Source: Stanford University Medical Center
Summary: According to a multicenter study, a blood test can predict which patients with a type of cancer called diffuse large B cell lymphoma are likely to respond positively to initial therapy and which are likely to need more aggressive treatment.
Diffuse large B–cell lymphoma, a blood cancer, is the most common type of non-Hodgkin lymphoma. Because it is highly biologically variable, patients vary widely in their response to treatment. Although most people are cured by conventional therapy, about one-third are not. Being able to predict early in the course of treatment those who will need additional or more aggressive therapies would be a significant boon to both clinicians and patients. Circulating tumor DNA is released into the blood by dying cancer cells. Learning to pick out and read these DNA sequences among the thousands or even millions of other noncancerous sequences in the blood can provide valuable insight into the course of the disease and the effectiveness of therapy. According to a multicenter study led by researchers at the Stanford University School of Medicine, A blood test can predict which patients with a type of cancer called diffuse large B cell lymphoma are likely to respond positively to initial therapy and which are likely to need more aggressive treatment. The study findings were published in the Journal of Clinical Oncology.
In this study, the researchers tracked ctDNA levels in 217 people with diffuse large B cell lymphoma who were treated at six medical centers – three in the United States and three in Europe. For each patient, they compared levels of ctDNA before treatment began with the levels after the first and second rounds of conventional chemotherapy. They then correlated those changes with each patient’s outcome. They found that ctDNA was detectable prior to the initiation of therapy in 98% of the people studied. And, as would be expected, the amount of ctDNA in the blood dropped in all patients once treatment began. But the precipitousness of the decline varied. Those people whose ctDNA levels dropped a hundredfold after the first round or three-hundredfold by the second round were much more likely to live 24 months or more without experiencing a recurrence of their disease than those whose ctDNA levels declined more slowly.
Assoc. Prof. Ash Alizadeh, “These findings confirm the value of tracking cancer genetics in the blood in real time” and further added, “We are thinking about how to use the tools to best benefit patients, and are very excited to test this approach in other types of cancers.”
More Information: David M. Kurtz et al, “Circulating tumor DNA measurements as early outcome predictors in diffuse large B-Cell lymphoma”, Journal of Clinical Oncology (2018). DOI: https://doi.org/10.1200/JCO.2018.78.5246