LAUSR

Context: Recently, the dynamic jaw mode has been introduced in our radiation oncology center second in China. Many studies showed that dynamic jaw mode in helical tomotherapy (HT) has the potential to improve organs at risk avoidance. Aim: This study aimed to evaluate the plan quality and efficiency of dynamic jaw delivery compared to the regular HT delivery mode (fixed jaw mode) for cervical carcinoma. Settings and Design: Plan quality and efficiency were compared among the fixed jaw 2.5 cm mode, the dynamic jaw 2.5 cm mode, and the dynamic jaw 5.0 cm mode. Subjects and Methods: A total of 20 patients with cervical carcinoma were chosen to compare the plan quality and treatment efficiency using regular HT mode (fixed jaw 2.5 cm field width) and HT dynamic jaw mode with width 2.5 cm and 5.0 cm field width. The prescribed dose was 50.4 Gy in 28 fractions to planning target volume. Target coverage, homogeneity, conformity, sparing of organs at risk (OARs), monitor unit, and beam-on time were evaluated. Statistical Analysis Used: The statistical significance of any difference among plans assessed the two-sided paired t-test. The statistical analysis was conducted using SPSS 19.0 software. Results: For each of the 20 patients, the plans were clinically acceptable. The target coverage and sparing of most OARs were measured using the dynamic jaw. Conclusions: Cervical carcinoma should be treated with the dynamic jaw 2.5 cm mode. Considering the risk of long treatment time, the dynamic jaw 5.0 cm mode could be an option.