Prognostic Significance and Treatment Implications of Minimal Residual Disease Studies in Philadelphia-Negative Adult Acute Lymphoblastic Leukemia

Abstract

Acute lymphoblastic leukemia (ALL) is curable in about 40–50% of adult patients, however this is subject to ample variations owing to several host- and disease-related prognostic characteristics. Currently, the study of minimal residual disease (MRD) following induction and early consolidation therapy stands out as the most sensitive individual prognostic marker to define the risk of relapse following the achievement of remission, and ultimately that of treatment failure or success. Because substantial therapeutic advancement is now being achieved using intensified pediatric-type regimens, MRD analysis is especially useful to orientate stem cell transplantation choices. These strategic innovations are progressively leading to greater than 50% cure rates.

Immunophenotypic aberrancies in acute lymphoblastic leukemia from 282 Iraqi patients

“…Immunophenotyping by multiparameter flow cytometry is the standard for classifying leukemias and is essential for monitoring therapy by the detection of MRD . The main characteristics and immunological subclasses of the patients enrolled in the current study are similar to most previous studies from the region and worldwide.…”

“…However, FC has the advantage of rapid turnover time of the results, the ability to distinguish viable from apoptotic cells, and being relatively less expensive in comparison with PCR. The growing standardization of FC and above all its broad applicability make it particularly useful for the assessment of MRD since nearly all ALL are evaluated for LAIP at the time of diagnosis . Among the limitations of FC are leukemic phenotypic switches and the frequent lack of standardization of the procedure with its variable sensitivity.…”

Is There a Role for Minimal Residual Disease Monitoring in Follicular Lymphoma in the Chemo-Immunotherapy Era?

“…Although not yet integrated in clinical practice as compared to other setting such acute lymphoblastic leukemia,55 MRD evaluation is commonly integrated in clinical trials testing the efficacy of new treatment protocols in FL patients. In this setting MRD maintains its consistent and independent prognostic significance.…”

Current Strategies for the Detection of Minimal Residual Disease in Childhood Acute Lymphoblastic Leukemia

“…It has the advantages of rapid turnaround time of results, which is especially important at the beginning of treatment; and broad applicability, since most ALL present identifiable leukemia-associated immunophenotypes (LAIP) at diagnosis. 4 , 14 , 16 , 20 , 33 , 42 , 47 The main limitation of the method is associated with the phenotypic similarities between leukemic lymphoblasts and nonmalignant B-lymphocyte precursors, at the stages of bone marrow regeneration during and after chemotherapy, when false-positive results are more common. It is worth highlighting the possibility of phenotypic changes in residual leukemic cells throughout treatment, compared to the antigen expression pattern at diagnosis.…”

“…On the other hand, those classified as true low risk, with undetectable MRD during chemotherapy induction/consolidation, may be spared from HSCT and its associated risks. 33 , 34 …”