Role of Mid-induction Peripheral Blood Minimal Residual Disease Detection in Pediatric B-Lineage Acute Lymphoblastic Leukemia.

OBJECTIVE

To study the role of mid-induction (day 15) peripheral blood minimal residual disease (PB-MRD) detection in pediatric B- lineage acute lymphoblastic leukemia (B-ALL).

DESIGN

Prospective.

SETTING

Tertiary-care center.

PATIENTS

40 consecutively-diagnosed treatment-naive, pediatric B-ALL patients.

INTERVENTION

National Cancer Institute (NCI) standard risk patients were given three drug induction regimen comprising vincristine, L-asparginase and prednisolone; NCI high-risk patients were supplemented with daunorubicin.

MAIN OUTCOME MEASURE

Day 15 PB-MRD and bone marrow MRD (BM-MRD) analyzed by six color flow cytometry.

RESULTS

The sensitivity of day 15 PB-MRD to identify concurrent day 15 BM-MRD positivity was 64%, with 100% specificity. The positive and negative predictive values were 100% and 62.5%, respectively. PB-MRD was positive in 67% of relapsed patients.

CONCLUSION

BM-MRD is a well-established prognostic factor in B-ALL. We suggest, day 15 PB-MRD could be considered as an early, minimally invasive and easily accessible MRD screening option.