Abstract D074: Variations in genomic testing across cancer sites and by demographic characteristics
Authors: Koroukian Siran , Dong Weichuan , Rose Johnie , Schumacher Fredrick , Markt Sarah 
Published: September 2020

Study Objective: Genomic testing is essential to identify the best treatment modalities for certain cancers; yet, its uptake has been relatively low, especially among disadvantaged subgroups of the population. The aim of this study is to identify demographic and clinical factors associated with receipt of genomic testing in Ohioans diagnosed with either incident female breast, kidney, bladder, prostate, colorectal, or lung cancer. Methods: We used data from the 2009 linked Ohio Cancer Incidence Surveillance System and Medicare files, and identified genomic testing using the appropriate procedure codes in claims data. Our study population included 10,945 patients. Independent variables examined were age at diagnosis (&lt; 65, 65-74, 75+), sex, race (White or All Other), dual enrollment in the Medicare and Medicaid program (or ‘dual’) as a marker for low income and heightened vulnerability, and advanced stage at diagnosis (Regional/Distant versus Local stage). We conducted multivariable logistic regression analysis to identify correlates of genomic testing by cancer site. Results: For all cancer sites combined, 11.1% were younger than 65, and 40.6% were older than 75 years of age. Eighty eight percent were White, 47.0% were women, 13.9% were duals, and one third were diagnosed with advanced-stage cancer. Overall, only 19.5% underwent genomic testing, ranging from a low of 6.7% in prostate cancer patients, to a high of 39.3% in breast cancer patients. In addition, we observed considerable variation in genomic testing by age, race, sex, dual status, and cancer stage across cancer sites. Adjusting for the independent variables listed above, being 75 years of age or older was significantly and positively associated with increased likelihood of undergoing genomic testing in breast (adjusted odds ratio: 1.17, 95% confidence interval: 1.04, 1.32), kidney and bladder combined (1.29 (1.09, 1.53)), and prostate cancer patients (1.45 (1.12, 1.89)). Advanced-stage disease was associated with increased likelihood of genomic testing in breast and colorectal cancer patients (1.40 (1.17, 1.67) and 3.07 (2.30, 4.11), respectively), but with decreased likelihood in kidney and bladder cancer patients (0.66 (0.48, 0.91)). Finally, we note that White patients with lung cancer were significantly more likely than others to undergo genomic testing (2.49 (1.29, 4.78)). Conclusion: Our data from 2009 provide baseline statistics on genomic testing uptake in Ohio. Data for subsequent years will help us to assess trends in providing personalized medicine.

Citation Format: Siran Koroukian, Weichuan Dong, Johnie Rose, Fredrick Schumacher, Sarah Markt. Variations in genomic testing across cancer sites and by demographic characteristics [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D074.