[Consequences of a comorbidity often neglected in oncology: malnutrition]

Malnutrition is a common problem in patients with cancer, with a prevalence ranging between 30 and 80%, depending on the criteria used to determine malnutrition and patient characteristics. Malnutrition is a major cause of morbidity and mortality in cancer patients. It is associated with functional impairment, as well as poor outcome and quality of life. The impact on morbidity is persistent, with increased susceptibility to treatment-related adverse events, infection and postoperative complications. Significant weight loss is generally associated with higher mortality, possibly because it makes it impossible to administer the optimal therapeutic program in order to stabilize or cure the disease, in particular because of the patient's poor clinical condition or of increased treatment toxicity. In late stage patients, cachexia can be a direct cause of death. Studies have shown that direct or indirect complications of clinical malnutrition have economic implications; the number and length of hospital stays, as well as treatment and managements costs, are significantly increased in malnourished patients. Since the risk of hospital malnutrition can no longer be ignored, early nutritional assessment at the time of cancer diagnosis is mandatory in order to initiate timely nutritional therapy.