[10p-E204-1~13] 2.4 Life Sciences, Medical applications, Space and Earth Environment, Radiation Education

1:30 PM - 1:45 PM JST(4:30 AM - 4:45 AM UTC)

[10p-E204-1] Washout Analysis of Particle Beam–Induced Positron-Emitting Nuclides: Application to Tumor Diagnosis

〇Chie Toramatsu¹, Wakizaka Hidekatsu¹, tashima Hideaki¹, Sudo Hitomi¹, Akamatsu Go¹, Ishikawa Taiyo¹, Han Gyu Kang¹, Seki Chie¹, Kanno Iwao¹, Yamaya Taiga¹ (1.QST)

Keywords:

PET,particle therapy,hypoxia tracer

Tumor vascular status provides important information for estimating hypoxic/angiogenesis regions. In radiotherapy, monitoring these regions during the treatment course is desirable; however, repeated examinations using PET tracers are difficult in clinical practice. On the other hand, in carbon-ion irradiation experiments using tumor-bearing rats, we developed an analytical method to generate washout rate maps of beta⁺-emitting nuclides and found that these maps correlate with the uptake of hypoxia PET tracers. In this study, we report on the clinical application of this analytical method established through basic research. An OpenPET prototype system was installed in the fixed beam port room of HIMAC, and the in vivo distribution of beta⁺-emitting nuclides generated by carbon-ion therapy was imaged immediately after irradiation in a patient with head and neck cancer (jRCTs032220746). Specifically, PET imaging was performed for 10 minutes after irradiation, and a voxel-wise kinetic modeling approach was applied to calculate washout rate maps. We successfully demonstrated an application of the washout rate modeling method in a clinical case. Changes in washout rate maps may reflect tumor vascular status, and future studies will investigate their relationship with treatment outcomes.