Undernutrition is a state marked by energy and/or protein intake deficiency or mal-absorption, and is often described as protein energy malnutrition (PEM). Malnutrition is common in hospitalized patients worldwide. The prevalence of malnutrition in hospitalized patients range from 20% - 50%, depends on the varieties of diseases, health system, population and assessment tools. It is well documented in Western countries that malnutrition affects clinical outcomes negatively. Compared with well-nourished patients, patients with malnutrition stay longer in hospitals and related cost is significantly higher.

There is increasing evidence which indicates that appropriate nutrition support (e.g., standardized nutrition screening procedures, delivering nutrients with appropriate path, etc) may improve clinical outcome on malnutrition, along with cost saving.

To date, there is no study to document specifically the impact of malnutrition and related nutrition support on the health economics in China. Considering China now is on its way to establish public health security system and a diagnosis-related grouping system, the understanding of the cost effectiveness of nutrition support under the current clinical conditions is crucial.

This study aims to investigate the prevalence of perioperational malnutrition in gastroenterological cancer patient, the nutrition support status and related health economic effects.

Inclusion Criteria:

• Age 18 or older
• With gastroenterological cancer
• Will receive resectional operation
• Consent informed

Exclusion Criteria:

• With severly cardiac, pulmonary, liver or renal disease
• With endocrine or metabolic disease
• With dyslipidemia
• Without consent

Hospitalization patient in a teaching hospital