Effectiveness of Spacers in Brachytherapy With¹⁹⁸Au Grains for Patients With Buccal Mucosa Cancer

Background/Aim: The aim of this study was to investigate the use of spacers and their efficacy in brachytherapy with ¹⁹⁸Au grains for buccal mucosa cancer. Patients and Methods: Sixteen patients with squamous cell carcinoma of the buccal mucosa who were treated with ¹⁹⁸Au grain brachytherapy were included. The distance between ¹⁹⁸Au grains, distance between ¹⁹⁸Au grains and the maxilla or mandible, and the maximum dose/cc to the jawbone (D1cc) with and without a spacer was investigated in three out of 16 patients. Results: The median distance between ¹⁹⁸Au grains without and with a spacer was 7.4 and 10.7 mm, respectively; this was significantly different. The median distance between ¹⁹⁸Au grains and the maxilla without and with a spacer was 10.3 and 18.5 mm, respectively; again this was significantly different. The median distance between ¹⁹⁸Au grains and the mandible without and with a spacer was 8.6 and 17.3 mm, respectively; the difference was significant. The D1cc to the maxilla without and with a spacer were 14.9, 68.7, and 51.8 Gy and 7.5, 21.2, and 40.7 Gy in cases 1, 2, and 3, respectively. The D1cc to the mandible without and with a spacer were 27.5, 68.7, and 85.8 Gy and 11.3, 53.6, and 64.9 Gy in cases 1, 2, and 3, respectively. No osteoradionecrosis of the jaw bones was observed in any case. Conclusion: The spacer enabled maintenance of the distance between ¹⁹⁸Au grains, and between ¹⁹⁸Au grains and the jawbone. In buccal mucosa cancer, using a spacer in brachytherapy with ¹⁹⁸Au grains appears to reduce jawbone complications.