Simulation analysis of optimized brachytherapy for uterine cervical cancer: Can we select the best brachytherapy modality depending on tumor size?

Ken Yoshida; Hideya Yamazaki; Tadayuki Kotsuma; Tadashi Takenaka; Mari Mikami Ueda; Shunsuke Miyake; Yutaka Tsujimoto; Koji Masui; Yasuo Yoshioka; Iori Sumida; Yasuo Uesugi; Taiju Shimbo; Nobuhiko Yoshikawa; Hiroto Yoshioka; Eiichi Tanaka; Yoshifumi Narumi

doi:10.1016/j.brachy.2015.10.002

Simulation analysis of optimized brachytherapy for uterine cervical cancer: Can we select the best brachytherapy modality depending on tumor size?

Brachytherapy. 2016 Jan-Feb;15(1):57-64. doi: 10.1016/j.brachy.2015.10.002. Epub 2015 Nov 21.

Authors

Affiliations

¹ Department of Radiation Oncology, Osaka Medical College, Takatsuki, Osaka, Japan. Electronic address: rad113@poh.osaka-med.ac.jp.
² Department of Radiology, Kyoto Prefectural University of Medicine, Kyoto, Kyoto, Japan.
³ Department of Radiation Oncology, National Hospital Organization Osaka National Hospital, Osaka, Osaka, Japan.
⁴ Department of Radiology, National Hospital Organization Himeji Medical Center, Himeji, Hyogo, Japan.
⁵ Department of Radiology, National Hospital Organization Osaka National Hospital, Osaka, Osaka, Japan.
⁶ Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
⁷ Department of Radiation Oncology, Osaka Medical College, Takatsuki, Osaka, Japan.
⁸ Department of Radiology, Osaka Medical College, Takatsuki, Osaka, Japan.

PMID: 26612700
DOI: 10.1016/j.brachy.2015.10.002

Abstract

Purpose: To choose the optimal brachytherapeutic modality for uterine cervical cancer, we performed simulation analysis.

Methods and materials: For each high-risk clinical target volume (HR CTV), we compared four modalities [classical conventional intracavitary brachytherapy (ConvICBT), Image-guided ICBT (IGICBT), intracavitary/interstitial brachytherapy (ICISBT), and interstitial brachytherapy (ISBT) with perineal approach] using dose-volume histograms using eight sizes of HR CTV (2 × 2 × 2 cm to 7 × 4 × 4 cm) and organs at risk model.

Results: In ConvICBT, the doses covered 90% of the HR CTV [D90(HR CTV)] decreased from 197% prescribed dose (PD) for the HR CTV size (2 × 2 × 2 cm) to 73% PD for 5 × 4 × 4 cm, whereas the other three modalities could achieve 100% PD for all HR CTV sizes. The minimum doses received by the maximally irradiated 2-cm(3) volumes for organs at risks of IGICBT demonstrated lower values than those of ConvICBT for the HR CTV size of 4 × 3 × 3 cm or smaller. ICISBT demonstrated lower values than those of IGICBT for 4 × 3 × 3 cm or larger. ISBT demonstrated lowest values for 5 × 4 × 4 cm or larger.

Conclusions: HR CTV size of 4 × 3 × 3 cm seems to be a threshold volume in this simulation analysis, and IGICBT is a better choice for smaller HR CTV than the threshold volume. On larger HR CTV, ICISBT or ISBT is the better choice.

Keywords: Brachytherapy; Dose-volume histograms; Simulation analysis; Uterine cervical cancer.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Brachytherapy / methods*
Computer Simulation*
Female
Humans
Models, Theoretical
Organs at Risk*
Radiotherapy Dosage
Radiotherapy Planning, Computer-Assisted*
Radiotherapy, Image-Guided / methods
Tumor Burden*
Uterine Cervical Neoplasms / pathology*
Uterine Cervical Neoplasms / radiotherapy*