Incorporation of vaginal brachytherapy to external beam radiotherapy in adjuvant therapy for high-risk early-stage cervical cancer: A comparative study

Omar M Ragab; Shahil Mehta; David J Nusbaum; Muneaki Shimada; Laurie L Brunette; Lynda D Roman; Koji Matsuo

doi:10.1016/j.brachy.2021.09.006

Incorporation of vaginal brachytherapy to external beam radiotherapy in adjuvant therapy for high-risk early-stage cervical cancer: A comparative study

Brachytherapy. 2022 Mar-Apr;21(2):141-150. doi: 10.1016/j.brachy.2021.09.006. Epub 2021 Oct 29.

Authors

Omar M Ragab¹, Shahil Mehta¹, David J Nusbaum², Muneaki Shimada³, Laurie L Brunette⁴, Lynda D Roman⁵, Koji Matsuo⁶

Affiliations

¹ Department of Radiation Oncology, University of Southern California, Los Angeles, CA.
² Section of Urology, University of Chicago Medicine, Chicago, IL.
³ Department of Obstetrics and Gynecology, Tohoku University, School of Medicine, Miyagi, Japan.
⁴ Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Southern California, Los Angeles, CA.
⁵ Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Southern California, Los Angeles, CA; Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA.
⁶ Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Southern California, Los Angeles, CA; Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA. Electronic address: koji.matsuo@med.usc.edu.

PMID: 34756697
DOI: 10.1016/j.brachy.2021.09.006

Abstract

Purpose: To examine trends, characteristics, and outcomes related to addition of vaginal brachytherapy (VBT) to external beam radiotherapy (EBRT) for adjuvant radiotherapy in high-risk early-stage cervical cancer.

Methods and materials: This comparative study is a retrospective observational analysis of the National Cancer Institutes' Surveillance, Epidemiology, and End Results Program. Surgically treated women with stage T1-2 cervical cancer who had high-risk factors (nodal metastasis and/or parametrial invasion) and received adjuvant radiotherapy from 2000 to 2018 were examined. Propensity score inverse probability of treatment weighting was used to assess the survival estimates for addition of VBT use.

Results: Among 2470 women with high-risk factors receiving EBRT, 760 (30.8%) had additional VBT. During the study period, there was an increasing trend of VBT use from 27.4% to 36.1% (p< 0.001). In a multivariable analysis, year of diagnosis and high-risk tumor factors: parametrial involvement, large tumor size, and use of chemotherapy remained independent characteristics associated with VBT use (all, p< 0.05). In propensity score-weighted models, VBT use with EBRT and EBRT alone had comparable overall survival (5-year rates 73.8% vs. 77.4%, hazard ratio [HR] 1.07, 95% confidence interval [CI] 0.92-1.25). Nonsignificant association was also observed in squamous or nonsquamous tumors, young or old age, low or high nodal ratio, chemotherapy use, and simple or radical hysterectomy (all, p> 0.05). Lastly, the addition of VBT was not associated with cervical cancer-specific survival (subdistribution-HR 1.15, 95% CI 0.94-1.41).

Conclusions: Utilization of VBT with EBRT for adjuvant radiotherapy in high-risk early-stage cervical cancer is increasing in the United States. Addition of VBT was associated with neither overall survival nor cancer-specific survival.

Keywords: Adjuvant radiotherapy; Cervical cancer; High risk; Survival; Trend; Vaginal brachytherapy.

Publication types

Observational Study

MeSH terms

Brachytherapy* / methods
Endometrial Neoplasms* / pathology
Female
Humans
Neoplasm Staging
Radiotherapy, Adjuvant / methods
Retrospective Studies
United States / epidemiology
Uterine Cervical Neoplasms* / pathology
Uterine Cervical Neoplasms* / radiotherapy