Whole Versus Partial Bladder Radiation: Use of an Image-guided Hypofractionated IMRT Bladder-preservation Protocol

Area of Science:

• Oncology
• Radiation Oncology
• Urothelial Carcinoma Research

Background:

• Muscle-invasive bladder cancer (MIBC) requires effective treatment strategies.
• Definitive chemoradiation is an alternative to cystectomy for MIBC.
• Optimizing radiation techniques can improve outcomes and reduce toxicity.

Purpose of the Study:

• To evaluate the institutional experience with definitive chemoradiation for MIBC using whole bladder (WB) and partial bladder (PB) techniques.
• To compare local control, overall survival, and toxicity between WB and PB radiation in MIBC patients.
• To assess the impact of hypofractionation and image-guidance on treatment efficiency and cost.

Main Methods:

• Retrospective analysis of 26 MIBC patients treated between 2009-2012.
• Patients received either WB radiation (16 patients) or PB radiation with a tumor boost (10 patients).
• Radiation doses and fractionation schedules were detailed, with local control as the primary endpoint.

Main Results:

• Two-year freedom from local recurrence was 86% (PB 100%, WB 77%).
• Two-year overall survival was 55% (PB 70%, WB 48%).
• Toxicities were minimal, and hypofractionation reduced treatment time and costs by one third.

Conclusions:

• Image-guided, hypofractionated PB radiation achieves local control and survival similar to WB therapy in MIBC.
• PB radiation demonstrates a favorable toxicity profile and offers significant time and cost savings.
• Larger, multi-institutional studies are needed to validate these findings.