Study finds 'wandering' cells in early-stage breast cancer
Researchers have found that some early-stage breast tumours may already contain cells that are able to move around, even though the tumours have not yet spread to the surrounding tissues.
The discovery puts paid to the idea that early-stage tumours have not yet gained the ability to move and could allow doctors to tailor treatment better.
Most breast tumours are in their early stages when discovered through screening programmes and are confined to a duct in the breast, hence their name 'ductal carcinoma in situ' (DCIS).
Treatment usually involves a lumpectomy to remove the tissue and its surrounding tissue. Occasionally radiation can be used as well, but the decision over whether or not to also use radiation therapy tends to be based on the size of the tumour.
However, the latest findings could mean that radiation therapy may be recommended for more patients, based on whether their tumours contain mobile cancer cells, as the tumour cells, while not yet able to spread to the lymph nodes, may have the potential to migrate along milk ducts and form new tumours within the breast.
Lead author Dr Gray Pearson, a postdoctoral researcher at the Salk Institute for Biological Studies, explained: "A lack of invasion suggested a lack of motility, but that's not so.
"Our findings suggest that, if a DCIS contains these highly motile cells, the patient may have an increased risk for recurrent growth.
"Under these circumstances you would consider adding radiation treatment regardless of tumour size."
However, the researchers - whose findings are published in the Journal of Cell Biology - note that there is no evidence at this stage that wandering cells influence a patient's outcome.
The cells, while motile, seem to be unable to invade the surrounding tissue, although Dr Pearson noted: "The acquisition of motility prior to invasion presumably lowers the barrier for future invasive growth."
Commenting on the research, senior author Dr Tony Hunter, a professor in the university's Molecular and Cell Biology Laboratory, said: "This is an exciting finding because it suggests that cells might acquire migratory properties much earlier than expected."