A cancer diagnosis and the subsequent treatment is a scary, stressful, and physically taxing experience in anyone’s life—and especially for children. However, doctors at Cambridge University in England have been able to use whole-genome sequencing to make this process smoother for children with cancer.
What is whole-genome sequencing?
Whole-genome sequencing means reading the full genetic code of a cancer. This is a method that, according to the pilot study, allows doctors to improve diagnoses, deepen their understanding of how tumors will progress, and help pinpoint the most effective therapies.
The doctors applied whole-genome sequencing on 36 children with cancer and determined that this method provided them with extra information which resulted in the altering of four patients’ original diagnoses, as well as leading to new treatment options for seven other cases.
Through a full reading of the cancer’s DNA, doctors improved two previous diagnoses, were more able to accurately predict the course of disease in eight patients, and found potential hereditary reasons for two of the tumors.
“Our aim was to illustrate what can be achieved with whole-genome sequencing and try to advertise its utility,” said Dr. Patrick Tarpey, lead scientist for solid cancer in the east Genomic Laboratory Hub based at Cambridge University hospitals NHS foundation trust.
The whole-genome sequencing approach was first introduced in the 100k genomes project, an initiative by the UK government and managed by Genomics England that successfully sequence 100,000 genomes from approximately 85,000 NHS patients with rare diseases or cancer. NHS England hopes to soon make the whole-genome sequencing test part of routine care.
The test requires doctors to compare the complete genetic makeup of a tumor with the DNA of healthy tissue from the same patient. This allows them to take note of the mutations that are driving a cancer, and possibly unveil gene variants that make the tumor vulnerable to certain drugs or treatment. The interpretation of the test results itself takes two or three months, but in spite of its long processing time, it has proven to be valuable in flagging gene variants and refining diagnoses.
“There are cases where the diagnosis was completely uncertain and we’ve been able to confirm it, and in doing so identify the mechanisms that impaired the genes,” Tarpey explained.
This is especially important in identifying the correct or most effective treatment for children so that they don’t have to undergo trial and error treatments and can simply start with the best one for their cancer.
“It is vital that we find ways to tailor treatments toward the individual and for this, whole-genome sequencing is a game-changer,” said Sheona Scales, pediatric lead at Cancer Research UK. “Understanding more about the makeup of a child’s cancer can help doctors make the most informed treatment choices for their parents.”
The doctors behind this pilot study hope that their work will lead not only to better survival rates for children with cancer but a better standard of life during their treatment and post-recovery.