Cancer cachexia treatment: urgent action is needed!

Nutrition is a cornerstone of oncological care, yet its importance remains underestimated.

Cancer cachexia—a complex syndrome of muscle loss, inflammation, and metabolic disruption—affects up to 80% of cancer patients and contributes to 20% of cancer-related deaths.

Despite available guidelines and proven interventions, malnutrition often goes undiagnosed, leaving patients vulnerable to complications and reduced treatment efficacy.

The demand for reliable information on nutrition when facing cancer is huge. Thousands of people watched the docuseries (Un)well on Netflix exploring possible benefits of fasting for 28 days while having cancer. This highlights the urgent need for accurate, evidence-based guidance on nutrition for cancer patients.

The medical and scientific community is working hard to provide the right answers, but maybe not hard enough. Or not smartly enough. Because the practical implementation of existing knowledge remains a challenge. As a result, people suffer, and even die.

What is cancer cachexia?

Cachexia is a condition with a combination of factors undermining the entire body. It involves systemic inflammation and loss of muscle mass, including at the level of the heart. But also, intestinal dysfunction, with a gut that doesn’t work the way it’s supposed to. And often, brain inflammation that reduces appetite. Not to forget about the taste and smell alterations that are so typical in certain phases of cancer treatment.

All these will lead to weight loss, the most visible effect. Everyone knows someone who has lost weight due to cancer, either because of the disease itself and/or from its treatment. It’s one of the hallmarks of cancer.

Between 50 and 80% of people confronted with cancer will have to cope with cachexia. And the medical community should help them. Because one out of five cancer patients dies because of malnutrition. That is 20%!

Knowledge is key. Understanding the tumour micro- and macroenvironment is crucial for improving management (1). Over the years, the approach to treating cancer has become more holistic, integrating nutrition assessment and counselling. Or at least, it should.

Understanding metabolism and nutrition can make a difference.

Effective nutritional therapy can make a difference. Well-nourished people will tolerate their primary treatment, such as immunotherapy, radiation, chemotherapy, and surgery, better. They are less likely to need to have their doses reduced or will have less complications after a surgical intervention. They will spend less time in the hospital unplanned. And their quality of life will be better.

Because honestly, how do you feel when you haven’t eaten for a long time? Or when you felt nauseous for days or needed to vomit even without eating? When all the energy is drained out of your body, and there’s no way to recharge? Try to turn your smart phone on with an empty battery. You just won’t make that call.

How to identify malnutrition in cancer patients.

Malnutrition is measurable. We can identify patients at risk with tools such as the Nutritional Risk Score 2002 and the GLIM-criteria (Global Leadership Initiative on Malnutrition), which are well known to healthcare practitioners with expertise in clinical nutrition.

Yet, recent data in Belgium show that although 50% of cancer patients consulting an oncologist are at risk, and 25% of them are malnourished, the diagnosis of malnutrition is not made. The ONCOCARE (2) study literally states: “Malnutrition was largely underestimated by the oncologist.” Shockingly, 9 out of 10 patients did not have a nutritional plan in their medical files.

This is not new. Almost ten years agon we analysed close to 10.000 oncology patients’ files looking for cachexia and nutritional treatment plans. We found slightly better numbers for nutritional interventions than global statistics, but there was still room for improvement (3).

So, the oncology and nutrition departments at UZ Brussels joined forces with IT: every time a body weight difference of more than 5% was detected in our electronic medical system, a question pops up: ‘Do you want to refer the patient to the dietitian/nutrition team: yes or no?’. Thousands of patients were referred and taken care of in the following years. This was artificial intelligence even before we called it that way…

Solutions exist. Guidance is available. Trustworthy organisations such as the European Society for Medical Oncology (ESMO) and the European Society for Clinical Nutrition and Metabolism (ESPEN) have issued guidelines. The missing piece is implementation.

Cancer nutrition training is key for healthcare professionals.

Onco-dietitians know the ins and outs of nutrition during cancer treatment. But there is a financial hurdle to take, and browsing the internet is so much cheaper. Things could be different.

Training for medical doctors in the field of nutritional therapy is largely lacking in Belgium. But this will change. The French-speaking medical universities now have a course available. The Dutch-speaking Micro credential ‘Clinical Nutrition’ will start in October 2025. The knowledge gap is closing. Now, we must ensure its application in clinical practice.

A call to action: now is the time to address cancer malnutrition.

We can bring the scientific evidence to the patients today. We don’t need more data, we can act. We already know how to identify patients with cachexia. We know how to work with them on fortifying food, on how and when to drink oral supplements. We know how to take over when eating is just not possible.

We are here in Belgium, in the possibility to have enteral and parenteral nutrition in the home setting, in a safe and comfortable way. We can act before the battery is running too low. Because we want to avoid it to going completely dead, as it does for 20% of cancer patients.

To all colleagues working with people confronted with cancer: screen, assess, and treat. Do it yourself, refer to a specialist, or work together. The most important is to act. The time is now!

Note: This blog is based on my presentation given at BSMO (the Belgian Society of Medical Oncology) congress, in Bruges, on the 31st of January 2025.

(1) Nature reviews clinical oncology, vol 20, April 2023, 250-264

(2) ONCOCARE, supportive care in cancer (2024) 32:135

(3) Cachexia UFO’s, Nutrition 63-64 (2019) 200-204