Many cancer patients lose weight during care. This makes it harder for their bodies to withstand the powerful treatments needed to fight the disease. Fortunately, there are steps patients can take to address the causes of cancer-related weight loss.
Cancer mouth sores and throat sores
Mouth and throat sores are the most common cause of cancer weight loss.
These sores are caused by chemotherapy drugs, which fight cancer by attacking rapidly dividing cells. Unfortunately, healthy cells that are supposed to divide rapidly are impacted by the treatment. These include cells that line the mouth and throat. As a result, many patients on chemotherapy develop painful sores in these areas, making it harder for them to eat.
Patients with mouth and throat sores should gargle four times a day with a mix of one tablespoon of salt and one tablespoon of baking soda in one cup of water. This rinse offers pain relief and helps prevent sores by cleaning the mouth.
Prescription mouthwashes that sooth the pain of these sores (but don’t prevent them) are also available.
Cancer and appetite loss
In some cases, chemotherapy affects a person’s appetite and sense of taste, making food unappealing. Even if they don’t want to eat, these patients should approach eating as a key part of their care and eat as much as they are able. If needed, they can be given medicines that actually increase their appetite.
Chemotherapy can also cause nausea, leaving patients less likely to eat. Fortunately, most patients’ nausea can be controlled with medication.
For some patients, appetite loss is caused by stress, anxiety, depression or similar factors. In these situations, patients should talk to their care teams about what they’re feeling. There are many ways to help patients manage these emotions, including medication, counseling and stress-management techniques.
Cancer and feeding tubes
Sometimes, patients are simply unable to maintain their weight, no matter how hard they try to eat or what steps they take to keep their weight up. This most often occurs in patients with advanced cancer. In these situations, patients may be given a feeding tube to supply them with calories and nutrients.
Whether it’s due to pain from a growing tumor, swallowing difficulties caused by radiation therapy, or the nausea, loss of appetite or mouth sores that are sometimes caused by chemotherapy, involuntary weight loss is a serious side effect of cancer and its treatment for many patients.
But there are other reasons that cancer patients could be losing weight without trying.
We spoke with internal medicine and palliative care specialist Rony Dev, D.O., to learn more about involuntary weight loss and what patients can do to counteract this common side effect. Here’s what he had to say.
What are the most common causes of involuntary weight loss in cancer patients?
The simplest answer is “decreased caloric intake.” They just aren’t eating as much. And when you don’t take in enough calories for your body to maintain itself, weight loss is the result. There are quite a few things that contribute to weight loss in addition to the underlying cancer.
For one thing, the body secretes inflammatory proteins, including “tumor necrosis factor” (TNF), which make people feel bad and typically experience a significant decrease in their appetite.
Trying to control cancer requires a lot of energy, too, and cancer patients’ metabolism is often elevated to accommodate for the increased inflammatory response. That combination alone is enough to cause weight loss, but when you combine it with the appetite-suppressing qualities of pain, changes in the taste of food (often described as being metallic) due to chemotherapy, and the discomfort caused by constipation and reflux issues, the issue of weight loss is often compounded.
Mood disorders, depression and anxiety can also contribute to weight loss. In addition, there are endocrine factors, such as low testosterone, that can cause changes in body composition and a decrease in weight in male patients with certain cancers or on chronic opioid therapy.
What can doctors do to help patients counteract involuntary weight loss?
Fortunately, there are treatments especially for symptoms that can contribute to weight loss. We can use beta-blockers to treat hypermetabolism; antiemetics for combatting nausea; counseling, anxiolytics (drugs used to treat anxiety) and antidepressants for stress and mood disorders; anti-inflammatories to reduce inflammation, and hormonal supplements to replace testosterone in male patients.
What can patients do to manage involuntary weight loss?
Most interventions require a health care provider, so it’s important to communicate with your care team as soon as you notice a problem. They can enlist the help of any specialists you might need, such as a dentist for tooth pain or chewing problems, and a gastroenterologist for help with bowel issues.
Why is it important for cancer patients to get unwanted weight loss under control quickly?
Patients tolerate cancer treatment better and have better responses to it if they can maintain a healthy weight. So, adequate caloric intake is critical to preventing chronic undernourishment.
Unwanted weight loss can also lead to fatigue, which means patients aren’t able to do all of the things they want to do. That causes a lot of distress — not only in patients, but also in their caregivers.
That’s why it’s so important to catch this problem early. So, if someone loses 5% or more of their total body weight without trying, that’s a big red flag. And we need to start addressing some of those underlying factors right away, before it snowballs.
Is involuntary weight loss more common in patients with certain types of cancers?
Yes. More than 80% of patients with pancreatic cancer will experience unwanted weight loss. It’s fairly common in other gastrointestinal cancers, too. And we’re also more likely to see it in advanced cancers, regardless of the type.
Are there any clinical trials underway related to involuntary weight loss?
Yes. One clinical trial is assessing psychological factors associated with weight loss. It deals with the frequency of cancer-induced anorexia (loss of appetite) and cachexia (wasting disease) in patients with anxiety and depression, and assesses body composition and takes other mitigating factors into account.
A second clinical trial is studying whether a drug called anamorelin can spur weight gain by manipulating the appetite hormone, ghrelin.
What’s the one thing you want cancer patients to know about involuntary weight loss?
Once dramatic weight loss has occurred, it’s very hard to change course. So seek help as soon as you notice it happening.
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