7466 The Effects of Various Forms of Diabetes on Features of Tumor Aggressiveness in Thyroid Cancer

Abstract Disclosure: R.D. Paparodis: None. E. Karvounis: None. A. Kapezanou: None. S. Livadas: None. G. Simeakis: None. D.P. Askitis: None. I. Androulakis: None. N.G. Angelopoulos: None. D. Zianni: None. A. Rizoulis: None. A. Boniakos: None. I. Perogamvros: None. D. Bantouna: None. J.C. Jaume: None. Introduction: Diabetes has been linked to increased risk for several cancers and aggressiveness of tumor behavior. A link between thyroid cancer and diabetes appears controversial in the literature as of yet. We designed the present study to assess whether autoimmune (type 1 + LADA = DM1) or type 2 diabetes (DM2) are associated with more aggressive thyroid cancers compared to those found in non-diabetic (non-DM) individuals. Methods: We retrospectively reviewed data from patients undergoing thyroid surgery in 10 Endocrinology and Endocrine Surgery Clinics throughout Greece over 2 years. We collected data on history and type of diabetes, pre-existing to the thyroid surgery, its treatments and duration, the preoperative thyroid function tests and the surgical pathology findings. We compared the incidence of various histological types of thyroid cancer and the features of tumor aggressiveness between patients with diabetes and those with normal glucose homeostasis (non-DM) (DM1 vs. DM2 vs. non-DM). Results: Overall, n=808 subjects with thyroid cancer were included: n=571 were females (70.7%), age 47.3 ± 14.3 years, BMI 27.0 ± 5.0 Kg/m[2], mean TSH 1.99 ± 2.21 mIU/L; n= 692 were non-DM, n=10 had DM1 and n=107 had DM2. Histology revealed n=5 poorly differentiated / anaplastic, n=13 medullary, n=12 Hürthle cell, n=17 follicular and n=773 papillary thyroid cancers (PTC); n=20 (2.5%) with aggressive histological subtypes of PTC, n=5 (0.6%) with distant metastases (MET), n=199 (24.6%) with extrathyroidal extension (ETE), n=419 (51.9%) with capsular invasion (CI), n=225 (27.8%) with lymph nodes involvement (LNi) and n=23 with cancer recurrence (CR) (2.8%). The incidence of aggressive histological types, CR, MET or number of I-131 treatments were not different between groups (p>0.05). ETE, CI and LNi were significantly more common in non-DM compared to both diabetes groups, while gross ETE was more common in DM2 over DM1 and non-DM (p