57 Assessment of the spatial distribution of B cells subpopulations in the tumor microenvironment and tertiary lymphoid structures by Brightplex®, a sequential chromogenic multiple... by Jerome Galon, Aurelie Collignon, Alex Trinh, Marion Olive, Clémence Jaume, Maïté Chamourin, Nour Sfeir, Dylan Anselmo, Raana Ramouz-Charpentier, Georgia Culey, Christophe Haond, Jacques Fieschi-Meric