Nutritional status in relation to treatment modalities

The prevalence of disease-related malnutrition in patients with cancer ranges from 40% to 80%, which is the highest of all hospital groups. This variation in prevalence is the result of the different definitions of malnutrition used, and it also depends on tumour type, stage and anticancer treatment. Malnutrition is associated with negative outcome, including increased morbidity, poor prognoses and tolerance to treatment, decreased quality of life and increased health-care costs [1]. Head and neck cancer patients who experience a weight loss >20% of their total body weight during or following radiotherapy are at an increased risk of toxicity and mortality. Stage 3 or 4 disease and smoking more than 20 cigarettes a day should be reason enough for early enteral feeding. A prophylactic percutaneously placed endoscopic gastrostomy (PEG) feeding tube is also beneficial when there is pretreatment weight loss [2]. Nutrition screening is the process of identifying patients with characteristics commonly associated with nutritional problems that may require full nutritional assessment. Screening can be applied to all patients. The malnutrition screening tool (MST) is a validated, quick and simple nutrition screening tool. The patient-generated subjective global assessment (PG-SGA) can be applied for a full nutritional assessment [1]. The identification of baseline risk factors to assess a patient’s fragility or ability to tolerate treatment is desirable to predict outcome of chemotherapy toxicity, not only for medically unfit patients but also amongst patients with an apparently good medical condition, since the high inter-individual variability in drug exposure remains an unresolved issue. Chemotherapy-induced DNA damage might become more cytotoxic to normal tissue in the presence of perturbations of the cellular immune response because of high protein catabolism and stimulation of acute-phase protein responses (APPRs). The nutritional and inflammatory status (NIS) appears to correlate with increased risk of severe haematological toxicity following anticancer chemotherapy. This status takes in account (1) C-reactive protein, (2) alpha-1-acid glycoprotein, (3) albumin and (4) prealbumin: NIS = (1 · 2)/ (3 · 4) [3]. Malnutrition has been associated with changes in drug disposition, including changes in absorption, protein binding, hepatic metabolism and renal elimination. In malnourished patients reduced concentrations of plasma proteins may significantly increase the likelihood of toxicity from the administrations of agents that are highly protein-bound, such as prednisolone, etoposide, teniposide, cisplatin, paclitaxel and SN-38 [4]. Anticancer treatment can induce a poor nutritional status by inducing nausea, vomiting and anorexia and gastrointestinal disorders as mucositis and diarrhoea [4]. Reversible lactose intolerance – associated with diarrhoea, flatulence and poor nutritional status – is not infrequent in patients treated with chemotherapy based on 5-fluorouracil (5-FU). Hypolactasia can easily be diagnosed with a lactose tolerance test. Dietary lactose restriction might improve tolerability of treatment [5]. Malabsorption may be caused not only by fluorouracil but also by other drugs affecting cell proliferation such as thioguanine, methotrexate, vinca’s alkaloid, actinomycin D, hydroxyurea and daunomycin [6].