Does preoperative axillary staging lead to overtreatment of women with screen-detected breast cancer?

Axillary Management: How Much Is Too Much?

PURPOSE OF REVIEW

To review the current management of the axilla in breast cancer.

RECENT FINDINGS

Axillary dissection is no longer indicated in patients with clinically node-negative axilla with 1-2 positive sentinel lymph nodes following upfront surgery or in patients with clinically node-negative axilla following neoadjuvant chemotherapy. Breast cancer has evolved away from routine axillary clearance to the less invasive sentinel lymph node biopsy to now complete omission of axillary sampling in select patients. We will review the most salient evidence that has shaped these practice changes over the last three decades. Current practice controversies are especially relevant for elderly populations and those receiving neoadjuvant therapy. Ongoing clinical trials will provide data to further guide breast cancer surgical management.

Axillary ultrasonography for early-stage invasive breast cancer

BACKGROUND

Among women with early invasive breast cancer and 1-2 positive sentinel nodes, sentinel lymph node biopsy (SLNB) is non-inferior to axillary lymph node dissection (ALND).1-3 However, preoperative axillary ultrasonography (AxUS) may not be sensitive enough to discriminate burden of nodal metastasis in these patients, potentially leading to overtreatment.4-6 This study compares axillary operation rates in patients who did and did not receive preoperative AxUS, assessing its utility and risks for overtreatment.

METHODS

This is a retrospective cohort study of patients with clinical T1/T2 breast tumors who were clinically node negative and underwent an axillary operation.

RESULTS

Patients who had preoperative AxUS received more ALND compared to patients who did not (5.6% vs. 1.4%, p ​< ​0.001). There was no significant difference in the number of additional axillary operations following SLNB (2.1% vs. 2.3%, p ​= ​0.77).

CONCLUSION

Eliminating preoperative AxUS is associated with fewer invasive ALND procedures, without increased rate of axillary reoperations.

Predictive value of combining clinicopathological, multimodal ultrasonic characteristics in axillary lymph nodal metastasis burden of patients with cT1-2N0 breast cancer

OBJECTIVE

Since the ACOSOG Z0011 trial, the clinical examination of axillary lymph node-negative early breast cancer patients (cT1-2N0) can be used to predict the burden of axillary lymph nodes (ALNs) by axillary ultrasound (AUS). To improving diagnosis of axillary lymph node metastasis (ALNM), we assessed the value of combining clinicopathological, conventional ultrasound, SWE features in the cT1-2N0 breast cancer patients.

METHODS

Retrospective analysis of 285 patients with cT1-2N0 breast cancer who underwent preoperative ultrasound examination of the lesion and axillary, with shear wave elastography (SWE) of the lesions. According to the postoperative pathological results, they were divided into ≤2 metastatic ALNs group (low nodal burden, LNB) and >  2 metastatic ALNs group (high nodal burden, HNB). Binary logistic regression analysis was used to screen independent risk factors and establish prediction models. The best cut-off value of continuous variables is determined by the receiver operating characteristic curve, and the performance of the prediction model is evaluated.

RESULTS

Presence of lymphovascular invasion (OR = 7.966, P = 0.010), tumor size (OR = 2.485, P = 0.019), Emean of intratumor (OR = 0.939, P = 0.002) and cortical thickness of lymph node (OR = 9.277, P <  0.001) were independent risk predictors for HNB of cT1-2N0 Group. The predictive model of combined method had better performance in predicting HNB of cT1-2N0 compared with models based on SWE and conventional ultrasound alone (area under the curve: 0.824 vs 0.658, P <  0.001; 0.824 vs 0.789, P = 0.035).

CONCLUSIONS

The predictive models of combined method obtained from significant clinicopathological and ultrasonographic features can potentially improve the diagnosis and individual treatment of ALNM in patients with cT1-2N0 breast cancer.

Imaging features of sentinel lymph node mapped by multidetector-row computed tomography lymphography in predicting axillary lymph node metastasis

INTRODUCTION

Accurately assessing axillary lymph node (ALN) status in breast cancer is vital for clinical decision making and prognosis. The purpose of this study was to evaluate the predictive value of sentinel lymph node (SLN) mapped by multidetector-row computed tomography lymphography (MDCT-LG) for ALN metastasis in breast cancer patients.

METHODS

112 patients with breast cancer who underwent preoperative MDCT-LG examination were included in the study. Long-axis diameter, short-axis diameter, ratio of long-/short-axis and cortical thickness were measured. Logistic regression analysis was performed to evaluate independent predictors associated with ALN metastasis. The prediction of ALN metastasis was determined with related variables of SLN using receiver operating characteristic (ROC) curve analysis.

RESULTS

Among the 112 cases, 35 (30.8%) cases had ALN metastasis. The cortical thickness in metastatic ALN group was significantly thicker than that in non-metastatic ALN group (4.0 ± 1.2 mm vs. 2.4 ± 0.7 mm, P < 0.001). Multi-logistic regression analysis indicated that cortical thickness of > 3.3 mm (OR 24.53, 95% CI 6.58-91.48, P < 0.001) had higher risk for ALN metastasis. The best sensitivity, specificity, negative predictive value(NPV) and AUC of MDCT-LG for ALN metastasis prediction based on the single variable of cortical thickness were 76.2%, 88.5%, 90.2% and 0.872 (95% CI 0.773-0.939, P < 0.001), respectively.

CONCLUSION

ALN status can be predicted using the imaging features of SLN which was mapped on MDCT-LG in breast cancer patients. Besides, it may be helpful to select true negative lymph nodes in patients with early breast cancer, and SLN biopsy can be avoided in clinically and radiographically negative axilla.

Contrast-Enhanced Ultrasound for Precise Sentinel Lymph Node Biopsy in Women with Early Breast Cancer: A Preliminary Study

BACKGROUND

Sentinel lymph node biopsy (SLNB), as a common method for axillary staging of early breast cancer, has gradually attracted people's attention to the false-negative rate and postoperative complications. The aim of the study is to investigate the clinical value of preoperative contrast-enhanced ultrasound (CEUS) for intraoperative SLNB in early breast cancer patients.

METHODS

A total of 201 patients scheduled for SLNB from September 2018 to April 2021 were collected consecutively. Preoperative CEUS was used to identify sentinel lymph nodes (SLN) and lymphatic drainage in breast cancer patients.

RESULTS

The SLN identification rate of CEUS was 93.0% (187/201) and four lymphatic drainage patterns were found: single LC to single SLN (70.0%), multiple LCs to single SLN (8.0%), single LC to multiple SLNs (10.2%), and multiple LCs to multiple SLNs (11.8%). The Sen, Spe, PPV, NPV, AUC of CEUS, US and CEUS + US in diagnosis of SLNs were 82.7%, 80.4%, 73.8%, 87.4%, 0.815; 70.7%, 77.7%, 68.0%, 79.8%, 0.742; and 86.7%, 77.7%, 72.2%, 89.7%, 0.822, respectively. There was no statistically significant difference between the diagnostic performance of CEUS and CEUS + US (p = 0.630).

CONCLUSIONS

CEUS can be used to preoperatively assess the lymphatic drainage patterns and the status of the SLNs in early breast cancer to assist precision intraoperative SLNB.

Clinical and ultrasound features correlated with a heavy axillary nodal tumor burden in colon cancer

Aim: This study aimed to investigate the correlation between the pathologic and ultrasound (US) characteristics of colon cancer and the heavy axillary nodal burden. Methods: In total, 631 patients diagnosed with invasive colon cancer were recruited with ethical ratification. Results: The unitary pathologic features correlated with heavy axillary lymph nodal burden included the age of patient (p = 0.035), tumor size (p = 0.001), lymph node metastasis (p = 0.001), lymphovascular invasion (p = 0.020) and pathology type (p = 0.012). The independent US characteristics correlated with heavy axillary nodal burden included posterior acoustic enhancement (p = 0.006). Heavy axillary nodal burden was correlated with tumor size, lymph node metastasis, lymphovascular invasion and pathology type. Conclusion: Tumor size, lymph node metastasis and posterior acoustic can be used to predict the axillary lymph node tumor burden.

Pretherapeutic Imaging for Axillary Staging in Breast Cancer: A Systematic Review and Meta-Analysis of Ultrasound, MRI and FDG PET

BACKGROUND

This systematic review aimed at comparing performances of ultrasonography (US), magnetic resonance imaging (MRI), and fluorodeoxyglucose positron emission tomography (PET) for axillary staging, with a focus on micro- or micrometastases.

METHODS

A search for relevant studies published between January 2002 and March 2018 was conducted in MEDLINE database. Study quality was assessed using the QUality Assessment of Diagnostic Accuracy Studies checklist. Sensitivity and specificity were meta-analyzed using a bivariate random effects approach; Results: Across 62 studies (n = 10,374 patients), sensitivity and specificity to detect metastatic ALN were, respectively, 51% (95% CI: 43-59%) and 100% (95% CI: 99-100%) for US, 83% (95% CI: 72-91%) and 85% (95% CI: 72-92%) for MRI, and 49% (95% CI: 39-59%) and 94% (95% CI: 91-96%) for PET. Interestingly, US detects a significant proportion of macrometastases (false negative rate was 0.28 (0.22, 0.34) for more than 2 metastatic ALN and 0.96 (0.86, 0.99) for micrometastases). In contrast, PET tends to detect a significant proportion of micrometastases (true positive rate = 0.41 (0.29, 0.54)). Data are not available for MRI.

CONCLUSIONS

In comparison with MRI and PET Fluorodeoxyglucose (FDG), US is an effective technique for axillary triage, especially to detect high metastatic burden without upstaging majority of micrometastases.

Axillary Nodal Evaluation in Breast Cancer: State of the Art

Axillary lymph node (LN) metastasis is the most important predictor of overall recurrence and survival in patients with breast cancer, and accurate assessment of axillary LN involvement is an essential component in staging breast cancer. Axillary management in patients with breast cancer has become much less invasive and individualized with the introduction of sentinel LN biopsy (SLNB). Emerging evidence indicates that axillary LN dissection may be avoided in selected patients with node-positive as well as node-negative cancer. Thus, assessment of nodal disease burden to guide multidisciplinary treatment decision making is now considered to be a critical role of axillary imaging and can be achieved with axillary US, MRI, and US-guided biopsy. For the node-positive patients treated with neoadjuvant chemotherapy, restaging of the axilla with US and MRI and targeted axillary dissection in addition to SLNB is highly recommended to minimize the false-negative rate of SLNB. Efforts continue to develop prediction models that incorporate imaging features to predict nodal disease burden and to select proper candidates for SLNB. As methods of axillary nodal evaluation evolve, breast radiologists and surgeons must work closely to maximize the potential role of imaging and to provide the most optimized treatment for patients.

Can We Identify or Exclude Extensive Axillary Nodal Involvement in Breast Cancer Patients Preoperatively?

Background

Breast cancer treatment has rapidly changed in the last few years. Particularly, treatment of patients with axillary nodal involvement has evolved after publication of several randomized clinical trials. Omitting axillary lymph node dissection in selected early breast cancer patients with one or two positive sentinel nodes did not compromise overall survival nor regional disease control in these trials. Hence, either excluding or identifying extensive axillary nodal involvement becomes increasingly important.

Purpose

To evaluate whether the current diagnostic modalities can accurately identify or exclude extensive axillary nodal involvement. Evaluated modalities were axillary ultrasound, ultrasound-guided needle biopsy, MRI, and PET/CT.

Methods

A literature search was performed in the Cochrane Library, EMBASE, and PubMed databases up to June 2019. The search strategy included terms for breast cancer, lymph nodes, and the different imaging modalities. Only articles that reported pathological N-stage or the total number of positive axillary lymph nodes were considered for inclusion. Studies with patients undergoing neoadjuvant systemic therapy were excluded.

Conclusion

There is no evidence that any of the current preoperative axillary imaging modalities can accurately exclude or identify breast cancer patients with extensive nodal involvement. Both negative PET/CT and negative MRI scans (with gadolinium-based contrast agents) are promising in excluding extensive nodal involvement. Larger studies should be performed to strengthen this conclusion. False-negative rates of axillary ultrasound and ultrasound-guided needle biopsy are too high to rely on negative results of these modalities in excluding extensive nodal involvement.

Pretreatment Tattoo Marking of Suspicious Axillary Lymph Nodes: Reliability and Correlation with Sentinel Lymph Node

BACKGROUND

Tattooing is an alternative method for marking biopsied axillary lymph nodes (ALNs) before initiation of treatments for newly diagnosed breast cancer. Detection of black ink-stained nodes is performed under direct visualization at surgery and is combined with sentinel node (SLN) mapping procedures.

METHODS

Women with newly diagnosed breast cancer who underwent fine or core-needle biopsy of suspicious ALNs were recruited. The nodal cortex and perinodal soft tissue was injected with 0.1-1.0 ml of Spot™ (GI Supply) black ink under ultrasound guidance. Intraoperatively, black stained nodes were removed along with SLNs, noting concordance between the two.

RESULTS

Sixty-six evaluable patients were enrolled (2013-2017). Nineteen received surgery first (Group 1) and 47 neoadjuvant therapy (NAT, Group 2). The average number of nodes tattooed was 1.16 for Group 1 and 1.04 for Group 2. The average interval from tattoo to surgery was 21 days (range 1-62) for Group 1 and 148 days (range 71-257) for Group 2. The tattooed node(s) were visually identified at surgery and corresponded to the sentinel lymph node(s) in 98.5% of cases (18/19 in Group 1 and 47/47 in Group 2). Of the 14 patients in Group 2 whose nodes remained positive following NAT, the tattooed node was the SLN associated with carcinoma.

CONCLUSIONS

Tattooing is an alternative method for marking biopsied ALNs. Tattooed nodes coincided with SLNs in 98.5% of cases. This technique is advantageous, because it allows for fewer procedures and lower costs compared with other methods.