PP13. CHERNOBYL, BREXIT AND BRAIN TUMOURS
Authors: Dr kazumi chia, Ms Rhiannon Davies, Dr Lucy Brazil
Journal: Neuro-Oncology (2017)

Following the 2004 enlargement of the European Union, many hundreds of thousands of people from the newly ascended states travelled to the UK to look for work. Polish workers were by far the largest group and today, Polish is the second most commonly spoken language in the UK. In central London, the multidisciplinary, neuro-oncology team at Guy’s and St. Thomas’ NHS Foundation Trust (GSTFT) and Kings College Hospital serves a catchment area of nearly 3.5 million, 1% (32,253) of whom are recorded to have been born in Poland at the last 2011 census. Over the past few years, we have observed a relatively large number of Polish-born UK residents presenting with primary brain and central nervous system (CNS) tumours. Data collection is ongoing but we believe that the numbers of newly diagnosed cases far exceeds the published age standardized incidence rate for brain and CNS tumors in Poland which is 10 per 100,000. If a higher than expected incidence of brain and CNS tumors in our local Polish population is observed this could be explained by a number of socioeconomic/health factors. However, as we mark the 30th anniversary of the Chernobyl accident this year, we should also keep in mind geohistorical factors that may be relevant to this particular immigrant population. Poland neighbours Ukraine where the Chernobyl accident occurred, and was affected by the radioactive fallout that followed the disaster. The main health impact from Chernobyl has so far been the increased incidence of thyroid cancer but there is now increasing concern about the increased risk of non-thyroid, solid tumors. An increased incidence in CNS tumours has been seen in atomic bomb survivors where even a low exposures (<1Sv) was associated with an increased risk. Cohort studies in Belarus and Ukraine, two countries with the most radiation contamination, have so far not demonstrated any significant increase in non-thyroid cancers but it may still be early days. We know from long term follow up studies of childhood cancers that radiation-induced brain and CNS tumors can present very later, 20, 30 years after initial exposure. Due to the very long half life (30 years) of the main radioisotope responsible for the contamination (Caesium-137), the nature of the exposure is extremely protracted. The World Health Organisation recently issued a press release stating that “protracted exposure to low doses of ionizing radiation increases the risk of death from solid cancers.” People at highest risk of developing solid cancers as a result of radiation exposure due to Chernobyl would be those who were children at the time of the disaster or born just after 1986 when the accident occurred. We will present data showing a range of CNS tumours in our Polish patients including information about geographical location and age at the time of the Chernobyl nuclear accident as well as age of diagnosis of brain tumour. In areas affected by rapidly changing patterns of immigration it is important to be aware of the oncological risk factors associated with the groups that we serve.