New gene test to detect risk of mouth cancer
A breakthrough new gene test can detect pre-cancerous cells in patients with benign-looking mouth lesions.
Oral and pharyngeal cancer is the seventh most common cancer in Europe and ranks ninth in terms of cancer death. In 2004, there were an estimated 67,000 incident cases and 26,000 deaths; and there is concern over its increasing prevalence in eastern Europe.
Researchers at Queen Mary, University of London in the United Kingdom have developed a test that could potentially allow at-risk patients to receive earlier treatment, significantly improving their chance of survival.
Oral cancer develops in any of the parts that make up the mouth. This includes the lips, gums, tongue, inside lining of the cheeks, and the roof and floor of the mouth. It can also be called oral cavity cancer or mouth cancer.
Mouth cancer is one of several types of cancer grouped in a category called head and neck cancers, which are often treated similarly. In the United Kingdom alone, mouth cancer affects more than 6,200 people each year and more than half a million people worldwide. Worldwide, the figure is expected to rise above 1 million a year by 2030. The majority of cases can be traced back to either smoking or chewing tobacco and drinking alcohol.
The research study showed that the quantitative Malignancy Index Diagnostic System (qMIDS) test had a cancer detection rate of between 91 per cent and 94 per cent when used on more than 350 head and neck tissue specimens from 299 patients in the UK and Norway. Their results were published online in the International Journal of Cancer.
Mouth lesions are very common; only 5 per cent to 30 per cent of these turn into cancers. And in most cases, if detected in the early stages, treatment can be curative. Until now, however, there has not been a test that able to accurately detect which lesions will become cancerous.
The current diagnostic gold standard is histopathology. In this test, a biopsy tissue taken during an operation is examined under a microscope by a pathologist. This is a relatively invasive procedure, and most of the mouth cancers being diagnosed are in later stages, when the chances of survival are significantly reduced. For patients diagnosed with advanced onset of the disease, survival rates are poor, between approximately 10 per cent and 30 per cent at 5 years.
'A sensitive test capable of quantifying a patient's cancer risk is needed to avoid the adoption of a "wait-and-see" intervention. Detecting cancer early, coupled with appropriate treatment can significantly improve patient outcomes, reduce mortality and alleviate long-term public healthcare costs,' said lead investigator and inventor of the test, Dr Muy-Teck Teh from the Institute of Dentistry at Queen Mary, University of London.
What the qMIDS test essentially does is measure the levels of 16 genes, which are converted, via a diagnostic algorithm, into a 'malignancy index' that quantifies the risk of the lesion becoming cancerous. According to the researchers, it is less invasive and faster than the standard histopathology methods. It requires only a 1 mm to 2 mm piece of tissue (less than half a grain of rice), and it takes less than three hours to produce results, compared to the standard histopathology waiting time of up to a week.
Consultant oral and maxillofacial surgeon, Professor Iain Hutchison, founder of Saving Faces and co-author of the study, was enthusiastic about their results and the implications for patients. 'We are excited about this new test, as it will allow us to release patients with harmless lesions from regular follow-up and unnecessary anxiety, whilst identifying high-risk patients at an early stage and giving them appropriate treatment. Mouth cancer, if detected early when the disease is most receptive to surgical treatment, has a very high cure rate.'
Dr Catherine Harwood, a consultant dermatologist and a co-author of the study, went on to add: 'Our preliminary studies have shown promising results, indicating that the test can potentially also be used for identifying patients with suspicious skin or vulva lesions, offering the opportunity of earlier and less invasive treatments.'
Whilst this proof-of-concept study validates qMIDS as a diagnostic test for early cancer detection, further clinical trials are required to evaluate the long-term clinical benefits of the test for mouth cancers.
With further development, it could potentially be applied to other cancer types, as the test is based on a cancer gene, FOXM1, which is highly expressed in many cancer types. In this study, the researchers used the qMIDS test to detect early cancer cells in vulva and skin specimens with promising results.
Dr Teh's earlier research conducted on FOXM1 was awarded 'Molecule of the Year 2010' by the International Society for Molecular and Cell Biology and Biotechnology Protocols and Research. That research showed that when FOXM1 is overexpressed, the protein loses its control over cell growth, allowing cells to proliferate abnormally.
For more information, please visit:
The Institute of Dentistry at Queen Mary, University of London:
International Journal of Cancer:
Data Source Provider: The University of London
Document Reference: Based on information from the University of London
Subject Index: Coordination, Cooperation; Life Sciences; Medicine, Health; Scientific Research