Defining and characterising malnutrition and sarcopenia in patients undergoing oesophageal and gastric cancer surgery: a pilot observational study.

Condition observed 1. Malnutrition: baseline (before surgery) and 2 weeks, 6 weeks, 12 weeks, 6 months, and 12 months postoperatively. Assessment of malnutrition includes measuring body weight, body mass index (BMI), weight loss, muscle mass and dietary intake (3-day food diary). Muscle mass will be assessed using computed tomography (CT) when the images are taken at 3 time points for routine clinical purposes (initial diagnosis, preoperative restaging, and 12-month surveillance). Bioelectrical impedance spectroscopy (BIS) will also be used to measure muscle mass before surgery, and 2 weeks, 6 weeks, 12 weeks, 6 months, and 12 months after surgery. 2. Sarcopenia: baseline (before surgery) and 2 weeks, 6 weeks, 12 weeks, 6 months, and 12 months postoperatively. Sarcopenia diagnosis includes assessment of muscle strength (hand-grip strength dynamometer), muscle mass (CT or BIS body composition assessment), muscle quality or density (CT body composition assessment), and physical function (6-meter walk test). 3. Quality of life (QOL): baseline (before surgery) and 2 weeks, 6 weeks, 12 weeks, 6 months, and 12 months postoperatively. Assessed using the European Organisation for Research Treatment of Cancer (EORTC) quality of life questionnaire (QLQ-C30, version 3) and the oesophagogastric cancer specific module (EORTC QLQ-OG25). Additional information regarding the assessment of the above-mentioned conditions: 1. CT body composition analysis. The CT image used to assess body composition is those taken for routine clinical purposes at initial diagnosis, for restaging after chemotherapy and/or radiotherapy (this time point is before surgery) and at 12 months after surgery. This will take approximately 30-40 minutes to analyze the scan and obtain the results. Assessment of the CT image is done outside of the participant contact time. The CT body composition assessment is completed by a trained and competent dietitian, with supervision and assistance from a radiologist as required. A second trained dietitian will assess 10% of the CT images to determine inter-rater reliability. 2. Sarcopenia diagnosis. The three measurements required to diagnose sarcopenia are muscle mass (fat-free mass index using bioimpedance spectroscopy (BIS)), muscle strength (using hand-grip strength dynamometer), and physical function (using a 6-meter timed walk test). At each time point, these assessments will be carried out by a dietitian who is trained to operate and interpret the results from the BIS machine (no supervision is required). The assessments will take place in the surgical outpatient clinic rooms at Alfred Hospital. We anticipate that it may take up to 30 minutes to complete these assessments. 3. Questionnaires. The QOL surveys and 3-day food diaries are intended to be completed by the participant prior to their study appointment. On the occasion where the survey has not been completed, we estimate that it may take 15-20 minutes for the dietitian to complete them with the patient. Supervision is not required. Completion of the questionnaires will take place in the surgical outpatient clinic at The Alfred Hospital. Exposure Potentially curative surgical resection of oesophageal, gastric, or oesophagogastric junction cancer.