Researchers have pinpointed changes in the structure of lymph nodes which could help identify people who are at higher or lower risk of breast cancer spreading.
A study found that the structure of a network that supports lymph nodes could change due to the disease even before doctors are able to spot any cancer cells there.
Some changes were linked to a better chance of survival, while others led to a worse prognosis for the patient.
Researchers said the findings could guide treatment decisions and help more people avoid unnecessary treatment.
Lymph nodes play a key role in the immune system, helping the body fight infections and cancer.
In breast cancer, the lymph nodes in the armpit are often the first place the disease spreads to and, at the moment, everyone with invasive breast cancer undergoes surgery to remove lymph nodes to check for cancer cells.
While this is effective, it can lead to long-term side effects like swelling of the arm (lymphoedema) and may be unnecessary for some patients.
The new research, funded by the charity Breast Cancer Now, could therefore help identify people who are at higher or lower risk of breast cancer spreading.
“These findings suggest that changes to the structure of the lymph nodes are more than just a consequence of the cancer. They can also play an active role in helping breast cancer progress,” said Dr Simon Vincent, chief scientific officer at UK charity Breast Cancer Now:
“With one person tragically dying from breast cancer every 45 minutes in the UK, we urgently need research like this so that we can better understand who is most at risk of their cancer progressing and becoming incurable. Only then we can find ways to stop it,” Vincent said.
“With a better understanding of how lymph nodes change as breast cancer spreads, we could find new targets for future treatments for types of breast cancer that are harder to treat.”
Dr Amy Llewellyn and Dr Kalnisha Naidoo from King’s College London, together with Professor Sophie Acton at University College London, studied 331 lymph node samples taken from people with different types of breast cancer and compared them to healthy lymph nodes in people free from the disease.
They looked at a unique group of cells within lymph nodes called fibroblastic reticular cells (FRC).
The FRC network provides the structure for the lymph node, controls fluid flow and activates different immune cells.
The team found that the structure of this FRC network can change even before the breast cancer has spread and the changes were different depending on the type of breast cancer, any spread, and whether someone had received chemotherapy.
In the future, these findings could support new treatments, more tailored care and ensure more people avoid unnecessary side-effects.
Dr Llewellyn said: “Until now we have not fully understood how and when lymph nodes become altered in a way that allows cancer to spread.
“As a result, every breast cancer patient currently must have some of their lymph nodes removed for accurate staging and treatment planning.
“While this is effective, it can lead to long-term complications and may be unnecessary for some patients, particularly those with early-stage disease or those whose cancer responds well to treatment.
“There is therefore an urgent need to better understand the biology of the lymph node chain and our study addresses this gap by providing the first large-scale analysis of FRC in human lymph node tissue from breast cancer patients.”
Ruth Smith, 59, from Buckinghamshire in England, was diagnosed with triple negative breast cancer in January 2023 after discovering a lump in her right breast.
“Going through breast cancer treatment and being told that lymph nodes needed to be removed was daunting, and at the time I just focused on doing whatever was necessary to treat the cancer,” she said.
“The swelling and discomfort can have a real impact on daily life, and it’s something I now have to manage long-term,” she said.
“Research like this is so important because it could help doctors better understand who really needs which treatments, and hopefully reduce the number of people who go on to develop lymphoedema in the future.”
The research is published in the Journal of Pathology.
