Frequency of somatic mutations in solid tumor malignancies from inner city minorities: A single center study.

person Maria Cristina Cuartas Mesa John H. Stroger, Jr. Hospital of Cook County, Chicago, IL info_outline Maria Cristina Cuartas Mesa, Thomas Stiles Bemis, Deimante Tamkus, Shweta Gupta

Authors person Maria Cristina Cuartas Mesa John H. Stroger, Jr. Hospital of Cook County, Chicago, IL info_outline Maria Cristina Cuartas Mesa, Thomas Stiles Bemis, Deimante Tamkus, Shweta Gupta Organizations John H. Stroger, Jr. Hospital of Cook County, Chicago, IL Abstract Disclosures Research Funding No funding received None. Background: The treatment landscape for solid tumor malignancies continues to change with identification of predictive biomarker targets by next generation sequencing (NGS). However, data from individuals from racial and ethnic minorities are often underrepresented. To bridge this gap, we examined the frequency of actionable biomarker findings with a treatment target outlined in NCCN guidelines in our inner city minority population at John H. Stroger, Jr. Hospital of Cook County. Methods: We examined patients who had FoundationOne CDx or FoundationOne Liquid CDx reports for our adult patients with a solid tumor malignancy between July 2021 through December 2022. We categorized patients as having an actionable biomarker finding if there was a finding reported with a treatment target with indication in a patient’s tumor type as outlined in NCCN guidelines. Statistics were done using t-test, z-test, and chi square tests. Results: A total of 313 patients had a FoundationOne CDx or FoundationOne Liquid CDx report for a solid tumor malignancy. Median age for the population was 64.6 years (range 20-89 years). The majority of patients were African American (50%), followed by Hispanic (31%), Caucasian (13%) and Asian (6%). There were 149 patients (47.6%) that had an actionable biomarker target in their tumor type. Among the 50 total lung adenocarcinoma patients, 20 (40%) had a driver mutation, with 12 (60%) being African American. In 43 colorectal tumors were tested, 16 (37.2%) were KRAS WT, with 6 being African American, 6 Hispanic, and 4 white. Among 27 prostate cancer samples tested, 7 (25.9%) harbored a homologous recombination repair (HRR) gene mutation. Of the patients without an actionable biomarker in their tumor type, 47 patients (15%) had an actionable biomarker finding approved in another tumor type. Of the patients with biomarker targets in another tumor type, mutations in PIK3CA and HRR genes were among the most frequent findings. There were no statistically significant differences in frequency of actionable biomarkers in patient tumor type between gender (P = 0.31) or race (P = 0.63). Conclusions: Our findings showed that nearly half of our patients had a targetable somatic mutation in their tumor type. Even in patients without an actionable biomarker in their specific cancer, those patients may harbor a biomarker finding with an approved target in another cancer. While sample sizes were small to investigate mutational profiles for specific tumor types, future analysis with more samples will allow for better characterization. These findings support increasing NGS testing to better characterize the tumor mutational profiles for our racially underrepresented population, as well as for identifying potential biomarkers for future studies in other tumor types.