title: Late rectal toxicity determined by dose-volume parameters in computed tomography-based brachytherapy for locally advanced cervical cancer.
abstract: The aim of this study was to observe the relationship between dose-volume histogram (DVH) parameters and rectal late side effects (LSE) in computed tomography (CT)-based brachytherapy (BT) for patients with locally advanced cervical cancer. In total, 144 cervical cancer patients received external beam radiotherapy and CT-based BT. The data from 111 survival cases with pelvic local control (LC) were used to analyze the relationship between DVH parameters and rectal LSE. The total doses, manifesting 2, 1, and 0.1 cm(3) (D2cc , D1cc , and D0.1cc ) of the rectum, and D90 for high-risk clinical target volume (HR CTV) were computed and normalized to 2 Gy fractions (EQD2) using a linear-quadratic model. The rectal LSE were evaluated by the late effects in normal tissues-subjective, objective, management, and analytic (LENT-SOMA) scale. A dose-response relationship was evaluated by probit analyses. For all patients, the total rate of rectal LSE was 56%, and the rate of ≥Grade 2 LSE was 27.4%. For the 111 survival cases with pelvic LC, the total mean for D2cc was 71.23 ± 5.54 Gy for the rectum, and the D2cc , D1cc , and D0.1cc values for Grades 2 and 3 were higher than those for Grades 0 and 1. In addition, the number of complications increased, and the complications became more severe as the dose increased, with a dose of 73.5 Gy resulting in a 10% probability of ≥Grade 3 LSE. In conclusion, DVH parameters could predict the incidence and grades of rectal LSE in CT-based BT. D2cc showed an excellent predictive value, and 73.5 Gy for D2cc of the rectum might be considered as an alternative dose limit.
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Yong-Chun
authors.initials: YC
authors.lastname: Zhou
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Zhao
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Xiao-Huan
authors.initials: XH
authors.lastname: Sun
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Jun-Yue
authors.initials: JY
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Li-Chun
authors.initials: LC
authors.lastname: Wei
authors.affiliation: Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China.
authors.forename: Mei
authors.initials: M
authors.lastname: Shi
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D008875:Middle Aged; D011879:Radiotherapy Dosage; D012007:Rectum / Q000528:radiation effects*; D016019:Survival Analysis; D014055:Tomography, Emission-Computed / Q000379:methods*; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000473:pathology / Q000532:radiotherapy*
keywords: Computed tomography-based brachytherapy; dose-volume histogram parameters; late side effects; locally advanced cervical cancer; rectum