How Often Does Early Breast Cancer Metastasise?

Date: Jun-18-2012Women diagnosed with early breast cancer can now be offered important information about prognosis
according to the authors of research published in the June 18 issue of the Medical Journal of Australia.

One in ten Australian women diagnosed with non-metastatic breast cancer will go on to develop the
metastatic form of the disease within 5 years - but if the cancer has spread to nearby lymph nodes or
adjacent tissue, the risk rises to 1 in 6, according to Dr Sarah Lord from the NHMRC Clinical Trials Centre
at the University of Sydney and coauthors.

The researchers studied 6644 NSW women diagnosed with non-metastatic breast cancer in 2001 and 2002
to determine how many went on to develop the metastatic form of the disease.
They classified women with non-metastatic breast cancer into two groups: localised (those with nodenegative
tumour confined to breast tissue) and regional (those with spread to regional lymph nodes or
adjacent tissues).

The overall risk of metastatic disease for both groups was 10%, but for those with localised cancer, the
news was much better: only 1 in 20 went on to develop metastatic breast cancer (MBC) within 5 years.

The authors said their findings showed that, in addition to underlying tumour biology, the spread of disease
at diagnosis remained an important prognostic factor.
"Clinicians can use these estimates to inform women with breast cancer about the average risks of
developing MBC", they wrote.

Those found to be most at risk of MBC were women aged less than 50 years and those living in areas of
lower socio-economic status. Also, the chance of being diagnosed with metastatic breast cancer was
highest in the second year after initial breast cancer diagnosis.

"This information may provide some reassurance for women who completed their primary breast cancer
treatment more than 2 years ago and remain recurrence free", the authors wrote.

Although the risk of developing MBC is one of the major concerns for women with a diagnosis of early
breast cancer, very few population-based studies have examined MBC incidence in those with nonmetastatic
breast cancer at initial diagnosis, the authors wrote.

In the same issue of the journal, MJA editor Dr Annette Katelaris wrote that the research provided "real
world" data that would inform discussions between clinicians and women newly diagnosed with breast
cancer.

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.