False-Positive and False-Negative MRD Results in Children with Acute Lymphoblastic Leukemia: Navigating Between Scylla and Charybdis (Brief Review and Clinical Experience).

BACKGROUND/

OBJECTIVES

Acute lymphoblastic leukemia (ALL) is the most common malignant disease in children. Contemporary antitumor treatment protocols provide long-term survival rates in over 90% of patients with ALL. High effectiveness of the treatment has been achieved as a result of chemotherapy optimization, use of targeted drugs, up-to-date genetic information, and detection of minimal residual disease (MRD). Current highly sensitive methods for MRD detection have advantages and disadvantages, and the challenge is to distinguish between false-positive and false-negative tests.

METHODS

A comprehensive search through MEDLINE, PubMed, Scopus, and ScienceDirect using the MRD-related keywords was performed, and included a final set of 72 academic articles.

RESULTS

At present, flow cytometry for MRD detection provides the necessary sensitivity of 10-4 and allows for reliable prediction of ALL dynamics and effective therapeutic strategies. However, even multicolor flow cytometry (MFC) cannot avoid cases of false-positive or false-negative results. Highly sensitive and productive genomic methods in addition to MFC may enhance the accuracy of MRD evaluation. On the other hand, overwhelming efforts to reach the highest sensitivity of the detection methods may lead to the detection of clinically insignificant manifestations of minimal residual disease and, subsequently, to unjustified escalation of antitumor therapy.

CONCLUSIONS

The necessary ground for an adequate sensitivity of the MRD detection methods could ensure the fine line between false-positive and false-negative MRD results in patients with childhood ALL to develop an appropriate therapeutic strategy.