Eur Radiol. 2025 Jun 25. doi: 10.1007/s00330-025-11772-1. Online ahead of print.
ABSTRACT
OBJECTIVES: Rejection is the leading cause of graft failure, and its diagnosis remains a challenge. Elastography and dynamic contrast-enhanced ultrasound (DCE-US) are novel non-invasive techniques for quantifying tissue elasticity and perfusion. Their role in pancreas graft rejection has not yet been defined.
MATERIALS AND METHODS: From October 16 to January 20, all pancreas transplantations performed at our institution were prospectively studied with elastography and DCE-US at 1 week, 3 weeks, and 12 months post-transplantation. Surveillance biopsies were performed at 3 weeks and 12 months. Elastography and DCE-US were also conducted in all requested biopsies during this period (regardless of the date of transplantation). Patients were categorized according to the biopsy result: normal/rejection. Grafts with other complications were excluded. Cut-off values were established.
RESULTS: One hundred twenty-one elastography and 127 DCE-US in 56 patients were included. All parameters showed a high dispersion during the first 90 days post-transplantation. After this period, the rejection group presented higher stiffness (0.97 vs 1.46 m/s, p < 0.001) and lower perfusion. The optimal cut-off value for elastography was 1.27 m/s (AUC 0.80), and for DCE-US were: peak enhancement 601 a.u. (AUC 0.67), wash-in AUC 2748 a.u. (AUC 0.70), wash-in rate 118 a.u. (AUC 0.65), wash-in perfusion index 369 a.u. (AUC 0.67), wash-out AUC 5181 a.u. (AUC 0.69) and total AUC 6388 a.u. (AUC 0.68). A combined predictive score showed that alteration of elastography and DCE-US was associated with a 23.2-fold probability of rejection.
CONCLUSION: After the first 90 days post-transplantation, pancreas graft rejection is associated with higher stiffness and lower graft perfusion.
KEY POINTS: Question Pancreas graft rejection remains a clinical challenge, as there are currently no reliable non-invasive tests for its diagnosis. Findings After the first 90 days post-transplantation, elastography and DCE-US show higher stiffness and lower pancreas graft perfusion in the presence of rejection. Clinical relevance These non-invasive tools, which can be easily integrated into daily routine practice, may be useful in identifying grafts at higher risk of rejection, allowing closer follow-up or early biopsy to establish early rejection treatment, improving graft and patient survival.
PMID:40560414 | DOI:10.1007/s00330-025-11772-1
