Limited surgery can reduce swelling after breast cancer

Breast cancer can spread to the lymph nodes in the armpit. A difficult question for surgeons is what to do when patients have axillary metastases, which are only detected when resected tissue is analyzed.

Pain and swelling

If many lymph nodes are removed, the risk of lymphedema in the arm increases. This occurs when lymph fluid cannot flow as freely as before. Lymphedema can cause arm swelling, pain, and affect movement.

We want to try to carry out more precise interventions to spare patients from annoying side effects. But we need to know that it is safe, says Jana de Boniface, a breast cancer surgeon at Capio St. Goran Hospital and a researcher at the Karolinska Institutet, in a press release.

When no spread of cancer is known, the surgeon usually removes so-called sentinel glands, to which lymph fluid from the chest reaches first. If they contain single tumor cells or metastases, which are less than 2 mm in size, the rest of the lymph nodes are left in the armpit. Previous studies have shown that it is safe for the patient.

Patients with larger metastases

Now a large study has investigated the case of larger metastases. The research conducted by Karolinska Institutet includes nearly 2,800 patients from five countries. All had metastases larger than 2 mm in the resected sentinel glands.

One group of patients had what is called an axillary evacuation, which means removing several lymph nodes. In other cases, the armpit is left alone.

After the operation, most patients were treated with cytostatics or anti-hormonal therapy and radiation.

Most lymph nodes can be left behind

The study shows that relapse was equally common in both groups. In contrast, 13% of patients who had multiple lymph nodes removed reported serious problems with their arm function. This compares to four percent among those who only had their guard glands removed.

Our assessment is that it is safe for patients to refrain from axillary evacuation if there are a maximum of two large metastases in the sentinel glands. In these cases, axillary evacuation is replaced by radiation therapy to the axilla, which causes less discomfort in the arm. Jana de Boniface says it has already been introduced into clinical practice in Sweden.

Scientific study:

Deletion of axillary dissection in breast cancer with sentinel node metastases, New England Journal of Medicine.