Breast cancer 'is 10 different diseases'

“Breast cancer is effectively ten different diseases,” the Daily Mail has today reported. The newspaper says that a “landmark” study has reclassified the country’s most common cancer in “breakthrough research” that could revolutionise the way we treat breast tumours.

During the study, researchers analysed the genetic features of 2,000 frozen samples of breast cancer tumours, taken from women diagnosed with the disease over the past 10 years. From this analysis, scientists found breast cancer could be classified into 10 different broad types according to their common genetic features. These subgroups were associated with different outcomes for patients.

The large study has shown that breast cancer tumours can be classified into 10 new subtypes with varying outlooks. This research is a valuable contribution to scientists’ understanding of the genetic basis of breast cancer and it may also help to explain why, at present, some tumours appear to respond well to treatment while others do not. It is possible that, in the future, doctors may be able to use this information to predict the outlook for individual breast cancer patients better and to tailor treatments accordingly. However, it’s important to note that this study will not affect the way women are currently treated for breast cancer. As the scientists acknowledge, before these findings can affect clinical practice, further work is needed to understand how tumours classified under each subgroup behave, and also which treatments they may respond to.

Professor Carlos Caldas from Cancer Research UK said: “Essentially, we've moved from knowing what a breast tumour looks like under a microscope to pinpointing its molecular anatomy – and eventually we'll know which drugs it will respond to”.

Today’s news is based on a laboratory study that analysed the genetic makeup and genetic activity in more than 2,000 breast cancer tumours. Understanding the genetic makeup of tumours is important as their genetics can potentially influence whether they are resistant or susceptible to particular drugs, and also their behaviour within the body. The aim of the study was to find out if the genetic characteristics of the tumours could be classified and matched according to clinical outcomes.