Compared with flow cytometry, a high-speed DNA-decoding technology known as high-throughput sequencing was able to identify minimal residual disease in nearly twice as many persons with leukemia.
Flow cytometry counts the number of cells with cancer-specific protein markers on their surface. In the United States, it is considered the gold standard for detecting minimal residual disease, a major predictor of cancer relapse characterized by a small number of cancer cells that survive treatment and persist in patients.
Now, a clinical trial has found high-throughput sequencing, which can determine thousands or millions of sequences of nucleotides along strands of DNA, to be at least 20 times more sensitive than flow cytometry in detecting minimal residual disease. In addition, high-throughput sequencing is highly automated and therefore less vulnerable to operator error and less time-consuming than flow cytometry.
For the study, Harlan Robins, PhD, of the Fred Hutchinson Cancer Research Center in Seattle, Washington, and colleagues assessed minimal residual disease at posttreatment day 29 in 43 patients with acute T lymphoblastic leukemia. The investigators reported in Science Translational Medicine (2012;4:134ra63) that high-throughput sequencing picked up minimal residual disease in 22 patients, compared with 12 patients for flow cytometry.
Patients whose cancer recurrence is detected early could be treated sooner, increasing their chance for survival. Eventually, high-throughput sequencing might even allow for much earlier diagnosing of leukemia and lymphoma than is currently possible.