Quantifying Patient Risk Threshold in Managing Pancreatic Intraductal Papillary Mucinous Neoplasms.

Objective: We aimed to better understand patients' treatment preferences and quantify the level of cancer risk at which treatment preferences change (risk threshold) to inform better counseling of patients with intraductal papillary mucinous neoplasms (IPMNs).

Summary Background Data: The complexity of IPMN management provides an opportunity to align treatment with individual preference.

Methods: We surveyed a sample of healthy volunteers simulating a common scenario: undergoing an imaging study that incidentally identifies an IPMN. In the scenario, the estimated risk of cancer in the IPMN was 5%. Patients were asked their treatment preference (surgery or surveillance), to quantify the level of cancer risk in the IPMN at which their treatment preference would change (i.e. risk threshold), and their level of cancer anxiety as measured on a 5-point Likert scale. We examined associations between participant characteristics, treatment preferences, and risk threshold using multivariable linear regression.

Results: The median risk threshold among the 520 participants was 25% (IQR 2.3-50%). The risk threshold had a bimodal distribution: 40% of participants had a risk threshold between 0-10% and 47% had a risk threshold above 30%. When informed that the risk of cancer was 5%, 62% of participants (n=323) preferred surveillance, and the remaining 38% (n=197) preferred surgery. After adjusting for potential confounders, participants who expressed "worry" or "extreme worry" about the malignancy risk of IPMN had significantly lower risk thresholds than participants who were "not at all worried" (Coefficient -12, 95%CI -21 to -2, P=0.015 and Coefficient -18, 95%CI -29 to -8, P<0.001, respectively).

Conclusions: Participants varied in treatment preference and risk threshold of incidentally identified IPMNs. Given the uncertainty in estimating the true malignant potential of IPMNs, a better understanding of a patient's risk threshold, as influenced by patient concern about malignancy, will help inform the shared decision-making process.