In new research published today, researchers uncover evolution in action in cancer cells. They show the forces of evolution in pancreatic tumours mean that not only is cancer genetically different between different patients, but each new focus of cancer spread within a patient has acquired distinct mutations.
Effectively, ten different foci of cancer spread are ten different, but related, tumours. The complexity of pancreatic cancer genetics uncovered in this work helps to explain the difficulty of treating the disease but also strengthens the need for improved methods for early diagnosis
Pancreatic cancer is an aggressive malignancy with only two or three patients in one hundred living beyond five years from first diagnosis. The spread metastasis of the tumour is thought to be relatively symptomless in most patients until the disease is advanced.
"We have always known that pancreatic cancer is a particularly aggressive disease," says Dr Peter Campbell, from the Wellcome Trust Sanger Institute and first author on the paper. "This study illustrates why it is so challenging. Each metastasis is its own tumour, each evolving, each striving for dominance, each adapting to life outside the pancreas. When we treat cancer that has spread through the body, we're not just treating one tumour, we might be treating tens of genetically distinct tumours."
The researchers, from the Wellcome Trust Sanger Institute, near Cambridge, UK and the Sol Goldman Pancreatic Cancer Research Center at Johns Hopkins Medical Institutions, Baltimore, USA, looked at cancers in 13 patients who died from pancreatic cancer. They mapped rearrangements in the genomes of cancer samples: in some cases, they looked at several metastases from a patient.
They discovered that pancreatic cancer genomes often contain a distinctive pattern of genome rearrangement that possibly reflects changes to repair mechanisms in the cancer cells. The pattern of mutatio
|Contact: Don Powell|
Wellcome Trust Sanger Institute