Characteristics and prognosis analysis of additional chromosome abnormalities in newly diagnosed acute promyelocytic leukemia treated with arsenic trioxide as the front-line therapy.

Currently, there are few studies that address the prognostic significance of baseline additional chromosomal abnormalities (ACAs) in newly diagnosed acute promyelocytic leukemia (APL) patients treated with arsenic trioxide (ATO) as the front-line therapy. A series of 271 consecutive APL patients has been cytogenetically investigated between 2004 and 2011 in our institution. The incidence of ACAs was 27% (46/172) in APL cases with t(15;17). Trisomy 8 was the most recurrent abnormality, accounting for 30% (14/46) of patients with ACAs, followed by +21 (7%, 3/46) and -7/7q (7%, 3/46). Nine cases (14.1%) were found to have additional balanced translocation aberrations, most of them are new and non-recurrent. Treatment protocols consisted of all-trans retinoic acid (ATRA) and chemotherapy with or without the ATO therapy. Overall, patients with and without ACAs had similar complete remission (CR) rates (94% and 98%, respectively, P=0.344). With a median follow-up of 41 months, univariate analysis showed that ACAs did not show any prognostic significance in relapse-free survival (RFS) and overall survival (OS). In addition, ATO treatment was an independent favorable predictor for RFS. Thus, this data provides insights into cytogenetic features of APL, and suggests that ATO-based combination therapy improved RFS in de novo APL patients, while ACAs had no impact on prognosis.