Palliative care in day-hospital for advanced cancer patients: a study protocol for a multicentre randomized controlled trial oleh Laura Thery, Amélie Anota, Lorraine Waechter, Celine Laouisset, Timothee Marchal, Alexis Burnod, Elisabeth Angellier, Oum El Kheir Djoumakh, Clemence Thebaut, Anne Brédart, Sylvie Dolbeault, Jean-Christophe Mino, Carole Bouleuc