Are clinicopathological features of the isthmic thyroid nodule different from nodules in thyroid lobes? A single center experience

ABSTRACT Objectives: Thyroid nodules located in isthmus were found less prevalent, although papillary thyroid cancer in this location was reported to be more aggressive behaviour in some studies. Our aim was to evaluate hormonal,ultrasonographic, and cytopathologic features of nodules located in isthmus (isthmic nodules). Subjects and methods: Patients who underwent thyroidectomy between 2006-2014 reviewed retrospectively. Hormonal, ultrasonographic, and cytopathologic features compared between patients with isthmic (Group-1) and with lober (non-isthmic, Group-2) nodules. Results: Group-1 and Group-2 consisted of 251 and 2076 patients, respectively. 260 isthmic (5.5%) and 4433 non-isthmic (94.5%) nodules were compared.However,most ultrasonographical features such as presence of microcalcification and halo, diameters, echogenicity, texture, margin, and vascularity were similar between groups, macrocalcification rate was lower in isthmic nodules (18.8%, 25.9%; p = 0.012). Cytologic results were also similar.Although malignancy rate was lower in isthmic nodules (6.2%, 12.5%; p = 0.002), type of thyroid cancer was similar in isthmic and non-isthmic nodules.When malignant isthmic (n = 16,2.8%) and malignant non-isthmic nodules (n = 553, 97.2%) were compared, diameter and type of tumor, lymphovascular and capsular invasions, extrathyroidal extension and multifocality rates were not statistically significant.Malignant isthmic nodules (n = 16, 6.2%) had smaller size [10.1 (7.5-34.5) mm, 19.95 (8.4-74.1) mm; p = 0.002], and higher hypoechogenicity rate (31.3%, 5.7%, p = 0.003) compared to benign isthmic nodules (n = 244, 93.8%). Negative predictive value was higher and positive predictive value was lower in isthmic nodules compared to non-isthmic nodules (p = 0.033, p = 0.047, respectively). Conclusion: Isthmic nodules appear to be indolent because of having lower malignancy rate. FNAB might be required in isthmic nodules even if it has relatively small size.The surgery with limited extent or follow-up might seem to be reliable in the management of patients having isthmic nodules especially with indeterminate cytology.

Ultrasonographical, clinical and histopathological features of 1264 nodules with papillary thyroid carcinoma and microcarcinoma based on tumor size

ABSTRACT Objective: We aimed to evaluate the patients diagnosed with papillary thyroid carcinoma (PTC) and papillary thyroid microcarcinoma (PTMC) in terms of clinical, ultrasonographical (US) and histopathological features and their relationships with tumor size. Subjects and methods: We retrospectively evaluated 881 patients who underwent thyroid surgery in our clinic and diagnosed with PTC histopathologically were enrolled the study. Demographic characteristics, US findings and histopathological features were evaluated. Results: In total, 1264 nodules were identified in the 881 patients. The incidentality rates were higher in the PTMC group and also in the ≤ 5 mm group. In total multifocality rate was 32.9%, and was significantly higher in PTMC group than the PTC group. PTC and > 5 mm PTMC groups compared to PTMC and ≤ 5 mm groups respectively, were more aggresive histopathological features. Conclusions: Since the incidentality rates were found significantly more common in our patients with PTMC and those with ≤ 5 mm, ultrasonographic features of the nodules should be evaluated carefully and for cases which are suspicious with US, US-guided fine needle aspiration biopsy (FNAB) should be considered in order to make the correct treatment strategy. Also our study revealed that PTC and > 5 mm PTMC groups compared to PTMC and ≤ 5 mm groups respectively, have more aggresive histopathological features.

The association of autoimmune thyroiditis and non-functional adrenal incidentalomas with insulin resistance

Objective Patients with incidental nonfunctioning adrenal adenoma are associated with increased risk of obesity, impaired glucose tolerance and dyslipidemia. We aimed to investigate the relationship between thyroid function, serum lipids and insulin resistance in patients with nonfunctioning adrenal incidentaloma. Subjects and methods Forty patients who had diagnosed as adrenal incidentaloma (AI) in our department were included in the study. Serum free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), anti-thyroperoxidase antibody (anti-TPO Ab) and anti-thyroglobulin antibody (anti-Tg Ab), lipid profile, hs-CRP, fasting insulin levels were measured and insulin resistance calculated by HOMA-IR. Thyroid volume (TV) was assessed. Results None of the patients showed specific signs and symptoms of hormone excess. TV, TSH and fT3 levels in the patient and control groups did not differ significantly (p > 0.05). The serum fT4, anti-TG Ab, anti-TPO Ab levels in the patient group were significantly higher than in the control group (p = 0.013, p < 0.0001, p = 0.016 respectively). The HOMA-IR, hs-CRP and HDL cholesterol levels in the AI patients were significantly higher than the control group (p = 0.034, p = 0.041, p = 0.002, respectively). Statistically significant relationship was found between HOMA-IR and thyroid volume (r = 0.373, p = 0.018), fT4 (r = 0.382, p = 0.015), hs-CRP (r = 0.512, p = 0.001), HDL cholesterol (r = 0,351 p = 0.026) in AI patients. There were significant correlation between anti-TG Ab, anti-TPO Ab and TSH levels in AI patients (r = 0.431 p = 0.006, r = 0.402 p = 0.012). Conclusions Patients with nonfunctioning adrenal incidentaloma have several metabolic disturbances. At the same time autoimmune thyroid disorders are more frequent in nonfunctioning adrenal incidentaloma patient so that thyroid functions must be evaluated in those patients. Arch Endocrinol Metab. 2015;59(1):42-6 .