Experimental investigation of the characteristics of radioactive beams for heavy ion therapy

• DOI: 10.1002/mp.14177
• Publication Date: 2020-04-12T06:19:53Z
• Authors: Andrew Chacon; Benjamin James; Linh Tran; Susanna Guatelli; Lachlan Chartier; Dale Prokopvich; Daniel R. Franklin; Akram Mohammadi; Fumihiko Nishikido; Yuma Iwao; Go Akamatsu; Sodai Takyu; Hideaki Tashima; Taiga Yamaya; Katia Parodi; Anatoly Rosenfeld; Mitra Safavi‐Naeini
• Keywords: Relative biological effectiveness

Purpose This work has two related objectives. The first is to estimate the relative biological effectiveness of radioactive heavy ion beams based on experimental measurements, and compare these corresponding stable isotopes determine whether they are therapeutically equivalent. second aim quantitatively quality images acquired postirradiation using an in‐beam whole‐body positron emission tomography scanner for range verification assurance. Methods energy deposited by monoenergetic C at 350 MeV/u, O 250 430 MeV/u was measured a cruciform transmission ionization chamber in water phantom Heavy Ion Medical Accelerator Chiba (HIMAC), Japan. Dose‐mean lineal various depths along path each beam silicon‐on‐insulator mushroom microdosimeter. Using modified microdosimetric kinetic model, 10% survival fraction evaluated compared that ions beam. Finally, distributions annihilations resulting from decay positron‐emitting nuclei were gelatin HIMAC. depth maximum positron‐annihilation density with dose deposition signal‐to‐background ratios calculated over 5 20 min phantom. Results In entrance region, 1.2 ± 0.1 both beams, while it 1.4 1.3 0.1, respectively. At Bragg peak, 2.7 0.4 2.9 C, 2.8 0.4, tail could only be carbon; 1.6 0.2 1.5 Positron obtained targets irradiated exhibit markedly improved those nonradioactive 5‐fold 11‐fold increases values difference between annihilation 2.4 0.8 mm −5.6 0.9 vs −6.6 O. Conclusions found within 95% confidence interval RBEs estimated their across regions which evaluated. Furthermore, given dose, produce much better O, particular regard estimating location peak.