Improved therapy for breast cancer patients could be on horizon

By Mark Waghorn via SWNS

Improved personalized therapy for overweight breast cancer patients could be on the horizon, according to new research.

Scientists have discovered why they sometimes don't respond to treatment - offering hope of better outcomes.

Tumours are surrounded by 'crown-like structures' that hinder response to drugs. The findings relate to a specific form known as HER2 positive.

Lead author Professor Stephen Beers, of the University of Southampton, said: "They will be of interest to clinicians and researchers involved in breast cancer treatment.

"They could potentially be used to develop personalized treatment in patients with HER2 positive over-expressed breast cancer."

They account for around one in five disease cases, which strikes 55,200 each year in the UK and 268,600 American women.

The tumours tend to be more aggressive than other types. An abnormality in the HER2 gene causes cells to grow and multiply at a rapid rate.

Survival rates are considered good - almost 100 percent of patients diagnosed with breast cancer early are expected to live at least five years.

This drops to just 22 percent in those at the metastatic stage, which isn't considered curable. Treatment is used to extend life, but may stop working.

Explained Prof Beers: "For example, doctors would know patients with a high BMI and the marker on their crown-like structures are likely to have a poor response to trastuzumab therapy.

"They may therefore benefit from more intensive anti-HER2 therapy earlier in their treatment.

"On the other hand, this study highlights how effective trastuzumab treatment is in patients that do not have the marker.

"So these patients could benefit from a lower dose of anti-HER2 therapy which may minimise the side-effects they experience."

Body fat, or adipose tissue, is an important component of healthy breasts. But high BMI (body mass index) is linked to an increased risk of developing breast cancer.

In such patients, the increased fat can cause immune cells, called macrophages, to gather in the breast's tissue.

They can then form the 'crown-like structures' - creating an inflammatory environment which can lead to the onset and growth of tumours.

How they go on to affect breast cancer progression and respond to therapy is largely unknown. Overweight patients also have worse survival rates than slimmer peers.

Prof Beers and colleagues assessed samples from HER2 positive breast cancer patients to investigate the link between high BMI and these potential 'markers'.

They also looked at the subsequent effect on how patients responded to the most effective chemotherapy drug trastuzumab, sold under the brand name Herceptin.

The results in the journal Scientific Reports showed overweight or obese patients had significantly more crown-like structures in their fat tissue surrounding the tumour.

This was associated with a faster time to metastasis where the disease has spread - an indication of how well they have responded to therapy.

The study also identified a potential molecular biomarker, called CD32B, on the surface of the macrophages.

When it was present in overweight and obese patients, their response to trastuzumab was poorer.

The researchers are now looking at ways to change the behaviour of the crown-like structures to improve responses to breast cancer therapy.

Prof Beers added: "Further studies with more patients will be needed to help confirm these initial findings."

Breast cancer kills almost 700,000 women across the globe every year.