Malnutrition in the Oncology patient
Malnutrition is common in oncology patients.
Unintentional weight loss and malnutrition are very common during cancer.
The location and extent of the tumour are directly involved in the development of nutritional deterioration. The causes of malnutrition are classified into those related to the tumour itself, to the patient, or to oncological treatments.
Four main mechanisms through which malnutrition may occur in cancer patients can be distinguished: insufficient intake of energy and nutrients, alterations in the digestion and/or absorption of nutrients, increased nutritional requirements, and alterations in nutrient metabolism.
The consequences of malnutrition on the prognosis of the oncology patient manifest at both functional and structural levels, affecting clinical progression, adherence to treatment, and the psychosocial sphere.
The effectiveness of chemotherapy and radiotherapy is reduced, the risk of toxicity from these treatments increases, muscle mass and functional capacity decrease, the risk of postoperative complications rises, hospital stays are prolonged, and quality of life worsens, which in turn leads to higher economic costs. In addition, weight loss is associated with reduced survival. Tumour cachexia predicts a poor response to oncological treatment.
The most significant nutritional deficiency is protein–energy malnutrition (kwashiorkor), in addition to nutritional depletion of vitamins and trace elements.
Weight deficit may be present or may vary depending on oedema. Malnutrition occurs more frequently in cancers of the lung, head and neck, prostate, stomach and pancreas. Therefore, the nutrition of oncology patients should be considered an essential part of the overall assessment from the moment of diagnosis.
With the aim of treating malnutrition associated with the patient, extensive scientific evidence demonstrates the effectiveness of nutritional supplements in the management of oncology patients who are malnourished or at risk of malnutrition.
The use of nutritional supplementation in this type of patient helps to prevent nutritional deficiencies or correct them when they occur in the form of loss of lean body mass, improve immune status, contribute to better tolerance of antineoplastic treatment, reduce the risk of surgical complications, help decrease hospital admissions, and improve the patient’s functional status and quality of life.