Could axillary clearance be avoided in clinically node-negative breast cancer patients with positive nodes diagnosed by ultrasound guided biopsy in the post-ACOSOG Z0011 era?

Positive predictive value of axillary lymph node cortical thickness and nodal, clinical, and tumor characteristics in newly diagnosed breast cancer patients

PURPOSE

Axillary lymph nodes (LNs) with cortical thickness > 3 mm have a higher likelihood of malignancy. To examine the positive predictive value (PPV) of axillary LN cortical thickness in newly diagnosed breast cancer patients, and nodal, clinical, and tumor characteristics associated with axillary LN metastasis.

METHODS

Retrospective review of axillary LN fine needle aspirations (FNAs) performed 1/1/2018-12/31/2019 included 135 axillary FNAs in 134 patients who underwent axillary surgery. Patient demographics, clinical characteristics, histopathology, and imaging features were obtained from medical records. Hypothesis testing was performed to identify predictors of axillary LN metastasis.

RESULTS

Cytology was positive in 72/135 (53.3%), negative in 61/135 (45.2%), and non-diagnostic in 2/135 (1.5%). At surgery, histopathology was positive in 84 (62.2%) and negative in 51 (37.8%). LN cortices were thicker in metastatic compared to negative nodes (p < 0.0001). PPV of axillary LNs with cortical thickness ≥ 3 mm, ≥ 3.5 mm, ≥ 4 mm and, ≥ 4.25 mm was 0.62 [95% CI 0.53, 0.70], 0.63 [0.54, 0.72], 0.67 [0.57, 0.76] , and 0.74 [0.64, 0.83], respectively. At multivariable analysis, abnormal hilum (OR = 3.44, p = 0.016) and diffuse cortical thickening (OR = 2.86, p = 0.038) were associated with nodal metastasis.

CONCLUSION

In newly diagnosed breast cancer patients, increasing axillary LN cortical thickness, abnormal fatty hilum, and diffuse cortical thickening are associated with nodal metastasis. PPV of axillary LN cortical thickness ≥ 3 mm and ≥ 3.5 mm is similar but increases for cortical thickness ≥ 4 mm. FNA of axillary LNs with cortex < 4 mm may be unnecessary for some patients undergoing sentinel LN biopsy.

The role of pre-operative axillary ultrasound in assessment of axillary tumor burden in breast cancer patients: a systematic review and meta-analysis

BACKGROUND

Recent studies have suggested that a significant proportion of patients with axillary nodal metastases diagnosed by pre-operative axillary ultrasound (AUS)-guided needle biopsy were over-treated with axillary lymph node dissection (ALND). The role of routine AUS and needle biopsy in early breast cancer was questioned. This review aims to determine if pre-operative AUS could predict the extent of axillary tumor burden and need of ALND.

METHODS

PubMed and Embase literature databases were searched systematically for abnormal AUS characteristics and axillary nodal burden. Studies were eligible if they correlated the sonographic abnormalities in AUS with the resultant axillary nodal burden in ALND according to the ACOSOG Z0011 criteria.

RESULTS

Eleven retrospective studies and one prospective study with 1658 patients were included. Sixty-five percent of patients with one abnormal lymph node in AUS and 56% of those with two had low axillary nodal burden. Using one abnormal lymph node as the cut-off, the pooled sensitivity and specificity in prediction of axillary nodal burden were 66% (95%CI 63-69%) and 73% (95% CI 70-76%), respectively. Across the six studies that evaluated suspicious nodal characteristics, increased nodal cortical thickness may be associated with high axillary nodal burden.

CONCLUSION

More than half of the patients with pre-operative positive AUS and biopsy proven axillary nodal metastases were over-treated by ALND. Quantification of suspicious nodes and extent of cortical morphological changes in AUS may help identify suitable patients for sentinel lymph node biopsy.

Does ultrasound evaluation of the axilla increase the rate of axillary lymph node dissection in early stage clinically node negative breast cancer patients?

Background

Management and axillary staging of breast cancer has become less invasive and more conservative, over the decades. Considering Z011, axillary lymph node dissection (ALND) can be avoided in T1-2 N0-1 breast cancers with one or two positive sentinel lymph nodes (SLNs), if they are candidates for breast conserving surgery and radiotherapy. The aim of this study was to recognize if pre-operative axillary US evaluation in early-stage breast cancer could lead to more ALND in post Z011 era.

Method

463 breast cancer patients were evaluated. 368 early-stage breast cancer patients (T1-2 N0) were included. We did not perform axillary US in early stage clinically node negative patients; however, 97 patients had axillary US prior to our visit. If axillary US could detect more than two suspicious LNs, US guided biopsy was performed. The remaining clinically node negative patients underwent upfront SLNB. ALND was performed if more than two SLNs were metastatic, or US-guided ALN biopsy proved metastatic involvement.

Results

97 patients had axillary US evaluation before the surgery. 67 patients (69.2%) did not have any suspicious US detected axillary LNs, 17 patients (17.5%) had one, 7 patients (7.2%) had two, and 6 patients (6.2%) had more than two suspicious LNs according to their axillary US evaluation. Those with more than two suspicious LNs underwent ALN US-guided biopsy. Metastatic involvement of the LNs was proved in all of them and they underwent upfront ALND. ALND revealed more than 2 metastatic LNs in 2/6 patients (33.3%). 91 patients who were evaluated by axillary US, had less than two US detected suspicious LNs and underwent SLNB. Amongst 24 patients with one or two US detected suspicious LNs, 1/24 patient had more than two positive SLNs and underwent ALND. In this group 15.6% underwent ALND and 5.2% of them were unnecessary according to the recent guidelines. Axillary US had a false positive rate of 36.6%. The sensitivity of axillary US in distinguishing patients with more than two suspicious LNs in clinically node negative patients was 25%. In the second group (without pre-operative axillary US evaluation), SLNB was performed. 204/272 patients (75%) did not have LN metastasis. 54/272 patients (19.9%) had one or two metastatic SLNs and according to Z011, ALND was omitted. 5.1% had more than two metastatic SLNs and underwent ALND.

Conclusion

US evaluation of the axilla in early stage, clinically node negative breast cancer patients, is not sensitive enough to recognize more than two metastatic ALNs. It leads to more unnecessary ALND. Despite the small number of patients in this study, these results question the rationale of axillary US guided biopsy in low burden (less than two) suspicious LNs. looking for an imaging modality with a higher sensitivity in detecting the Burdon of axillary metastatic involvement is mandatory.

Application of the ACOSOG Z0011 criteria to Chinese patients with breast cancer: a prospective study

Background

Although the ACOSOG Z0011 study showed that axillary lymph node dissection (ALND) could be avoided in a specific population of sentinel lymph node-positive patients, it is not widely accepted by Chinese surgeons. We conducted a prospective single-arm study to confirm whether or not the results of Z0011 are applicable to Chinese patients.

Methods

Patients conforming to the Z0011 criteria were prospectively enrolled at the Peking University People’s Hospital Breast Center from November 2014 to June 2019. The clinicopathological features of the study group were compared with those of the Z0011 study group. Lymphedema after surgery, the incidence of local-regional recurrence, and survival were analyzed.

Results

One hundred forty-two patients who met the Z0011 eligibility criteria were enrolled in this study; 115 underwent sentinel lymph node biopsy (SLNB) alone. Compared with the Z0011 trial, younger patients were included (median age, 52 [26–82] years vs 54 [25–90] years; P = 0.03). For clinical T stage, tumor histology, hormone status, lymphovascular invasion, and the number of positive sentinel lymph nodes (SLNs), no statistically significant differences were observed. More patients received adjuvant chemotherapy and endocrine therapy in this study (90.85% vs 58.0% and 80.99% vs 46.6% respectively, P <0.001). A similar percentage of patients received radiotherapy, but more nodal radiotherapy procedures were carried out in our study (54.5% vs 16.9%). After a median follow-up of 29 months, only 1 patient (0.9%) had ipsilateral breast tumor recurrence, and no regional recurrence occurred.

Conclusion

Our study showed that it is achievable to avoid ALND in patients eligible for Z0011 in China.

Trial registration

ClinicalTrials.gov. Registration number NCT03606616. Retrospectively registered on 31 July 2018.