Radiation Therapy for Bladder Cancer: An ASTRO Clinical Practice Guideline

This guideline provides evidence-based recommendations addressing the indications for radiation therapy (RT) for bladder cancer in a variety of clinical settings, ranging from patients with localized disease to metastatic and symptomatic disease.

The American Society for Radiation Oncology convened a task force to address 4 key questions: (1) indications for bladder preservation with curative-intent RT, with or without systemic therapy, for patients with nonmetastatic bladder cancer; (2) appropriate RT techniques and dose-fractionation regimens for patients with intact, localized or node-positive bladder cancer; (3) indications, appropriate RT techniques, and dose-fractionation regimens for postoperative RT, with or without systemic therapy; and (4) indications and appropriate dose-fractionation regimens for RT to the bladder or sites of metastases for patients with metastatic or symptomatic bladder cancer being treated with noncurative intent. Recommendations are based on a systematic literature review and were created using a predefined consensus-based methodology with a system for grading evidence quality and recommendation strength.

Multidisciplinary evaluation is encouraged for all patients. For select patients with cT2-4aN0M0 muscle-invasive bladder cancer, trimodal therapy (TMT) is an alternative to radical cystectomy. Concurrent radiosensitizing systemic therapy is recommended with TMT; neoadjuvant or induction systemic therapy is recommended for patients at higher risk of distant progression. RT to the whole bladder at full dose, or reduced dose to uninvolved bladder with a partial tumor boost, is recommended; elective nodal RT is conditionally recommended based on tumor characteristics. For patients with urothelial carcinoma who have (y)pT3-4 or (y)pN+ disease or positive margins postcystectomy, adjuvant RT is conditionally recommended for locoregional control. Intensity modulated RT with daily image guidance is recommended; target coverage goals and normal tissue dose guidance are provided. For patients with high-burden metastatic and locally symptomatic disease, or locoregional disease managed with noncurative intent, bladder-directed RT is recommended for local control and/or palliation.

These evidence-based recommendations guide clinical practice on the use of RT for bladder cancer. Future studies will further refine the indications and role of RT in the management of these patients.