Accelerated partial breast irradiation trials: diversity in rationale and design

Area of Science:

• Radiation Oncology
• Surgical Oncology
• Clinical Trials

Background:

• Breast conservation surgery is often followed by radiotherapy.
• Accelerated partial breast irradiation (APBI) is an alternative to whole breast radiotherapy (WBRT).
• Current trials investigate various APBI techniques and dose schedules.

Purpose of the Study:

• To compare accelerated partial breast irradiation (APBI) with whole breast radiotherapy (WBRT).
• To evaluate the efficacy and safety of APBI based on different target volume concepts.
• To generate level I evidence for APBI in breast cancer treatment.

Main Methods:

• Seven ongoing randomized controlled trials.
• Comparison of APBI techniques (brachytherapy, teletherapy) versus WBRT.
• Focus on clinical and planning target volumes based on relapse patterns.

Main Results:

• Ongoing trials will provide level I evidence.
• Relapse patterns are not fully defined in existing literature.
• WBRT may reduce relapse in other breast quadrants.

Conclusions:

• Level I evidence is pending from ongoing trials.
• The biological model of relapse influences APBI target volume definitions.
• Long-term patient follow-up is essential for definitive results.