**3. ASCT for acute promyelocytic leukemia**

*Acute Leukemias*

group (4% vs. 1% respectively).

observed after RIC alloHSCT.

negative upon induction chemotherapy [26].

Several historical randomized trials have reported that ASCT can significantly reduce the relapse rates compare with conventional chemotherapy alone. The study performed by the Dutch–Belgian Hemato-Oncology Cooperative Group/Swiss Group for Clinical Cancer Research (HOVON-SAKK) Cooperative Consortium compared the outcomes of ASCT with chemotherapy including 517 patients who were randomly recorded between 1995 and 2006 [1]. Rates of relapse after chemotherapy vs. after ASCT were 70% vs. 58%, respectively (*P* = .02), 5 year follow up and no significant difference in LFS of 29% vs. 38% (*P* = .065). OS did not differ between these two groups and was estimated to be 41% vs. 44%, respectively, at 5 years from randomization. TRM was higher in ASCT group than chemotherapy

A meta-analysis which included 11 studies compared survival outcomes of alloSCT from matched sibling donor (MSD) or matched unrelated donor (MUD) versus ASCT in intermediate-risk AML and demonstrated alloSCT from MSDs rather than MUDs was associated with better OS than that with ASCT [13] however recent retrospective trials reported similar survival rates for AML patients who

The treatment options are not well defined in older patients with leukemia. Higher incidence of AML secondary to previous myelodysplastic syndrome (MDS), adverse mutation pattern and karyotype and poor performance status are the reasons of poor outcomes in older AML patients [16–18]. They usually do not have MSD and available regimens are limited due to many of comorbidities especially cardiovasculary disease. ASCT may be used in patients up to age 70 years with an acceptable TRM of approximately 8%, which compares favorably to 17% as was

Several reports from EBMT and CIBMTR showed long-term leukemia free survival (LFS) rates are 45–55% in patients transplanted in CR 1 and 25–35% for those transplanted in CR2 [19–21]. The patients who are not eligible for Allo-SCT ASCT may be an acceptable post-remission therapy in CR1 [14]. Allo-SCT still remains first line treatment for poor risk patients while ASCT is getting attention for good risk and especially intermediate risk patients who have favorable prognostic factors, including MRD negativity after the imitation of induction chemotherapy, a WBC count of <20,000/μL at time of the diagnosis, an FAB classification of M1–5, and ≥ 50% MPO positivity. Decision-making might benefit from taking minimal residual disease (MRD) into account [22, 23]. Real-time quantitative PCR (qPCR) and multiparameter flow cytometry (MFC) are effective techniques for monitoring MRD before and after ASCT in patients with AML, and MRD status pre-ASCT is an independent prognostic factor for both OS and LFS after ASCT [24, 25]. Whereby MRD-negative patients may be consolidated by ASCT and MRD-positive patients may proceed to allo-SCT. ASCT is generating new interest, especially in intermediate-risk patients who became MRD

The traditional conditioning regimens before ASCT that are mostly myeloablative and based on busulfan; combination of busulfan/ cyclophosphamide (BUCY), busulfan/etoposide, cyclophosphamide/Total body irradiation (TBI), Busulfan/ high dose melphalan. Different regimens such as modifications of the BCNU, etoposide, cytarabine, melphalan (BEAM) regimen, busulfan/etoposide/ cytarabine, TBI/cytarabine/melphalan could be used in different centers. Three large retrospective studies showed that busulfan/high dose melphalan regimen has better outcomes than BUCY [27–29]. Although both oral and intravenous busulfan were used in various regimens, it has become clear that the intravenous administration of busulfan should be preferred because of fewer complications [30]. Favorable longterm LFS after auto-SCT using a high-dose cytarabine-containing regimen has been showed. The most common treatment related complication of ASCT is mucositis

underwent autoSCT and allo-SCT from MSDs and MUDs [3, 14, 15].

**212**

Acute promyelocytic leukemia (APL) accounts 10–15% of AML in adults. It is highly curable disease and remission is achieved in 90% of APL patients after anthracycline-based induction therapy plus ATRA and recently arsenic trioxide (ATO). The combination of ATRA and anthracyclines remains the gold standard for high risk patients. There is not a role for stem cell transplantation in APL in CR1, independently from any initial risk category. ELN suggested that patients who relapsed after ATRA plus chemotherapy should be treated with an ATRA plus ATO based approach as salvage therapy until achievement of MRD negativity. Despite of SCT is accepted treatment for the 10–20% patients who relapsed, the choice of ASCT vs. Allo-SCT remains controversial.

EBMT reviewed 625 APL patients transplanted ASCT or Allo-SCT, lower relapse rates and higher 5 year LFS reported in Allo-SCT group. Although TRM was higher in Allo-SCT patients, Allo-SCT was recommended in CR2 when a sibling donor was available in this study [31]. Holter et al. reported OS was better after ASCT than after chemotherapy and ATO. ASCT was the preferred therapy for patients with CR2 status, and survival outcomes were superior in patients who received ASCT compared with those who received ATO-based consolidation therapy [32]. Besides ASCT is superior than allo-SCT in relapsed APL due to low TRM and durable remission, pre-SCT bone marrow cytogenetic and molecularly evaluation is important. It was recommended allogeneic HCT if the pre-HCT marrow was cytogenetically or molecularly positive [33]. ASCT is less toxic than allo-SCT, and appears equally potent particularly when a negative *PML-RARA* status is achieved before transplantation.
