Abstract INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) has a poor 5-year survival rate. PDAC surveillance is recommended in high-risk individuals (HRIs) with strong PDAC family history or a pathogenic germline variant (PGV) in a PDAC susceptibility gene. We aimed to explore a potential correlation between genetic status, extent of family history, pancreatic findings, and surveillance implications in heterogeneous PDAC HRIs. METHODS: from January 2015 up to date, a total of 340 HRIs from 291 families visited our pancreatic cancer high-risk clinic. Surveillance included annual clinic visits, EUS/MRI imaging, genetic and laboratory blood testing. Participants completed a questionnaire that included personal and familial medical history, dietary habits, daily activities with emphasis on smoking habits, alcohol use, and physical activity. RESULTS: Our cohort was divided into 3 groups: familial pancreatic cancer that include individuals with family history of 2 or more first degree family (FDR) with PDAC (FPC; 96 individuals), familial non-FPC, families with at least 2 biological relatives with PDAC and not meeting FPC criteria, (119 individuals), and hereditary pancreatic cancer (PC), individuals with PGV in a PC susceptibility gene and a family member with PDAC carrying the same PGV (124 individuals). The cohort average age at first visit was 54 years with 44% male and 56% female ratio. Seventy percent of the cohort was of Jewish Ashkenazi decent. Genetic testing was performed in several steps, first BRCA1/2 founder mutations was performed in all individuals followed by genetic panels and whole exome sequencing (WES). PGVs were detected in 36.4% of all families. There was no significant difference in the genetic finding between the FPC and non-FPC groups (11% and 9.6% respectively). Of the study cohort 35% were screened by EUS and 8% by MRI/MRCP. Pancreatic lesions detected included 11 cases of new PDAC (3.2%), 69 cystic lesions (20.3%), 43 cases early chronic pancreatitis (12.6%) and 11 cases of main pancreatic duct dilation (3.2%). To better understand the risk of PDAC development in HRIs we recently added a novel cell-free chromatin blood test for early cancer detection (in collaboration with SENSEERA, Israel) and compared it to EUS imaging results. The test provides multidimensional epigenetic information that sheds light on the identity and the transcriptional state of the cells that are dying in the body of the patient. Our preliminary results show nice separation between the healthy control and PC groups. PC HRIs show slight increase in score compared to the general population while individuals with worrisome features show substantial increase compared to HRIs with no EUS findings. DISCUSSION: Surveillance seems effective for detection of early-stage PDAC and precursor lesions. However, screening strategy can be improved by adding newer modalities like chromatin-based tests that might help to further define the risk of cancer development in HRIs. Citation Format: Merav Ben Yehoyada, Erez Scapa, Oren Shibolet, Guy Rosner. Surveillance outcome in individuals at high risk of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B025.