Feasibility and Safety of the "One-Week Breast Radiation Therapy" Program

Area of Science:

• Radiation Oncology
• Breast Cancer Treatment
• Clinical Workflow Optimization

Background:

• Established FAST-Forward and UK-FAST trials confirm safety and efficacy of five-fraction breast adjuvant radiation therapy (RT).
• The COVID-19 pandemic necessitated innovative approaches to manage increased treatment burdens.
• "One-Week Breast RT" was implemented to deliver five-fraction whole breast RT within a compressed 5-day workflow.

Purpose of the Study:

• To demonstrate the feasibility and safety of the innovative "One-Week Breast RT" program.
• To evaluate the cosmetic outcomes of patients undergoing this accelerated RT regimen.
• To assess the program's effectiveness in a real-world clinical setting.

Main Methods:

• A total of 120 early breast cancer patients received 26 Gy in five fractions over one week.
• Treatment utilized inverse planning with restricted optimization and systematic deep inspiration breath-hold (DIBH).
• Toxicity and cosmetic outcomes were prospectively assessed using Common Terminology Criteria for Adverse Events (CTCAE) v. 4.03 and Harvard scale.

Main Results:

• 93.3% of patients completed RT within the one-week timeframe.
• Most common acute toxicities included radiation dermatitis (72%), induration (35%), and edema (16%); all were mild (grade <3).
• Radiation dermatitis significantly decreased from end-RT to 6 months (71.7% vs 5.4%, P<0.001), with 94.1% reporting good or excellent cosmetic results at 6 months.

Conclusions:

• The "One-Week Breast RT" program is feasible and acutely safe in clinical practice.
• Favorable toxicity profiles and cosmetic outcomes are consistent with FAST-Forward trial findings.
• A prospective national cohort study is underway to further evaluate treatment burden reduction, safety, efficacy, and workflow efficiency with longer follow-up.