Are most secondary acute lymphoblastic leukemias mixed acute leukemias?

A case of acute lymphoblastic leukemia (ALL) secondary to X-ray exposure is reported. The lymphoblasts expressed T-cell and myelomonocytic differentiation-related surface antigens. Clonal chromosomal abnormalities including t(2;12)(q25;q13),-10,der(10), del(11)(q14),der(12) and r were observed. A review of the cytogenetic data suggests that most secondary ALLs, with the exception of Burkitt type ALLs, may be biphenotypic or mixed acute leukemias.