However, more than three million Americans who were diagnosed with the disease five or more years ago are still alive today because of improved methods of detection and treatment. Cachexia, a combination of malnutrition and weight loss, is a common problem associated with cancer. Both treatment and the effects of the disease can decrease appetite and food intake or interfere with the digestion, absorption or utilization of food by the body. Researchers estimate that cancer cachexia syndrome may be responsible for two thirds of cancer-related deaths. Depending on the type of cancer, malnutrition may result from anorexia, impaired food intake or digestion due to tumor obstruction or malabsorption in the gastrointestinal tract.
Many patients develop nutritional problems due to the local effects of specific cancers.
For example, brain and head tumors may make it difficult to chew and swallow, while colon tumors may cause abnormal digestion or absorption. The three major forms of therapy used to treat cancer today are surgery, chemotherapy and radiation therapy. These treatments can often result in impaired nutrition. For example, surgical procedures involving head or neck tumors may alter the patient's ability to chew or swallow. Radiation therapy can produce an inflammation of the normal tissues surrounding treatment areas and may result in altered taste sensations, difficulty in chewing and swallowing, anorexia, nausea and diarrhea.