparse.Methods This study assessed 5-year outcomes of first-line pembrolizumab monotherapy in a large, multicenter, real-world cohort of patients with advanced NSCLC and PD-L1 TPS≥50%, referred to as Pembro-real 5Y. Individual patient-level data (IPD) from the experimental arm of the KEYNOTE-024 trial were extracted (KN024 IPD cohort) to compare the long-term outcomes between the two cohorts. To further assess the reproducibility of clinical trial results, we reconstructed the “KN024 look-alike” cohort by excluding patients with an Eastern Cooperative Oncology Group-performance status (ECOG-PS)≥2, those requiring corticosteroids with doses ≥10 mg of prednisolone/equivalent, patients with positive/unknown epidermal growth factor receptor/anaplastic lymphoma kinase genotype, and those with pre-existing autoimmune disease. We additionally provided a hierarchical organization of determinants of long-term benefit through a conditional inference tree analysis.Results The study included 1050 patients from 61 institutions across 14 countries, with a median follow-up of 70.3 months. The 5-year survival rate was 26.9% (95% CI: 23.8% to 30.2%), and median OS was 21.8 months (95% CI: 19.1 to 25.7), while 32 (3.0%) patients who achieved a complete response remained progression-free at the data cut-off. The KN024 look-alike cohort had a 5-year survival rate of 29.3% (95% CI: 25.5% to 33.6%) and a median OS of 27.5 months (95% CI: 22.8 to 31.3). Neither the overall study population nor the KN024 look-alike cohort exhibited significantly different OS compared with the KN024 IPD cohort. By the data cut-off, 1015 patients (96.7%) had permanently discontinued treatment: 659 (64.9%) due to progressive disease, 156 (15.4%) due to toxicity, 77 (7.6%) due to treatment completion, and 106 (10.4%) due to other reasons. Overall, 222 participants (21.1%) were treated for a minimum period of 24 months, among them the 5-year survival rates were: 31.7%, 72.7%, 78.6%, 84.2% for patients who discontinued treatment due to progressive disease, toxicity, treatment completion, and other reasons, respectively.Conclusion This study provides valuable real-world evidence that confirms the long-term efficacy of pembrolizumab outside of clinical trials. Hierarchical organization indicates ECOG-PS, age and PD-L1-TPS as the most important predictors of 5-year survival, potentially informing clinical practice.

Thymomas and thymic carcinomas are rare mediastinal tumors that originate in the thymus. Patients with thymoma may experience symptoms associated with autoimmune paraneoplastic diseases (such as myasthenia gravis), which typically do not occur in patients with thymic carcinoma. The NCCN Guidelines for Thymomas and Thymic Carcinomas provide guidance for the diagnosis, treatment, and surveillance of patients with thymoma and thymic carcinoma. Involvement of a multidisciplinary team with experience treating thymomas and thymic carcinomas is highly recommended.

ASCL1 overexpression does not affect PC9 or H1975 cells. Drug response data in two additional lung cancer cell lines overexpressing ASCL1.

Supplementary Figure 1. Available tumor tissue samples and blood samples.

Abstract The majority of EGFR mutant lung adenocarcinomas respond well to EGFR tyrosine kinase inhibitors (TKI). However, most of these responses are partial, with drug-tolerant residual disease remaining even at the time of maximal response. This residual disease can ultimately lead to relapses, which eventually develop in most patients. To investigate the cellular and molecular properties of residual tumor cells in vivo, we leveraged patient-derived xenograft (PDX) models of EGFR mutant lung cancer. Subcutaneous EGFR mutant PDXs were treated with the third-generation TKI osimertinib until maximal tumor regression. Residual tissue inevitably harbored tumor cells that were transcriptionally distinct from bulk pretreatment tumor. Single-cell transcriptional profiling provided evidence of cells matching the profiles of drug-tolerant cells present in the pretreatment tumor. In one of the PDXs analyzed, osimertinib treatment caused dramatic transcriptomic changes that featured upregulation of the neuroendocrine lineage transcription factor ASCL1. Mechanistically, ASCL1 conferred drug tolerance by initiating an epithelial-to-mesenchymal gene-expression program in permissive cellular contexts. This study reveals fundamental insights into the biology of drug tolerance, the plasticity of cells through TKI treatment, and why specific phenotypes are observed only in certain tumors. Significance: Analysis of residual disease following tyrosine kinase inhibitor treatment identified heterogeneous and context-specific mechanisms of drug tolerance in lung cancer that could lead to the development of strategies to forestall drug resistance. See related commentary by Rumde and Burns, p. 1188