Transplantation outcomes in Philadelphia-positive acute lymphoblastic leukemia with additional cytogenetic abnormalities: A study on behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

We compared the presence of additional chromosomal abnormalities (ACAs, n = 345) with a referent group with no ACAs (n = 169) (noACAs) in patients with Ph+ ALL receiving TKI before transplantation. The groups did not differ significantly in age, gender, or interval from diagnosis to transplantation. More patients with ACAs received PB grafts (86.4% vs. 78.1%, p = 0.03), while more patients in the noACAs group received myeloablative conditioning (87% vs. 75.9%, p = 0.003). Day 30 ANC (≥109/L) was 97.9% vs. 98.2%, and day 60 platelet count (≥20 × 109/L) was 93.9% vs. 95.5%. Day 100 acute GVHD grades II-IV was 26.4% vs. 31%, and of grades III-IV was 8.6% vs. 9.7%. 4-year chronic GVHD was 40.5% vs. 39.9%, and the proportion of extensive chronic GVHD was 19.3% vs. 20.1%. 4-year NRM was 13.1% vs. 13.5%, and 4-year RI was 19.2% vs. 21.1%; 4-year LFS and OS were 67.7% vs. 65.4% and 76.3% vs. 78.5%. 4-year GRFS was 48.5% vs. 45%, respectively. In multivariable analysis, having ACAs and the number of ACAs did not significantly affect transplant outcomes. Administration of a TKI upfront, followed by transplantation, may overcome the poor prognostic influence of ACAs in Ph+ ALL.