Nicole A. Toney, MPH, Sara A. Jackson, PhD, Christina M. Narick, MD, Sydney D. Finkelstein, MD
Interpace Diagnostics Corporation, Pittsburgh, PA
Introduction: Currently, guideline recommended surveillance of pancreatic cysts is based on low quality evidence, as the natural history of such lesions is not well understood. Our study aimed to review pancreatic cystic lesions serially tested by an integrated molecular pathology (IMP) to better understand their natural history and their resulting risk classifications over time.
Methods: We conducted retrospective data review of patients that underwent ≥2 endoscopic ultrasound-guided fine needle aspirations (EUS-FNAs) of their pancreatic cyst, each of which had IMP testing as part of standard of care (PancraGen™, Interpace Diagnostics) between April 2012-March 2019. The four category IMP result classifies pancreatic cysts as either low risk (Benign and Statistically Indolent [SI]), moderate risk (Statistically High Risk [SHR]) or high risk (Aggressive).
Results: 2,167 pancreatic cysts underwent serial IMP testing. The median number of serial tests performed was 2. The majority of cysts serially tested had time intervals between < 1 year and 1-2 years (66%, 1,442/2,167), with 10% (208/2,167) having testing with a >4 year time interval (Table 1). Among cases serially tested, 86% initially had a low risk IMP result of which 92% remained low risk at follow-up EUS-FNA while 8% progressed to a moderate/high risk IMP classification. 99% of diagnostic progression was only to moderate risk IMP. Conversely, among cases serially tested, 14% initially had moderate/high risk IMP results of which 21% remained moderate/high risk at follow-up while 79% regressed to low risk IMP classification. >99% of diagnostic regression was from moderate risk IMP.
Discussion: Examining molecular progression and regression of pancreatic cysts over time can lead to a better understanding of their natural history, which can help guide surveillance intervals. The majority of cases (92%) that initially had low risk IMP results remained low risk overtime, supporting less frequent surveillance intervals. Of those that progressed, 99% were only to moderate risk levels where diagnostic regression most often occurs.
Citation: Nicole A. Toney, MPH, Sara A. Jackson, PhD, Christina M. Narick, MD, Sydney D. Finkelstein, MD. P0016 - SERIALLY MOLECULAR TESTING OF PANCREATIC CYST FLUID OVER TIME: PROGRESSION AND REGRESSION. Program No. P0016. ACG 2019 Annual Scientific Meeting Abstracts. San Antonio, Texas: American College of Gastroenterology.