IKZF1plus alterations are not associated with outcomes in Philadelphia-positive acute lymphoblastic leukemia patients enrolled in the FBMTG ALL/MRD2008 trial.

ABSTRACT

OBJECTIVE: The prognostic significance of IKZF1plus in adult Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) patients had remained to be clarified. METHODS: We conducted a prospective, multicenter study, the ALL/MRD2008 trial, and investigated the clinical significance of IKZF1plus . RESULTS: From December 2008 to November 2013, 38 untreated Ph+ ALL patients were enrolled. At the end of the induction, 97.4% of patients (37/38) achieved complete hematological remission, with MRD-negativity of 48.6% (18/37). There were 19 patients with IKZF1plus , 13 with IKZF1 deletion alone (ΔIKZF1) and 4 with no IKZF1 deletions (no ΔIKZF1). The probability of 3-year DFS and OS in these Ph+ ALL patients were 50% (95% confidence interval [CI], 33-65) and 55% (95% CI, 38-69), respectively. There was no significant difference between IKZF1plus , ΔIKZF1, and no ΔIKZF1 in DFS (47%, 54%, 75% [p = .63]) or OS (47%, 62%, NA [p = .39]). CONCLUSIONS: We revealed no relationship between IKZF1plus status and survival outcomes in Ph+ ALL patients treated with imatinib/dasatinib combination chemotherapy. Further investigations are warranted to clarify the prognostic significance of IKZF1plus in adult Ph+ ALL patients.