Abstract B79: Disparities in access to the EGFR assay
Authors: Lynch Julie A. , Lathan Christopher S. 
Published: June 2012

Introduction: This study examines regional and site of care differences in access to lung tumor genotyping. We test the hypothesis that utilization rate by community hospitals of the epidermal growth factor receptor (EGFR) assay is a function of presence and number of National Cancer Institute (NCI) designated cancer centers within the state. Additional hypotheses to be tested are: Community hospital participation in NCI clinical research groups increases the likelihood and rate of utilization of the EGFR assay. Counties with higher percentage of Blacks, lower education and income levels are likely to have lower rates of EGFR assay utilization.

Description of the research: Genzyme Genetics holds the license to distribute and market the EGFR assay. It provided the authors a dataset which contained hospital name, city, state, zip code, patient gender, and payor for EGFR assays processed in fiscal year 2010. Genzyme has not enforced its license with cancer centers that have CLIA approved labs which independently process EGFR assays. Therefore, this data set represents community hospital utilization of the EGFR assay.

The Genzyme data was merged with publicly available information detailing county/state level lung cancer incidence, location of cancer centers (obtained from the Center for Disease Control (CDC) and NCI), population demographic, educational and income statistics published by the Census bureau, and longitude and latitude data for each institution ordering the EGFR assay and for NCI designated cancer centers.

Multiple regression analysis was conducted at the state level to analyze the relationship between the community hospital utilization rate of the EGFR assays (defined as the number of EGFR assays ordered by community hospitals divided by the lung cancer incidence rate in that state) the number of NCI cancer centers, race, education, and income levels within that state. A similar analysis was conducted with number of cancer centers replaced by presence of cancer center.

Preliminary results aggregated at the state level were obtained for this abstract. Analysis is ongoing and results presented at the conference will be detailed at the zip code level with location and distance to NCI cancer center calculated and mapped.

Further, NCI has provided an unencrypted version of its provider of service (POS) file which includes variables about community hospital participation in NCI sponsored clinical research groups. Relationship between EGFR utilization rate and community hospital participation in clinical research will also be analyzed.

Summary of results: The presence and number of NCI cancer centers were both highly significant with p values of .023 and .000. When the cancer center variables were included in the models, other variables were insignificant. However, when cancer center variables were removed from the models, income over $75,000 trended toward significance with a p value of .08.

Conclusion: Preliminary analysis illustrates that important regional and site of care differences exist in utilization of the EGFR assay at community hospitals. As molecular diagnostic technologies become an increasingly important component of lung cancer care, oncology biomarker and drug development, there is growing urgency to elucidate structural barriers impeding access to advanced cancer technologies and limiting diversity of tumor tissue included in translational research.

Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):B79.