Purpose
To identify when, from the standpoint of relative risk, MRI-based pancreatic cancer screening may be effective in patients with a known or suspected genetic predisposition.
Methods
We developed a Markov model of pancreatic ductal adenocarcinoma (PDAC). The model was calibrated to National Cancer Institute Surveillance, Epidemiology and End Results registry data and informed by the published literature. A hypothetical screening strategy was evaluated in which all population individuals underwent one-time MRI screening at age 50. Screening outcomes for individuals with average PDAC risk (base case) were compared to those with increased risk, to assess for differential benefits in populations with a known or suspected genetic predisposition. Effects of varying key inputs, including MRI performance, surgical mortality, and screening age, were evaluated in sensitivity analysis.
Results
In the base case, screening resulted in a small number of cancer deaths averted (39/100,000 (men), 38/100,000 (women)) and a net decrease in life expectancy, driven by surgical deaths from false-positive results (-3 days (men), â4 days (women)). Life expectancy gains were achieved if individualsâ risk for PDAC exceeded 2.4Ă (men) or 2.7Ă (women) that of the general population. When relative risk increased further, for example to 30Ă that of the general population, averted cancer deaths and life expectancy gains increased substantially (1,219/100,000, 65 days (men) and 1,204/100,000, 71 days (women)). Results were additionally sensitive to MRI specificity and the surgical mortality rate.
Conclusions
Although PDAC screening with MRI for the entire population is not effective, individuals with even modestly increased risk may benefit.