Two prognostic tools help identify high-risk pediatric leukemia patients
Using 171 pediatric patients with acute lymphocytic leukemia (ALL), researchers were able to show that the minimal residual disease (MRD) indicator and the absolute lymphocyte count (ALC) together allowed physicians to better predict which patients would remain disease free and which would relapse. By using ALC along with MRD, researchers were able to identify patients who were at higher risk for relapse but were originally overlooked based on using MRD independently to predict prognosis.
The study found that after a month of treatment, patients who were MRD positive with a low ALC had an event-free survival rate of 33% and an overall 5-year survival outcome of 41%. Contrastingly, those who were MRD positive but had a high ALC had an event-free survival rate of 69% and overall 5-year survival of 92%.
Additionally reported was that most positive outcomes came from patients who were MRD negative and had high ALC, with these patients having a 99% overall 5-year survival.
“MRD is an important tool for predicting prognosis,” said Patrick Zwidler-McKay, MD, PhD, assistant professor at the Children's Cancer Hospital and first author on the study. However, he went on to say that this tool “misses a subgroup of patients who, despite having low MRD, still are at high risk of relapse. Using the ALC information, we can define which patients fall into this category. Down the line, we hope this information will allow us to alter treatment to help prevent these patients from relapsing.”
The results of this study were reported at the 2010 Annual American Society of Pediatric Hematology Oncology meeting.