Key Clinical Trials in Breast Imaging and Oncology
Z0011 — ACOSOG Surgical Trial
Full name: American College of Surgeons Oncology Group Z0011
Question
In T1-T2 breast cancer with 1–2 positive sentinel lymph nodes, is ALND required?
Findings
ALND did NOT significantly affect OS or DFS compared to SLND alone in patients with:
- Clinical T1-T2 breast cancer
- 1–2 positive SLNs without capsular extension
- Treated with lumpectomy + adjuvant systemic therapy + tangential-field whole-breast radiation therapy
Exclusions from Z0011
- Stage T3 tumors
- Clinically positive lymph nodes
- ≥ 3 positive sentinel lymph nodes
- Gross extranodal tumor extension
- Patients undergoing mastectomy
- Patients receiving neoadjuvant chemotherapy
- Patients receiving partial-breast radiation therapy
Complications of ALND vs. SLND in Z0011
- Wound infections, axillary seromas, paresthesias: 70% ALND vs. 25% SLND
- Lymphedema: significantly more common with ALND (by subjective report)
Board Pearl
Z0011 showed ALND is NOT required in T1-T2 with 1–2 positive SLNs if the patient gets lumpectomy + WBI + systemic therapy. This dramatically reduced the rate of routine ALND.
Z1071 — ACOSOG Surgical Trial
Question: After neoadjuvant chemotherapy (NAC) in cN1 patients, can SLN surgery replace ALND?
Findings
- Among women with cN1 breast cancer receiving NAC:
- FNR with ≥ 2 SLNs examined: 12.6% (90% BCI: 9.85–16.05%)
- This exceeds the prespecified acceptability threshold of 10%
- Dual-agent mapping (blue dye + technetium) and recovery of > 2 SLNs → lower likelihood of false-negative SLN
Conclusion
SLN surgery is NOT an adequate alternative to ALND in cN1 patients after NAC given the FNR > 10%.
Board Pearl
Z1071 differs from Z0011: Z1071 evaluates NAC + cN1 patients. FNR of 12.6% exceeds the 10% threshold, meaning ALND is still needed in cN1 NAC patients.
ACRIN 6666 — Screening Ultrasound Trial
Full name: ACRIN 6666 — Breast Cancer Screening in Women with Dense Breasts
Key Findings
- Incremental cancer detection with supplemental whole-breast US: 2–3 per 1,000 (in high-risk, dense-breast population)
- PPV3 markedly low: 6–7%
- ACRIN found slightly higher cancer numbers but population was higher risk
- Recall rate: approximately 2× screening mammography
- Biopsy rate: approximately 3× screening mammography
Choosing Wisely — 4 Low-Value Breast Cancer Treatments
Identified by: ACS (American College of Surgeons) + SSO (Society for Surgical Oncology) + ASBS (American Society of Breast Surgeons)
- ALND for limited nodal disease (lumpectomy + radiotherapy patients)
- Lumpectomy re-excision for close but negative margins for invasive cancer
- Contralateral prophylactic mastectomy (CPM) in average-risk women with unilateral cancer
- SLNB in clinically node-negative women ≥ 70 years old with hormone receptor-positive (HR+) cancer
Key Numbers Summary
| Trial/Study | Key Number |
|---|---|
| Z0011 | ALND ≠ improved OS in T1-T2 with 1–2 positive SLNs (lumpectomy + WBI) |
| Z0011 | ALND complications: 70% vs 25% SLND |
| Z1071 | FNR after NAC in cN1: 12.6% (exceeds 10% threshold) |
| ACRIN 6666 | Incremental detection: 2–3/1000; PPV3: 6–7% |
| SLNB accuracy | Overall accuracy: 98.2%; FNR: 5.8% |
| Skip metastases | 2.6% overall; 7.2% in biopsy-proven mets |
| Contralateral cancer detection | Mammo: 0.1–2%; MRI: 3–5% |
| Additional ipsilateral cancer | MRI detects in 10–25% |