What are the indications for targeted axillary dissection (TAD)?

From the Guidelines

Targeted axillary dissection is indicated for breast cancer patients with clinically positive lymph nodes at diagnosis, who have undergone biopsy to document nodal metastases, and for whom upfront surgery is planned. This approach is based on the most recent guidelines from the National Comprehensive Cancer Network (NCCN) [ 1 ], which recommend stratifying patients according to the presence or absence of clinically positive lymph nodes at diagnosis.

Key Considerations

• For patients with positive needle biopsy results, options include proceeding with axillary lymph node dissection (ALND) or considering sentinel lymph node biopsy if the patient meets the ACOSOG Z0011 trial criteria and has low tumor burden [ 1 ].
• The Z0011 criteria include a T1 or T2 tumor, planned breast-conserving surgery and whole-breast radiation, and no preoperative therapy [ 1 ].
• A low tumor burden is defined as lymph nodes that are only radiologically detected with involvement of only 1 or 2 nodes [ 1 ].

Clinical Implications

• The American Society of Clinical Oncology (ASCO) clinical practice guideline update also recommends against axillary lymph node dissection (ALND) for women with early-stage breast cancer who do not have nodal metastases or who have one or two sentinel lymph node metastases and will receive breast-conserving surgery with conventionally fractionated whole-breast radiotherapy [ 1 ].
• However, the NCCN guidelines provide more specific guidance on the management of axillary lymph nodes in breast cancer patients, including the use of targeted axillary dissection for patients with clinically positive lymph nodes at diagnosis [ 1 ].

Recommendations

• Targeted axillary dissection should be considered for breast cancer patients with clinically positive lymph nodes at diagnosis, who have undergone biopsy to document nodal metastases, and for whom upfront surgery is planned.
• The procedure requires multidisciplinary coordination between surgery, radiology, and pathology to ensure proper identification and removal of the targeted nodes.
• By providing more accurate staging of the axilla and reducing the need for complete axillary lymph node dissection, targeted axillary dissection can help reduce complications like lymphedema, shoulder dysfunction, and chronic pain [ 1 ].

From the Research

Indication of Targeted Axillary Dissection

The indication of targeted axillary dissection (TAD) is a significant aspect of breast cancer treatment, particularly for patients with node-positive breast cancer after neoadjuvant chemotherapy.

• TAD is a novel technique that involves the surgical removal of biopsy-proven positive axillary nodes, which are marked prior to neoadjuvant chemotherapy, in addition to the sentinel lymph node biopsy (SLNB) 2.
• The aim of TAD is to decrease the rate of non-therapeutic axillary dissection (ALND) for patients with node-positive breast cancer, while ensuring oncologic safety 3.
• Studies have shown that TAD is associated with a low false-negative rate (FNR), making it a valid alternative to complete axillary lymph node dissection (cALND) in patients with node-positive breast cancer after excellent response to neoadjuvant chemotherapy 2, 3.

Eligibility Criteria for TAD

The eligibility criteria for TAD have been proposed to ensure oncologic safety, including:

• The presence of biopsy-proven positive axillary nodes prior to neoadjuvant chemotherapy 2.
• The successful marking of the positive axillary nodes using a radioactive seed or other methods 4.
• The ability to surgically remove the marked nodes and the sentinel lymph node 2, 3.
• Studies have evaluated the utility of traditional eligibility criteria, including the number of abnormal lymph nodes on axillary ultrasound and the use of single or dual tracers for SLNB 3.

Efficacy of TAD

The efficacy of TAD has been demonstrated in several studies, including:

• A systematic review and pooled analysis of 9 studies, which showed that TAD was associated with a low FNR of 5.18% (95% CI: 3.41-7.54) 2.
• A prospective multicenter registry study, which found that TAD retained a low FNR in advanced clinical T-N stage compared with earlier disease 3.
• A retrospective study, which showed that TAD was successful in 97% of patients, with 50% of patients able to avoid ALND 4.

Comparison with Other Techniques

TAD has been compared with other techniques, including:

• SLNB, which has been shown to be a safe and efficacious component of the surgical treatment of early-stage breast cancer patients 5.
• ALND, which has been shown to result in significant morbidity, but can be avoided in patients with negative SLNB results 6.
• Studies have also compared the costs of TAD with ALND, finding that TAD was associated with increased procedural costs, but similar total hospital stay costs 4.