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

This is a prospective, single-center, single-arm Phase II study evaluating the efficacy of the myDIET software tool in the nutritional management of patients with localized and resectable esogastric junction cancer.

Gastric cancer is the 3rd leading cause of cancer mortality worldwide, with a 5-year survival rate of less than 30%. In localised gastric cancer (GC) or cancer of the oesogastric junction (OGJ), the standard treatment consists of gastrectomy and peri-operative FLOT-based chemotherapy (5FU, Leucovorin, Oxaliplatin, Taxotere). However, up to 51% of patients have post-operative complications, and only 60% can benefit from post-operative chemotherapy (at least one course) initiated within 12 weeks of surgery, while 46% receive the full theoretical regimen.

An incomplete adjuvant chemotherapy regimen drastically reduces post-operative prognosis. Undernutrition and sarcopenia increase the occurrence of post-operative complications, length of stay and post-operative readmissions. Undernutrition is an independent risk factor for failure and/or incomplete adjuvant chemotherapy, with an impact on progression-free survival and overall survival. There is a high prevalence of undernutrition in patients with GC/OGJ, estimated at 53-60%, and the proportion of undernourished patients increases significantly postoperatively compared with preoperatively.

Preoperative nutrition and physical activity in sarcopenic patients has been shown to reduce postoperative complications. Early multimodal management, combining nutrition, adapted physical activity and neoadjuvant chemotherapy, is therefore recommended and essential in the perioperative situation. To optimise the nutritional management of patients with operable gastric or oesogastric junction cancer, the CLB teams have developed a computer interface (MyDIET) linked to the myCLB patient portal. This provides semi-personalised monitoring based on self-questionnaires designed to assess and educate patients or their carers about nutritional issues from the outset of oncology treatment, and to prevent the onset or worsening of undernutrition.

For this reason, the sponsor proposes an exploratory study to assess the efficacy of the myDIET digital tool in increasing the proportion of patients with localised CG/OGJ initially treated with neo-adjuvant chemotherapy and who undergo surgery and are able to receive adjuvant chemotherapy within 8 weeks post-operatively.

Eligibility Criteria:
Inclusion Criteria:

* Patient 18 years of age or older at date of signing informed consent to participate;
* Histologically proven diagnosis of gastric adenocarcinoma or OGJ;
* Localized, resectable disease;
* Patient treated with perioperative Oxaliplatin-based chemotherapy,
* Performance status (ECOG): 0-2;
* Membership of a social security scheme;
* Signed informed consent to participate.

Exclusion Criteria:

* Other associated solid cancer or haemopathy;
* Presence of severe comorbidity (Charlson index \< 9)
* Presence of unbalanced dysthyroidism (TSH not within laboratory norm at inclusion, usually between 0.4 and 4 mUI/L);
* History of gastric, duodenal or esophageal surgery;
* Inability to comply with study requirements, including :

  * Impossibility for the patient or his/her caregiver to connect to myDIET;
  * Difficulty in understanding the written French language;
  * Psychological incapacity (e.g. excessive vulnerability, psychiatric disorder) or physical incapacity (e.g.

physical/motor disability);

* Patient under guardianship, curatorship or safeguard of justice;
* Patients already participating in a clinical trial or interventional study likely to interfere with the evaluation of the primary endpoint.