Using a real-world population, researchers developed a scoring system that can categorize patients with acute promyelocytic leukemia (APL) by early-death risk. The score, which researchers said is an improvement over other scores that could be used to assess the potential of early death in these patients, could help clinicians more precisely know when to act urgently to treat patients.
“This is the first APL score predicting early death that is based on a truly population-based cohort, and it is also the first to be validated in a completely independent setting,” said Soren Lehmann, MD, PhD, professor of hematology at Uppsala University and Karolinska Institute in Sweden.
Current treatments have cure rates at about 90%, and the most serious obstacle for patients is early death from a coagulopathy that results in hemorrhage and thrombosis. Early death within a month of diagnosis has been reported in up to 30% of cases.
Researchers used data from all 301 adult patients who were diagnosed with APL in Sweden between January 1997 and December 2020. They validated the model with all patients who were diagnosed with APL and treated at the University Hospital Center of São João in Portugal from January 2005 to April 2019.
Researchers looked at a range of variables and assessed each one for its relation to the risk of early death to determine cut-offs that could be clinically useful in a risk score. Age, white blood cell count, and platelet count were found to be the most significant variables.
In the training cohort, early death was seen in 4.8% of those with scores in the low-risk group, 20.2% of those with high-risk scores, and 50.9% of those with very high-risk scores. In the validation cohort, early death was seen in 6.7% of the low-risk group, 25% of the high-risk group, and 36% of the very high-risk group.
In their analysis of the variables’ effects on risk, researchers found that white blood cell counts were associated with early death risk even at levels below normal and then rapidly increased in the normal range and beyond. Taking lower counts into consideration, as this new risk score model does, is vital, Dr. Lehmann said.
“We envision that the score can help clinicians identify patients with a high or very high risk of early death, and that such patients should be subjected to an intensified monitoring and more aggressive preventive measures,” Dr. Lehmann said.
The score was designed to be easy to use, with cut-offs that are clinically reasonable. Researchers included a graphical tool to assess patients’ scores in their publication in Haematologica, along with a website that can be used for the calculation.
The “crucial question,” according to Dr. Lehmann, is what to do for patients assessed as having a high risk of early death. He advised that they should have their platelets and fibrinogen monitored as often as four to six times a day with a policy of rapid transfusions when the need arises.
Ideally, there would be scientific evidence behind preventive measures, but, Dr. Lehmann added, “in a situation without this evidence, we need to discuss and suggest measures that could help prevent especially hemorrhagic events in the high-risk patient. Thus, what type of additional measures that should be taken is a matter of continuous discussions, considerations, and studies.”
Any conflicts of interest declared by the authors can be found in the original article.
Reference
Österroos A, Maia T, Eriksson A, et al. A risk score based on real-world data to predict early death in acute promyelocytic leukemia. Haematologica. 2022;107(7):1528-1537.