- Partial breast irradiation (PBI) in women with early breast cancer is associated with greater 5-year risk of local recurrence and greater toxicity than whole breast irradiation (WBI), but PBI carries reduced risk of death without tumor recurrence.
Why this matters
- While WBI remains the standard of care, PBI using external beam radiation therapy may be optimal for smaller, hormone receptor-positive tumors without nodal involvement.
- Meta-analysis of 9 randomized controlled trials (n=14,514) after search of MEDLINE.
- Funding: None disclosed.
- PBI (vs WBI) was associated with 5-year:
- Higher risk of local recurrence (OR, 1.69; P<.001>
- Greater toxicity (fat necrosis: OR, 1.72; P=.002; and marginally more breast pain: OR, 1.17; P=.07);
- Lower odds of death without tumor recurrence (OR, 0.55; P<.001>
- Marginally improved OS (OR, 0.84; P=.06); and
- Marginally worse cosmetic outcome (OR, 1.23; P=.06).
- Nodal involvement (vs non-nodal) was associated with greater odds of local recurrence (P=.027); and
- Larger tumor size (vs smaller size) was associated with less improvement from death without tumor recurrence (P=.011) and shorter OS (P=.019).
- Small number of trials.
- Only 1 database searched.
- Longer duration than 5 years may be needed.