Study identifies lymph node changes linked to breast cancer spread risk

A study of lymph node tissue from breast cancer patients identified structural changes in a supporting cell network that occur before cancer cells are detectable. The alterations differed according to cancer subtype, whether the disease had spread, and whether chemotherapy had been given.

Lymph nodes in the armpit are the first site where breast cancer often spreads. Standard care currently requires surgical removal of these nodes for examination in every patient with invasive disease.

Study methods and findings Researchers compared samples from 331 lymph nodes taken from patients with various breast cancer types against healthy nodes from people without the disease. They focused on fibroblastic reticular cells that form the node’s internal structure, regulate fluid flow, and activate immune cells.

The team reported that the network of these cells can reorganize even before cancer spreads and that the reorganization patterns correlate with patient outcomes. Some patterns were associated with longer survival; others indicated higher risk of progression.

Potential effects on treatment decisions The study was funded by the charity Breast Cancer Now. Its authors stated that mapping these changes could help identify patients at higher or lower risk of spread and reduce unnecessary node removal for some.

Current node removal can cause long-term arm swelling known as lymphoedema. The researchers noted that avoiding surgery in low-risk cases could limit this side effect. A patient diagnosed with triple negative breast cancer in January 2023 described developing lymphoedema after node removal and said research clarifying who needs the procedure would be valuable.