An all too-common side effect of breast cancer treatment

In New Zealand, one in nine women will be diagnosed with breast cancer in their lifetime, making it the most common cancer for women.

Over the years survival rates have improved, but despite this up to 40 percent of breast cancer survivors will develop a debilitating and incurable condition after their treatment – lymphoedema – which they will need to manage for the rest of their lives.

Lymphoedema is a chronic disorder of the lymphatic system, which leads to the accumulation of fluid in the body, causing tissue swelling. For breast cancer survivors, this swelling typically occurs in the arms but can also occur in the breast and is particularly common after treatments that affect lymph nodes such as surgery and radiation therapy. Without appropriate diagnosis and management, lymphoedema can progress, causing physical discomfort along with financial and psychological strain.

Lymphoedema can take months to years to develop after cancer treatment and there is no way to predict who will develop it, and who will not. Treatment for other cancers, including melanoma, gynaecological and head and neck, can also result in lymphoedema. My research at the Auckland Bioengineering Institute aims to address this problem.

I became very interested in the lymphatic system over 20 years ago when I carried out my PhD analysing normal lymphatic drainage in melanoma patients. This provided the foundation for me to establish research into lymphoedema, which is characterised by abnormal lymphatic drainage. My work now involves developing advanced computational models – ‘digital twins’ – to simulate the development and progression of lymphoedema, to understand why it is more likely to occur in some people but not in others. Our goal is to further personalise breast cancer treatments to minimise the chance of lymphoedema developing at all.

The impact of my research was brought close to home recently after meeting a colleague at the Auckland Bioengineering Institute who developed lymphoedema this year after treatment for an aggressive form of breast cancer. After being diagnosed one year ago aged 38, and with two young children, she was advised to be aggressive with her treatment to have the best chance of a cure.

She recounts her intensive treatment regime: “I undertook six rounds of chemotherapy followed by bilateral mastectomies with immediate breast reconstruction, 15 rounds of radiation and then a further 11 rounds of immunotherapy.” Fortunately, she had a complete response to chemotherapy and radiation therapy with minimal side effects and completed active treatment just a few weeks ago.

Because of her intensive treatment regime, she was warned by her breast surgeon that she had a high risk of developing lymphoedema, but her focus was on surviving. “My only real thought was ‘well it won’t kill me and staying alive is the most important thing so I will cross that bridge when I come to it’,” she says.

“I thought it would only potentially be a bit of swelling, and I didn’t realise it was incurable at that point.”

After developing symptoms of lymphoedema just two months after she finished radiation therapy, her breast surgeon recommended she see a lymphoedema specialist. She now visits every week to manage her condition and is frustrated by the lack of treatment options and inequity in availability of support.

“Despite having really extensive insurance none of my lymphoedema treatment is covered so I pay out of pocket for drainage massage and expensive support garments,” she says. “I am really aware of my privilege in being able to do this and it makes me worry about what happens to women who have come out the other side of cancer with lymphoedema who can’t.”

My colleague’s experience highlights the urgent need for more resources and support for women in New Zealand who develop lymphoedema after breast cancer treatment. There is no standardised way to diagnose, treat and support patients and a limited number of expert clinicians and therapists.

My own research into lymphoedema was initiated after an expert in lymphatic anatomy reached out to me from the Australian Lymphoedema Education, Research and Treatment centre, at Macquarie University in Sydney, a specialist clinic offering comprehensive management for lymphoedema. We now have a long-standing collaboration between our centres which helps bring expert knowledge to our team in New Zealand. I have even learned that some New Zealanders with lymphoedema have flown to this centre to receive imaging assessments and personalised treatment plans that were not available to them here.

One of the challenges of researching the lymphatic system is that lymphatic vessels, and the fluid they contain, are clear and invisible to the naked eye. It is also not possible to inject a contrast agent to visualise the entire system because it flows in one direction towards the heart and has many valves along its path. As part of my research work, we are developing improved imaging devices to visualise the lymphatics which will also help inform our computational models. We aim to use these tools to identify whether there are variants in lymphatic anatomy and function that predispose some women to develop lymphoedema after treatment. With the ability to simulate different scenarios, we could identify the best course of treatment for each patient to minimise the chance of developing lymphoedema.

My commitment to reducing the side effects of cancer treatment is deeply personal. Almost 20 years ago now, my 16-year-old brother was diagnosed with leukaemia. During chemotherapy, his suppressed immune system left him vulnerable to a life-threatening fungal infection that began in his sinus, then spread to his left eye and into his brain. Doctors could not treat both conditions at the same time, therefore his treatment was compromised and he passed away 18 months later. Witnessing the severity of my brother’s treatment complications instilled in me a strong desire to improve cancer care and ensure patients receive the safest, most effective treatment possible.

For my work colleague, and for many other breast cancer survivors, lymphoedema has become a reality that they did not expect but now need to manage for the rest of their lives, often at significant cost.

We must do better to understand this common side effect, which is under-researched, under-diagnosed and receives little support in the public and private health systems. Despite great strides being made improving breast cancer survival rates, advancements in understanding and preventing lymphoedema are lagging too far behind.