This is a long-term follow-up study for participants treated with Galapagos (GLPG) CAR T-cell therapies to evaluate the long-term safety and efficacy of GLPG CAR T-cell products for 15 years post infusion. Per Health Authorities guidelines for gene therapy medicinal products that utilize integrating vectors (e.g. lentiviral vectors), long term safety and efficacy follow up of treated patients is required. The purpose of this study is to monitor all participants exposed to GLPG CAR T-cell therapies for 15 years following their last CAR T-cell infusion to assess the risk of delayed adverse events (AEs) and the long-term benefit/risk profile and to monitor for replication-competent lentivirus (RCL) and CAR-T cell persistence.