Management of the Axilla in patients with Breast Cancer: De-escalation of Treatment

For most of the last decade, women who were told they had a positive lymph node were also told that the whole armpit needs to come out. That’s no longer automatically true. A sentinel node biopsy that comes back positive is now the start of a conversation, not the end of one, and the evidence behind that shift has been building since a landmark 2017 trial in JAMA.

Below is where axillary surgery stands in 2026, including the four options on the table, who each one suits, and why “positive node means full clearance” is no longer the rule.

Key Takeaways

• Axillary surgery now lies on a spectrum rather than a binary choice: omission, sentinel node biopsy (SNB), targeted axillary dissection (TAD), and axillary lymph node dissection (ALND).
• A positive sentinel node no longer automatically triggers full clearance. Trials including ACOSOG Z0011 found no survival difference between SNB alone and ALND in selected patients with limited nodal spread.
• De-escalation exists to reduce lymphoedema.
• TAD combines the sentinel node with a previously clipped positive node, resulting in a false-negative rate low enough that many initially node-positive patients can avoid full clearance after chemotherapy.
• In carefully selected, low-risk, node-negative patients, some trials now support skipping axillary surgery altogether.

Why the Axilla Gets So Much Attention in Breast Cancer Surgery

The axilla is the armpit, and it’s where lymph fluid from the breast drains first. That makes the lymph nodes sitting there the most reliable place to check whether breast cancer has started to spread beyond the breast itself.

For decades, checking meant removing. Surgeons took out most or all of the nodes in the armpit (a full axillary lymph node dissection (ALND)), simply to find out whether any of them contained cancer cells. It worked, but it came at a cost: numbness, restricted shoulder movement, and a meaningfully higher chance of lymphoedema, a chronic swelling of the arm that can develop months or years after surgery.

The introduction of sentinel lymph node biopsy in the 1990s changed that equation. Rather than removing the whole basin of nodes, a surgeon identifies and removes only the first or first few nodes the tumour drains into (the “sentinel” nodes) using a radioactive tracer or blue dye. If those nodes are clear, the rest are very likely clear too, and can usually be left alone.

That single change is why most women having breast cancer surgery today don’t wake up with a fully cleared armpit. But the story hasn’t stopped there. What’s changed more recently is what happens after a sentinel node comes back positive.

The Spectrum: Four Ways of Managing the Axilla

Rather than a straight choice between “biopsy” and “clearance,” axillary management in 2026 encompasses four options, as reflected in Cancer Australia’s clinical practice guidance on staging and managing the axilla. Which one applies depends on tumour size, whether the nodes were suspicious before surgery, and whether chemotherapy is given before or after the operation.

1. Omitting axillary surgery altogether

For a select group of patients (typically those with a small tumour (under 2cm) and a normal-looking axilla on pre-operative ultrasound), some current evidence supports skipping axillary surgery entirely. The SOUND trial, a randomised study of 1,405 women published in JAMA Oncology in 2023, found that omitting axillary surgery was non-inferior to sentinel node biopsy for five-year survival in this specific group. This only applies where the result of a biopsy wouldn’t actually change the treatment plan.

2. Sentinel Node Biopsy (SNB)

This remains the standard staging step for most women having breast-conserving surgery, such as a breast lumpectomy or mastectomy, where the axilla hasn’t shown obvious signs of spread beforehand. A small number of nodes are removed and checked under a microscope. If they’re clear, no further axillary surgery is needed. If cancer is found, the conversation moves to one of the next two options rather than jumping straight to full clearance.

3. Targeted Axillary Dissection (TAD)

TAD applies to women who have had a confirmed positive node before starting chemotherapy. At diagnosis, that positive node is marked with a small clip. After chemotherapy, the surgeon removes the clipped node together with the sentinel nodes, rather than clearing the entire armpit. Because the clipped node is deliberately included, TAD reduces the false-negative rate to around 5% or lower, which is sufficiently accurate to guide whether further axillary surgery is genuinely needed. For many patients who respond well to chemotherapy, this means ALND can be avoided entirely.

4. Axillary Lymph Node Dissection (ALND)

Full clearance still has a clear place. It’s typically reserved for more extensive nodal disease, a poor response to chemotherapy, or situations where TAD or SNB alone wouldn’t give reliable enough staging information. ALND remains the most effective way to physically remove disease from the armpit, but it’s no longer routinely performed in every patient with any degree of nodal involvement.

Why Less Surgery to the Armpit Matters: The Lymphoedema Question

The reason de-escalation exists at all isn’t cosmetic. It’s about lymphoedema.

Removing lymph nodes disrupts the normal drainage of lymph fluid from the arm. In some women, that fluid then builds up over time, causing persistent swelling, tightness, and reduced arm function that can last for years. A 2013 systematic review and meta-analysis covering data from over 29,000 women found that around 21% of breast cancer patients develop unilateral arm lymphoedema overall, but the rate after ALND (around 20%) was roughly four times higher than after sentinel node biopsy alone (around 6%).

That difference is the entire rationale behind the shift toward de-escalation. Every step down the spectrum is a step toward reducing the number of nodes disturbed, and with it, the long-term risk to arm function.

A Positive Sentinel Node Doesn’t Always Mean Full Clearance Anymore

Finding cancer cells in a sentinel node no longer automatically means an axillary lymph node dissection is needed.

The evidence for this comes from the ACOSOG Z0011 trial, a randomised study that followed women with one or two positive sentinel nodes for ten years. Women who had sentinel node biopsy alone had a 10-year overall survival of 86.3%, compared with 83.6% for those who went on to have full clearance, a difference the researchers concluded did not support routine use of ALND in this group. Similar reasoning underpins TAD in the neoadjuvant setting: pooled data across multiple international cohorts have shown axillary recurrence rates under 1% after de-escalated surgery, with no meaningful difference in outcomes compared with full clearance.

This doesn’t mean a positive node is ignored. It means the decision about what to do next depends on how many nodes are involved, the size of the deposit, whether radiotherapy is also planned, and the biology of the tumour. This is exactly why this is a discussion to have with your surgeon, rather than something to assume either way based on a single test result.

How This Fits Into Your Treatment Plan

Axillary management doesn’t happen in isolation. It’s planned alongside the surgery to the breast itself. Whether you’re having a breast lumpectomy, oncoplastic breast surgery, or a mastectomy, the approach to your lymph nodes is worked out at the same time, based on your imaging, tumour characteristics, and whether chemotherapy is planned before or after surgery.

It’s also part of why more women in NSW are choosing lumpectomy over mastectomy, where it’s clinically appropriate. Breast-conserving approaches and axillary de-escalation have developed alongside each other, both aimed at achieving the same cancer control with less long-term impact on the body. The benefits of oncoplastic breast surgery follow the same logic: treating the cancer thoroughly while preserving as much normal function and appearance as safely possible.

Dr Michael Yunaev discusses axillary management as part of every breast cancer treatment plan at Breast & Body Clinic, working through which of these four options applies to your specific diagnosis, imaging findings, and treatment sequencing.

Discussing Your Options With Dr Yunaev

Axillary management has moved a long way from “biopsy versus clearance,” and it’s worth going into your consultation understanding that a positive result doesn’t automatically mean the most extensive surgery.

Dr Michael Yunaev, Specialist Breast and General Surgeon at Breast & Body Clinic, discusses which of these approaches applies to your diagnosis as part of your treatment planning. Call (02) 9819 7449 or book a consultation online to talk through your options.