Abbreviations: ARA-C = cytosine arabinoside; ATG = antithymocyte globulins; Bu = busulfan; Clo = clofarabine; Cy = cyclophosphamide; Flu = fludarabine; Mel = melphalan.

While some patients with high-risk acute myeloid leukemia (AML) require one or two cycles of induction chemotherapy to achieve a complete remission (CR), others require more than two cycles. We examined the outcomes of patients with high-risk AML who received allogeneic HPC transplant in CR1. Forty five consecutive high-risk AML patients in CR1 were included. All 45 patients had adverse cytogenetics, FLT 3 mutations, or secondary AML. Group A patients (n 5 33) received one or two cycles, and Group B (n 5 12) three or more cycles of induction chemotherapy. The patients were comparable in age, sex, white cell count at presentation, and time from diagnosis and from last chemotherapy to transplant. The 100-day mortality rate was higher in Group B patients (50% vs. 9%, P 5 0.006). They had a higher non-relapse mortality (33% vs. 6%, P 5 0.035) and a longer length of hospital stay from the day of stem cell infusion (median 21 vs. 20, P 5 0.02; third quartile 22 vs. 28, P 5 0.02). There was also a trend toward inferior event-free survival and overall survival. High-risk AML patients undergoing allogeneic transplant in CR1 after three or more cycles of induction chemotherapy have an inferior outcome and higher mortality when compared to those who only needed one or two cycles of induction chemotherapy. Novel strategies are needed to reduce the transplant-related mortality in high-risk AML patients needing more than two cycles of induction chemotherapy prior to allogeneic transplant in CR1.

Pulmonary nodules (PNs) develop frequently in patients with acute myeloid leukemia (AML). They are of infectious or inflammatory origin. They pose potential challenges to successful hematopoietic progenitor cell (HPC) transplant as they may be niches for infection reactivation or sites susceptible to subsequent infections. We retrospectively analyzed the outcome of 20 AML patients with multiple PNs who underwent allogeneic HPC transplants (12 related, 8 unrelated). There were 13 males and seven females (median age 52 yrs). Nine patients were in CR1, seven in CR2, and four with residual disease. The median times from appearance of PNs and from last positive CT scans to transplant were three and two months, respectively. The median time from pretransplant CT scans to transplant was one month. Multiple PNs were still reported in 5/20 of the pretransplant scans. The PNs in all five patients did not worsen after transplant. Four patients (one with positive pretransplant CT scan) died within the first 100 d after transplant, but none from primary pulmonary pathology. The median survival of this group of patients was 350 d. Our results, therefore, suggest that multiple PNs of uncertain etiology in patients with AML do not impact adversely on the outcome of allogeneic HPC transplant.