Somatic Mutations Increase in Post-Treatment Blood Samples from Pediatric Cancer Patients

Chemotherapy appears to boost the prevalence of somatic mutations in peripheral blood cell samples from former pediatric cancer patients, according to research slated to appear in the Proceedings of the National Academy of Sciences this week. Using a low-coverage sequencing method known as "enzymatically cleaved and optimal sequencing," or EcoSeq, researchers from Japan's National Cancer Center Research Institute and the University of Tsukuba characterized somatic mutations in blood samples collected from pediatric sarcoma patients before and after chemotherapy treatment, documenting a significant rise in somatic mutation frequencies that persisted for up to years. "Chemotherapy was shown to have significantly induced somatic mutations in normal peripheral blood cells, likely reflecting those in hematopoietic stem cells in bone marrow," they report, noting that "chemotherapy enriched the mutational signature associated with prior platinum-based chemotherapy."