Breast
Only breast data today: an APBI patient-selection update, not an efficacy readout.
GEC-ESTRO Breast Cancer Working Group APBI patient selection recommendations
TL;DRUpdated APBI selection criteria collapse to two groups (low-risk eligible, high-risk contraindicated), widening eligibility to pT1-2 ≤30mm, pN1mi, any histology.
The eligibility boundary moved, not the technique: pN1mi and multifocal disease within 2 cm are now inside the low-risk group, and the ceiling is 30 mm across all histologies. The 2010 intermediate tier is gone, so the contralateral question at consent is binary. BRCA 1-2 carriers are contraindicated regardless of age.
In a woman over 40 post-lumpectomy with a 25 mm pT2 pN1mi tumor and clear margins, this supports offering APBI where the 2010 criteria would not have; it does not extend to triple negative, BRCA carriers, or an unstaged axilla.
The eligibility boundary moved, not the technique: pN1mi and multifocal disease within 2 cm are now inside the low-risk group, with a 30 mm ceiling across all histologies. The intermediate tier is gone, so the APBI-vs-whole-breast conversation is binary. No dose, fractionation or target volume is specified in source.
Margin status is the surgical lever: a negative invasive margin qualifies, but DCIS requires ≥ 2 mm, so a close DCIS margin decides re-excision vs losing APBI eligibility. Unknown axillary status (pNx) is a contraindication, so skipping staging forecloses the option; pN1mi does not.
9 details
Evidence-based recommendation update from the GEC-ESTRO Breast Cancer Working Group. Systematic search 2010 to 2024 across PubMed, Medline, Scopus and Cochrane returned 618 articles, supplemented by reference lists, conference abstracts and book chapters. Ten prospective randomized trials and seven retrospective comparative studies with ≥ 5 yr median follow-up formed the evidence base.
Applies to pts after breast-conserving surgery being considered for partial breast irradiation. The low-risk group is age > 40 yr, unifocal or multifocal within 2 cm, pTis or T1-2 (≤ 30 mm), pN0 or pN1mi, all histology types, no EIC, no extensive LVI, negative invasive margins (≥ 2 mm for DCIS).
The document addresses who gets APBI, not how. No dose, fractionation, technique (brachytherapy vs external beam) or target-volume recommendation is given in the source text.
Two categories replace the prior scheme: low-risk good candidates and high-risk contraindicated. Contraindications are BRCA 1-2 mutation, age < 40 yr, positive invasive margins (< 2 mm for DCIS), multicentric or > 30 mm disease, triple negative, EIC positive, extensive LVI, and ≥ pN1a or pNx.
| Criterion | Low risk (APBI suitable) | High risk (APBI contraindicated) |
|---|---|---|
| Age | > 40 years | < 40 years |
| Germline | not specified | BRCA 1-2 mutation |
| T stage / size | pTis, T1-2 (≤ 30 mm) | > 30 mm |
| Focality | unifocal or multifocal within 2 cm | multicentric |
| Nodal status | pN0 or pN1mi | ≥ pN1a, or unknown axilla (pNx) |
| Histology | all histology types | triple negative |
| EIC | absent | EIC positive |
| LVI | no extensive LVI | extensive LVI |
| Margins | negative for invasive (≥ 2 mm for DCIS) | positive for invasive (< 2 mm for DCIS) |
Recommendation strength per criterion is not reported in the source text, so a reader cannot tell which thresholds rest on randomized data and which on panel opinion. The evidence base mixes ten randomized trials with seven retrospective comparative series without stated weighting.
The direction of travel is eligibility expansion: the authors state the 2010 criteria can be significantly expanded so more pts may receive APBI in routine practice. What the document does not settle is whether the widened boundary holds at the margins it moved most, node-micrometastatic and multifocal disease, where the randomized APBI trials enrolled few pts.
- IBTR outcomes for APBI in pN1mi disease
- Whether multifocal disease within 2 cm carries equivalent in-field control
- Whether triple negative warrants blanket APBI exclusion