Radiation doses of medical radiation workers performing low-dose-rate brachytherapy with 198Au grains and 192Ir pins for patients with oral cancers

Abstract

Objectives

Low-dose-rate brachytherapy (LDR-BT) with ¹⁹⁸Au grains and ¹⁹²Ir pins is an essential treatment option for oral cancer due to its high rate of local control and low invasiveness. However, the radiation exposure of medical radiation workers is concerning. Thus, we aimed to determine the radiation dose delivered to medical radiation workers during LDR-BT using ¹⁹⁸Au grains and ¹⁹²Ir pins for oral cancer.

Methods

Thirty-two patients with oral cancer underwent ¹⁹⁸Au grain interstitial LDR-BT between June 2016 and May 2023, and 23 patients with tongue cancer underwent ¹⁹²Ir pin interstitial LDR-BT between March 2015 and November 2017 at our hospital. Dosimetry was performed by attaching a dosimeter to the chest pocket of the operator and assistant during ¹⁹⁸Au grain or ¹⁹²Ir pin LDR-BT. Since the operator also loads ¹⁹⁸Au grains into the implantation device, the operator’s radiation dose includes the dose received during this preparation.

Results

Mean radiation doses of the operators with ¹⁹⁸Au grain and ¹⁹²Ir pin LDR-BT were 165.8 and 211.2 μSv, respectively. Statistically significant differences between the radioactive sources of ¹⁹⁸Au grain and ¹⁹²Ir pin LDR-BT were observed (p = 0.0459). The mean radiation doses of the assistants with ¹⁹⁸Au grain and ¹⁹²Ir pin LDR-BT were 92.0 and 162.0 μSv, respectively. Statistically significant differences were observed between the radioactive sources of ¹⁹⁸Au grains and ¹⁹²Ir pin LDR-BT (p = 0.0003).

Conclusions

Regarding radioactive source differences, ¹⁹²Ir pin LDR-BT resulted in higher doses delivered to medical radiation workers than ¹⁹⁸Au grain LDR-BT.