TNFRSF17 and plasma cell myeloma: Given the patient was diagnosed with PBM with high Ki-67 and rapid progression after KD-DECP, which suggested she might not benefit from or tolerate further chemotherapy, and the fact that she refused ASCT, combined with the abundant BCMA expressions on her BM cells and the reported anti-myeloma effects of BCMA CAR-T cell therapy, our group decided to proceed with CAR-T as the next treatment option.