POP-UP: a Single-arm, Two-cohort Study: an 8-week Trimodal Pre-habilitation Program for Patients With Pancreatic Ductal Adenocarcinoma and Oesogastric

The POP-UP study aims to evaluate the feasibility of an 8-week trimodal pre/posthabilitation program (consisting of APA, nutritional assessment, and psychological support) with remote monitoring of the APA sessions and nurse coordination alongside perioperative triplet chemotherapy in patients with localized PDAC (resectable or borderline resectable tumor) or OGC (≥ cT2 or N+). The prehabilitation program will be conducted during neoadjuvant chemotherapy and the 3-5 weeks prior to surgery for a total of 8 weeks before surgery. There will be a total of three prehabilitation hospital days during the prehabilitation program. The preoperative prehabilitation will include: * Once per month, a prehabilitation hospital-day with functional capacities assessment with validated tests made by a physiotherapist or an APA professional (according of center resources/functioning), medical and nurse assessment evaluating performance status, chemotherapy toxicity and tolerance, and nutritional assessment (according to the functioning of each center it will be made by these professionals -with university training on nutrition- or a dietician). A therapeutic training session on the adherence to the prehabilitation program will be done by the nurse (trained in therapeutic education). * Weekly, an APA professional trainer will follow via using app (Activiti®) the APA home-based program. It will be based on the functional capacities assessment made during the prehabilitation hospital day. The exercise training program will consist of twice per week autonomy sessions, supervised and adapted by the APA professional, and once per week a guided session with the APA professional. The patient will have a total of 3 physical activity sessions per week. * Once per week, the nurse practitioner (or case manager, according to center functioning) will evaluate the patient via a videoconference to assess the chemotherapy toxicity and tolerance and patient's weight modifications. The posthabilitation program will start for a total of 8 weeks, one week after surgery discharge. The structure is the same as the prehabilitation program except for the follow of chemotherapy toxicity and tolerance that will be replaced by the follow of the surgical complications/consequences. There will be a total of three posthabilitation days at hospital during the posthabilitation program.