Are liver metastases from uveal melanoma a clinical indication for dynamic PET? A comparison of Patlak parametric imaging with standard and delayed static SUV imaging using long axial field-of-view PET/CT.

purposeDespite decades of technical development, dynamic PET and parametric imaging have not yet achieved widespread clinical implementation in oncology, largely due to technical complexity and the limited number of clinical scenarios in which clear additional value over static imaging has been demonstrated. We hypothesized that liver metastases from uveal melanoma-a tumor entity often characterized by low tumor-to-background contrast on static imaging- may represent a particularly promising application for dynamic PET imaging. Accordingly, we aimed to determine whether dynamic Patlak parametric imaging improves lesion detectability and conspicuity compared with standard (50-60 min) and delayed (70-85 min) static standardized uptake value (SUV) imaging. MATERIAL AND

methodsTwenty-six patients with uveal melanoma and a total of 126 tumor lesions, including 58 liver metastases and 68 other metastases, were prospectively enrolled. All patients underwent a 60 min dynamic data acquisition (skull to upper thigh) followed by whole-body [

resultsNo significant differences were observed among the three imaging approaches with respect to the total number of detected tumor lesions. However, one discordant finding was noted: a true-positive liver metastasis was identified on Patlak K

conclusionsAlthough lesion detection rates were not significantly increased, dynamic acquisition with Patlak parametric imaging provided a robust and less timing-dependent method to enhance tumor-to-background contrast compared with static SUV imaging and may yield discordant findings with additional clinical value in selected cases. Overall, Patlak imaging may therefore represent a complementary contrast-optimization approach for evaluating liver metastases from uveal melanoma.