Thursday 06 August 2009
Research by scientists at the Breakthrough Breast Cancer Research Centre at The Institute of Cancer Research (ICR) has revealed a new sensitive method that may help identify additional women who could benefit from the drug trastuzumab (Herceptin).
Results published in the Journal of Pathology suggest that the way in which HER2 positive breast cancers are currently identified may miss a small number of patients that could benefit from targeted therapies against HER2. HER2 positive breast cancer makes up about one in five of the nearly 46,000 cases of the disease diagnosed in the UK each year. Herceptin is a targeted therapy for this type of breast cancer.
The research was led by Dr Jorge Reis-Filho at the Breakthrough Breast Cancer Research Centre at The Institute of Cancer Research (ICR) in London. He used DNA microarrays, a very precise way to examine the number of copies of the HER2 gene in a tumour.
Using this more accurate test, Dr Reis-Filho’s team discovered that two of the 12 patients’ HER2 gene signals studied would have been underestimated using current clinical tests. This means that these patients may not have been prescribed Herceptin when they could have benefited from it.
The current gold standard test for HER2 status of women with breast cancer is a technique called FISH (fluorescent in situ hybridisation) in which the number of copies of the HER2 gene is compared with a marker for chromosome 17. This determines whether there is an increased number of HER2 gene signals compared with the number of copies of chromosome 17.
This study suggests that, while this test works well for the majority of cases, there are some instances where FISH is not accurate. In these cases, using DNA microarrays would provide a more accurate way to determine HER2 positive tumours. At present, this cannot be done in the clinic but the study’s authors suggest a way that will provide greater accuracy for a woman’s diagnosis.
Dr Jorge Reis-Filho said: “Finding more accurate ways to classify tumours at the molecular level is essential for targeted treatments to fulfil their potential in the clinic.
“Our research shows that for some patients a different test for HER2 may be necessary to make sure they are offered an appropriate range of treatment options. However, larger clinical studies are needed to fully evaluate our findings.”
Media contact: Richard Purnell in the Breakthrough Breast Cancer press office on 020 7025 0290 or [email protected].
Notes to editor:
The Research Article
The research paper in the Journal of Pathology is entitled, ‘Does chromosome 17 centromere copy number predict polysomy in breast cancer? A fluorescence in situ hybridisation and microarray-based CGH analysis.’
The article may be accessed online, free of charge at: http://dx.doi.org/10.1002/path.2574
A supporting commentary can also be accessed online, free of charge at: http://dx.doi.org/10.1002/path.2593
The Journal of Pathology
As the journal of the Pathological Society, The Journal of Pathology aims to serve as a bridge between basic biomedical science and clinical medicine with particular emphasis on morphologically based studies. The Journal of Pathology can be accessed online at: www.thejournalofpathology.com.
- Breast cancer is the most commonly diagnosed cancer in the UK – nearly 46,000 women and around 300 men are diagnosed every year.
- 15-20% of all breast cancers are HER2 positive. These tumours have a more aggressive clinical behaviour and can be treated with agents targeting HER2.
- Breast cancer accounts for nearly 1 in 3 of all female cancers and one in nine women in the UK will develop breast cancer at some point in their lifetime.
- The good news is that more women than ever in the UK are surviving breast cancer thanks to better awareness, better treatments and better screening.
The Institute of Cancer Research
The Institute of Cancer Research is Europe’s leading cancer research centre with expert scientists working on cutting-edge research. In 2009, the ICR marks its 100 years of groundbreaking research into cancer prevention, diagnosis and treatment. The ICR is home to the world’s leading academic drug development team, which has developed many drugs now used as standard cancer treatments. It continues to be at the forefront of drug development, discovering an average of two preclinical candidates each year over the past five years. In December 2008, the ICR was ranked as the UK’s leading academic research centre by the Times Higher Education’s Table of Excellence, based on the results of the Higher Education Funding Council’s Research Assessment Exercise. The ICR is a charity that relies on voluntary income. It is one of the world’s most cost-effective major cancer research organisations with more than 95p in every £ directly supporting research. For more information visit www.icr.ac.uk.
Breakthrough Breast Cancer
Breakthrough Breast Cancer is the UK’s leading charity committed to fighting breast cancer through research, campaigning and education. In 1999 Breakthrough established the UK’s first dedicated breast cancer research centre. The Breakthrough Toby Robins Breast Cancer Research Centre is housed in the Mary-Jean Mitchell Green building at The Institute of Cancer Research in association with the Royal Marsden Hospital.
Under the directorship of Professor Alan Ashworth FRS, the Breakthrough Research Centre now has 120 world-class scientists and clinicians tackling breast cancer from all angles – from understanding the normal growth and development of the breast, how breast cancer arises and how the cancer spreads, to treatment and ultimately disease prevention. Scientists at the Breakthrough Research Centre have a range of expertise and approaches and together they are working towards a common goal: a future free from the fear of breast cancer.
Breakthrough Breast Cancer campaigned for Herceptin to be made available on the NHS to all breast cancer patients who may benefit from it.
For further information about Breakthrough or breast cancer please visit www.breakthrough.org.uk or call the charity’s free information line on 08080 100 200.