Abstract 784: Association of neighborhood socioeconomic status and aggressive non-small cell lung cancer biology
Authors: Wing Sam , Sosa Ernesto , Benmarhnia Tarik , Yang Jiue-An , Gray Stacy , Jankowska Marta , Erhunmwunsee Loretta 
Published: July 2021

Introduction: Lung cancer is the leading cause of cancer-related deaths in the US. While smoking remains the most common cause for non-small cell lung cancer (NSCLC), less research exists on the role of adverse social conditions and neighborhood socioeconomic status (nSES) in the development of specific NSCLC somatic mutations. Neighborhood conditions can be influenced by economic, housing, education, transportation, and environmental factors. Understanding the relationship between NSCLC biology and nSES is vital in addressing disproportionately high rates of NSCLC incidence and poor outcomes among marginalized communities in the US. While neighborhood deprivation indices have been linked to aggressive biology in other cancers, the link to somatic mutations in NSCLC is unknown. The purpose of this analysis is to identify relationships between exposure to adverse nSES conditions and somatic KRAS mutations, a marker of aggressive NSCLC biology.

Methods: We analyzed NSCLC patients who received care at the City of Hope Comprehensive Cancer Center in Duarte, CA from 2015-2018 and received somatic KRAS testing of their lung tumor tissue as a part of their care. The patients' medical record was abstracted for data including demographics and disease characteristics. The patients' home address was geocoded and assigned a census tract-level exposure to several indices of nSES conditions including the California Health Places Index (HPI), the US Department of Housing and Urban Development Labor Market Engagement Index (LME), and the Area Deprivation Index (ADI). We used several logistic regressions to model the presence of somatic KRAS mutations in relation to exposure to various adverse nSES conditions. Odds ratios (ORs) were adjusted for age at diagnosis, sex, cigarette smoking, race/ethnicity, insurance status, cancer stage, cancer histology, and exposure to PM2.5.

Results: Of 426 eligible NSCLC patients, 28% tested positive for a KRAS mutation, 54% were non-Hispanic White, 66% were stage IV, and 83% had adenocarcinomas. The risk of a KRAS mutation was significantly elevated among patients living in places with lower HPI scores (OR 1.92, 95% CI: 1.11 - 3.32) and lower LME (OR 1.16, 95% CI: 1.05 - 1.28). In adjusted models, PM2.5, ADI, and other nSES indices were not significantly associated with risk of a KRAS mutation.

Conclusions: We found that NSCLC patients living in deprived neighborhood conditions as measured by the California HPI and LME were more likely to have a somatic KRAS mutation. This relationship shows that nSES may be an important determinant of aggressive NSCLC biology. However, our results also indicate that deprivation is a complex mixture of domains and regionally specific influences. These findings indicate that future research may need to consider locally specific nSES measures as a dynamic marker of neighborhood conditions in addition to nationally derived indexes such as the ADI.

Citation Format: Sam Wing, Ernesto Sosa, Tarik Benmarhnia, Jiue-An Yang, Stacy Gray, Marta Jankowska, Loretta Erhunmwunsee. Association of neighborhood socioeconomic status and aggressive non-small cell lung cancer biology [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 784.