Conquering Cancer Cachexia
by Egidio Del Fabbro, MD
The term cachexia refers to a specific condition characterized by weight loss, poor appetite, fatigue, and muscle wasting. The combination of muscle wasting, loss of body fat, and decreased appetite can cause dramatic changes in a person’s weight and physical appearance. Unlike starvation, cachexia cannot be reversed by consuming more calories.
What causes cachexia?
Research suggests that a deviant inflammatory response may be the main driver of cachexia. In people with cachexia, proteins called pro-inflammatory cytokines are produced in excess and activate enzymes that break down muscle cells. These cytokines also hinder the body’s efforts at rebuilding muscle by decreasing a person’s sensitivity to hormones that stimulate appetite and muscle growth.
Why some cancer survivors experience cachexia and others do not seems to depend on a combination of factors, including genetic predisposition, type of cancer, and having other illnesses that also cause weight loss (for example, emphysema). Specific gene variations involved with muscle metabolism, fat metabolism, and cytokine production have recently been identified as increasing the risk for cachexia. We also know that certain types of cancer are associated with an increased risk of cachexia; for example, people with lung or pancreatic cancer are more likely to lose weight than those with breast cancer, prostate cancer, or leukemia. In the future, predicting a person’s risk of developing cachexia by analyzing their DNA will enable physicians to introduce effective anti-cachexia therapies soon after diagnosis, perhaps prior to chemotherapy.
What happens when a person has cachexia?
Cachexia often has profound effects on a person’s quality of life, as well as their ability to complete treatment. Several studies have shown that, not only are people more likely to complete chemotherapy, but they also experience fewer side effects if they are able to maintain their weight. On the flipside, severe weight loss of greater than 10 percent may exclude a person from being enrolled in certain clinical trials. When it comes to quality of life, changes in a person’s physical strength, appearance, and body image can provoke anxiety toward, and sometimes even inhibit, intimacy.
Cachexia – or wasting syndrome – is a serious complication of cancer that can affect a person’s ability to complete treatment.
If you’re experiencing cachexia, meal times may become a source of frustration and conflict for you and your family. Your family members may have the false impression that you’re not trying, particularly when you feel full after just a few bites of food. Helping your family understand that early satiety and poor appetite are common issues for people with cachexia often helps to alleviate family anxiety and conflict.
What can I do if I’m experiencing cachexia?
In people with cachexia, controlling other troublesome, coexisting conditions, such as depression, constipation, pain, and nausea, can also improve appetite and quality of life. Fortunately, there are readily available, inexpensive therapies that can manage these side effects very effectively.
In addition to symptom management by your oncologist or palliative care provider, other professionals may play an important role in managing cachexia. For example, studies have shown that nutritional counseling with a dietician improved weight and quality of life for colorectal cancer and head and neck cancer survivors treated with radiotherapy. Also, any anti-cachexia program that aims to improve appetite, preserve muscle, and raise energy should be combined with an exercise program for the best results. A physical therapist can provide an individualized program of physical activity that is safe and focused on your needs. On the whole, your care team may include a physician, dietitian, physical therapist, and psychologist.
Are there any treatment options?
Scientific progress in understanding the mechanisms of cachexia has stimulated the discovery of promising new therapies. Although none of these therapies are yet approved by the FDA, they have shown encouraging results in clinical trials.
An oral drug that mimics the effects of ghrelin, our main appetite-stimulating hormone, was shown to improve appetite, weight, and muscle compared to placebo in a large international study. Other drugs showing promise in early trials include myostatin inhibitors, which are drugs that target a protein that decreases muscle size and growth.
In addition to these new therapies, older drugs, such as beta blockers, are being repurposed for treating cachexia. Beta blockers have been used to treat people with high blood pressure or heart failure for many decades. More recently, a preliminary, placebo-controlled trial found that a beta blocker improved muscle strength, muscle size, and weight in advanced colorectal cancer and lung cancer survivors.
When these new therapies complete final trials and demonstrate that they are both effective and safe, they could greatly benefit the estimated five million people in the United States coping with cachexia. However, any new anti-cachexia medication will still need to be combined with a multidisciplinary management approach that includes expert symptom control, an individualized exercise program, and dietary counseling.
Although there is increased awareness of cachexia’s impact on quality of life, cachexia is still under recognized by the medical community. So, you should alert your healthcare provider to any weight loss or decreased appetite you experience while undergoing cancer treatment. It’s important to address this condition as soon as possible so that it doesn’t interfere with your ability to continue cancer treatment.
Dr. Egidio Del Fabbro is an associate professor, Palliative Care Endowed Chair, and director of the palliative care program in the division of Hematology, Oncology, and Palliative Care at Virginia Commonwealth University in Richmond, VA.
This article was published in Coping® with Cancer magazine, May/June 2017.
