An eight-way variant t(15;17) in acute promyelocytic leukemia elucidated using fluorescence in situ hybridization

A complex eight-way translocation was identified, with the aid of fluorescence in situ hybridization (FISH), in a patient diagnosed as having acute promyelocytic leukemia (APL). The balanced translocation was defined as 46,XY,t(1;6;7;6;17;15;12;3) (p22;q27;p15;q13;q21;q22;q13;p13), which includes a der(15) chromosome consistent with the der(15) chromosome of the t(15;17)(q22;q21) typically found in APL. The patient was treated with all-trans retinoic acid (ATRA) and had a clinical course typical of the disease, which is currently in remission after an autologous bone marrow transplant. The other structural rearrangements appeared to have little effect on the biology of the neoplasia.