Abstract PR018: Feasibility of serial microbiome collection in a multi-site neoadjuvant pancreatic cancer clinical trial allowing for a diverse patient population
Authors: Rogers Sherise C. , Nassour Ibrahim , Thomas Ryan , Sahin Ilyas , Ramnaraign Brian , Russell Karen , Hughes Steven , Hitchcock Kathryn , Kayaleh Omar , Turk Anita , Lee Ji-Hyun , DeRemer David , Allegra Carmen , George Thomas 
Published: December 2023

Abstract
Background: Pancreatic cancer portends a very poor prognosis. It is the third leading cause of cancer deaths in the United States. African Americans have a 50- 90% increased incidence of pancreatic cancer in comparison to other racial groups. 20% of patients with pancreatic cancer present with early-stage disease and will have a median overall survival of 2.5 years if able to undergo surgical resection. There is a desperate need to discover novel ways of treating pancreatic cancer. Understanding of the microbiome may be informative to overcoming chemotherapy resistance, toxicity and improving outcomes and disparities. The aim of this study is to (1) identify changes in the intestinal microbiota during neoadjuvant treatment of pancreatic ductal adenocarcinoma that correlate with treatment response and (2) identify changes in the intestinal microbiota during neoadjuvant treatment of pancreatic ductal adenocarcinoma that correlate with treatment toxicity in a diverse patient population. Methods: Patients with resectable or borderline resectable pancreatic cancer who are enrolled in a multi-site clinical trial (NCT03483038) receiving neoadjuvant NEO-Nali-IRI (oxaliplatin, liposomal irinotecan and 5- FU) followed by surgical resection were asked to provide serial microbiome collections of saliva, urine, blood, and stool with a dietary log during the following four (or five) time points: at baseline, mid-therapy (after C4), at completion of chemotherapy (after C8), after radiation if applicable, and at 4-6 weeks post-operative. Participants were given stool collection kits during clinic visits for home sample acquisition. All stool samples were mailed to the University of Florida Health Cancer Center Microbiome Biorepository. Saliva, urine and blood were collected during clinic visits. Demographics, stage, medical history and concurrent medications including antimicrobics and probiotics, chemotherapy dose-reductions, delays, discontinuations, adverse events, safety adverse events, attribution of causality, and hospitalizations were obtained. Outcomes include imaging response using RECIST criteria, CA 19-9 trend, development of metastatic disease, and the ability to proceed to definitive surgical resection. DNA will be extracted from stool and analyzed using 16S rRNA sequencing methods to determine signatures and biodiversity. Descriptive statistics and correlative analysis will be reported. Continuous and categorical variables will be compared with Student’s t-test and Chi-squared test. Multiple groups will be compared by ANOVA. Kaplan-Meier logistic regression will be performed to compare outcomes between the different microbiota groupings. Conclusion: Serial microbiome collection from a multi-site clinical trial is feasible during neoadjuvant chemotherapy for pancreatic cancer and can increase the diversity of the sample population.
Citation Format: Sherise C. Rogers, Ibrahim Nassour, Ryan Thomas, Ilyas Sahin, Brian Ramnaraign, Karen Russell, Steven Hughes, Kathryn Hitchcock, Omar Kayaleh, Anita Turk, Ji-Hyun Lee, David DeRemer, Carmen Allegra, Thomas George. Feasibility of serial microbiome collection in a multi-site neoadjuvant pancreatic cancer clinical trial allowing for a diverse patient population [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr PR018.