Sentinel node biopsy after neoadjuvant chemotherapy

Yes, for many people. When chemotherapy or other treatment is given before surgery, known as neoadjuvant treatment, it often shrinks or clears cancer in the armpit lymph nodes as well as in the breast. That creates a chance to avoid removing all the armpit nodes. If your nodes looked normal before treatment, sentinel node biopsy after chemotherapy is widely accepted and works much as it does without chemotherapy. If your nodes contained cancer before treatment, confirmed by a needle biopsy, and they look normal on examination and ultrasound afterwards, a sentinel node biopsy may still be offered. In this situation, chemotherapy can scar the lymph channels, making the test less reliable. Surgeons improve accuracy by using two markers such as a tracer and a dye, by removing at least a few sentinel nodes, and often by removing the node that was clipped at the start. Removing the clipped node together with the sentinel nodes is called targeted axillary dissection. If all the removed nodes are free of cancer, many people can avoid full axillary clearance, usually with radiotherapy to the area afterwards. If any cancer remains in the nodes, further armpit surgery or radiotherapy is generally advised. Your team will plan the approach before chemotherapy starts, so the right markers are in place.

Chemotherapy can clear the nodes

A good response may mean far less armpit surgery.

Extra steps improve accuracy

Two markers, several nodes and the clipped node reduce missed cancer.

Remaining cancer changes the plan

Cancer left in nodes usually leads to more armpit treatment.

This approach spares many people from full clearance, but it helps to understand what is less certain.

The test can miss more often

Scarring after chemotherapy makes false negative results somewhat more likely than in untreated nodes. The extra steps are designed to bring this down.

Long-term data are still growing

Early results show low rates of cancer returning in the armpit, but studies following people for many years are ongoing.

The clip is not always found

Occasionally the marked node cannot be located, and the surgeon may then remove more nodes.

What this page cannot tell you

It cannot predict how your nodes will respond. Your team will judge that from scans and the final report.

The node results after chemotherapy strongly guide the rest of your treatment.

If all removed nodes are clear

Most people avoid axillary clearance. Radiotherapy to the breast or chest wall and nearby nodes is often still recommended when nodes were positive at the start.

If cancer remains

Axillary clearance or radiotherapy to the armpit is usually advised. Extra treatment after surgery may also be offered, depending on the cancer type.

Ongoing follow-up

Regular checks include examination of the armpit, so any change is found early.