Holistic Evaluation of Approaches to Long-term Health & Survivorship

This study aims at investigating behaviors of cancer patient regarding complementary and alternative medicine (CAM) with mixed methodology. The investigators want to realize a pilot study evaluating patient's use and attitude with particular focus on natural products (phyto- and aromatherapy). They aim at giving an overview of their actual consumption (and not to promote natural products) in order to (1) prioritize needs regarding integrative care to promote quality of life and survivorship; (2) identify potential short- or medium-term safety issues for patients; and (3) propose adequate pharmaceutical council. Studied period (years): 2026, approximately 9 months * Date of first enrolment: to be determined * Date of last completed: to be determined Objectives: The study has three complementary objectives: Primary objective (quantitative): To descriptively quantify the use of complementary and alternative medicine (CAM) among cancer patients treated at Institut Jules Bordet and to identify patient-reported needs and information sources. Secondary objective (interventional mixed-methods) : To explore patient behaviors, perceptions and expectations regarding CAM use through questionnaires and semi-structured focus groups, including perceptions related to treatment adherence and survivorship experience. In addition, a structured medication review will be conducted for all participants in the focus group phase in order to identify and describe drug-related problems, including potential interactions between conventional treatments and herbal products. Operational objective : To support the prioritization and development of integrative oncology and survivorship programs within the ONCO.CARE and CAIROS projects. Hypotheses: No formal hypothesis testing is planned. This is an exploratory, descriptive study. Study Design (Treatment Schema): Prospective, single-center, two-phase study: * Phase 1: anonymous quantitative study based on a self-administered question