15;17 Translocation in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a relatively rare subtype of leukemia that has been reported to be associated with a specific chromosome abnormality, t(15;17). It has been suggested that this translocation may have a geographical distribution and its presence may signify a poorer prognosis. In this present series of 14 patients with APL, 9 patients (64%) had the t(15;17) and 5 did not; however, no significant differences in clinical features or outcome could be found between those who did and those who did not express the translocation. When ethnic backgrounds were explored, no differences were found. More cases of the t(15;17) were found in recent years (7 of 8 patients studied since 1978 compared to 2 of 6 before 1978). This corresponded to changes made in our cytogenetic techniques suggesting that the finding of the t(15;17) may be a function of technique, rather than a real difference in disease entities, and all patients with APL may have the t(15;17) when appropriately studied.