Study Evaluating the Efficacy of the myDIET Software Tool in the Nutritional Management of Patients With Localized and Resectable Gastric or Esogastric Junction Cancer.

proportion of patients for whom adjuvant treatment could be initiated within 2 months after surgery

Percentage of completed questionnaires

Number of supportive care and emergency consultations initiated by the caregiver on the bases of questionnaires completed by patients

Proportion of patients with malnutrition defined according to the criteria of the French National Authority for Health

Evolution of body composition based on body composition in L3 section on CT scan in volumes (cm2) at inclusion, after neoadjuvant treatment and 6 months after surgery.

Evolution of body composition based on body composition in L3 section on CT scan in indexes (cm2/m2) at inclusion, after neoadjuvant treatment and 6 months after surgery.

Changes in resting energy expenditure (Kcal/day) will be measured at inclusion, at day 5-12 postoperatively, and at 1 month after surgery (before adjuvant treatment) with the measurement of basal metabolic rate quantified by indirect calorimetry (Kcal/day)

The proportion of patients with dietary intakes > or equal to 30kcal/kg/day will be quantified during the dietary consultation at inclusion, at day 7 after surgery, at 1 month after surgery and 6 months after surgery.

Theoretical nutritional requirement and measurement of basal metabolic rate using indirect calorimetry (kcal/day) will be quantified during the dietary consultation at inclusion, at day 7 after surgery, at 1 month after surgery and 6 months after surgery.

Weight changes will be described by the weight in kg

Brachial circumference will be described in cm

Triceps skin fold will be described in mm

Initiation time for post-operative treatment will be defined as the time in days between the date of surgery and the date of the first course of post operative treatment

Proportion of patient with incomplete scheme of pre operative treatment and their causes will be described

Proportion of patient with incomplete scheme of post operative treatment and their causes will be described

Proportion of patients with severe post operative complication will be described according to the occurence of a grade > III complication according to Clavien Dindo classification

Tolerance to perioperative treatment will be assessed with self-assessment using myDIET questionnaires and nutritional consultations based on the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v5 classification.

Grades range from 1 to 5 and refer to the severity of the adverse event. A higher grade means a worse outcome.

Changes in food intake will be evaluated during treatment and the postoperative period (myDIET follow-up questionnaires).

Changes in SEFI (Easy Food Intake Score) will be evaluated using visual scales (during treatment and the postoperative period (myDIET follow-up questionnaires).

SEFIs are assessed using visual scales ('analogue' or 'portions eaten'). With the visual analogue scale, the patients indicate the quantities they are currently eating using the cursor on the graduated scale from "nothing at all" = 0 to "as usual" = 10.

With the visual portions eatenscale , patients can use the cursor to indicate the portions eaten at their last meal (lunch or dinner).

Quality of life will be assessed with European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). This 30-item questionnaire is completed by the patient and includes five multi-item functional scales (physical, role, cognitive, emotional and social); eight symptom scales (fatigue, pain, nausea and vomiting, dyspnoea, insomnia, loss of appetite and constipation); and a global health scale. The score for each item ranges from 1 (not at all) to 4 (very much).

The average lengh of hospital stay during surgery will be described in terms of the number of days spent in hospital

Recurrence free survival (RFS) will be definied as the duration in days between the date of inclusion and the date of radiologically documented relapse or death from any cause

Overall survival (OS) will be defined as the time in days from date of the inclusion to the date of death from any cause

Adherence to the physical activity program will be described by the number of weekly session declared by the patient

Physical activity levels will be assessed using the International Physical Activity Questionnaire (short version). The questions ask how much time the patient has spent being physically active over the last 7 days (duration of activity in minutes or hours, and number of days of activity in days).

Assessment of muscular function will be assessed by the 6-min walk test (described in meters)

Assessment of muscular function will be assessed by muscular strength measured with hand grip dynamometer (described in kg)

Assessment of muscular function will be assessed by the Five Times Sit to Stand Test (described in seconds)