T-cell acute lymphoblastic leukemia with translocation (1;18)

A case of T-cell acute lymphoblastic leukemia with a translocation between chromosomes #1 and #18 is described. The breakpoints were at bands 1q23 and 18q21. A single cell contained the translocation t(1;19)(q23;p13). The breakpoint on chromosome #1 was the same in both translocations, and the breakpoint on chromosome #18 was the same as that in t(14;18)(q32;q21) associated with follicular lymphoma. The possible relationship between chromosome bands 1q23 and 18q21 and the morphologic features of the leukemia cells is discussed.