Metastatic breast cancer cells break away from the primary tumour at a late stage, according to a genetic study unveiled last night.
The finding, from the Wellcome Trust Sanger Institute, Cambridge, is one of the first to emerge from genome sequencing of different cancer stages.
The researchers say the metastasis is the result of genetic changes in the primary tumour – rather than from cells breaking away at an early stage of disease.
Publishing in Cancer Cell, they report that metastatic cells had the same genetic changes as found in the original breast tumour – suggesting that they broke away after changes took place.
The researchers say this shows benefit in developing treatments to target genetic changes in the primary tumour and prevent metastasis.
The findings come from an analysis of 299 tumours from 170 patients.
Researcher Dr Lucy Yates, of the Guys and St Thomas’ NHS Trust, London, said: “As the cells that cause the spread of breast cancer leave relatively late, it means they are still quite similar to the cells in the primary tumour.
"Therefore by studying the genome of the primary breast cancer tumour, in the future we may be able to predict what cells that might have spread look like, and potentially which treatments they will respond to.”
Fellow researcher Professor Per Eystein Lønning, from the University of Bergen, Norway, said: “Most women who have metastatic breast cancer do not have another biopsy of the cancer, and rarely have it analysed using genetic sequencing.
"In this study we found that in some cases, the metastatic tumours had particular genetic changes that could be targeted with treatments. We would not have seen these mutations by sequencing the primary tumour alone.
"Our results suggest that it should be more routine to biopsy the metastasis and have it genetically analysed in order to open up clinical trials of treatment options for metastatic breast cancer.”
Lucy Yates et al. Genomic evolution of breast cancer metastasis and relapse. Cancer Cell 14 August 2017; doi: 10.1016/j.ccell.2017.07.005
Leave a Reply