Armpit lymph nodes need not be removed in breast cancer recurrence

The wholesale removal of armpit lymph nodes (axillary lymph node dissection) in women with recurring breast cancer turns out to be unnecessary in many cases, with a sentinel lymph node biopsy – already carried out in first-time breast cancer patients – often sufficing to examine for metastases in this group of patients as well. This finding comes out of a study conducted by PhD student and surgeon in training Guusje Vugts at the Catharina hospital. Vugts received her PhD from Maastricht University on Thursday 16 June.

Until recently, removal of all auxiliary lymph nodes was the standard procedure for women faced with a recurrence of breast cancer. Unfortunately, removal of these lymph nodes causes a host of side effects such as loss of sensation, reduced range of motion, fluid build-up in the arm (lymphedema) and a higher susceptibility to infection.

Safe procedure

Guusje Vugts’ research proves that in many cases a new sentinel lymph node can be found, making a sentinel node biopsy a viable and safe intervention for patients who have had breast or underarm surgery before. ‘That means axillary lymph node dissections, which are the standard procedure but have a high risk of postoperative side effects, are unnecessary’, asserts Vugts. Many hospitals have already changed their procedures in response to this finding and adopted the repeat sentinel node biopsy as standard.

The sentinel lymph node is the node that drains lymph fluid from the breast and is typically the first node where the spread of cancer (metastases) can be detected. That makes sentinel node biopsy a good method to examine for possible lymph node metastasis. Vugts explains that ‘Many people think that the sentinel lymph node, or the 'gatekeeper' lymph node as it is sometimes called, is unique – that you have only got one. But it is merely the first 'gate' where fluid and also cancer cells collect. Lymph nodes are basically filters, and the sentinel node is simply the first node of the dozens we have in our armpits where cancer cells can develop.’

More radioactive fluid

In patients with breast cancer recurrence, the sentinel lymph node often is not in the armpit at all, but near the sternum or collarbone, or in the opposite armpit. In her PhD thesis, Vugts concludes that when performing a second sentinel node biopsy, it is crucial to use a higher dose of radioactive dye and to inject it in the right spot. ‘In the tumour or as near to it as possible’, she emphasises. ‘That improves the chances of finding the sentinel node.’ In 80.1% of patients who participated in the study, the new sentinel node was found to be cancer-free and no additional treatment of the lymph nodes was necessary. In more than half (54.1%) of these patients, the new sentinel node was found somewhere other than in the armpit.

Surgical procedures for breast cancer have grown progressively less invasive over the years. Sparing the axillary lymph nodes fits into this trend and represents an important advance for patients because of the fluid retention and associated discomforts removal of these nodes can cause.

Dutch Cancer Society

Thirty-six hospitals took part in the Sentinel Node And Recurrent Breast Cancer (SNARB) study which yielded these findings. Of these, 29 hospitals supplied patient data for a total pool of 536 patients. Based on these data, it could be demonstrated that a sentinel lymph node biopsy can be performed to detect lymph node metastasis even in women with breast cancer recurrence who have had the procedure before. The study was funded in part by the Dutch Cancer Society (KWF).

Also read