A promising report from The Guardian:
Early signs of cancer can appear years or even decades before diagnosis, according to the most comprehensive investigation to date of the genetic mutations that cause healthy cells to turn malignant.
The findings, based on samples from more than 2,500 tumours and 38 cancer types, reveal a longer-than-expected window of opportunity in which patients could potentially be tested and treated at the earliest stages of the disease.
The work was carried out as part of the Pan-Cancer Analysis of Whole Genomes project, the most comprehensive study of cancer genetics to date.
“What’s extraordinary is how some of the genetic changes appear to have occurred many years before diagnosis, long before any other signs that a cancer may develop, and perhaps even in apparently normal tissue,” said Clemency Jolly, a co-author of the research based at the Francis Crick Institute in London.
“Unlocking these patterns means it should now be possible to develop new diagnostic tests that pick up signs of cancer much earlier,” said Peter Van Loo, co-lead author, also of the Crick Institute. “There is a window of opportunity.”
The discovery that the seeds of cancer are often sown many years before the first symptoms arise will not change cancer screening in the immediate term. But it points to the possibility that those at risk could be spotted far earlier.
The study revealed that about half of the earliest mutations occurred in just nine genes, meaning there is a relatively small pool of common genes that serve as triggers for cells to diverge from healthy development to a path towards cancer. It might be possible, in future, to pick up such mutations using so-called liquid biopsies – genetic tests that detect mutations in free-floating DNA carried in the blood that can indicate the presence of tumours elsewhere in the body.
—“Signs of cancer can appear long before diagnosis, study shows”
While I learned long ago to be skeptical of reports of medical studies in newspapers, this seems like a massive breakthrough. The earlier the cancer is detected, obviously, the earlier it can be treated.
