New 'fluid biopsy' can spotlight cancer cells
Published 04/02/2012 | 05:00
Cancer treatment could be transformed by a new "fluid biopsy" technique that spotlights tumour cells carried in the bloodstream, say scientists.
Researchers in the US have developed a way of attaching fluorescent "tags" to cancer cell proteins, making them glow under special light conditions.
The technique, successfully tested in patients with breast, prostate and pancreatic cancer, paves the way to "real time" assessment and treatment of the disease.
Study author Professor Peter Kuhn, from Scripps Research Institute in La Jolla, California, said: "In the future, our fluid biopsy can effectively become the companion to the patient for life.
"If we can assess the disease in real time, we can make quantitative treatment decisions in real time. These decisions include predictive decisions about therapeutic response, diagnostic decisions and prognostic decisions about outcome."
Fluid biopsies will also be an invaluable tool for scientists that can help them unravel the mysteries of metastasis, the deadly spread of cancer from one part of the body to another, it is claimed.
The system uses dyes containing antibodies that bind to specific proteins found in circulating tumour cells (CTCs) in blood samples.
Once attached to the cancer cells they fluoresce in different colours, allowing the cells and proteins to be identified.
The resulting high resolution microscope images reveal intricate details of the cells that can be analysed.
Tests of the technique found five or more CTCs per millilitre of blood in 80pc of 20 prostate cancer patients, 70pc of 30 breast cancer patients, and 50pc of 18 pancreatic cancer patients.
The findings are published in the Institute of Physics journal 'Physical Biology'.
Dr Kelly Bethel, senior clinical investigator in Prof Kuhn's team, said: "The high definition method gives a detailed portrait of these elusive cells that are caught in the act of spreading around the body. It's unprecedented -- we've never been able to see them routinely and in high definition like this before."
Dr Larry Nagahara of the US National Cancer Institute, which set up the research under its Physical Sciences in Oncology initiative, said: "The science behind this approach, and the ability to obtain more detailed information about CTCs in a timely fashion, opens up opportunities to address some of the outstanding problems in cancer, such as drug-resistance.
"Bringing a physical sciences approach to a medical need has potential for profound consequences to greatly benefit cancer patients."
Ciaran Devane, chief executive of Macmillan Cancer Support in the UK, said: "We know the numbers of people getting this disease is increasing and these figures by the World Cancer Research Fund should signal alarm bells for the NHS and how we plan future cancer services.
"Macmillan Cancer Support's own research showed that four in 10 people will now get cancer in their lifetime.
"After treatment ends, many patients feel abandoned by the NHS as they struggle to cope with the long-term effects of cancer treatment.
"We need services which keep people well and at home, not services which sort the problem when people arrive at A&E."