Exploring pancreatic variability in BRCA carriers vs. Non-Carriers: A diffusion tensor MRI study

Pancreatic ductal adenocarcinoma (PDAC) is a dismal disease, often diagnosed at advanced, unresectable stages. Early detection is critical to improve survival, but current imaging modalities are limited in detecting early stage malignancies. Diffusion tensor MRI (DT-MRI) has shown potential in identifying PDAC. This study confirms the feasibility of DT-MRI to measure pancreatic diffusion metrics and examines whether DT-MRI detects any differences in these metrics between high-risk genetic mutations carriers and controls.

Retrospective data analysis included 18 high-risk individuals with PDAC-predisposing mutations and 17 controls undergoing routine pancreatic MRI. Participants underwent standard MRI and DT-MRI (3T scanner, b-values 0-500 and 100-500 s/mm²), with clinical, demographic, and pathological data collected. Statistical analyses included Wilcoxon signed-rank tests, Mann-Whitney U-tests, and Benjamini-Hochberg corrections.

Among 35 participants (14 males, 21 females), the median ages were 51 for high-risk and 65 for controls (p = 0.0436, Welch's t-test). DTI metrics (λ₁, λ₂ and λ₃, apparent diffusion coefficient and fractional anisotropy) varied significantly between the two b-value pairs (p < 0.00001). However, these metrics and the λ₁, λ₂ and λ₃ ratios (medians 1.1, 1.4, 2.4, IQRs 0.11, 0.22, 0.76, respectively) showed no significant differences between the high-risk and control groups after correction. Yet, λ₁, λ₂ and λ₃ ratios showed IVIM-related directional variations, suggesting directional differences in capillary perfusion of the pancreas.

DT-MRI effectively measures diffusion coefficients and IVIM contributions in the pancreas. No significant differences were found between high-risk individuals and controls, therefore, the method supports adjunct, bias-free use in future pancreatic cancer screening studies.