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

Objectives Low-dose-rate brachytherapy (LDR-BT) with Au-198 grains and Ir-192 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 Au-198 grains and Ir-192 pins for oral cancer.Methods Thirty-two patients with oral cancer underwent Au-198 grain interstitial LDR-BT between June 2016 and May 2023, and 23 patients with tongue cancer underwent Ir-192 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 Au-198 grain or Ir-192 pin LDR-BT. Since the operator also loads Au-198 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 Au-198 grain and Ir-192 pin LDR-BT were 165.8 and 211.2 mu Sv, respectively. Statistically significant differences between the radioactive sources of 198Au grain and( 192)Ir pin LDR-BT were observed (p = 0.0459). The mean radiation doses of the assistants with Au-198 grain and 192Ir pin LDR-BT were 92.0 and 162.0 mu Sv, respectively. Statistically significant differences were observed between the radioactive sources of 198Au grains and Ir-192 pin LDR-BT (p = 0.0003).Conclusions Regarding radioactive source differences, Ir-192 pin LDR-BT resulted in higher doses delivered to medical radiation workers than Au-198 grain LDR-BT.