Acute exposure to zinc oxide nanoparticles critically disrupts operation of the respiratory neural network in neonatal rat.

Due to their extremely small size that gives them unique physicochemical properties, nanoparticles (NPs) are used in the production of everyday materials. However, NPs can accumulate in body organs and could cause various diseases. Moreover, NPs that cross biological membranes such as the blood-brain barrier can aggregate in the brain and potentially produce neuronal damage. Although studies have reported the effects of diverse NPs on the bioelectrical properties of individual neurons, their potential influences on the operation of whole neuronal networks have not been documented. Here, we aimed to evaluate the effects of an acute exposure to zinc oxide (ZnO) NPs on the central neural networks responsible for mammalian respiratory rhythm generation. Using an isolated ex vivo brainstem-spinal cord preparation from neonatal rat in which the circuitry for the central respiratory command remained intact, we show that ZnO NPs accelerate, then profoundly disrupt respiratory-related activity produced by the pre-Bötzinger complex (preBötC) responsible for inspiratory rhythm generation. Consequently, a sudden and definitive cessation of respiratory-related activity occurs in ZnO NPs-exposed preparations. Part of these effects is related to zinc ions released from NPs. Using brainstem slice preparations containing the preBötC network, whole-cell patch-clamp recordings revealed that ZnO NPs depolarize preBötC inspiratory neurons and affect their bioelectrical properties by reducing the amplitude of action potentials, thereby leading to a depression of intra-network activity and the ultimate termination of respiratory rhythmogenesis. These findings support the conclusion that ZnO NPs may have deleterious effects on the central respiratory centers of newborn mammals.

Predictivity of clinical, laboratory and imaging findings in diagnostic definition of palpable thyroid nodules. A multicenter prospective study.

PURPOSE: To assess the role of clinical, biochemical, and morphological parameters, as added to cytology, for improving pre-surgical diagnosis of palpable thyroid nodules. METHODS: Patients with a palpable thyroid nodule were eligible if surgical intervention was indicated after a positive or suspicious for malignancy FNAC (TIR 4-5 according to the 2007 Italian SIAPEC-IAP classification), or two inconclusive FNAC at a ≥3 months interval, or a negative FNAC associated with one or more risk factor. Reference standard was histological malignancy diagnosis. Likelihood ratios of malignancy, sensitivity, specificity, negative (NPV), and positive predictive value (PPV) were described. Multiple correspondence analysis (MCA) and logistic regression were applied. RESULTS: Cancer was found in 433/902 (48%) patients. Considering TIR4-5 only as positive cytology, specificity, and PPV were high (94 and 91%) but sensitivity and NPV were low (61 and 72%); conversely, including TIR3 among positive, sensitivity and NPV were higher (88 and 82%) while specificity and PPV decreased (52 and 63%). Ultrasonographic size ≥3 cm was independently associated with benignity among TIR2 cases (OR of malignancy 0.37, 95% CI 0.18-0.78). In TIR3 cases the hard consistency of small nodules was associated with malignity (OR: 3.51, 95% CI 1.84-6.70, p < 0.001), while size alone, irrespective of consistency, was not diagnostically informative. No other significant association was found in TIR2 and TIR3. CONCLUSIONS: The combination of cytology with clinical and ultrasonographic parameters may improve diagnostic definition of palpable thyroid nodules. However, the need for innovative diagnostic tools is still high.

Intraoperative neuromonitoring in thyroid surgery: Is the two-staged thyroidectomy justified?

BACKGROUND: The aim of this study was to evaluate the diagnostic accuracy of intraoperative neuromonitoring (IONM) in predicting postoperative nerve function during thyroid surgery and its consequent ability to assist the surgeon in intraoperative decision making. MATERIALS AND METHODS: A total of 2365 consecutive patients were submitted to thyroidectomy by the same surgical team. Group A included 1356 patients (2712 nerves at risk) in whom IONM was utilized, and Group B included 1009 patients (2018 nerves at risk) in whom IONM was not utilized. RESULTS: In Group A, loss of signal (LOS) was observed in 37 patients; there were 29 true positive, 1317 true negative, 8 false positive, and 2 false negative cases. Accuracy was 99.3%, positive predictive value was 78.4%, negative predictive value was 99.8%, sensitivity was 93.6%, and specificity was 99.4%. A total of 29 (2.1%) cases of unilateral paralysis were observed, 23 (1.7%) of which were transient and 6 (0.4%) of which were permanent. Bilateral palsy was observed in two (0.1%) cases requiring a tracheostomy. In Group A, 31 (2.3%) injuries were observed, 25 (1.8%) of which were transient and 6 (0.4%) of which were permanent. In Group B, 26 (2.6%) unilateral paralysis cases were observed, 20 (2%) of which were transient and 6 (0.6%) of which were permanent; bilateral palsy was observed in 2 (0.2%) cases. In Group B, 28 (2.8%) injuries were observed, 21 (2.1%) of which were transient and 7 (0.7%) of which were permanent. Differences between the two groups were not statistically significant. CONCLUSIONS: Our results show that IONM has a very high sensitivity and negative predictive value, but also good specificity and positive predictive value. For these reasons, in selected patients with LOS, the surgical strategy should be reconsidered. However, patients need to be informed preoperatively about potential strategy changes during the planned bilateral surgery. Future larger and multicenter studies are needed to confirm the benefits of this therapeutic strategy.

Risk of malignancy in thyroid nodules classified as TIR-3A: What therapy?

BACKGROUND: The aim of the present study was to assess the clinical applicability of the TIR3A category in managing thyroid nodules, to examine the malignancy rates of TIR 3A and TIR 3B nodules, and to suggest management guidelines for these nodules. MATERIALS AND METHODS: Thyroid cytologies performed in patients referred to our Department between January 2014 and August 2016 were classified according to the guidelines published by the SIAPEC. 102 cases were included in this retrospective study and were divided into two groups: 19 TIR3A were included in group A and 83 TIR3B in group B. RESULTS: In group A, malignancy was diagnosed in 4 (21.1%) cases, papillary thyroid cancer was found in 3 patients and follicular thyroid cancer in 1; one case was classified as microcarcinoma, in two cancer was multicentric and bilateral and in one central node metastases were observed. In Group B malignancy was diagnosed in 48 (57.8%) patients, papillary thyroid cancer was found in 36 patients and follicular cancer in 12; microcarcinoma was observed in 25 cases, 12 were unilateral multicentric and 7 bilateral multicentric; in 3 cases central node metastases were present. CONCLUSION: Thyroid nodules with TIR3A cytology have a lower risk of malignancy than TIR3B cases, for which the new SIAPEC classification has proved accurate and effective. Malignancy rates in nodules with TIR3A cytology are higher than expected, although the real and accurate definition of the risk is extremely difficult. The recommendation to perform an accurate follow-up and repeat the fine-needle aspiration still appears the best option. For better management of patients with TIR3A cytology a careful assessment of risk factors and ultrasound characteristics is always needed. Further multicenter studies with longer follow-up are needed to better define the efficacy of this classification, the actual cancer risk, and the best management of these lesions.

Parathyroidectomy for primary hyperparathyroidism in the elderly: experience of a single endocrine surgery center.

BACKGROUND: Primary hyperparathyroidism is a common endocrine disease, and its incidence increases with age. AIMS: Our aim was to retrospectively evaluate the impact of age on patient outcomes following parathyroidectomy for primary hyperparathyroidism. METHODS: Two-hundred fifty-six consecutive patients undergoing parathyroidectomy with preoperative diagnosis of primary hyperparathyroidism were divided into three groups according to patient age: group A, ≤64 years; group B, 65-74 years; and group C, ≥75 years. RESULTS: Thyroid disease was associated with the hyperparathyroidism in 44 patients (28.2%) in group A, 34 (44.7%) in B, and 10 (41.7%) in C (p < 0.01). Minimally invasive parathyroidectomy was performed in 104 patients (66.7%) in group A, 35 (46.1%) in B, and 8 (33.3%) in C (p < 0.01). Conversion to bilateral exploration was carried out in five cases in group A (4.6%), three in B (8.3%), and two in C (20%). Multiglandular disease was observed in six patients (3.8%) in group A, seven (9.2%) in B, and five (20.8%) in C (p = 0.012). Mean postoperative stay was similar between groups; no major complications and no cases of mortality occurred. DISCUSSION: Multiglandular disease is more common in older patients than younger individuals, and minimally invasive approaches are less used in this patient group. Increased surgical risk and paucity of symptoms in these patients sometimes result in a delay in surgical treatment. CONCLUSIONS: Parathyroidectomy is a safe and effective procedure to perform in elderly patients. Multiglandular disease was found to be more prevalent in older patients, but minimally invasive parathyroidectomy can be performed safely. Surgeons should consider parathyroidectomy in patients with primary hyperparathyroidism regardless of age.

Differentiated thyroid cancer in patients ≥75 years: Histopathological features and results of surgical treatment.

INTRODUCTION: The aim of this retrospective study was to investigate clinical and pathologic characteristics of differentiated thyroid cancer (DTC) in patients ≥75 years and to analyze results of surgical treatment in this age group. METHODS: The clinical records of patients submitted to total thyroidectomy between 2009 and 2014 with histopathological diagnosis of DTC were analyzed. Patients were divided into 3 groups: patients ≤64 years were included in group A, those between 65 and 74 in B and those ≥75 years in C. RESULTS: Classic papillary thyroid cancer was more frequent in group A, whereas follicular variant of papillary carcinoma, tall cell and follicular carcinoma were more frequent in C. Multicentric and locally invasive tumors were more frequent in group C; younger patients (group A) showed higher incidence of node metastases (12.54% in group A, 6.33% in B and 7.89% in C). Postoperative stay was significantly longer in group C (3.13 ± 1.28 days vs 2.55 ± 1.27 vs 2.89 ± 1.27; p < 0.001). Transient hypoparathyroidism was more frequent in groups A and B compared with C (29.26% vs 19.71% vs 18.42%; p 0.033) whereas transient recurrent laryngeal nerve palsy was more frequent in group C compared with A and B (2.63% vs 0.16% vs 2.11% p 0.009). CONCLUSIONS: In aging patients DTC show a worse prognosis compared with younger patients due to higher incidence of more aggressive histotypes but also to a significant diagnostic delay. Total thyroidectomy is safe when surgical operation is performed by skilled surgeons. Age alone does not exclude surgical option.

Feasibility of unilateral parathyroidectomy in patients with primary hyperparathyroidism and negative or discordant localization studies.

The purpose of this study was to examine the feasibility of unilateral parathyroidectomy in patients with primary hyperparathyroidism and negative or discordant localization studies. We included in our study 72 patients with preoperative diagnosis of primary hyperparathyroidism who had negative or discordant preoperative studies. In 66 patients, studies were discordant while in six were both negative. In 40 (55.6 %) patients initial approach was a bilateral exploration. In 32 cases (44.4 %) initial surgery was a unilateral exploration: in 26 conservative approach was successful, in six mini-invasive surgery failed and a bilateral exploration was necessary due to IOPTH negative test (five cases) or to the impossibility to find a pathological gland during exploration (one case). Intra-operative PTH test showed a sensitivity of 93.2 %, a specificity of 92.3 %, and an accuracy of 93.1 %. Multiple gland disease was found in 8 (11.1 %) patients (two double adenoma and six multiple gland hyperplasia). Mean operative time was lower in unilateral exploration group (87.9 ± 43.8 min). Comparing unilateral surgery in negative or discordant studies with 77 consecutive patients who underwent focused surgery with positive and concordant studies, conversion to bilateral exploration rate was statistically significantly higher in the first group (15.6 %). We believe that unilateral parathyroidectomy can be safely performed also in patients with discordant localization studies with a high cure rate; in these cases, however, the use of intra-operative PTH is absolutely necessary. We suggest the need for referral of these patients to high-volume medical centers for thyroid and parathyroid surgery.

Retrospective evaluation of the pre- and postoperative factors influencing the sensitivity of localization studies in primary hyperparathyroidism.

INTRODUCTION: Over the last decades, mini-invasive surgery has become increasingly common for treatment of primary hyperparathyroidism; such approach requires preoperative localization of a suspected parathyroid adenoma. Neck ultrasound (US) and technetium-99 m sestamibi (MIBI) scan are the main imaging studies used for this purpose. The aim of the present study is to evaluate what pre- and post-operative factors may alter the reliability of localization studies. METHODS: A retrospective analysis on 212 patients with preoperative diagnosis of primary hyperparathyroidism was conducted. Data collected included demographic data, preoperative workup, operative findings and follow-up. Univariate logistic regression was performed on pre- and postoperative variables. RESULTS: US sensitivity was 62.4% and MIBI sensitivity 78.9%. Cure rate after parathyroidectomy was 98.1%. Univariate logistic regression demonstrated that US sensitivity was impaired by lower levels of serum calcium (p < 0.0001), multi-gland disease (p = 0.011) and co-existence of thyroid disease (p = 0.001); MIBI sensitivity was impaired by lower levels of serum calcium (p = 0.001) and multi-gland disease (p < 0,0001). CONCLUSIONS: Mild hypercalcaemia, multi-gland disease and co-existing thyroid disease are the main factors affecting sensitivity of preoperative imaging studies. In such patients a mini-invasive approach is possible but the use of intraoperative PTH monitoring is mandatory to reduce the risk of unsuccessful surgery.

Controversies in the management of parathyroid carcinoma: A case series and review of the literature.

Parathyroid carcinoma is a rare malignancy representing less than 1% of primary hyperparathyroidism cases. Its management is controversial due to lack of large-scale, multicentric studies. We report 8 new cases of parathyroid carcinoma and review the literature. Preoperative diagnosis of carcinoma was possible in 2 (25%) cases. Unclear surgical margins were present in 5 (62.5%) patients; 4 of them underwent subsequent re-exploration and ipsilateral hemithyroidectomy, in one case associated to central lymph node dissection. Recurrent disease is reported in 2 (25%) patients. Considering the high incidence of local recurrence in case of unclear surgical margins, a re-exploration with ipsilateral hemithyroidectomy is indicated in these patients. A neck dissection should be performed only in case of clinically involved lymph nodes, avoiding prophylactic lymphectomy. An aggressive approach is indicated in case of local or distant recurrence to reduce hypercalcemia.

Interpretation of intraoperative recurrent laryngeal nerve monitoring signals: The importance of a correct standardization.

INTRODUCTION: Despite the increasingly broad use of intraoperative neuromonitoring, review of the literature and clinical experience confirms there is little uniformity in application of and results across different centers. The aim of this study was to evaluate the ability of intraoperative neuromonitoring with a standardized evaluation of the signals to predict the postoperative functional outcome and its role in reducing the postoperative recurrent nerve palsy rates. METHODS: 2365 consecutive patients underwent thyroidectomy by a single surgical team: in 1356 patients (group A) with intraoperative neuromonitoring, in 1009 (Group B) without it. RESULTS: In group A a loss of signal was observed in 37 cases: we had 29 true positive cases, 1317 true negative, 8 false positive, and 2 false negative. Accuracy was 99.26%, positive predictive value 78.38%, negative predictive value 99.85%, sensitivity 93.55%, and specificity 99.4%. 29 unilateral nerve paralysis were observed (2.13%), 23 (1.69%) transient and 6 (0.44%) permanent. In group B 26 unilateral paralysis were observed (2.57%), 20 (1.98%) transient and 6 permanent (0.59%) Differences were not statistically significant. CONCLUSIONS: Intraoperative neuromonitoring is highly predictive of the postoperative nerve function. We obtained a very high sensitivity and negative predictive value, but also a good specificity and positive predictive value. For these reasons, in selected patients with loss of signal, the surgical strategy can be reconsidered. On the other hand, this study failed to demonstrate a statistically significant decrease in the nerve paralysis rate. Further studies are needed to better evaluate the real benefit of this technique.

Adrenal incidentalomas and subclinical Cushing syndrome: indications to surgery and results in a series of 26 laparoscopic adrenalectomies.

BACKGROUND: Casual detection of an adrenal mass, the so called incidentaloma (AI) requires an in-depth analysis of imaging phenotype together with hormonal investigation, in order to evaluate both its potential malignancy and the occurrence of a preclinical condition of hypercortisolism (Subclinical Cushing Syndrome, SCS). Aim of the present work is to evaluate surgical indications and results of surgery in patients harbouring an AI with inapparent hypercortisolism. METHODS: The study has been carried on in a series of 26 Laparoscopic Adrenalectomies (LA) performed from January 2009 and January 2015. Indications to surgery included AI (11 cases), Cushing's syndrome (7 cases), suspected metastases (5 cases) and Conn's disease (3 cases). Six patients with AI had a SCS associated with variable forms of a metabolic syndrome: they were evaluated in detail analysing cortisol secretion and values of Arterial Hypertension, Diabetes Mellitus and BMI before and after surgery. RESULTS: As far as SCS is concerned, LA was completed in 5 patients (one case converted). Pathology revealed 5 adenomas and one nodular hyperplasia. Four cases required oral cortisone administration at the discharge. At a mean follow- up of 33 months cortisol secretion returned to normal range in all patients; an improvement of metabolic condition was observed in 60, 25, and 50 per cent of hypertensive, diabetic and obese patients respectively. CONCLUSION: Indications to LA in case of AI and SCS is strongly supported by the presence of an associated metabolic syndrome. In spite of a limited number, our experience confirms the favourable results of surgery in such patients. KEY WORDS: Adrenal incidentaloma, Laparoscopic adrenalectomies, Subclinical Cushing syndrome.

The use of a biologic topical haemostatic agent (TachoSil(®)) for the prevention of postoperative bleeding in patients on antithrombotic therapy undergoing thyroid surgery: A randomised controlled pilot trial.

INTRODUCTION: Anticoagulants and antiplatelet agents are well-known risk factors for post-operative bleeding. The aim of this prospective, randomized pilot study was to evaluate the effectiveness of a topical haemostatic agent, namely TachoSil, for the prevention of postoperative bleeding in patients on antithrombotic therapy undergoing thyroidectomy. Perioperative management and some distinctive aspects of cervical haematomas were also discussed. METHODS: Between January 2012 and May 2014, all patients taking vitamin K antagonists (VKAs) or acetyl salicylic acid (ASA) scheduled for total thyroidectomy were enrolled and randomly allocated to group 1 (standard haemostasis) and group 2 (standard haemostasis + TachoSil). Antithrombotic drugs were always suspended prior to surgery and, when indicated, replaced by bridging anticoagulation with low-molecular-weight heparin. The primary endpoint was the incidence of postoperative cervical haematomas. RESULTS: A total of 70 patients were included in the study, representing 8.5% (70/820) of all patients who underwent thyroidectomies in the same period. The overall rate of post-operative cervical haematoma was 7.1% (5/70) and reached 14.8% (4/27) in patients on VKA therapy. All but one occurred more than 24 h after surgery (32nd hour, 8th, 10th, and 13th days). Group 1 (37 patients) and group 2 (33 patients) were well-matched according to clinical and demographic features. Postoperative haematoma was observed in 2/37 patients (5.4%) recruited in the Group 1 and 3/33 patients (9.1%) recruited in the Group 2 (P = 0.661). CONCLUSIONS: Patients taking antithrombotic drugs represent a major problem in thyroid surgery. The incidence of bleeding after thyroidectomy is significantly high and the use of TachoSil do not seem effective in preventing its occurrence. However, larger multicenter study is needed to confirm these results.

Intraoperative neuromonitoring in thyroid surgery: a point prevalence survey on utilization, management, and documentation in Italy.

The frequency of neuromonitoring during thyroid surgery is underreported in Italy. The present survey depicts and describes the patterns of use, management, documentation for IONM devices of IONM during thyroid surgery by surgeons in Italy. A point prevalence survey was undertaken. Source data were mixed from Italian surgeons attending the 2014 International Neuromonitoring Study Group (INMSG) meeting, four IONM manufacturers available in Italy and surgical units were identified from Company sales data. Qualitative and quantitative data were used to analyze. Questions probed IONM prevalence, surgeon background, hospital geographic practice locations, type of hospital, rationale for IONM use, sources of initial capital investment for IONM acquisition, type of equipment, use of continuous IONM, monitoring management, use of distinctive standards, and IONM documentation. IONM is currently delivered through 48 units in Italy. In 2013, the distribution of IONM by specialties included: general (50 %), ENT (46 %), and thoracic surgery (4 %). Overall, 12.853 IONM procedures were performed in the period from 2006 to 2013: 253 were performed in 2007 and about 5,100 in 2013. Distribution according to the type of hospital is: public 48 %, academic setting 37 %, and private maintenance 15 %. The use category of high volume thyroid hospitals represented 33 %. Initial capital investment for the acquisition of the monitoring equipment was 67 % public and 33 % with charitable/private funding. Audio plus graphic and EMG electrodes surface endotracheal tube-based monitoring systems accounted for the majority. Continuous IONM was introduced in 5 Academic Centers. Overall motivations expressed are legal (30 %), RLN confirmation (20 %), RLN identification (20 %), prognosis (10 %), helpful in difficult cases (10 %), decrease surgical time (5 %), and educational (5 %). The survey revealed that participants had few experience with the standardized approach of IONM technique (28 %). General IONM information to patients and/or subsequent specific IONM informed consent was initiated in 8 % of centers. EMG determinations were included in medical chart in 20 %. There were no significant associations found between all parameters considered. The present study describes an increased utilization of IONM in Italy. We highlighted areas for improvement in the management and documentation of IONM.

Differentiated thyroid cancer in the elderly: our experience.

INTRODUCTION: The objective of this retrospective study was to investigate clinical and pathologic characteristics of differentiated thyroid cancer in elderly patients and to evaluate the results of surgical treatment in this age group. METHODS: The clinical records of patients who underwent total thyroidectomy between 2002 and 2012 with histopathological diagnosis of differentiated thyroid cancer were analyzed. Patients were divided into two groups: those 65 years old or older were included in group A (101), those younger in group B (354). RESULTS: The mean surgical time was 100.9 ± 30.5 min in group A and 100.7 ± 27.6 in B. Postoperative stay was significantly longer in group A (2.8 ± 1.5 days vs 2.4 ± 0.7; p < 0.01). Classic papillary carcinoma was more frequent in group B, whereas follicular variant of papillary carcinoma and tall cell carcinoma in A. In group B node metastases were nearly twice. In Group A transient hypoparathyroidism occurred in 25 patients (24.8%), permanent hypoparathyroidism in 4 (4%), hematoma in 6 (5.9%), recurrent nerve palsy in 2 (2%), and wound infection in 2 (2%). In group B transient and permanent hypoparathyroidism occurred in 48 and 7 patients respectively (13.6% and 2%), hematoma in 4 (1.1%), recurrent nerve palsy in 5 (1.4%), and wound infection in 1 (0.3%). CONCLUSIONS: Differentiated thyroid carcinoma is more aggressive in elderly patients for biological causes connected to age and to histotype but also for the diagnostic delay. Thyroid surgery in elderly patients is safe when the procedure is carried out by experienced staff. Total thyroidectomy is the surgical operation of choice.

Identification alone versus intraoperative neuromonitoring of the recurrent laryngeal nerve during thyroid surgery: experience of 2034 consecutive patients.

BACKGROUND: The aim of this study was to evaluate the ability of intraoperative neuromonitoring in reducing the postoperative recurrent laryngeal nerve palsy rate by a comparison between patients submitted to thyroidectomy with intraoperative neuromonitoring and with routine identification alone. METHODS: Between June 2007 and December 2012, 2034 consecutive patients underwent thyroidectomy by a single surgical team. We compared patients who have had neuromonitoring and patients who have undergone surgery with nerve visualization alone. Patients in which neuromonitoring was not utilized (Group A) were 993, patients in which was utilized (group B) were 1041. RESULTS: In group A 28 recurrent laryngeal nerve injuries were observed (2.82%), 21 (2.11%) transient and 7 (0.7%) permanent. In group B 23 recurrent laryngeal nerve injuries were observed (2.21%), in 17 cases (1.63%) transient and in 6 (0.58%) permanent. Differences were not statistically significative. CONCLUSIONS: Visual nerve identification remains the gold standard of recurrent laryngeal nerve management in thyroid surgery. Neuromonitoring helps to identify the nerve, in particular in difficult cases, but it did not decrease nerve injuries compared with visualization alone. Future studies are warranted to evaluate the benefit of intraoperative neuromonitoring in thyroidectomy, especially in conditions in which the recurrent nerve is at high risk of injury.

Total thyroidectomy without prophylactic central neck dissection in clinically node-negative papillary thyroid cancer: is it an adequate treatment?

BACKGROUND: Cervical lymph node metastases in papillary thyroid cancer are common. Although central neck dissection is indicated in clinically nodal-positive disease, it remains controversial in patients with no clinical evidence of nodal metastasis. The aim of this retrospective study was to determine the outcomes of clinically lymph node-negative patients with papillary thyroid cancer who underwent total thyroidectomy without a central neck dissection, in order to determine the rates of recurrence and reoperation in these patients compared with a group of patients submitted to total thyroidectomy with central neck dissection. METHODS: Two-hundred and eighty-five patients undergoing total thyroidectomy with preoperative diagnosis of papillary thyroid cancer, in the absence of suspicious nodes, were divided in two groups: those who underwent a thyroidectomy only (group A; n=220) and those who also received a central neck dissection (group B; n=65). RESULTS: Six cases (2.1%) of nodal recurrence were observed: 4 in group A and 2 in group B. Tumor histology was associated with risk of recurrence: Hürthle cell-variant and tall cell-variant carcinomas were associated with a high risk of recurrence. Multifocality and extrathyroidal invasion also presented a higher risk, while smaller tumors were at lower risk. CONCLUSIONS: The role of prophylactic central lymph node dissection in the management of papillary thyroid cancer remains controversial. Total thyroidectomy appears to be an adequate treatment for clinically node-negative papillary thyroid cancer. Prophylactic central neck dissection could be considered for the more appropriate selection of patients for radioiodine treatment and should be reserved for high-risk patients only. No clinical or pathological factors are able to predict with any certainty the presence of nodal metastasis. In our experience, tumor size, some histological types, multifocality, and locoregional infiltration are related to an increased risk of recurrence. The potential use of molecular markers will hopefully offer a further strategy to stratify the risk of recurrence in patients with papillary thyroid cancer and allow a more tailored approach to offer prophylactic central neck dissection to patients with the greatest benefit. Multi-institutional larger studies with longer follow-up periods are necessary to draw definitive conclusions.

Role of intraoperative neuromonitoring of recurrent laryngeal nerves in the outcomes of surgery for thyroid cancer.

INTRODUCTION: The aim of this retrospective study was to evaluate the ability of intraoperative neuromonitoring to predict the postoperative functional outcome and its role in reducing the postoperative recurrent laryngeal nerve palsy rate during thyroidectomy for thyroid malignancy. METHODS: Between June 2007 and March 2013, 656 consecutive patients with thyroid cancer underwent thyroidectomy by a single surgical team. We compared 357 patients who have had neuromonitoring (Group A) to 299 patients who have undergone surgery with nerve visualization alone (group B). RESULTS: In group A 7 recurrent laryngeal nerve paralysis were observed (1.96%), 6 (1.68%) transient and 1 (0.28%) permanent; a bilateral recurrent laryngeal palsy was observed in 1 of the 7 cases (0.28%). In group B 6 recurrent laryngeal nerve paralysis were observed (2.01%), 5 (2.01%) transient and 1 permanent (0.33%); bilateral palsy was observed in 1 of the 6 cases (0.33%). Differences were not statistically significative. CONCLUSIONS: Routine visual nerve identification remains the gold standard of recurrent laryngeal nerve management in surgery for thyroid cancer. Intraoperative neuromonitoring is safe, effective, reliable, and easy to perform in excluding postoperative recurrent laryngeal palsy. It helps to identify the nerve in thyroid cancer, but it did not decrease the injuries compared with visualization alone in this study; however, its use can change the operative strategy in order to prevent the risk of bilateral damage in case of signal loss. Future studies are needed to evaluate the benefit of intraoperative neuromonitoring in thyroidectomy for thyroid cancer.

Follicular nodules (Thy3) of the thyroid: is total thyroidectomy the best option?

BACKGROUND: Identification of the best management strategy for nodules with Thy3 cytology presents particular problems for clinicians. This study investigates the ability of clinical, cytological and sonographic data to predict malignancy in indeterminate nodules with the scope of determining the need for total thyroidectomy in these patients. METHODS: The study population consisted of 249 cases presenting indeterminate nodules (Thy3): 198 females (79.5%) and 51 males (20.5%) with a mean age of 52.43 ± 13.68 years. All patients underwent total thyroidectomy. RESULTS: Malignancy was diagnosed in 87/249 patients (34.9%); thyroiditis co-existed in 119/249 cases (47.79%) and was associated with cancer in 40 cases (40/87; 45.98%). Of the sonographic characteristics, only echogenicity and the presence of irregular margins were identified as being statistically significant predictors of malignancy. 52/162 benign lesions (32.1%) and 54/87 malignant were hypoechoic (62.07%); irregular margins were present in 13/162 benign lesions (8.02%), and in 60/87 malignant lesions (68.97%). None of the clinical or cytological features, on the other hand, including age, gender, nodule size, the presence of microcalcifications or type 3 vascularization, were significantly associated with malignancy. CONCLUSIONS: The rate of malignancy in cytologically indeterminate lesions was high in the present study sample compared to other reported rates, and in a significant number of cases Hashimoto's thyroiditis was also detected. Thus, considering the fact that clinical and cytological features were found to be inaccurate predictors of malignancy, it is our opinion that surgery should always be recommended. Moreover, total thyroidectomy is advisable, being the most suitable procedure in cases of multiple lesions, hyperplastic nodular goiter, or thyroiditis; the high incidence of malignancy and the unreliability of intraoperative frozen section examination also support this preference for total over hemi-thyroidectomy.

Renal cell carcinoma metastasis to thyroid tumor: a case report and review of the literature.

INTRODUCTION: Metastatic neoplasms to the thyroid gland are rare in clinical practice. Clear cell renal carcinoma is the most frequent site of origin of thyroid metastases and represents 12 to 34% of all secondary thyroid tumors. Tumor-to-tumor metastases, in which a thyroid neoplasm is the recipient of a metastasis, are exceedingly rare. We report a case of clear cell renal carcinoma metastatic to a follicular adenoma. This is the tenth case of renal cell carcinoma metastasis to thyroid tumor reported in the literature. CASE PRESENTATION: A 62-year-old Caucasian woman with a history of clear cell renal carcinoma was admitted to our institution for multinodular goiter. A histological examination after total thyroidectomy revealed clear cell renal carcinoma metastasis to a thyroid follicular adenoma. CONCLUSIONS: Preoperative diagnosis of secondary thyroid neoplasm is difficult to achieve. The diagnosis of metastatic disease should be taken into account if patients have a history of clear cell renal carcinoma or if there is a multifocal growth pattern and clear cell appearance of the cytoplasm.

Differentiated thyroid cancer: indications and extent of central neck dissection--our experience.

The aim of this retrospective study was to determine the rate of metastases in the central neck compartment and examine the morbidity and rate of recurrence in patients with differentiated thyroid cancer treated with or without a central neck dissection. Two hundred and fifteen patients undergoing total thyroidectomy with preoperative diagnosis of differentiated thyroid cancer, in the absence of suspicious nodes, were divided in two groups: those who underwent a thyroidectomy only (group A; n = 169) and those who also received a central neck dissection (group B; n = 46). Five cases (2.32%) of nodal recurrence were observed: 3 in group A and 2 in group B. Tumor histology was associated with a risk of recurrence: Hürthle cell-variant and tall cell-variant carcinomas were associated with a high risk of recurrence. Multifocality and extrathyroidal invasion also presented a higher risk, while smaller tumors were at lower risk. The results of this study suggest that prophylactic central neck dissection should be reserved for high-risk patients only. A wider use of immunocytochemical and genetic markers to improve preoperative diagnosis and the development of methods for the intraoperative identification of metastatic lymph nodes will be useful in the future for the improved selection of patients for central neck dissections.