[Nutritional assessment for cancer patient].

Weight loss and malnutrition is common in cancer patients, both origin of complications during the course of the disease. Although weight loss is predominantly due to loss of fat mass, the morbidity risk is given by the decrease in muscle mass. The causes of malnutrition are numerous, but the tumor cachexia and anorexia are the principals. The assessment of nutritional status is essential for a diagnosis of nutritional compromise and for the multidisciplinary management required. Subjective Global Assessment combines medical history, physical examination to classify patients as well nourished, moderately or severely malnourished. Subjective global assessment generated by the patient also includes nutritional symptoms and weight loss. Both instruments can serve as indicators of survival. The objective assessment, a significant weight loss (> 10%) for 6 months is considered an indicator of nutritional deficiency. BMI on the other hand has not proven to be a good indicator of malnutrition. Albumin and prealbumin, although widely used, should be used with caution. These are acute phase proteins, a situation that would alter specificity for diagnosis of visceral protein malnutrition. The bioelectrical impedance, in addition to determine body composition, has been linked to survival time and mortality. Although there are various methods, there is no "Gold Standard". The nutritional assessment instruments should be chosen according to the patient's condition.