Effect of Hyaluronate Acid Injection on Dose-Volume Parameters in Brachytherapy for Cervical Cancer
Rei Kobayashi, Naoya Murakami, Takahito Chiba, Kae Okuma, Koji Inaba, Kana Takahashi, Tomoya Kaneda, Tairo Kashihara, Ayaka Takahashi, Yuri Shimizu, Yuko Nakayama, Tomoyasu Kato, Yoshinori Ito, Hiroshi Igaki
Abstract
PurposeHyaluronate gel has been injected as a spacer into the rectovaginal fossa and vesicouterine fossa during brachytherapy for patients with cervical cancer at our institution. The effect of hyaluronate gel injection (HGI) on dose-volume parameters was investigated in this study.Methods and MaterialsBetween July 2008 to January 2020, a total of 104 patients (non-HGI group: 52 patients; HGI group: 52 patients) who underwent curative radiation therapy for cervical cancer were selected. The total doses of external beam radiation therapy and brachytherapy for high-risk clinical target volume (CTVHR) D90, bladder D2cc, and rectal D2cc were converted to the equivalent dose in 2 Gy fractions (EQD2) and were analyzed for association with HGI.ResultsMedian CTVHR D90 (EQD2) in the non-HGI group was 76.0 Gy (63.7-99.5 Gy), and in the HGI group it was 79.4 Gy (52.6-97.5 Gy) (P = .017). The median bladder D2cc and rectal D2cc (EQD2) were 62.9 Gy and 56.0 Gy in the non-HGI group and 63.7 Gy and 54.8 Gy in the HGI group, which had no significant difference.ConclusionsIn cases with HGI, a significant CTVHR D90 dose increase was obtained with sufficient bladder and rectal doses suppression.