Analysis of the entire tumour RNA picks up more clinically relevant genetic changes in children with cancer than traditional diagnostic methods, new research has shown.
FREMONT, CA: All children with cancer have a sample of tumour tissue removed to identify the type of cancer they have. The tissue is examined under a microscope, but it is also tested for genetic flaws. Changes in DNA and RNA, which is a translation of the DNA code, can reveal vital information about the cancer type, tumour aggressiveness, and the potential benefit of targeted treatments.
In addition to standard diagnostics, every available RNA in the tumour tissue with cancer in the Netherlands is analysed using so-called "RNA sequencing." The Princess Máxima Center for Pediatric Oncology, a research facility where all children with cancer in the Netherlands are treated, made this possible in 2018. RNA sequencing has already resulted in improved diagnosis and therapy for some patients. The Diagnostic Lab at the Princess Máxima Center has already replaced standard tests with wide RNA studies for a substantial number of cancer types.
The researchers believe they will be able to switch swiftly for additional cancer kinds, particularly leukaemia variants. Scientists at the Princess Máxima Center compared the effectiveness of RNA sequencing to traditional methods for searching the DNA and RNA for known gene mutations in a new study. The researchers examined tissue samples from 244 children who were referred to the Princess Máxima Center after being diagnosed with cancer between late 2018 and mid-2019. They concentrated on detecting so-called fusion genes, which are a type of genetic flaw in which two different genes combine to form a single defective gene. Many tumors have fusion genes, which can influence therapy decisions. The researchers discovered a total of 78 fusion genes using RNA sequencing. This was 23 percent more than they discovered using usual methods. The remaining 55 fusion genes were discovered using traditional methods, but in many cases, only one of the two genes from the fusion was detected, despite the fact that information from both genes is critical for diagnosis and therapy.