The impact of axillary ultrasound with biopsy in overtreatment of early breast cancer.

PURPOSE: (a) To compare the axillary tumor burden detected by fine-needle aspiration cytology (FNAC) versus sentinel lymph node biopsy (SLNB). (b) To evaluate the relationship between axillary tumor burden and the number of suspicious lymph nodes detected by axillary ultrasonography (US). (c) To calculate the false-positive and false-negative rates for FNAC in patients fulfilling ACOSOG Z0011 criteria. METHODS: Retrospective multicenter cross-sectional study of 355 pT1 breast cancers. SLNB and axillary lymph node dissection (ALND) were gold standards. Low axillary burden (≤2 positive lymph nodes); high burden (>2 positive lymph nodes). Patients ACOSOG Z0011: false-positive (positive FNAC+low burden), false-negative (negative FNAC+high burden). RESULTS: High axillary burden: in entire series 38.5% FNAC+ vs. 5.7% SLNB+ (p<0.0001). In subgroup fulfilling ACOSOG Z0011 criteria: 45.5% vs 6.7%, respectively (p<0.001). 61 positive axillary US. With 1 suspicious node on axillary US: 95.6% had ≤2 involved nodes (including pN0); with 2 suspicious nodes: 60% had >2 involved nodes. In ACOSOG Z0011 patients, with 1 suspicious node, 93.7% had ≤2 involved nodes. Of the 37 FNAC in ACOSOG Z0011patients: 54.5% false-positives for high burden; 3.8% false-negatives. CONCLUSIONS: FNAC-positive tumors have greater axillary burden, even in patients fulfilling ACOSOG Z0011 criteria. Using axillary US/FNAC to triage patients meeting Z0011 criteria may result in axillary overtreatment. The number of suspicious nodes seen in axillary US is related with the final axillary burden and should be taken into account when deciding to do FNAC in patients fulfilling ACOSOG Z0011 criteria.

The impact of preoperative axillary ultrasonography in T1 breast tumours.

OBJECTIVES: To (a) determine the diagnostic validity of axillary ultrasound (AUS) in pT1 tumours and whether fine-needle aspiration (FNA) improves its diagnostic performance, and (b) determine the negative predictive value (NPV) of AUS in a simulation environment (cutoff: two lymph nodes with macrometastases) in patients fulfilling American College of Surgeons Oncology Group (ACOSOG) Z0011 criteria. MATERIALS AND METHODS: This retrospective multicentre cross-sectional study analysed diagnostic accuracy in 355 pT1 breast cancers. All patients underwent AUS; visible nodes underwent FNA regardless of their AUS appearance. Sentinel node biopsy and axillary lymph node dissection (ALND) were gold standards. Data were analysed considering micrometastases 'positive' and considering micrometastases 'N negative'. The simulation environment included all patients fulfilling ACOSOG Z0011 criteria. RESULTS: Axillary involvement: 22.8 %; AUS sensitivity: 46.9 % (Nmic positive)/66.7 % (Nmic negative); AUS+FNA sensitivity: 52.6 % (pNmic positive)/72.0 % (pNmic negative). In the simulation environment, AUS had 75.0 % sensitivity, 88.9 % specificity and 99.2 % NPV. CONCLUSION: AUS has moderate sensitivity in T1 tumours. As ALND is unnecessary in micrometastases, considering micrometastases 'N negative' increases the practical impact of AUS. In patients fulfilling ACOSOG Z0011 criteria, AUS alone can predict cases unlikely to benefit from ALND. KEY POINTS: • AUS+FNA can predict axillary involvement, thus avoiding SNB. • Not all patients with axillary involvement need ALND. • Axillary tumour load determines axillary management. • AUS could classify patients according to axillary load.

Shear-wave elastography and immunohistochemical profiles in invasive breast cancer: evaluation of maximum and mean elasticity values.

PURPOSE: To evaluate the correlations of maximum stiffness (Emax) and mean stiffness (Emean) of invasive carcinomas on shear-wave elastography (SWE) with St. Gallen consensus tumor phenotypes. METHODS: We used an ultrasound system with SWE capabilities to prospectively study 190 women with 216 histologically confirmed invasive breast cancers. We obtained one elastogram for each lesion. We correlated Emax and Emean with tumor size, histologic type and grade, estrogen and progesterone receptors, HER2 expression, the Ki67 proliferation index, and the five St. Gallen molecular subtypes: luminal A, luminal B without HER2 overexpression (luminal B HER2-), luminal B with HER2 overexpression (luminal B HER2+), HER2, and triple negative. RESULTS: Lesions larger than 20 mm had significantly higher Emax (148.04 kPa) and Emean (118.32 kPa) (P=0.005) than smaller lesions. We found no statistically significant correlations between elasticity parameters and histologic type and grade or molecular subtypes, although tumors with HER2 overexpression regardless whether they expressed hormone receptors (luminal B HER2+ and HER2 phenotypes) and triple-negative tumors had lower Emax and Emean than the others. We assessed the B-mode ultrasound findings of the lesions with some of the Emax or Emean values less than or equal to 80 kPa; only four of these had ultrasound findings suggestive of a benign lesion (two with luminal A phenotype and two with HER2 phenotype). CONCLUSIONS: We were unable to demonstrate statistically significant differences among the subtypes of invasive tumors, although there appears to be a trend toward lower Emax and Emean in the aggressive phenotypes.