Background: ABL and AUL are associated with an unfavourable outcome for patients (pts) treated with standard-dose therapy alone. Although high-dose therapy has been used successfully in this population, the optimal management of pts with ABL/AUL remains unclear.

Methods: A retrospective review was performed involving 24 adult pts with ABL or AUL who were treated in Vancouver between 1984 and 2006. Kaplan-Meier estimates were utilized for event-free survival (EFS) and overall survival (OAS) and a multivariate analysis was performed to determine factors predictive of outcome.

Characteristics: Utilizing the WHO criteria, 18 pts had ABL and 6 pts had AUL. There were 17 males and 7 females with a median age of 37 (range 22–75) years. Median white cell count (WCC) at presentation was 10.1 × 109(range: 0.9–196 × 109)/L. Seven pts had poor-risk karyotypes (3 pts complex, 3 pts with t(9,22), 2 pts with11q23 rearrangement, and 1 pt with monosomy 7),12 pts had standard-risk karyotypes, and 5 pts had an unknown karyotype. Induction chemotherapy consisted of Cytosine arabinoside (3–6/m2/day), Daunorubicin, Vincristine and Prednisone with one pt with t(9,22) also having received Imatinib Mesylate. Thirteen pts went on to receive high-dose therapy and SCT. Stem cell source was autologous in 3 pts (all with AUL) or a related (6 pts) or an unrelated donor (4 pts). Eight of 10 pts were in complete remission at the time of SCT, one was in relapse and one had primary refractory ABL. Conditioning was TBI-based in 10 pts and Busulfan-based in 3 pts.

Results: EFS and OAS estimates for all 24 patients at 3 years were 25% (95% CI 13%–50%) and 32% (95% CI 17%–58%), respectively. The non-relapse mortality (NRM) for the whole group at 3 years was 43% (95%CI 15%–61%). On multivariate analysis, when compared to pts receiving only standard-dose chemotherapy, pts who underwent high-dose therapy had significantly improved EFS [39% (95% CI 19%–77%) vs. 9% (95% CI 1%–59%), p=.03] and OAS [46% (95% CI 26%–83%) vs.14% (95% CI 3–74%), p=0.01], respectively. Age, WCC at presentation and cytogenetic risk group were not found to significantly influence outcome.

Conclusion: Although patient numbers are limited, this experience would suggest that patients with ABL/AUL who achieve complete remission with standard chemotherapy should be considered for high-dose therapy and stem cell transplantation. This approach provides them with the greatest probability of long-term event- free and overall survival.

Disclosure: No relevant conflicts of interest to declare.