RESPONSE to therapy in diffuse large B cell lymphoma patients can be assessed quickly by measuring changes in circulating tumour DNA (ctDNA) levels, according to a study from Stanford University, California, USA. The findings suggest that a simple blood test can predict whether a patient is likely to respond positively to their initial therapy or if they require more aggressive treatment early on, enabling a more personalised approach to care.
Predict Within 21 Days
“Although conventional therapy can cure the majority of patients with even advanced B cell lymphomas, some don’t respond to initial treatment,” commented Dr Ash Alizadeh, Stanford University. “But we don’t know which ones until several months have passed. Now we can predict non-responders within 21 days after the initiation of treatment by tracking the levels of ctDNA in a patient’s blood. We can look earlier and make a reliable prediction about outcome.”
The method could also prevent unnecessary cycles of treatment being given to those who are responding particularly well to therapy; currently, most patients with diffuse B cell lymphoma in the USA receive six cycles, but it is known that a large proportion could be cured with fewer.
In the study, ctDNA levels before initiation of treatment were compared with levels that were taken after the first and second rounds of conventional chemotherapy in 217 patients with the malignancy. The researchers then observed the correlation between the changes in ctDNA levels and patient outcomes. They found that those whose ctDNA levels had reduced 100-fold by the first round of treatment or 300-fold by the second round had a far greater likelihood of living 24 months or more without their disease recurring than those whose ctDNA levels declined more gradually.
The team are now planning a clinical trial to test the method further and discover whether it could be extended to other forms of cancer. “These findings confirm the value of tracking cancer genetics in the blood in real time,” said Dr Alizadeh. “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 cancer.”
The study followed earlier research showing that tracking ctDNA levels was an accurate predictor of lung cancer recurrence before the manifestation of clinical symptoms.
James Coker, Reporter
For the source and further information about the study, click here.