Dose-Escalated Radiation Therapy as Primary Treatment for Residual Bladder Cancer After Transurethral Resection

Yu-Chen Chang; Yao-Yu Wu; Din-Li Tsan; Wing-Keen Yap; Kan-Hsin Fan; Joseph Tung-Chieh Chang; Eric Yi-Liang Shen

doi:10.1016/j.adro.2023.101302

Dose-Escalated Radiation Therapy as Primary Treatment for Residual Bladder Cancer After Transurethral Resection

Adv Radiat Oncol. 2024 Jan 12;9(1):101302. doi: 10.1016/j.adro.2023.101302. eCollection 2024 Jan.

Authors

Yu-Chen Chang¹, Yao-Yu Wu¹, Din-Li Tsan^{1

2}, Wing-Keen Yap¹, Kan-Hsin Fan³, Joseph Tung-Chieh Chang¹, Eric Yi-Liang Shen^{1

4

5}

Affiliations

¹ Department of Radiation Oncology and Proton Therapy Center, Linkou Chang Gung Memorial Hospital and Chang Gung University, Taoyuan City, Taiwan.
² Department of Radiation Oncology, Chang Gung Memorial Hospital, Keelung, Taiwan.
³ Department of Radiation Oncology, New Taipei Municipal Tucheng Hospital, New Taipei City, Taiwan.
⁴ Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, United Kingdom.
⁵ Clinical Metabolomics Core Lab, Chang Gung Memorial Hospital at Linkou and Chang Gung University, Taoyuan, Taiwan.

Abstract

Purpose: The aim of this study was to determine whether escalating the local radiation dose can improve the outcome of residual bladder cancer after transurethral resection of bladder tumor without increasing treatment-related toxicity.

Methods and materials: The treatment plans and medical records of patients with bladder cancer treated with curative-intent radiation therapy between 2008 and 2020 were reviewed. Those who had residual tumors in the computed tomography simulation images were included. A cumulative radiation dose higher than 6600 cGy was defined as dose escalation. The effect of dose escalation on 3-year locoregional control, progression-free survival, and overall survival was evaluated.

Results: A total of 149 patients with residual tumors were identified. The median follow-up period was 27.5 months. Among them, 51 patients received an escalated radiation dose, and 98 received a standard dose in the residual tumor area. Patients in the dose-escalation group had higher 3-year locoregional control (65.6% vs 27.8%; P < .001) and progression-free survival (42.6% vs 18.2%; P < .001) than the standard-dose group. Overall survival also showed a trend favoring the dose-escalation group (54.9% vs 36.2%; P = .059). In the multivariate analyses, the differences between the dose-escalation and standard-dose groups were significant in terms of locoregional control (hazard ratio, 0.32; CI, 0.18-0.59; P = <.001) and progression-free survival (hazard ratio, 0.51; CI, 0.32-0.82; P = .005). There was no statistical difference in acute and chronic treatment-related toxicities between the 2 groups.

Conclusions: The outcome of residual bladder cancer after transurethral resection of bladder tumor could be improved by dose-escalated radiation therapy.