Study discovers origin of cancer metastases and why they reoccur

A team of scientists from The Scripps Research Institute (TSRI) have discovered the secrets of where metastases originate and why certain cancers resurge even after years in remission, through the first study to investigate entire tumours in order to identify the origins of secondary cancer cell distribution.

The researchers found that tumour cells begin to be produced by the primary cancer at a much earlier point on the timeline than was previously thought, and enter the bloodstream via blood vessels within the core of the tumour, rather than from its invasive borders. This leads to the formation of secondary tumours which may not be identified for years.

TSRI Assistant Professor Elena Deryugina led the study in a long-term collaboration with TSRI Staff Scientist William Kiosses.  "The actual process of cancer cell dissemination via haematogenous routes is a relatively under-studied process, but we finally have an answer as to where it takes place," she noted.

To reach these conclusions, the team utilised cancer cell lines generated from human fibrosarcoma and carcinoma tumours, finding that it is possible for the distribution of cancer cells to occur independently of the tumour’s invasion into surrounding tissue, illuminating how it is that metastatic cases develop even in early forms of the disease. "These metastases may have been seeded when the primary tumour was even too small to be visualised," Deryugina explained.

These findings could lead to a rethink of the cancer treatment timeline, and have significant implication on patients in the future. The team now hope to supplement this research with studies into the functions of each of a tumour’s cell types.