Scientists from the Sanger Institute in Cambridge, UK and their international collaborators have just published a paper in Cancer Cell entitled “Genomic evolution of breast cancer metastasis and relapse” that has important clinical implications. Their introduction set the stage: “Metastatic breast cancer is almost universally fatal within 5 to 10 years, a dismal statistic that has not changed in the past 20 to 30 years.” The recurrence of the cancer can take two forms: either a distant metastasis – in the lung, brain, liver or bones – or regionally in the breast and nearby lymph nodes. The researchers set about understanding the biology underpinning breast cancer and the timing of its spread to other parts of the body.

The team sequenced the DNA of 299 tumours from 170 patients with breast cancer that had either relapsed in the original site, or metastases that had spread to distant sites. There had been some uncertainty whether the cancer cells that spread to other parts of the body break away from the primary tumour in the breast at an early or late stage in development of the cancer. The researchers showed that genetic changes in the original tumour were also present in the metastatic tumours, demonstrating the late spread of cancer cells as the disease developed.

Lead author Lucy Yates commented: “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.” Co-author Per Eystein Lønning explained: “Most women who have metastatic breast cancer do not have another biopsy of the cancer, and rarely have it analysed using genetic sequencing. 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.”

The research has now led to a European clinical trial with the recruitment of a large cohort of patients with metastatic breast cancer where the aim is to test new treatments that are personalised for each patient (image at left: © Sanger Institute). Corresponding author Peter Campbell cut to the chase: “Our study shows that in order to catch breast cancer before it spreads, early detection is key, and we provide a good rationale for continuing to improve methods for detecting breast cancer sooner.”

Despite the naysayers who warn against the harms of screening, at CapeRay we believe in good science and are dedicated to the development of tools for the early detection of breast cancer.