S S85 Comparisons with historical cohorts from this region shows a significant increase in the proportion of DTC (65% in the 1960s, 58% in the 1980s and 87% currently. Conclusion: The incidence of thyroid cancer in South Yorkshire is lower than many other parts of Europe. Age and gender distribution of each type is similar to published series and the causes of increased incidence are explored. http://dx.doi.org/10.1016/j.ejso.2015.08.094 19. Parathyroidectomy in Pregnancy: A single centre 10-year experience Paul C. Dent, Niyati Lobo, Susan Kirby, Neil S. Tolley, F.Fausto Palazzo Hammersmith Hospital, Imperial College Healthcare NHS Trust, UK Introduction: Primary hyperparathyroidism (PHPT) affects approximately up to 0.15% of the population with an almost 3:1 female to male ratio. However the prevalence of PHPT in women under the age of 40 is thought to be less than 4/10,000. It is suggested that PHPT in pregnancy in addition to the standard morbidity is associated with a risk of miscarriage and fetal death but best practice is not evidence based. We present our 10 year experience of parathyroidectomy performed during pregnancy. Methods: We retrospectively reviewed a prospectively maintained audit database of all cases of parathyroidectomy performed between 2005 and 2015 and identified operations performed in pregnant women. Data analysed include patient demographics, clinical features, preand post-operative biochemical studies, radiological and pathological findings, and outcome of pregnancy. Results: 932 parathyroidectomies were performed for PHPT between 2005e2015 and 12 women (aged 34.9 4.1 years) were pregnant at the time of surgery. The mean corrected calcium was 2.96 0.19 mmol/L with a PTH 16.7 10.6 pmol/L. Ultrasound localization was performed in all patients prior to surgery and 4/13 were helpful in localizing the correct parathyroid gland. Parathyroidectomy was performed with an obstetric anaesthetist. 12 patients were in the second trimester and 1 in the early third trimester (19.7 3.6 weeks). Anaesthetic time was 61.3 16.7minutes. Cure was achieved in 11 patients at first surgical intervention with no reported complications at follow up. The one patient with mild persistence/recurrence (normal corrected calcium and PTH level immediately post-operatively with an unaccommodated PTH at 6 months), had undergone a minimally invasive parathyroidectomy under LA. All foetus’ had a normal pre& post operative heart monitor. There were no immediate maternal or foetal complications and all completed their pregnancy. Conclusion: Parathyroidectomy during pregnancy is safe with obstetric anaesthesia. The absence of nuclear imaging makes four gland visualisation the approach most likely to achieve permanent cure. http://dx.doi.org/10.1016/j.ejso.2015.08.095 20.Anatomic study of the external branch of the superior laryngeal nerve. Anatomic findings and its implication in thyroid surgery Xenophon Kochilas, Konstantinos Argiris, Thanos Bibas 1 Brighton and Sussex Universities NHS Trust, UK Hippocration University Hospital Athens Greece, Honorary Reader in Otolaryngology, Ear Instituted UCL, London, UK Introduction: The External Branch of the Superior Laryngeal Nerve (EBSLN) has been described as the “neglected” in thyroid surgery. The purpose of this study was to describe the topography of the EBSL and its relationship to the adjacent anatomical structures. Material and Methods: 21 formalin-embalmed human cadavers of both sexes ranging in age from 52 to 94 (mean, 78 years) were included in this study. A total of 42 superior thyroid poles (SPT) were dissected and the exact course of the EBSLN was identified and its relationship to: i) the superior pole of the thyroid gland (SPTG) ii), the superior thyroid vessels (STV), and iii) the inferior constrictor muscle of pharynx (ICMPH) was noted. Results: The EBSLN was identified in 41 specimens (97.61%). In (19.04%) the EBSLN was crossing the STV > 1 cm above the SPTG In (54.76%) the EBSLN was crossing the STV A at 9q22.23 in a Western European cohort of patients with thyroid cancer compared to controls. Methods: DNAwas extracted from buccal swabs or whole blood of patients with differentiated non-medullary thyroid cancer by ethanol precipitation. Patients were recruited from two tertiary referral centres in Ireland and France. Cancer-free controls were recruited from the community. Genotyping was performed using Taqman-based PCR. Data was analysed using SPSS V22. Results: One hundred and eighty one cases and eighty-three controls were genotyped for the variant. The frequency of the minor allele among cases was 0.46 compared to 0.31 among controls. The genotypic odds ratio for heterozygous carriers was 2.41 (1.36e4.26, p 1⁄4 0.002), increasing to 3.56 (1.48e8.53, p 1⁄4 0.003) for rare homozygotes. Conclusion: The FOXE1 variant was identified in patients with thyroid cancer significantly more frequently than controls in both heterozygous and homozygous forms. An allele dosage effect was observed, with rare homozygous genotype conferring greater risk than heterozygotes. http://dx.doi.org/10.1016/j.ejso.2015.08.097 22. Investigating the role of polymorphism rs2910164 in mir146a in cancer predisposition Terri P. McVeigh, Patrick W. Owens, Robert Mulligan, Nicola Miller, Carole Guerin, Frederic Sebag, Denis Quill, Marcia Bell, Aoife J. Lowery, Joanne B. Weidhaas, Michael J. Kerin 1 Department of Surgery, Galway University Hospital, Galway, Ireland Department of Clinical Genetics, Our Lady’s Children’s Hospital Crumlin, Dublin, Ireland Department of Endocrine Surgery, Hopital de la Timone, Marseilles, France