A B S T R A C TPatients with gastrointestinal cancer and malnutrition are less likely to tolerate major surgical procedures, radiotherapy or chemotherapy.In general, they display a higher incidence of complications such as infection, dehiscence and sepsis, which increases the length of stay and risk of death, and reduces quality of life. The aim of this review is to discuss the pros and cons of different points of view to assess nutritional risk in patients with gastrointestinal tract (GIT) tumors and their viability, considering the current understanding and screening approaches in the field. A better combination of anthropometric, laboratory and subjective evaluations is needed in patients with GIT cancer, since malnutrition in these patients is usually much more severe than in those patients with tumors at sites other than the GIT. Therefore, in the daily practice of oncology, the definition of an appreciable and simple to apply nutritional assessment tool is necessary to identify nutritional risk patients and thus determine the best approach and appropriate nutritional support 8 . The objective of this review is to present an overview of the methods and tools used to determine nutritional risk, considering the pros and cons when applied to patients with GIT cancer.
METHODSWe systematically identified studies on nutritional status of patients with GIT cancer through the PubMed and MEDLINE databases. We researched articles published in the last ten years by combining the terms "nutritional assessment", "GI cancer", "gastrointestinal tract", "gastric cancer", "oesophageal cancer" and "pancreatic cancer". We considered for evaluation only complete articles with those terms in English or Portuguese. We identified additional articles from citations in the articles evaluated.
RESULTS AND DISCUSSION
General review of nutritional assessmentIt was in the 1950s that authors first published research related to nutritional assessment procedures.
Subjective methodsIn 1980, Detsky et al. described the Subjective Global Assessment (SGA) used to assess preoperative patients with GIT tumors (n = 202) undergoing major surgical procedures; They have shown that SGA could be easily applied and considered it a valid and reliable method to estimate the surgical patients' nutritional status 12 .Other authors have published several articles supporting the SGA in determining nutritional status, which differed from other methods in considering not only changes in body composition, but also functional changes. In addition, SGA is a simple, inexpensive, non-invasive method and can be performed at bedside.Correct guidance on the SGA application is essential, since its accuracy depends on the observer's ability to detect subjectively significant nutritional changes 8,13,14 .Subsequently, the SGA has undergone modi- Wu et al. had higher incidence of complications and longer hospital stay the worse the level of SGA in patients undergoing major procedures for GIT cancer (mainly gastric) 18 . These results were also supported by our series o...