Can Anorexia Be Caused By Cancer?

New cells are formed in the early stages of life to facilitate the growth of the body. Even when a person ceases to grow, the body is in dire need of new cells to replace the worn-out ones. All new cells formed result from the division of a pre-existing one. However, normal cells in the human body are programmed to multiply only a certain number of times and eventually face death. Cancer causes these cells to multiply uncontrollably. This unchecked cell-growth leads to the accumulation of a mass of cells called a tumor. 

The field of immunology has seen great advances. But, cancer research has been particularly challenging very since the inception of oncology as a science. Adding to the complexities, a number of cancer patients in the contemporary population show a weight-related response to the disease. From the aforementioned perception of cancer, it seems more likely that the disease would cause a gain of mass. So, cancer and anorexia should be opposite ends of the nutrition spectrum. But people with advanced stages of the disease are actually known to show symptoms of anorexia like fatigue and a lost appetite.

How is this caused?

This condition is referred to as the Cancer Anorexia Cachexia Syndrome (CACS). Cachexia is a medical term used to describe a collection of symptoms like muscle atrophy, loss of weight and weakness. CACS is a wasting disorder of the body resulting from malignancies of the gastrointestinal tract, pancreas, the thoracic region or the head and neck. It comes with poor prognosis which means that there are very less chances of the patient’s survival. There are almost no established treatments for this condition.

This syndrome can be caused due to a number of reasons

Changes caused by the tumor

Difficulties in swallowing caused by tumor formation can directly impinge gastrointestinal functions. A significant decline in food intake is also caused by tumor-derived substances like lactate. These disturb the normal metabolic cycles and are potent anorexic agents. Tumors alter nutrient distribution plans of the body and deprive other tissues of essential micronutrients like Zinc. Inflammation caused by these cancerous cells also induces the release of cytokines.

These effects lead to irregular secretions of hormones that help the body regulate appetite thus resulting in food restriction.

Central causes

The modulation of various nutrients in turn affects the transmission cascades of the central nervous system. This might lead to conditions like depression and chronic pain thus altering eating habits.

Effects of treatments like Chemotherapy can also contribute to causing CACS.

Symptoms and diagnosis of CACS

Not everybody who has this syndrome looks malnourished. This is because the person could have been overweight before CACS became a chronic illness for him. Hence, there are a few clinical assessments to determine if a person is actually a victim of this disorder.

·        The person has lost over 5% of his body weight unintentionally

·        BMI < 20 in a person less than 65 years old
BMI < 20 in a person 65 years or older

·        Body fat is less than 10%

·        An increased level of cytokines in the blood (resulting from inflammation)

·        Serum albumin level < 35 g/L

People with this syndrome might not respond equally well to treatments of cancer.  A high percentage of people with these advanced cancers are known to show bone metastasis i.e. relocation of cancerous cells to the bone. Their immunity can be lowered further and they hence experience a highly diminished quality of life.

Management of the disorder

The cancer supportive care landscape has been widening with robust drug development as summarized in the GBI Research report, “Cancer Supportive Care Drug Development Pipeline Review,2017”. There are a number of ways in which CACS can be managed:

·         Appetite stimulants

The positives of dietary counseling from trained experts haven’t been demonstrated. Appetite stimulants like corticosteroids or progestational agents have a greater impact. They have shown to increase the patient’s appetite in a few cases but do not have a long lasting effect. 

·         Enteral and parenteral nutrition

Administration of food directly through the gastrointestinal tract of through intravenous injections can be employed. However, this has been extensively studied and has only shown to have the required effect in rare cases. 

·         Muscle building

If the person still has the ability to exercise, he can take up to resistance training to build muscles.

All these efforts are rarely enough to reverse the effects of CACS. Since this syndrome is a secondary disorder resulting from cancer, treatment of that should be in focus. CACS has no established treatment regimens. It causes great emotional stress not only on the patients but also the family members and close acquaintances. Patients are usually forced to consume more calories in the hope that this will help them live longer. This isn’t always of much clinical benefit. Only compassion and care can help their struggle for survival in the final stages of their life.