Biomedical Engineering Reference
In-Depth Information
The age limit (>60 years) remains, but older patients are increasingly considered for
a transplant and RIC protocols. Transplant procedures consist of several steps, first
reducing the tumor burden by conditioning regimen (3-4log), immunosupression as
the prevention of GvHD, as well as prevention therapy of infections due to neutro-
penia. The HLA barrier remains the most important factor, so the best results are
those using an HLA-compatible family donor. HLA-compatible sibling transplant is
standard reference for any other transplant. The results for AML patients trans-
planted in CR1 (first complete remission) give a probability of LFS from 45 to 70%
[
52
].The relapse rate is approximately 20-25%. Additionally, MUD transplant rep-
resents the major effort of transplant centers in last decade. Now, there are more
than ten million potential donors. The continuous improvement of HLA typing is
associated with improved results. Current strategies in the treatment of AML
patients suggest that for poor-risk patient, allogeneic SC transplant in CR1 is the
only best solution. For intermediate-risk patients, who represent the majority of
AML patients allogeneic SC transplant probably represents the best option if an
HLA-matched sibling donor is available. Chemotherapy is not inferior to transplant
in good-risk patients. Acute promyelocytic anemia is never recommended for trans-
plant if the PCR for PML-RARa is negative, and chemotherapy is an optimal treat-
ment option.
Acute lymphoblastic leukemia (ALL)
. Hematopoietic SC transplant has important
role in the treatment for ALL patients. However, indications for SC transplant in
first CR scheduling and procedures are still not completed yet. Most European
ALL study groups define an indication for SC transplant in patients with unfavor-
able prognosis with survival probability less than 40% with chemotherapy alone
[
53
]. Due to the poor outcome with intensive chemotherapy, SC transplant has
always been the therapy of choice for Ph
+
ALL. Nowadays the majority of these
patients receive imatinib as front-line therapy, without an increase in TRM if SC
transplant is performed thereafter. The survival after allogeneic SC transplant in
first CR is 27-65% [
54
]. The presence of detectable minimal residual disease
(MRD) beyond first consolidation chemotherapy provides an important new indi-
cation for SC transplant. There is a general agreement that all patients in second or
later CR are candidates for SC transplant. This includes molecular relapse, which
represents the reappearance of MRD above 10
−4
to 10
−3
. Recommendations of
Germal Multicenter study Group for Adult ALL (GMALL) are given according to
risk adapted approach. For high-risk patients allogeneic SC transplant (sibling or
MUD) is recommended. In standard-risk patients, priority is allogeneic SC trans-
plant in molecular nonresponders. Therefore, in patients with second CR, alloge-
neic SC transplant is necessary.
Myelodisplasia (MDS).
MDS consists of a heterogenous group of clonal stem cell
disorders. The spectrum of MDS varies from a disease with an indolent course over
several years to a form with rapid progression to AML. Disease is characterized by
deficiency of hemopoiesis associated with severe cytopenias, leading frequently to
acute leukemia. The majority of MDS patients are older than 60 years. For this
