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

Objectives: Low-dose-rate brachytherapy (LDR-BT) with Au grains and Ir 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 grains and Ir pins for oral cancer.

Methods: Thirty-two patients with oral cancer underwent Au grain interstitial LDR-BT between June 2016 and May 2023, and 23 patients with tongue cancer underwent Ir 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 grain or Ir pin LDR-BT. Since the operator also loads Au 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 grain and Ir pin LDR-BT were 165.8 and 211.2 μSv, respectively. Statistically significant differences between the radioactive sources of Au grain and Ir pin LDR-BT were observed (p = 0.0459). The mean radiation doses of the assistants with Au grain and Ir pin LDR-BT were 92.0 and 162.0 μSv, respectively. Statistically significant differences were observed between the radioactive sources of Au grains and Ir pin LDR-BT (p = 0.0003).

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