The American Society of Breast Surgeons
Accelerated Partial Breast Irradiation
This guideline holds 8 recommendations, 61 references and 1 table.
Summary
Partial breast irradiation (PBI) delivers radiation locally to the lumpectomy cavity. Accelerated PBI (APBI) condenses treatment from 5-6 weeks to a week or less. This guide helps breast surgeons interpret multiple guidelines on APBI and apply them in clinical practice, noting comparable recurrence rates, reduced toxicity, and improved convenience compared to whole breast irradiation (WBI).
Key takeaways
Accelerated Partial Breast Irradiation (APBI) condenses radiation treatment time and delivers targeted radiation, showing comparable long-term local control to whole breast irradiation (WBI) for appropriately selected patients.
Appropriate candidates generally include patients aged 40 and older, with tumors ≤ 3cm, negative nodal status, and negative margins.
APBI is contraindicated for patients with known BRCA1 or BRCA2 germline mutations.
Shared decision-making and multidisciplinary team discussions are essential when applying guidelines to individual patients, especially for complex cases like omitted sentinel lymph node biopsy or prior radiation.
What is new in this version
Updates the prior 2018 ASBrS resource guide by incorporating long-term results from randomized clinical trials (over 10,000 patients) comparing PBI with WBI, and aligns with recent clinical guideline updates from ASTRO and ABS.
Recommendations
Recommendations
Age: Minimum of 40 years
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
Histology: All invasive subtypes (recognizing ASTRO conditionally does not recommend APBI in lobular histology due to poor representation, while ABS recommends APBI in all invasive subtypes) and Ductal carcinoma in situ (DCIS).
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
Total tumor size (invasive and DCIS): less than or equal to 3 cm in size
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
T Size: Tis, T1, T2 (≤ 3 cm)
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
Margins: No tumor on ink for invasive tumors and invasive tumors with associated DCIS; ≥ 2mm for DCIS.
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
Nodal Status: Negative. Omission of sentinel lymph node biopsy may affect candidacy; multidisciplinary discussion is recommended.
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
Other Factors: Multifocal disease allowed if combined area is ≤3cm. Estrogen receptor positive or negative allowed. Use caution with lymphovascular invasion (LVI). Do not use APBI if BRCA or other high-risk genetic mutation is present. Repeat breast-conserving surgery with APBI may be considered for unifocal ipsilateral recurrences <3cm in selected patients.
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
Patient selection and counseling should be performed in a multidisciplinary fashion with collaboration between the treating surgeon and the treating radiation oncologist.
Population: Patients with breast cancer considering APBIWhen: Breast Cancer
More in oncology
- SEMERGEN Position Statement on the management of the Oncologic Patient: Comprehensive Approach to Cardiotoxicity in Primary CareSEMERGEN · 2026
- Updated clinical practice guidelines for the management of adult diffuse gliomasEuropean Respiratory Society · 2026
- International guidelines for the delineation of the postoperative clinical target volumes (CTV) for parotid and submandibular gland cancers
