Neslihan Bascil Tutuncu

Prevalence and prediction of malignancy in cytologically indeterminate thyroid nodules

Objective Controversy surrounds the evaluation of nodules with indeterminate cytology results. Malignancy rates in these nodules are not low. We examined the malignancy rates in nodules that showed follicular neoplasm or atypical cells on cytology and attempted to predict malignancy based on ultrasonographic features.

Clinical and epidemiological characteristics of thyroid hemiagenesis: ultrasound screening in patients with thyroid disease and normal population

Thyroid hemiagenesis is a rare form of thyroid dysgenesis, in which one thyroid lobe fails to develop. The true prevalence of this rare abnormality is about 0.05–0.2% in normal population. We aimed to determine prevalence of thyroid hemiagenesis in patients with various thyroid disorders and a normal population in a mild to moderate iodine-deficient area. The clinical and thyroid ultrasonography records of 4,833 patients who presented with various thyroid disorders were reviewed. In addition, ultrasonographic data of two large surveys carried out for the community screening of iodine status of children (nxa0=xa04,772) and thyroid disorders of adult subjects (nxa0=xa02,935) were analyzed. In patients with thyroid disorders, we found 12 cases with thyroid hemiagenesis (0.25%). Thyroid hemiagenesis was due to the agenesis of the left lobe in all cases. The underlying thyroid diseases were Hashimoto’s thyroiditis (nxa0=xa04), euthyroid multinodular goiter (nxa0=xa04), and toxic adenoma (nxa0=xa01). Three subjects have no underlying thyroid disease. In ultrasonography screening of normal population, altogether, the absence of the left lobe was detected in only two cases, indicating a true prevalence of thyroid hemiagenesis of 0.025%. None of the reviewed patients had thyroid dysfunction. Our community-based data is in accordance with previous studies in terms of prevalence and male-to-female ratio.

Ultrasound-guided fine-needle aspiration biopsy and ultrasonographic features of infracentimetric nodules in patients with nodular goiter: Correlation with pathological findings

We evaluated the usefulness of ultrasound-guided fine-needle-aspiration biopsy (US-FNAB) for infracentimetric nodules. In addition, we used sonography to assess the risk of malignancy of thyroid nodules, and we evaluated the extent of disease in infracentimetric cancers. The cytopathological results of 472 US-FNABs from 207 nodular goiter patients (170 women, 37 men; mean age, 51.5±13.1 yr) seen between 1999 and 2004 were categorized into five groups: inadequate, benign, suspicious, follicular neoplasm, and malignant. There were 145 infracentimetric nodules and 327 supracentimetric nodules. All patients underwent surgery. Final histopathological results correlated with cytologic results. The sensitivity, specificity, positive predictive value, negative predictive vallue, and accuracy of US-FNAB for infracentrimetric nodules were 96.3%, 71.2%, 44.8%, 98.8%, and 76.1%; and for supracentimetric nodules, these values were 98.1%, 63.1%, 35.6%, 99.4, and 69.1%, respectively. There were no significant differences between infracentimetric and supracentimetric nodules. More thyroid cancer could be detected in infracentimetric nodules that were hypoechoic or had fine calcification on ultrasonography (which may be helpful in discriminating which nodules are appropriate for FNAB) than in supracentimetric nodules. However, logistic regression analyses showed that no single variable was predictive of malignancy in infracentimetric nodules. The malignancy rate in infracentimetric nodules was 21.4%. In this subgroup, 4 of 31 patients (12.9%) had multifocal tumors at surgery, 3 of 31 had extrathyroidal invasion, and 1 had a metastasis to the lung. In addition, at surgery, 11 of 55 tumors (20%) larger than 1 cm were multifocal. In conclusion, small tumor size does not guarantee a low risk of thyroid cancer, and US-FNAB may be useful tool for diagnosing malignant infracentimetric nodules.

The analgesic efficacy of lidocaine/prilocaine (EMLA) cream during fine‐needle aspiration biopsy of thyroid nodules

Objectiveu2002 Pain is one of the few drawbacks of fine‐needle aspiration biopsy (FNAB) in patients with nodular thyroid disease (NTD). Lidocaine/prilocaine cream, an eutectic mixture of local anaesthetics (EMLA), is a frequently used topical anaesthetic. Despite its well‐documented efficacy for the relief of pain associated with other cutaneous procedures that involve needle insertion, the analgesic role of EMLA has not been previously reported in patients with NTD who are undergoing FNAB. The aim of this study was to determine the analgesic efficacy of EMLA for FNAB‐associated pain in patients with NTD.

Repaglinide plus single-dose insulin glargine: a safe regimen for low-risk type 2 diabetic patients who insist on fasting in Ramadan

Aim of this prospective study is to evaluate the effect of repaglinide t.i.d. (three times a day) plus single-dose insulin glargine regimen in low-risk type 2 diabetic patients during Ramadan fasting. Participants had been taking the regimen for at least 3xa0months. Patients with a history of diabetic coma, severe hypoglycemic crisis or repeating attacks of hypoglycemia were excluded. Hypoglycemic unawareness, kidney or liver disease or HbA1c over 8% were also accepted as exclusion criteria. Eleven patients who insisted on this worship and eight non-fasting cases were involved. All were told to make home-glucose-monitorisation weekly and report any hypoglycemic event throughout Ramadan. Fasting blood glucose (FBG), post-prandial blood glucose (PBG) and fructosamine levels, body weights and blood pressures were recorded just before and after Ramadan. Seven patients in each group concluded the follow-up. Any significant change was detected in the parameters in either groups (Pxa0>xa00.05). Glucose control remained unchanged; fructosamine 318.14xa0±xa065.38 versus 317.28xa0±xa052.80xa0mmol/L in fasting group, 290.71xa0±xa038.48 versus 290xa0±xa038.56xa0mmol/L in non-fasting group. None of them exhibited either a major or a minor hypoglycemic event. The results of this pilot study indicated that repaglinide t.i.d. plus single-dose insulin glargine regimen was safe for low-risk type 2 diabetic patients who insisted on fasting during Ramadan.

Subclinical Hypothyroidism Is Characterized by Increased QT Interval Dispersion among Women

Objective: Increased QT interval dispersion (QTd) is an electrocardiographic parameter shown to be associated with malignant ventricular arrhythmias and sudden death, and QT dispersion corrected for heart rate (QTc) has emerged as a potentially important predictor of cardiac death. Increased QTd has been detected to be directly related to thyroid-stimulating hormone (TSH) levels in overt hypothyroidism, however not much is known about subclinical hypothyroidism (SH). This study was conducted to investigate the QTc in SH and determine the changes following normalization of TSH levels with L-thyroxine. Subjects and Methods: Fifty-eight women with naive SH due to Hashimoto’s thyroiditis, mean age 39.37 ± 10.43 years, and 54 age-, sex- and weight-matched controls with normal TSH were included after exclusion of any factor that might interfere with cardiac conductibility. Electrocardiographic measurements were performed with a magnifier and Bazett’s formula was used to calculate QTc. The patients were separated into two groups regarding basal TSH levels (subgroup A: 5 > TSH > 10 mIU/l, n = 36; subgroup B: TSH > 10 mIU/l, n = 22). L-Thyroxine 1–2 µg/kg/day was administered to subgroup B. Results: Mean QTc interval of the study group was significantly longer than that of the control group (100 ± 30 vs. 76 ± 30 ms, p = 0.000). It was also longer in subgroup A (5 > TSH > 10 mIU/l, n = 36) and subgroup B (p = 0.001, p = 0.000, respectively). In subgroup B, following normalization of serum TSH, mean post-treatment QTc measurement was similar to that of the control group (75 ± 40 vs. 76 ± 30 ms, p > 0.05). Conclusion: We detected prolonged QTc among SH cases. Prolongation remained significant for the whole group as well as the two subgroups. The differences in QTc were corrected when TSH levels of >10 mIU/l returned to normal.

Thyroid cancer in hyperthyroidism: Incidence rates and value of ultrasound-guided fine-needle aspiration biopsy in this patient group

Three hundred and thirty-three hyperthyroidism cases were retrospectively investigated to provide information about the association between hyperthyroidism and thyroid cancer. There were 112 cases of toxic multinodular goiter (TMNG), 77 cases of toxic nodular goiter (TNG) and 144 cases of Graves’ disease (GD). All nodules detected in GD patients, all nodules greater than 1 cm diameter in nodular goiter patients, nodules 5–10 mm size diameter if they had calcification were fine-needle biopsied (FNAB) under ultrasound guidance (US-guided), and a total of 612 such biopsies were performed. The biopsy samples were cytologically assessed as benign (no.=552; 90.2%), suspicious (no.=6; 1.1%), malignant (no.=13; 2.1%), or inadequate for diagnosis (no.=41; 6.7%). All patients with a biopsy diagnosis of malignant or suspicious nodules underwent surgery. Histological examination confirmed the diagnosis of thyroid cancer in all 13 (2.1%) patients with malignant FNAB findings. Papillary thyroid carcinoma (PTC) was identified in 2 patients with TMNG (%1.8), 5 with TNG (%6.5) and 5 with GD (%3.5). Metastatic follicular thyroid carcinoma (FTC) was identified in a patient with TNG. Thyroid malignancy (micro- or macrocarcinoma) was diagnosed pre-operatively in all 13 cases by US-guided FNAB. Thyroid cancer was diagnosed in 6 (5.5%) of the 109 nodules detected in the TNG group, 2 (0.44%) of the 452 nodules detected in the TMNG group, and 5 (9.8%) of the 51 nodules detected in the GD group. Two (2.6%) of the 77 functioning nodules in the TNG patients were malignant, but none of the 402 functioning nodules in the TMNG patients was malignant. In patients with hyperthyroidism, US-guided FNAB is useful for detecting thyroid cancer in nodules greater than 5 mm diameter before radioiodine therapy or surgery.

Cyclin A and cyclin B1 overexpression in differentiated thyroid carcinoma.

Approximately 30% of patients with thyroid nodules have indeterminate or suspicious fine-needle aspiration (FNA) biopsy results. These patients usually undergo thyroidectomy because of cancer risk. Our aim was to determine diagnostic value of cyclin A and cyclin B1 immunohistochemistry added to routine cytology and their expression on histological sections. We studied the expression of cyclin A and cyclin B1 in FNA biopsies and resection specimens of 168 indeterminate or suspicious FNA biopsy results retrospectively at an academic hospital using immunohistochemistry. Malignant histopathology consisted 64 of resection specimens (58 papillary, 4 follicular, 1 medullary, and 1 Hürthle cell carcinoma). Cyclin A was overexpressed in 51.5% of malignant cases in contrast to 31.7% of 104 benign pathology specimens (Pxa0=xa00.025). Cyclin B1 was positive in 39.1% of malignant specimens in contrast to 15.4% of benign cases (Pxa0=xa00.001). Cyclin A overexpression was not linked to cyclin B1 overexpression. No association was found between overexpression of cyclin A, cyclin B1 and age, thyroiditis, multifocality, tumor size, extra-thyroidal extension, capsule infiltration, lymph node and distant organ metastases and TNM stage in malignant cases. Female patients with thyroid carcinoma overexpressed significantly more cyclin B1 than male patients (Pxa0=xa00.015). Retrospective analysis of cyclin A and cyclin B1 in FNA biopsies yielded negative results for both benign and malignant cases. In conclusion, cyclin A and cyclin B1 are useful markers in the distinction of benign and malignant thyroid tumors and can increase diagnostic accuracy.

Radioactive Iodine in the Treatment of Type-2 Amiodarone-Induced Thyrotoxicosis

OBJECTIVEnAmiodarone-induced thyrotoxicosis (AIT) is usually classified into two types: type 1, in which a high iodine content triggers the autonomous production of thyroid hormone; and type 2, in which destructive thyroiditis causes the release of preformed thyroid hormone. AIT is a difficult management problem that sometimes requires ablative thyroid therapy. The use of radioactive iodine (RAI) therapy in patients with type-1 AIT who had a 24-hour radioactive iodine uptake (RAIU) value of >10% has been previously reported. Despite its documented efficacy at usual doses (10-30 mCi) in patients with type-1 AIT, the efficacy of RAI in those with type-2 AIT has never been questioned, because type-2 patients usually have low RAIU. We thought that high adjusted-dose RAI might be an attractive alternative to thyroid gland ablation in patients with type-2 AIT.nnnPATIENTS AND METHODSnFour patients with type-2 AIT who required thyroid ablation were included in the study. These individuals were either poor candidates for surgery or had refused surgery. The size of the thyroid gland in all subjects was within normal limits, and each thyroid was characterized by a homogenous echotexture on ultrasonography, the absence of vascularity on Doppler sonography, a low (<4%) 24-hour RAIU value and the absence of thyroid autoantibodies-all of which are characteristic of type-2 AIT.nnnRESULTSnThe patients were initially treated with thionamides and glucocorticoids. All patients except one achieved euthyroidism before RAI therapy. All four patients received one dose of RAI (range 29-80 mCi) and followed up for 12 months. No exacerbation of thyrotoxicosis was noted after RAI therapy. Hypothyroidism (in three patients) or euthyroidism (in one patient) was achieved in first six months.nnnCONCLUSIONSnIn patients with type-2 AIT, RAI treatment may be the therapy of choice for thyroid gland ablation.

The effect of single-dose orlistat on postprandial serum glucose, insulin and glucagon-like peptide-1 levels in nondiabetic obese patients.

Objectiveu2002 Glucagon‐like peptide‐1 is an insulin secretion‐stimulating gut hormone that is produced in response to food intake. Orlistat (Xenical, F. Hoffman‐La Roche, Basel, Switzerland), which decreases fat absorption and increases intestinal fat content, may therefore affect the secretion of glucagon‐like peptide‐1. In this study we examined the immediate effects of orlistat on postprandial serum glucose, insulin and glucagon‐like peptide‐1 levels prior to a change in body weight.