News Release

Scientists announce world's most sensitive cancer test

A new way of testing cells for cancer can both diagnose and determine the stage of cancer with just 50 tumour cells

Peer-Reviewed Publication

IOP Publishing

Speaking at the Institute of Physics conference Physics 2005 in Warwick today (Tuesday 12th April), scientists will reveal a new test for cancer, more sensitive than any existing technique and capable of predicting for the first time whether a tumour has spread.

Unlike existing techniques which rely on expert visual assessment or unreliable biochemical measurements, the "optical stretcher" tests the physical strength of each cell and can give a diagnosis using as few as 50 cells, allowing doctors to test for cancer where traditional biopsies are dangerous or even impossible. The ability to measure the progress of a cancer by examining only the primary tumour should reduce the number of unnecessary and traumatic mastectomies in women with breast cancer.

Professor Josef Käs and Dr Jochen Guck from the University of Leipzig have been developing the new procedure for several years and today described how the system is being tested, both to screen for oral cancers and in the "staging" of breast cancer tumours.

Professor Käs' technique for the first time uses a physical characteristic of each cell – its stretchiness or elasticity – instead of its biological make-up, to decide whether or not it's cancerous. Cancer cells tend to de-differentiate, losing the special characteristics of the organ where they started life. Because of this, they no longer need the rigid cytoskeleton which holds them in shape, making them stretchier than normal cells.

Käs and Guck's machine uses a powerful beam of infrared laser light to stretch and measure cells one by one. His optical stretcher differs from an existing tool known as optical tweezers in which the light is focused to a sharp point to grab hold of a cell. In contrast, the optical stretcher doesn't use focused light. This allows laser beams strong enough to detect stretching to be used without killing the cell.

"Of all the physical properties of a cell," explains Professor Käs, "elasticity is the one which varies most dramatically between normal and cancerous cells." This makes stretching the most sensitive method known for identifying cancer. Just 50 tumour cells are needed in a sample for the optical stretcher to diagnose cancer, contrasting with traditional methods which need 10,000 to 100,000 cells. With such small samples, diagnoses can be made even before solid tumours develop, or where a traditional biopsy is problematic.

More importantly, the optical stretcher can yield crucial information on the spread of cancer. The softer the cancer cells, the more likely they are to travel through the body and produce secondary tumours (known as metastases). Traditionally, doctors have had to check nearby lymph nodes for cancer cells. However, the optical stretcher can determine, just by measuring cells from the primary tumour, whether or not the cancer will spread. This is the first time that anyone has been able to diagnose metastasis without locating the secondary tumours.

Secondary tumours can be difficult to find, and women with breast cancer often undergo precautionary mastectomy or whole-body chemotherapy. The optical stretcher will allow many women to avoid the emotional and physical side-effects of such unnecessary treatment.

The optical stretcher can test as many as 3,600 cells per minute, so is already fast enough to be useful in clinical diagnosis of cancer. Professor Käs believes that this high speed and the equipment's low cost could even herald a shift towards cancer prevention. Dentists, for example, could swab their patients for mouth cancer cells even before a solid tumour develops. Pre-clinical trials are already underway in Germany, and Professor Käs is keen for an industrial partner to see his prototype machine through to full clinical testing.

Professor Josef Käs is Director of the Institute for Soft Matter Physics at the University of Leipzig, Germany.

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Contact: Professor Josef Käs, Institute for Soft Matter Physics, University of Leipzig, Email: jkaes@physik.uni-leipzig.de, Tel: 49-341-973-2471, Secretary: Claudia Honisch, tel. 49-341-973-2470, Mobile: 0179-9043672 Home: 49-341-124-8944

Josef Käs research webpage: http://www.softmatterphysics.com/

Professor Käs is available for interviews: Contact David Reid, Institute of Physics, 44-207-470-4815 to arrange an interview.

Notes to editors:

Delivery: This presentation will be delivered at 11:30am Tuesday 12th April 2005.

Physics 2005 takes place at the University of Warwick from 10th – 14th April 2005. It is the main academic conference for the UK physics community during Einstein Year and the largest gathering of physicists in the UK. At the meeting scientists will present exciting new research from emerging fields in physics.

For more information see: http://www.physics2005.iop.org

Contacts:

Institute of Physics Press Office
Tel: 44-207-470-4815

Physics 2005 Newsroom
Tel: 247-657-2982 or 247-657-2983
E-mail: physics2005newsroom@iop.org
The Newsroom will be staffed from Sunday 10th 2pm – 5pm and daily from 8.30am until Thursday 14th April.

Physics 2005 Newsroom Team David Reid, Mobile: 0794-632-1473, E-mail: david.reid@iop.org
Alex Seeley, Mobile: 0796-732-6646, E-mail: physics2005newsroom@iop.org

Einstein Year is a year-long celebration of physics and its relevance to all our lives. Marking the centenary of Einstein's three ground-breaking ideas it communicates the vital role physics plays in developing new technologies such as cancer screening equipment and mobile phones, whilst addressing big questions like how the Universe was created and how climate change can be addressed. Einstein Year will inspire and inform the next generation of physicists as well as those who are just curious about the world around them. Einstein Year is the UK and Ireland's contribution to International Year of Physics, a UN-sponsored project to promote physics in 2005.

Einstein Year is a year-long celebration of physics and its relevance to all our lives. Marking the centenary of Einstein's three ground-breaking ideas it communicates the vital role physics plays in developing new technologies such as cancer screening equipment and mobile phones, whilst addressing big questions like how the Universe was created and how climate change can be addressed. Einstein Year will inspire and inform the next generation of physicists as well as those who are just curious about the world around them. Einstein Year is the UK and Ireland's contribution to International Year of Physics, a UN-sponsored project to promote physics in 2005.

The Institute of Physics is a leading international professional body and learned society with over 37,000 members, which promotes the advancement and dissemination of a knowledge of and education in the science of physics, pure and applied. It has a world-wide membership and is a major international player in:

  • scientific publishing and electronic dissemination of physics;
  • setting professional standards for physicists and awarding professional qualifications;
  • promoting physics through scientific conferences, education and science policy advice.

The Institute is a member of the Science Council, and a nominated body of the Engineering Council. The Institute works in collaboration with national physical societies and plays an important role in transnational societies such as the European Physical Society and represents British and Irish physicists in international organisations. In Great Britain and Ireland the Institute is active in providing support for physicists in all professions and careers, encouraging physics research and its applications, providing support for physics in schools, colleges and universities, influencing government and informing public debate.

Einstein Year is here - be inspired by physics in 2005. www.einsteinyear.org


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