Cancer cachexia: the hidden problem
Many people who have come across loved ones with cancer will notice that their weight and physical strength change over the course of the disease and treatment. This was exactly what I noticed when I visited my family friend who had liver cancer just about a month before she passed away.
I was shocked that she was awfully thin, that she had no appetite and couldn’t eat much. But as surprised as I was on her drastic change in weight (she wasn’t a thin person originally), I remember that I was rather more concerned about the status of her cancer and her response to treatments.
Almost three years later, a discussion in one of my classes on cancer cachexia led me to think back and consider it as a probable contributing factor to my friend’s shortened life.
Cachexia (derived from the Greek kakos and hexis for “bad” and “condition”, respectively) is a syndrome that can result in weight and muscle mass loss, weakness, fatigue and poor performance status (the level of a patient’s functioning in terms of daily and physical activity). It is particularly common in patients in the later stages of various diseases including cancers.
Cachexia affects 50% of all cancer patients, and its prevalence can be as high as 80% in patients with advanced and/or terminal cancer.
Patients experience a weight loss of more than 5% or have a BMI (body-mass index) of less than 20 kg/m2. In addition, patients experience a loss of appetite and have a reduced food intake. Research also showed that loss of skeletal muscle mass contributes more to the severity of cachexia than does loss of fat.
The sad truth is that although it is very prevalent among cancer patients, cachexia can be overlooked by doctors, who usually focus on treating just the cancer itself.
Cancer patients with cachexia have a reduced survival compared to cancer patients with little weight loss or close to normal weight. In addition, patients with greater muscle loss who undergo chemotherapy do not fare as well as patients with lesser muscle loss.
Although cancer cachexia is still not well-recognized clinically, there are nonetheless ongoing efforts in trying to better understand its mechanisms, which will help in developing new treatments.
Indeed, researchers at The Research Institute of the McGill University Health Centre like Drs. Robert Sladek and Simon Wing are investigating the mechanisms of cachexia and its potential treatments, respectively.
Dr. Sladek has been trying to identify genes that tumours use to change cell metabolism to better figure out how to reverse muscle wasting.
Dr. Wing’s research group has been screening chemicals that have the capability to promote muscle cell fusion – the impairment of which was found to contribute to muscle wasting in patients. Chemicals that have positive results in reversing muscle wasting in animal models will be tested further in clinical trials.
For now, cancer cachexia remains a condition that is only palliative, but it shouldn’t have to be, according to ongoing research. Rather than associating cachexia with terminal illness/cancer, we should think of it as a preventable condition if diagnosed early.
As researchers are now suggesting that early diagnosis is the key to prevention, more research needs to be done to properly diagnose patients during the onset of cachexia, as well as bring forth strategies for treatment.
Although there isn’t an “anti-cachexic” pill yet on the market, researchers and clinicians are still working to develop new therapies for clinical trials.
And, it also seems that just “one pill” may not be enough to combat cancer cachexia. Dr. Imed Gallouzi and his research group at the Goodman Cancer Research Centre recently published a research article showing that there are numerous mechanisms linked to cachexia at the cellular level, not just one. This implies that a combination of different therapies may be the answer to treat this syndrome.
How can we improve outcome of cachexic patients? To start, family members and doctors alike should be more aware of patients that may be afflicted cachexia. They should bring this awareness to the medical community – to recognize that cachexia is really an issue not to be overlooked.
We also to need to keep pushing for research and clinical trails for cancer cachexia. We should not neglect a condition that seems only secondary to the primary cancer, as cancer cachexia may have a synergistic effect with cancer in reducing a patient’s chances of survival.
With several clinical trials currently running and the current research that focus on cancer cachexia, we are constantly digging deeper to uncover the many unknowns of this complex syndrome.
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Ma, J. F., Sanchez, B. J., Hall, D. T., Tremblay, A. M. K., Di Marco, S., & Gallouzi, I. E. (2017). STAT3 promotes IFNγ/TNFα‐induced muscle wasting in an NF‐κB‐dependent and IL‐6‐independent manner. EMBO Molecular Medicine, 9(5), 622-637.
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