Social Determinants of Health (SDoH) significantly influence outcomes across the cancer care continuum. However, systematic identification and integration of social risk factors into care remain limited. Understanding the perspectives of key stakeholders is essential to inform effective SDoH integration in lung cancer surgery. This qualitative study was embedded within a larger investigation of family caregivers (FCGs) and patients undergoing lung cancer surgery at a National Cancer Institute-designated center in Southern California. Semi-structured interviews were conducted with FCGs, healthcare providers, and system/healthcare administrators to explore their views on SDoH and its role in cancer care. Data were analyzed using conventional content analysis. Themes were developed through a collaborative coding and review process, supported by existing literature and expert input to ensure accurate interpretation. Any differences in coding were resolved through discussion, and descriptive statistics were used to summarize caregiver demographics. FCG participants (n=13) were primarily non-Hispanic White females, aged 60–68 years. We identified six major themes, and 19 sub-themes related to SDoH and caregiving burden. Four providers and two administrators (including thoracic surgeons, a nurse practitioner, a public health administrator, and a nurse scientist) emphasized the need for electronic health record (EHR)-based SDoH documentation, interdisciplinary collaboration, and recognition of FCGs as integral to care delivery. Integrating SDoH into lung cancer surgery intake and follow-up care was viewed as particularly challenging due to the clinical emphasis on survival. Given the focus on patient survival, the healthcare system should broaden its approach by integrating SDoH into lung cancer care. This shift toward coordinated, interdisciplinary care is essential for supporting long-term survival. Stakeholder insights highlight the need for systematic documentation, EHR integration, and comprehensive approaches to address social needs and improve outcomes. Dede K. Teteh-Brooks, Madeleine Love, Aldenise P. Ewing, Betty Ferrell, Oluwatimilehin Okunowo, Audrey Shin, Loretta Erhunmwunsee, Dan Raz, Rick Kittles, Jae Y. Kim, Virginia Sun. Lived experiences and systemic barriers in lung cancer surgery: Perspectives from caregivers, clinicians, and administrators on social determinants of health [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr A004.

e20511 Background: While most patients with EGFR-mutant lung cancers respond to osimertinib, resistance inevitably develops. Mechanisms of osimertinib resistance remain inadequately understood. Recent studies suggest a potential link between intra-tumoral bacteria and therapy resistance in cancer. Our previous studies found that the pre-conditioned medium (PCM) of certain bacteria in the Bacteroidetes phylum conferred resistance of all EGFR-TKIs tested. In this study, we specifically investigate the effect of Porphyromonas gingivalis, a common component of the human oral microbiome and the main pathogen responsible for periodontal disease, on osimertinib sensitivity in EGFR mutant lung cancer. Methods: P. gingivalis PCM (P-CM) was applied to EGFR-mutant lung cancer cell lines for 3 days and cell viability was measured. Western blot and receptor tyrosine kinase (RTKs) assay were used to analyze the changes of cell signaling pathways, and the contribution of identified signaling pathway to P. gingivalis-mediated resistance to osimertinib were further validated by rescue experiments. To investigate the existence of P. gingivalis in human lung cancer tissues, we used Fluorescence In Situ Hybridization (FISH) probes specific to P. gingivalis and hybridized probes to a tissue microarray (TMA) containing 3 mm punches of lung adenocarcinoma tissue from 30 patients in duplicate. The underlying mechanisms of osimertinib resistance conferred by P. gingivalis were explored by a combination of bacterial genomic and cellular proteomic approaches. Results: P-PCM led to osimertinib resistance in all EGFR-mutant lung cancer cell lines tested. Both Western blot and RTKs assay showed that phosphorylated insulin-like growth factor 1 receptor (pIGF1R) level significantly increased when P-PCM was applied to PC9 EGFR mutant lung cancer cells. We found that both IGF1R inhibitor (linsitinib) and IGF1R knockdown with siRNA eliminated the effect of P-PCM-mediated osimertinib resistance. We found that two cysteine proteases secreted by P. gingivalis, lysine-specific gingipain (Kgp) and arginine-specific gingipain A (RgpA) led to osimertinib, whereas arginine-specific gingipain B (RgpB), which lacks haemagglutinin/adhesin (HA) region of RgpA had no effect on osimertinib response. We also found that gingipains-mediated osimertinib resistance is independent of enzymatic activity. We detected intra-tumoral P. gingivalis in tumor tissue of 9 (30%) patients by using FISH probes specific to P. gingivalis. Conclusions: Our studies demonstrate that P. gingivalis can induce osimertinib resistance in EGFR-mutant lung cancer cells through secreted gingipains that activate the IGF1R pathway through an enzymatic- independent mechanism. P. gingivalis is frequently detected in human lung cancer tissues , suggesting that therapies targeting P. gingivalis may improve EGFR-TKI response in certain patients with EGFR-mutant lung cancer.

OBJECTIVE:Multimodality treatment for resectable non-small cell lung cancer has long remained at a therapeutic plateau. Immune checkpoint inhibitors are highly effective in advanced non-small cell lung cancer and promising preoperatively in small clinical trials for resectable non-small cell lung cancer. This large multicenter trial tested the safety and efficacy of neoadjuvant atezolizumab and surgery. METHODS:Patients with stage IB to select IIIB resectable non-small cell lung cancer and Eastern Cooperative Oncology Group performance status 0/1 were eligible. Patients received atezolizumab 1200 mg intravenously every 3 weeks for 2 cycles or less followed by resection. The primary end point was major pathological response in patients without EGFR/ALK+ alterations. Pre- and post-treatment computed tomography, positron emission tomography, pulmonary function tests, and biospecimens were obtained. Adverse events were recorded by Common Terminology Criteria for Adverse Events v.4.0. RESULTS:From April 2017 to February 2020, 181 patients were entered in the study. Baseline characteristics were mean age, 65.1 years; female, 93 of 181 (51%); nonsquamous histology, 112 of 181 (62%); and clinical stages IIB to IIIB, 147 of 181 (81%). In patients without EGFR/ALK alterations who underwent surgery, the major pathological response rate was 20% (29/143; 95% confidence interval, 14-28) and the pathological complete response rate was 6% (8/143; 95% confidence interval, 2-11). There were no grade 4/5 treatment-related adverse events preoperatively. Of 159 patients (87.8%) undergoing surgery, 145 (91%) had pathologic complete resection. There were 5 (3%) intraoperative complications, no intraoperative deaths, and 2 postoperative deaths within 90 days, 1 treatment related. Median disease-free and overall survival have not been reached. CONCLUSIONS:Neoadjuvant atezolizumab in resectable stage IB to IIIB non-small cell lung cancer was well tolerated, yielded a 20% major pathological response rate, and allowed safe, complete surgical resection. These results strongly support the further development of immune checkpoint inhibitors as preoperative therapy in locally advanced non-small cell lung cancer.