Malnutrition is a major challenge in cancer nutrition, affecting approximately 40% of cancer patients and having negative consequences on treatment efficacy, quality of life, and prognosis. It must be detected and managed early, based on clinical and laboratory criteria defined by the HAS recommendations.

To address this, several nutritional strategies are available, ranging from fortified oral feeding to artificial nutrition. Enteral nutrition, which is more physiological and carries fewer risks than parenteral nutrition, is recommended as the first-line treatment. Tools such as personalized care plans and guidelines help tailor patient care.

However, enteral nutrition remains underutilized in clinical practice, despite the recommendations. The ADHENUTE study, conducted at the Institut Curie, showed low compliance with recommendations (31%) and a tendency to favor oral nutritional supplements, even in severely malnourished patients. The lack of traceability of decisions makes it difficult to identify barriers, although patient refusal is sometimes mentioned.

To improve this situation, corrective measures have been implemented:

• for patients, through educational workshops to help them better understand and accept enteral nutrition;
• for healthcare providers, through training sessions to address reservations and enhance knowledge.

A third phase of the study aims to evaluate the impact of these actions, with the goal of increasing adherence to recommendations and the use of enteral nutrition.

The primary goal in cancer nutrition is to prevent, limit, and treat malnutrition. On average, 40% of cancer patients are malnourished (with this prevalence rising to as high as 90% depending on the cancer's location and the stage of the disease). Studies have shown that malnutrition reduces the effectiveness of cancer treatments, patients' quality of life, and their prognosis for recovery.

Screening for and management of malnutrition must be initiated early and based on the recommendations of the French National Authority for Health (HAS) in its guidelines titled "Diagnosis of Malnutrition in Children and Adults," updated in November 2020 and November 2021. In adults, the diagnosis of malnutrition (and its severity) is based on phenotypic and etiological criteria, including weight loss, Body Mass Index (BMI), albumin levels, and muscle strength measurements.

Dietary measures and interventions-ranging from optimizing oral intake to the use of Oral Nutritional Supplements (ONS) and Artificial Nutrition (AN)-help combat malnutrition. Enteral nutrition, which utilizes the digestive system, is the more physiological and effective solution, carrying a lower risk of infection. It is the preferred first-line treatment over parenteral nutrition.

Healthcare professionals can use the HAS's Personalized Care Plans (PPS) for oncology, which propose strategies based on treatment, age, and tumor location, as well as the phase of treatment (curative, initial palliative, advanced, or terminal). The nutritional care decision tree, which establishes a management strategy based on the patient's nutritional status and the severity of malnutrition-and is not specific to oncology-is a validated tool.

Despite the recommendations, the use of enteral nutrition remains insufficient. Indeed, and more broadly, this issue of non-compliance with recommendations for the implementation of enteral nutrition is commonly observed. This is confirmed by the study conducted by Defteros et al., which demonstrated that adhering to ESPEN (European Society for Clinical Nutrition and Metabolism) recommendations in clinical practice is difficult.

At the Institut Curie, until now, there has been little data on the extent to which recommendations for initiating enteral nutrition are followed.

We designed the ADHENUTE study (ADHEsion to Enteral Nutrition) to assess adherence to an enteral nutrition program in medical oncology and compliance with recommendations for implementing this nutritional support, both before and after corrective measures were implemented.

The study is designed in three phases:

> Phase 1: Verification of the hypothesis that enteral nutrition is under-used compared to recommendations, through a retrospective analysis of 200 medical records, and identification of barriers to the implementation of this nutritional support.

This phase was completed and highlighted in an article submitted to the *Bulletin du cancer* in March 2025, titled "Underutilization of enteral nutrition in medical oncology compared to recommendations." This initial phase revealed a compliance rate of 31% with the recommendations for enteral nutrition [95% CI: 20-42]. It also provided insight into which nutritional products were most frequently prescribed. A comparison between the recommended theoretical nutritional management and the management actually implemented in practice reveals a shift away from "enteral nutrition" toward "oral nutritional supplements." Furthermore, among the 189 usable records, 45% of patients were severely malnourished. Patients who received enteral nutrition generally had a poorer nutritional status than the overall study population: 21 out of 22 patients were malnourished (15 severely). However, the more severe the malnutrition, the more resistant it becomes to treatment, rendering dietary measures ineffective [10] and increasing the risk of complications during their implementation (notably an increased risk of inappropriate refeeding syndrome).

In their 2015 article [11], Coti-Bertrand et al. recommend tracking the indication for enteral nutrition as part of their criteria for evaluating and improving practices: "The indication for enteral nutrition is specified in the medical record." In the Adhénute study, documentation did not allow for the identification of the reason for non-compliance with enteral nutrition recommendations in each case. Among the records analyzed, the patient's refusal of enteral nutrition was mentioned in 5 records. For the 50 cases where enteral nutrition was not initiated despite recommendations to do so, this lack of traceability makes it impossible to determine why enteral nutrition was not provided.

• Step 2: Implementation of corrective measures for patients requiring enteral nutrition through an educational presentation of the project, and for healthcare providers and prescribing physicians through training sessions.

The proposal for corrective measures constitutes the second phase of the Adhénute project. These measures were implemented exclusively at the Saint Cloud site. The Paris site benefited from standard practices for improving clinical care.

They targeted two groups:

> Patients for whom enteral nutrition is indicated: The full report on best practices for dietary management in oncology regarding enteral nutrition [12] states that it is recommended to obtain the patient's consent through informed consent.

As part of Adhénute's corrective measures, enteral nutrition programs were presented to patients through educational initiatives such as Patient Therapeutic Education (PTE) workshops, with the aim of improving their understanding of this approach, reducing their level of apprehension, and increasing adherence to this nutritional method. This workshop, titled "I'm Committed to Enteral Nutrition," was designed for individual sessions or to include a caregiver and was offered to patients requiring enteral nutrition-whether in outpatient care or hospitalized-as soon as the need was identified (often on the same day, making it difficult to formalize the workshop into a full-fledged PTE program with a comprehensive pathway including BEPs). It includes 6 tools that can be adapted to the patient (material and nasogastric tube cards / keyword cards / food intake pie chart / choice method cards / arrows to associate with adverse effects / question-and-answer bubbles). The "emotions wheel" is used at the beginning and end of the workshop. An informational brochure is provided at the end of the workshop.

> Healthcare providers (doctors, nurses, nursing assistants). Training sessions were offered to medical and nursing staff.

The results of the first phase of Adhénute were presented to prescribing physicians, along with a review of the recommendations for implementing enteral nutrition during medical staff meetings in the target departments.

A training session titled "Overcoming Reluctance Toward Enteral Nutrition" was offered to medical and nursing teams in the target departments. Designed as a participatory and interactive ETP workshop, this training helped identify common barriers conveyed to patients by healthcare staff, enhance knowledge about this approach, and clarify the expected benefits for the patient.

This step has been completed

> Step 3: Evaluation of the impact of the improvement measures implemented in Step 2 To this end, a prospective analysis of patient records from those hospitalized in a medical oncology unit following the implementation of improvement measures will be conducted at the Saint-Cloud site. We expect to see an increase in the rate of compliance with recommendations as a result of these improvement measures.

Inclusion Criteria:

• Patients hospitalized (including those in the day hospital) in a medical oncology unit;
• Adults;
• Men or women;
• Patients for whom enteral nutrition is indicated according to SFNCM recommendations;

Exclusion Criteria:

• Minors (under 18 years of age)
• Patients receiving end-of-life palliative care
• Individuals deprived of their liberty or under legal guardianship (including conservatorship);
• Adults under judicial protection;
• Inability to participate in the study for geographical, social, or psychological reasons.
• Persons referred to in Articles L. 1121-5 through L. 1121-8 and L. 1122-1-2 of the Public Health Code (e.g., minors, adults under guardianship, etc.).
• Patients who do not speak or understand French.

We propose to conduct a prospective, single-center cohort study involving 80 patients. Patients will be enrolled at the Institut Curie in Saint Cloud over a 12-month period and followed for 6 months. Patients must be adults and hospitalized in a medical oncology ward.