CD2 and acute promyelocytic leukemia: In an analysis of 114 APML cases, Brecciaet al. observed that the CD34/CD2-positive subgroup displayed several differential properties—including higher frequencies of M3v (27% versus 7%), bcr3 transcript subtype (73% versus 32%), higher incidence of DS (26% versus 12%), higher rate of relapse (66% versus 17%), and lower OS (88% versus 95%)—compared with CD34-negative patients23.