The Importance of Altruism to Biomarker Development for Pancreatic Cancer.

11626 Background: Longitudinal donation of tissue and health information by patients with pancreatic ductal adenocarcinoma (PDAC) is critical to validating algorithms for precision treatment. Unlike therapeutic trials offering potential survival benefit, factors motivating long-term participation in biomarker studies are poorly understood. We hypothesized that long-term participation (PART) depends on identifiable factors motivating study volunteers in non-therapeutic biomarker studies. Methods: A prospective, single-institution biomarker study was screened to identify participants with, or at elevated risk for, PDAC and periampullary cancer (Jul 2015-Dec 2018). Study consent precluded individual receipt of value or research benefit. Detailed biospecimen and clinical data (n = 294) were analyzed using multivariable modeling and Bayesian AI (bAIcis) to characterize motivators of PART. Results: Of 294 participants, 185 had PDAC (63%); 89 had premalignant lesions (30%) or tumors (20; 7%) mimicking PDAC. Mean age was 68 years, 54% male, 26% with prior cancers, and 18% family PDAC history. Treatment was not indicated (37% no cancer), potentially curative (27%), non-curative (35%); or refused (1.4%). Bayesian AI showed PDAC diagnosis to be the leading predictor of PART. Using multivariable modeling and adjusting for the competing risk of death, none of the following domains predicted PART: demographics, perceived personal/family cancer risk, health insurance type, median income, housing price, travel time/distance or charitable expense, or primary institution providing clinical treatment. The following motivators were significant predictors of PART: worsening symptoms (McGill Brisbane > 9; HR 0.54; p = 0.045), non-curative treatment (HR 0.55; p = 0.042); and shorter AJCC predicted survival (HR 0.77, p = 0.042). Conclusions: Volunteers with symptomatic PDAC and shorter predicted survival who received non-curative treatment were more motivated to participate in biomarker discovery. Volunteers were undeterred by apparent self-interests such as travel time, insurance type, income, charitable expense, and personal life expectancy. We attribute these findings to altruistic behaviors among patients most likely to die of PDAC.