We report 14 cases of immune effector cell (IEC)-associated enterocolitis following chimeric antigen receptor T-cell (CAR-T) therapy in multiple myeloma, with a 1.2% incidence overall (0.2% for idecabtagene vicleucel and 2.2% for ciltacabtagene autoleucel). Patients developed acute-onset symptoms (typically non-bloody Grade 3+ diarrhea) with negative infectious workup beginning a median of 92.5 days (range: 22-210 days) after CAR-T therapy and a median of 85 days after cytokine release …