Features of silent acquired cytogenetic clones (SACC) after therapy and their clinicopathologic significance have not been well characterized.We investigated 15 cancer survivors treated for lymphoma who then developed SACC.Criteria to define SACC included: (1) the presence of clonality of ACC confirmed by cytogenetic methods; (2) no evidence of myeloid disease confirmed by bone marrow (BM) morphologic evaluation at the time of the occurrence of ACC; and (3) no clinical manifestations of secondary disease at the time of the occurrence of ACC.