CD276 and rhabdomyosarcoma: We have shown that 74% of NB, 67% of rhabdomyosarcomas and 100% of medulloblastomas were stained by the 5B14 mAb, which recognizes the B7-H3 molecule.9 Conversely, 100% of lymphoblastic lymphomas and the blastemic component of Wilms’ tumours were completely negative.