Cancer cachexia appears to be caused by chemicals given off by the tumor or by the patient's immune system that is trying to combat the tumor.

CNN: Is the inability of cancer patients to eat a concern?

Oncologists generally agree that the actual cause of death in cancer patients is cachexia, a condition of severe weight loss and wasting associated with protein mal-absorption.

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When there is effective treatment of the cancer, symptoms of cachexia decrease.

CNN: Is the inability of cancer patients to eat a concern?

Cachexia is best known as a disease of cancer patients, but it is seen in patients with chronic infection, AIDS, heart failure, rheumatoid diseases and chronic obstructive pulmonary disease.

CNN: Is the inability of cancer patients to eat a concern?

Studies demonstrate that cachexia is the direct cause of death in a small number of cancer patients (1 to 2 percent).

CNN: Is the inability of cancer patients to eat a concern?

Nearly half of patients with cancer that has spread to organs other the original site of disease (metastatic disease) have cachexia.

CNN: Is the inability of cancer patients to eat a concern?