The advent of advanced biomolecular technologies for detecting molecular and genomic signatures of individual tumors has transformed oncology care, introducing proven methodologies that can inform treatment with matched targeted therapies and predict response at the individual patient level. However, access to these technologies has been hampered by multiple barriers, most notably price and obtainability. Other barriers include lack of knowledge of available technologies, concerns about value, and outdated infrastructures that impede critical operations within the clinic or laboratory. Accessibility barriers to advanced biomolecular testing are critically important to patient care, as new technological advances in molecular medicine continue to outpace the implementation of solutions. Given the proven evidence for improved patient outcomes with precision oncology medicines, it is imperative to understand the value afforded by these technologies. The purpose of this narrative review is to describe existing and emerging barriers to access and present a "roadmap to access" that will facilitate the urgently needed discussions to identify solutions for improving access. Implementation of these solutions will raise awareness of available technologies and treatments and their prognostic significance, improve evidence collection for demonstration of value, and fortify clinical and laboratory infrastructure and operations.

Abstract Introduction: Approximately 50% of patients with EGFR-mutated advanced non-small cell lung cancer (NSCLC) develops brain metastases (BM), which is associated with a poor prognosis. Mutations in TP53 are associated with earlier development of resistance to EGFR tyrosine kinase inhibitors, but it is unclear whether patients who develops BM have a higher prevalence of TP53 mutations. Analyses of circulating tumor DNA (ctDNA) in blood have been established as a good alternative to tissue biopsies to assess the genomic landscape of NSCLC. In this study, we aim to analyze ctDNA from patients with advanced EGFR-mutated NSCLC to investigate the prevalence of TP53 mutations in patients with BM, and to explore whether patients with BM exhibit a distinct ctDNA profile compared to patients without. Materials and Methods: Plasma samples collected before treatment commenced from 97 of the 100 patients with EGFR-mutated advanced NSCLC enrolled in the First-line Treatment With Osimertinib in EGFR-mutated Non-small Cell Lung Cancer study (The FIOL study: NCT03804580) were analyzed. Patients were split into cohorts with (n=44) and without BM (n=53) at baseline. The cell-free DNA was isolated and sequenced with targeted next-generation sequencing with the AVENIO ctDNA Surveillance Panel (Roche) containing 197 lung cancer-related genes. Results: Mutations in ctDNA were found in 83 patients (85.6%), with 6 patients with BM having no ctDNA mutations and 8 patients without BM having no ctDNA mutations. Besides EGFR mutations, TP53 was the most frequently mutated gene, with 42 patients (43.3%) harboring TP53 mutations. There was no significant difference in the prevalence of TP53 mutations between the cohort with BM (n=23) and the cohort without (n=19), (p=0.15). There was no difference in the number of identified mutations in the two cohorts (BM: median: 2 (range: 0-6), without BM: median: 2 (range: 0-11), p=0.71). Patients with BM had a numerically lower ctDNA level (median: 45.5 mutant molecules/mL), than patients without BM (median: 75.9 mutant molecules/mL), though the difference was not statistically significant (p=0.68). Conclusion: Prevalence of TP53 mutations in plasma collected before osimertinib treatment initiation in advanced EGFR-mutated NSCLC was similar between patients with and without BM at baseline. Furthermore, there was no difference in the ctDNA profile between these two cohorts. Future experiments will clarify the impact of TP53 mutations in patients with or without BM. Citation Format: Simone Stensgaard, Inger Johanne Z. Eide, Elin Marie Stensland, Åslaug Helland, Simon Ekman, Karin H. Hansen, Saulius Cicenas, Bjørn Henning Grønberg, Peter Meldgaard, Boe S. Sørensen, Odd Terje Brustugun. Mutated TP53 prevalence in EGFR-mutated advanced non-small cell lung cancer patients with brain metastases [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 2413.

Supplemental Table I. Prognostic clinicopathologic variables as predictors for DSS in 797 NSCLS (univariate analyses,log-rank test)

Supplemental Figure 1. Disease-specific survival curves according to low, intermediate and high stromal CD8+ T-cell density in the Danish cohort (Odense University Hospital, n = 178). (A) Score from the invasive margin tumor area, (B) score from the central parts of the tumor. The maximum score for each patient was used.

Introduction Persistent inflammation and immune activation in the lungs are associated with adverse outcomes such as radiation pneumonitis (RP) and poor survival in non-small-cell lung cancer (NSCLC) patients. However, it is unknown how this is reflected by leukocyte activation markers in serum. Objective The aim was to evaluate the serum levels of activation of different leukocyte subsets and to examine those in relation to the pathogenesis of RP and survival in NSCLC. Methods We analyzed the serum levels of MPO, sCD25, sTIM-3, sPD-L1, sCD14, sCD163, CCL19 and CCL21 in 66 inoperable NSCLC patients with stage IA-IIIA disease. The patients were treated with stereotactic body radiation therapy (SBRT) or concurrent chemoradiation therapy (CCRT), followed by regular blood sampling for 12 months after treatment and for 5 years for survival. Results Nineteen (29%) patients developed RP, which occurred more frequently and earlier in patients receiving CCRT than in those receiving SBRT. Increases in sCD25, sTIM-3 and CCL21 levels were observed at the last 6 months of follow-up in patients who had RP after SBRT. Patients who had RP after CCRT had higher sTIM-3 levels during the first 3 months of follow-up. Baseline sCD25 was independently associated with both 2- and 5-year mortality outcomes, while baseline sTIM-3 was independently associated with 2-year mortality. Conclusion We showed that T cell activation and exhaustion markers such as sCD25 and sTIM-3 are enhanced in patients developing RP and are associated with poor survival in NSCLC.

9001 Background: Cancer immunotherapy (CIT) can have a positive impact on OS that exceeds response rate or PFS effects, termed post progression prolongation of survival (PPPS). This effect can also result from unconventional CIT response due to tumor immune infiltration or delayed response, reducing reliability of RECIST v1.1 (RECIST) PD as an indicator of treatment failure. In the primary analysis (N = 850) of OAK, a study of atezo vs docetaxel (doc) in 2L/3L NSCLC, OS favored atezo (HR 0.73; 95% CI: 0.62, 0.87), despite similar PFS between arms (HR 0.95; 95% CI: 0.82, 1.10). Here we evaluate clinical benefit from TBP, defined by post PD tumor regression, OS and safety. Methods: Patients (pts) received atezo 1200 mg IV q3w until PD or loss of clinical benefit per investigator or doc 75 mg/m 2 IV q3w until PD per RECIST. No crossover was allowed. Primary outcome measure: OS. Atezo TBP pts were evaluated for post PD tumor change and for safety pre and post PD. OS from time of PD per RECIST was evaluated in both arms (data cutoff, July 7, 2016; minimum follow-up, 19 mo). Results: Among 332 atezo pts with PD, 51% (n = 168) continued atezo TBP; 7% (12/168) achieved subsequent response in target lesions (≥ 30% reduction from new baseline at PD); 49% (83/168) had stable target lesions (best change between +20% and −30%). mOS was 12.7 mo (95% CI: 9.3, 14.9) post PD for pts on atezo TBP (Table). Atezo TBP was not associated with increased safety risk. Conclusions: This is the first report from a Phase III study of CIT in NSCLC to evaluate post PD OS in pts continuing treatment beyond RECIST PD. Atezo TBP was associated with high frequency of stable or decreased target lesions, mOS > 1 year and a tolerable safety profile, all supporting prolonged treatment benefit consistent with PPPS. NCT02008227 Clinical trial information: NCT02008227. [Table: see text]