An Exploratory Pilot Study of Peripheral Blood MicroRNA Markers in Patients with Papillary Thyroid Cancer, £20000
Dr Petros Perros, Consultant Endocrinologist and Honorary Senior Lecturer with Professor Simon Pearce, Professor of Endocrinology, Newcastle University
About 2,500 people are diagnosed with thyroid cancer in the UK every year. It is one of the fastest rising cancers among women. The majority of people who are diagnosed with thyroid cancer survive for many years, but have to have checks regularly as the cancer can return even after 30 years after the original diagnosis. So, about 30,000 people in the UK visit thyroid cancer clinics regularly and will continue to do so for the rest of their lives. Doctors have a very useful blood test available called a "thyroglobulin test", which can signal early if the thyroid cancer is beginning to come back. So a negative thyroglobulin test is very reassuring for both patient and doctor and such patients can be followed up less frequently. Unfortunately, the thyroglobulin blood test in about a third of people with thyroid cancer is made useless by the presence of antibodies in the blood stream. So, for about 10,000 people who have been treated for thyroid cancer in the UK the thyroglobulin blood test is useless. Doctors can identify these patients because of the positive antibody test, but they have to rely on other ways to safeguard against the possibility of the thyroid cancer coming back, which are not as user-friendly as a blood test. Such patients usually have to visit the clinic more frequently for an examination of the neck, have to have frequent ultrasound examinations and in some cases more invasive tests such as radioiodine scans or CT scans that involve exposure to radiation. The burden on the lives of these patients imposed by the uncertainty about their cancer and the additional tests, is significant and impacts on quality of life.
Since the thyroglobulin blood test was invented in the early 1980s no other better diagnostic test has been forthcoming. Recently a potential breakthrough was discovered. A group from China found another marker in the blood of patients with thyroid cancer, which was present in patients before they were treated and disappeared after successful treatment. This test is not interfered with by antibodies so, potentially it can be very useful for the 10,000 people in the UK mentioned above. This new test detects chemicals called 'microRNAs'. They are thought to be released by circulating cancer cells. The work by the Chinese group is encouraging but needs to be confirmed and refined further. We believe that our research group is in an ideal position to do just that. We have already 400 blood samples collected from patients with thyroid cancer, some of whom have been cured while others still have cancer. We plan to use a laboratory in Denmark who are at the cutting edge of this technology. So, we believe that this project will be a good start and will provide some valuable information with minimum delay, which can then be expanded further, with a view to developing a diagnostic blood test that can be applied reliably to all patients with thyroid cancer, and can tell us if they are cured or if the cancer is still in their body. Uncertainty is a terrible predicament for people with a history of cancer. We believe that our research could potentially have a huge positive impact on the lives of people with thyroid cancer.