Superiority of continuous over intermittent intraoperative nerve monitoring in preventing vocal cord palsy.

BACKGROUND: Continuous intraoperative nerve stimulation (IONM) with uninterrupted monitoring is likely better than intermittent IONM in preventing vocal cord palsy after thyroid surgery. METHODS: This was a comparative study of intermittent versus continuous IONM in patients with benign and malignant thyroid disease treated at a tertiary centre over 10 years. Early postoperative and permanent vocal cord palsy rates were estimated. Multivariable logistic regression analysis was used to quantify the contributions of clinical and histopathological variables to early postoperative and permanent vocal cord palsy. RESULTS: A total of 6029 patients were included, of whom 3139 underwent continuous and 2890 intermittent IONM. Based on nerves at risk (5208 versus 5024 nerves), continuous IONM had a 1·7-fold lower early postoperative vocal cord palsy rate than intermittent monitoring (1·5 versus 2·5 per cent). This translated into a 30-fold lower permanent vocal cord palsy rate (0·02 versus 0·6 per cent). In multivariable logistic regression analysis, continuous IONM independently reduced early postoperative vocal cord palsy 1·8-fold (odds ratio (OR) 0·56) and permanent vocal cord palsy 29·4-fold (OR 0·034) compared with intermittent IONM. One permanent vocal cord palsy per 75·0 early vocal cord palsies was observed with continuous IONM, compared with one per 4·2 after intermittent IONM. Early postoperative vocal cord palsies were 17·9-fold less likely to become permanent with continuous than intermittent IONM. CONCLUSION: Continuous IONM is superior to intermittent IONM in preventing vocal cord palsy.

Management of primary and renal hyperparathyroidism: guidelines from the German Association of Endocrine Surgeons (CAEK).

BACKGROUND AND AIMS: The purpose of this review is to provide updated recommendations for the surgical management of primary (pHPT) and renal (rHPT) hyperparathyroidism, formulating a new guideline of the German Association of Endocrine Surgeons (CAEK). METHODS: Evidence-based recommendations for the diagnosis and therapy of pHPT and rHPT were assessed by a multidisciplinary panel using PubMed for a comprehensive literature search together with a structured consensus dialogue (S2k guideline of the Association of the German Scientific Medical Societies, AWMF). RESULTS: During the last 20 years, a variety of new preoperative localization procedures, such as sestamibi-SPECT, 4D-CT, and various PET/CT procedures, were established for pHPT. High-resolution imaging, together with intraoperative parathyroid hormone (IOPTH) measurement, enabled focused or minimally invasive surgery to become the most favored surgical technique. Patients with pHPT and nonlocalizing imaging have a higher risk of multiglandular disease. Surgical therapy provides very high cure rates, with a clear relation to the surgeon's experience in parathyroid procedures. Reoperative parathyroidectomy, children with pHPT or familial forms, and parathyroid carcinoma are addressed and require special surgical expertise. A multidisciplinary team of experienced nephrologists, transplant, and endocrine surgeons should assess the diagnosis and treatment of renal HPT. CONCLUSION: Surgery is the only curative treatment for pHPT and should be considered for all patients with pHPT. For rHPT, a more selective approach is required, and parathyroidectomy is indicated only when conservative treatment options fail. In parathyroid carcinoma, the adequacy of local resection influences local disease control.

Prediction of biochemical cure in patients with medullary thyroid cancer.

BACKGROUND: The impact of number of node metastases versus metastatic lymph node ratio versus AJCC node category on biochemical cure in medullary thyroid cancer (MTC) is not well defined. METHODS: Multivariable logistic regression analysis was used to determine clinical and histopathological variables that contribute to biochemical cure in node-positive MTC. RESULTS: Some 584 of 1026 patients with MTC underwent systematic lymph node dissections for node-positive disease; 27·4 per cent (54 of 197) were biochemically cured after the initial operation and 13·5 per cent (42 of 310 patients) after repeat surgery. Cured patients had significantly less extrathyroid extension (11-14 versus 33·2-55·6 per cent), fewer lymph node metastases (median 2-4 versus 12-16), a lower metastatic lymph node ratio (median 0·05-0·08 versus 0·23-0·28), and were less likely to have AJCC pN1b disease (56-76 versus 89·9-91·6 per cent) and distant metastases (0 versus 28·4-37·1 per cent) than patients who were not cured. Biochemical cure curves advanced steadily up to 7-12 node metastases and a metastatic lymph node ratio of 0·33, eventually levelling off after 16-17 node metastases and metastatic lymph node ratios of 0·45-0·65. In logistic regression analysis, number of lymph node metastases (odds ratio (OR) 17·24 for more than 20 metastases, OR 5·28 for 11-20 metastases, OR 2·22 for 6-10 metastases), preoperative basal serum calcitonin (OR 6·24 for over 1000 pg/ml), reoperation (OR 5·34) and extrathyroid extension (OR 2·42) independently predicted failure to reach biochemical cure. CONCLUSION: Number of lymph node metastases, unlike metastatic lymph node ratio or AJCC node category, determines likelihood of biochemical cure after initial and repeat surgery for node-positive MTC.

ANTECEDENTES: El impacto del número de metástasis ganglionares versus la relación de ganglios linfáticos metastásicos (metastatic lymph node ratio, MLNR) versus el estadio ganglionar según el American Joint Committee on Cancer (AJCC) sobre la curación bioquímica en el cáncer medular de tiroides (medullary thyroid cancer, MTC) no está bien definido. MÉTODOS: Se utilizaron análisis de regresión logística multivariable y análisis estratificados de Kaplan-Meier para determinar las variables clínicas e histopatológicas que contribuyen a la curación bioquímica en el MTC con ganglios positivos. RESULTADOS: En total, 584 de 1.026 pacientes con MTC se sometieron a disecciones sistemáticas de los ganglios linfáticos en caso de enfermedad con ganglios positivos, el 27,4% (54 de 197 pacientes) de los cuales se curaron bioquímicamente después de la cirugía inicial y el 13,5% (42 de 310 pacientes) después de la reintervención quirúrgica. Los pacientes curados tuvieron una extensión extratiroidea significativamente menor (11,1-14% versus 33,2-55,6%), menos metástasis en los ganglios linfáticos (2-4 versus 12-16 metástasis), una MLNR más baja (0,05-0,08 versus 0,23-0,28), una menor frecuencia de estadio ganglionar AJCC pN1b (55,6-76 versus 89,9-91,6%) y no tenían metástasis a distancia (0% versus 28,4-37,1%), Las curvas de tiempo hasta la curación bioquímica avanzaron de manera constante hasta las metástasis de 7 a 12 ganglios y una MLNR de 0,33, y finalmente se nivelaron después de las metástasis de 16 a 17 ganglios y una MLNR de 0,45 a 0,65. En la regresión logística, el número de metástasis en los ganglios linfáticos (razón de oportunidades, odds ratio, OR 17,2 para > 20 metástasis, OR 5,3 para 11-20 metástasis y OR 2,2 para 6-10 metástasis), la calcitonina sérica basal preoperatoria (OR 6,2 para> 1000 pg/mL), la reoperación (OR 5,4) y la extensión extratiroidea (OR 2,4) predijeron de forma independiente el fracaso para alcanzar la curación bioquímica, CONCLUSIÓN: El número de metástasis en los ganglios linfáticos, a diferencia de la MLNR y del estadio ganglionar AJCC, determina la probabilidad de curación bioquímica después de la cirugía inicial y la reintervención para el MTC con ganglios positivos.

Time to calcitonin normalization after surgery for node-negative and node-positive medullary thyroid cancer.

BACKGROUND: It remains unclear when postoperative serum calcitonin levels should be measured in patients with medullary thyroid cancer (MTC) and, specifically, whether this decision should be based on the preoperative calcitonin level or nodal status. METHODS: A cohort of patients with previously untreated MTC was studied. Kaplan-Meier analyses, stratified by preoperative calcitonin level, nodal status and number of nodal metastases, were performed to determine time to calcitonin normalization after initial surgery, with statistical analysis by means of the log rank test. RESULTS: Some 213 patients with node-negative and 182 with node-positive MTC were included in the study. Postoperative calcitonin levels normalized in a mean of 3·5 versus 3·7 days respectively among patients with preoperative calcitonin levels of 10-100 pg/ml (P = 0·815); 4·8 versus 5·3 days in those with preoperative calcitonin levels of 100·1-500 pg/ml (P = 0·026); 5·3 versus 9·9 days in patients with preoperative calcitonin levels of 500·1-1000 pg/ml (P = 0·004); and 6·6 versus 57·7 days among those with preoperative calcitonin levels exceeding 1000 pg/ml (P < 0·001). Calcitonin levels normalized in a mean of 4·7 days when nodal metastasis was not present, 5·2 days in those with one to five nodal metastases, 7·0 days in patients with six to ten nodal metastases, and 57·1 days among patients with more than ten nodal metastases. Postoperative calcitonin normalization curves paralleled each other in patients with node-negative MTC, but diverged in those with node-positive disease and with more nodal metastases. CONCLUSION: Calcitonin levels typically normalize within 1 week; and within a fortnight in those with node-positive MTC and preoperative calcitonin levels of 500·1-1000 pg/ml. With node-positive MTC and preoperative calcitonin levels exceeding 1000 pg/ml, and with more than ten nodal metastases, calcitonin normalization takes longer.

Proposal for an extended pTNM classification of thyroid carcinoma : Commentary on deficits of the 8th edition of the TNM classification.

In the 8th edition of the TNM classification of thyroid carcinomas, which was introduced in 2017, carcinomas with minimal extrathyroidal extension are no longer mentioned, which might cause problems. These tumors were explicitly categorized in previous TNM classifications (5-7th editions). Studies on the prognostic relevance of minimal extrathyroidal extension have shown conflicting results. Moreover, the vast majority of these studies retrospectively analyzed only subgroups of thyroid carcinomas (e.g. differentiated thyroid carcinoma, papillary thyroid carcinoma). The proposed subcategorization of the current TNM classification (8th edition) ensures the continuity of the parameter minimal extrathyroidal extension within the TNM categorization of thyroid carcinomas and also offers the possibility to prospectively analyze in a standardized manner the potential biological relevance of minimal extrathyroidal extension in relation to tumor categories (T/pT category).

[Morphologic diagnostic criteria of noninvasive follicular neoplasia with papillary-like nuclear features (NIFTP) : A diagnostic challenge for the patient's benefit]. / Morphologische Diagnosekriterien der nichtinvasiven follikulären Neoplasie mit PTC-äquivalenten Kernmerkmalen (NIFTP) : Eine diagnostische Herausforderung zum Nutzen des Patienten.

The major goals of the introduction of the noninvasive follicular neoplasia with papillary-like nuclear features (NIFTP) are to spare patients with a biologically indolent subgroup of the follicular variant of papillary carcinoma (FV-PTC) both overtreatment and the psychologically burden of a cancer/carcinoma diagnosis. However, strict histological and molecular pathological criteria have been introduced for the diagnosis of NIFTP. NIFTP tumors may be a few millimeters in diameter, but may also measure more than 4 cm. Histologically, an encapsulated/clearly demarcated lesion with (>70%) follicular structure and the nuclear characteristics of PTC must be present as a prerequisite; invasion of capsule/vessels must be excluded as well as significant proportions (>30%) showing a solid/trabecular/insular growth pattern, psammoma bodies, tumor necrosis, an increased mitotic rate (>3/10 HPF), and/or a BRAF V600E mutation. The establishment of the NIFTP necessitated a redefinition of the diagnostic criteria of PTC and has implications on the evaluation of fine needle biopsy (FNB) of the thyroid gland. Although a prediction is difficult, the correct diagnosis of NIFTP could lead to a 10-20% reduction in thyroid carcinoma incidence.

Long-term outcome of prophylactic thyroidectomy in children carrying RET germline mutations.

BACKGROUND: A comprehensive assessment has not been undertaken of long-term outcomes in children carrying germline RET mutations and undergoing prophylactic thyroidectomy with the aim of preventing medullary thyroid cancer (MTC). METHODS: A retrospective outcome study (1994-2017) of prophylactic thyroidectomy in children, with and without central node dissection, was performed at a tertiary surgical centre. RESULTS: Some 167 children underwent prophylactic thyroidectomy, 109 without and 58 with concomitant central node dissection. In the highest-risk mutational category, MTC was found in five of six children (83 per cent) aged 3 years or less. In the high-risk category, MTC was present in six of 20 children (30 per cent) aged 3 years or less, 16 of 36 (44 per cent) aged 4-6 years, and 11 of 16 (69 per cent) aged 7-12 years (P = 0·081). In the moderate-risk category, MTC was seen in one of nine children (11 per cent) aged 3 years or less, one of 26 (4 per cent) aged 4-6 years, three of 26 (12 per cent) aged 7-12 years, and seven of 16 (44 per cent) aged 13-18 years (P = 0·006). Postoperative hypoparathyroidism was more frequent in older children (32 per cent in the oldest age group versus 3 per cent in the youngest; P = 0·002), whether or not central node dissection was carried out. Three children developed recurrent laryngeal nerve palsy; all had undergone central node dissection (P = 0·040). All complications resolved within 6 months. Postoperative normalization of calcitonin serum levels was achieved in 114 (99·1 per cent) of 115 children with raised preoperative values. No residual structural disease or recurrence was observed. CONCLUSION: Early prophylactic thyroidectomy is a viable surgical concept in experienced hands, sparing older children the postoperative morbidity associated with delayed neck surgery.

Twenty-year experience of paediatric thyroid surgery using intraoperative nerve monitoring.

BACKGROUND: There are few data on intermittent and continuous intraoperative nerve monitoring (IONM) during thyroidectomy in children. METHODS: All children aged 18 years or younger who had standard thyroid operations using intermittent or continuous IONM between January 1998 and December 2016 were included in the study. The impact of age and type of IONM on basal amplitude, latency and complications after thyroidectomy were assessed. RESULTS: A total of 504 children were included in the study. With continuous IONM, median basal amplitude and latency increased significantly with age, more on the left side (from 199 to 870 µV, and from 3·88 to 5·75 ms) than on the right (from 340 to 778 µV, and from 2·63 to 3·50 ms). Compared with intermittent IONM with needle electrode, continuous IONM with tube electrode resulted in an increase in median basal amplitude in children aged 13-18 years on both sides (from 675 to 778 µV on the right and from 450 to 870 µV on the left), and a decrease in median latency in all children older than 3 years: in children aged 4-6 years, from 4·20 to 3·00 ms on the right and from 6·10 to 4·63 ms on the left; in children aged 7-12 years, from 4·60 to 3·50 ms and from 6·00 to 5·25 ms respectively; and in children aged 13-18 years, from 4·60 to 3·50 ms and from 6·40 to 5·75 ms. Overall, wound infection, but not bleeding/haematoma or vocal fold palsy, affected younger children more: 3 per cent of children aged 3 years or less; 2 per cent of children aged 4-6 years; and 0 per cent of children aged over 6 years (P = 0·031). With continuous IONM, no wound infection, bleeding/haematoma or permanent vocal fold palsy was noted in any age group. CONCLUSION: Continuous IONM measures nerve electrophysiology more accurately than intermittent IONM during thyroidectomy in children.

Risk profile analysis and complications after surgery for autoimmune thyroid disease.

BACKGROUND: Surgical approaches to autoimmune thyroid disease are currently hampered by concerns over postoperative complications. Risk profiles and incidences of postoperative complications have not been investigated systematically, and studies with sufficient power to show valid data have not been performed. METHODS: A prospective multicentre European study was conducted between July 2010 and December 2012. Questionnaires were used to collect data prospectively on patients who had surgery for autoimmune thyroid disease and the findings were compared with those of patients undergoing surgery for multinodular goitre. Logistic regression analysis was used to evaluate risk factors for thyroid surgery-specific complications, transient and permanent recurrent laryngeal nerve (RLN) palsy and hypoparathyroidism. RESULTS: Data were available for 22 011 patients, of whom 18 955 were eligible for analysis (2488 who had surgery for autoimmune thyroid disease and 16 467 for multinodular goitre). Surgery for multinodular goitre and that for autoimmune thyroid disease did not differ significantly with regard to general complications. With regard to thyroid surgery-specific complications, the rate of temporary and permanent vocal cord palsy ranged from 2·7 to 6·7 per cent (P = 0·623) and from 0·0 to 1·4 per cent (P = 0·600) respectively, whereas the range for temporary and permanent hypoparathyroidism was 12·9 to 20·0 per cent (P < 0·001) and 0·0 to 7·0 per cent (P < 0·001) respectively. In logistic regression analysis of transient and permanent vocal cord palsy, autoimmune thyroid disease was not an independent risk factor. Autoimmune thyroid disease, extent of thyroid resection, number of identified parathyroid glands and no autotransplantation were identified as independent risk factors for both transient and permanent hypoparathyroidism. CONCLUSION: Surgery for autoimmune thyroid disease is safe in comparison with surgery for multinodular goitre in terms of general complications and RLN palsy. To avoid the increased risk of postoperative hypoparathyroidism, special attention needs to be paid to the parathyroid glands.

[Ectopic tissue of the thyroid gland and the parathyroid glands]. / Ektopes Gewebe der Schilddrüse und der Nebenschilddrüsen.

Ectopic thyroid tissue results from developmental defects of the early stages of thyroid embryogenesis, in which the median thyroid anlage descends from the floor of the mouth to its final pre-tracheal position. The most common sites of ectopic thyroid tissue are accordingly in the area of the floor of the mouth and in the course of the thyroglossal duct. Rare localizations are intrathoracic (mediastinal, cardiac, pulmonary) and sub-diaphragmatic (including the adrenals, liver, gall bladder, and gastrointestinal tract). The most important differential diagnosis of ectopic thyroid is metastasis of differentiated thyroid carcinoma.By contrast, the term parathyroidectopy is not uniformly defined. Usually, the cervical-central localizations are referred to as "positional variants" (with the exception of the maxillary sinus and high parapharyngeal), whereas the cervical-lateral localizations (carotid sheath, vagus nerve) and those below the brachiocephalic and mediastinal positions (extraligamentary, aortopulmonary window, paravagal) and other rare localizations are classified as "ectopic parathyroid tissue". Parathyroidectomy is very common (in autopsy studies in 28 to 42.8% of all humans). In the context of primary hyperparathyroidism (pHPT), there is a prevalence of 6.3 to 16% of ectopic hyperfunctional parathyroid tissue (predominantly adenomas), which play an important role in the surgical treatment of pHPT.

[Proposal for an extended pTNM classification of thyroid carcinoma : Commentary on deficits of the 8th edition of the TNM classification (German version)]. / Vorschlag zu einer erweiterten pTNM-Klassifikation der Schilddrüsenkarzinome : Kommentar zu Defiziten der 8. Auflage der TNM-Klassifikation.

In the 8th edition of the TNM classification of thyroid carcinomas, which was introduced in 2017, carcinomas with minimal extrathyroidal extension are no longer mentioned, which might cause problems. These tumors were explicitly categorized in previous TNM classifications (5-7th editions). Studies on the prognostic relevance of minimal extrathyroidal extension have shown conflicting results. Moreover, the vast majority of these studies retrospectively analyzed only subgroups of thyroid carcinomas (e.g. differentiated thyroid carcinoma, papillary thyroid carcinoma). The proposed subcategorization of the current TNM classification (8th edition) ensures the continuity of the parameter minimal extrathyroidal extension within the TNM categorization of thyroid carcinomas and also offers the possibility to prospectively analyze in a standardized manner the potential biological relevance of minimal extrathyroidal extension in relation to tumor categories (T/pT category).

Endpoints for screening thyroid cancer in the Republic of Korea: thyroid specialists' perspectives.

Cancer screening is aimed primarily at reducing deaths from the specific cancer. Thyroid-specific cancer mortality may be the most ambitious endpoint for obtaining estimates of screening effect. Numerous observations have accumulated over the years, indicating that thyroid cancer mortality endpoint has been difficult to study and is confounded by population heterogeneity, provision of randomization, and requirement of large cohorts with sufficiently long follow-up due to the excellent prognosis of the cancer. Accordingly, it may be important to reconsider how to best measure thyroid cancer screening efficacy. Recommendations against thyroid cancer screening should be based upon trials designed to evaluate its effectiveness not only in significant reduction in cancer mortality, but also of other distinct endpoints. It is desirable to evaluate derivative endpoints that can reliably predict reductions in mortality. The term "derivative" means a variable that is related to the true endpoint and is likely to be observable before the primary endpoint. Derivative endpoints may include thyroid cancer incidence, the proportion of early-stage tumors detected, more treatable stage, the identification of small tumors (to maintain in observation), decrease in the number of people who develop metastatic disease, the increased chance of lesser extent surgery, and the application of minimally invasive approaches, as well as no need for lifelong thyroid replacement therapy, a consistent follow-up, low-dose or no RAI administration and risk factor assessments where case findings should be continuous. The Korean guidelines for thyroid cancer national-level screening were published by a relevant group of multidisciplinary thyroid experts. It was concluded that the evidence is insufficient to balance the benefits and harms of thyroid cancer screening. However, the paper seems to raise the necessary investments in future research and demand a complete analysis for derivative endpoints, and offer screening participants with complete information necessary to make decisions that will provide them with the most value when a small thyroid cancer is screen-identified.

[Key Points of Intraoperative Diagnostic Measures Performed by Anaesthesiologists]. / Relevante Eckpunkte der intraoperativen anästhesiologischen Diagnostik.

The main focus of surgeons and anaesthesiologists during a surgical procedure is on safety and optimal treatment of the patient. Within the scope of interdisciplinary collaboration, the intraoperative communication between surgeons and anaesthesiologists is the basis of case-, findings- and surgery-phases-adapted patient management. The perioperative monitoring of patients and the implementation of diagnostic measures by anaesthesiologists are essential for optimal patient management. The results of the examinations may significantly determine the course of surgery. Therefore, it is important for surgeons to be familiar with the relevant intraoperative diagnostic measures.

The Transcriptional Regulation of FOXO Genes in Thyrocytes.

FOXO transcription factors are key regulators of DNA damage repair, proliferation and apoptosis in thyrocytes. Thyroid malignancies show impaired FOXO function. In this study, we investigated the transcriptional regulation of FOXO isoforms in thyroid epithelial cells. mRNA expression of FOXO isoforms (FOXO1, 3 and 4) was determined in FRTL-5 cells stimulated with different growth factors and H2O2. Furthermore, the impact of PI3K/AKT signalling on FOXO transcription was investigated in PI3K p110α mutant FRTL-5 cells and regulatory dependence of FOXO transcription on FOXO was studied in FRTL-5 cells with hFOXO3 overexpression. Finally, mRNA expression levels of FOXO isoforms were determined in human epithelial thyroid tumours. Growth factor deprivation induced transcription of FOXO1, 3 and 4, whereas insulin stimulation decreased FOXO1 and FOXO4 transcription in FRTL-5 cells. Inhibition of the PI3K/AKT cascade amplified FOXO1 and FOXO4 expression. In contrast, H2O2 and TSH did not influence FOXO transcription in thyrocytes. Overexpression of PI3K p110α inhibited FOXO3 and induced FOXO4 transcription. In human thyroid tumours, FOXO1 and FOXO3 mRNA levels were significantly downregulated in papillary thyroid carcinoma when compared to normal tissues. In contrast, follicular thyroid carcinomas showed significant upregulation of FOXO4 mRNA.In this paper, we demonstrate an influence of PI3K signalling on FOXO transcription in thyrocytes. Moreover, we show that thyroid cancers exhibit alterations in FOXO transcription besides the previously reported alterations in posttranslational FOXO3 regulation. These findings may add to the concept of targeting the PI3K pathway in advanced thyroid cancers.

Expression of ARE-binding proteins AUF1 and HuR in follicular adenoma and carcinoma of thyroid gland.

Both adenylate-uridylate rich elements binding proteins AUF1 and HuR may participate in thyroid carcinoma progression. In this study we investigated the expression of both factors on a protein level with a special focus on follicular adenoma and follicular thyroid carcinoma. By employment of immunofluorescence and western blot on 68 thyroid tissues including 7 goiter, 16 follicular adenoma (4 adenomatous hyperplasia), 19 follicular thyroid carcinomas, 13 papillary thyroid carcinomas and 14 undifferentiated thyroid carcinomas we investigated protein expression of AUF1 and HuR. In addition to previous results we demonstrated that AUF1 and HuR are significantly up-regulated in carcinoma tissues as compared with follicular adenoma or goiter tissues. Furthermore, by evaluation of AUF1 or HuR expression, or combination of both proteins on total tissue lysates, we were able to demonstrate a significant difference between follicular adenoma and follicular thyroid carcinoma. Overexpression of AUF1 and HuR is a common finding observed in thyroid malignancy. Analysis of the tissues obtained by surgical resection as demonstrated in this study is comparable to a fine needle aspiration and in combination with AUF1/HuR immuno-analysis may support the conventional immunohistological investigations. The promising results of this study were performed on relatively small collective, but justify future development of a quick thyroid diagnostic test on larger cohort of the patients, especially for thyroid samples which are inadequate for histological examinations.

Postoperative vocal fold palsy in patients undergoing thyroid surgery with continuous or intermittent nerve monitoring.

BACKGROUND: Continuous monitoring of electromyographic (EMG) amplitudes of the vocal muscles detects impending injury of the recurrent laryngeal nerve (RLN) during thyroid operations earlier than intermittent EMG monitoring. This may alert the surgeon to stop a manoeuvre causing stretching or pressure on the RLN, with better recovery of nerve function. METHODS: Patients with intact preoperative RLN function who underwent thyroid surgery for benign disease between January 2011 and September 2014 under continuous intraoperative nerve monitoring (CIONM) or intermittent intraoperative nerve monitoring (IIONM) were included in this observational study conducted at a tertiary surgical centre. For CIONM, combined EMG events indicative of imminent nerve injury were defined as an EMG amplitude decrease of 50 per cent or more and a latency increase of 10 per cent relative to baseline values. The rates of early and permanent palsy for the two groups of patients were compared. RESULTS: There were 1526 patients, 788 of whom (1314 nerves at risk) underwent thyroid surgery using CIONM and 738 (965 nerves at risk) had IIONM. With the use of CIONM, 63 (82 per cent) of 77 combined events were reversible during the operation. No permanent vocal fold palsy occurred with CIONM, whereas four unilateral permanent vocal fold palsies (0·4 per cent) were diagnosed after IIONM (P = 0·019). CONCLUSION: Operation with CIONM resulted in fewer permanent vocal fold palsies compared with IIONM after thyroid surgery in patients with benign disease.

[Intraoperative frozen sections of the thyroid gland]. / Intraoperativer Gefrierschnitt der Schilddrüse.

The goal of evaluation of intraoperative frozen sections of the thyroid gland is to achieve a definitive diagnosis which determines the subsequent surgical management as fast as possible; however, due to the specific methodological situation of thyroid frozen sections evaluation a conclusive diagnosis can be made in only some of the cases. If no conclusive histological diagnosis is possible during the operation, subsequent privileged processing of the specimen allows a final diagnosis at the latest within 48 h in almost all remaining cases. Applying this strategy, both pathologists and surgeons require a high level of communication and knowledge regarding the specific diagnostic and therapeutic peculiarities of thyroid malignancies because different surgical strategies must be employed depending on the histological tumor subtype.

[Medullary thyroid carcinoma]. / Das medulläre Schilddrüsenkarzinom.

Medullary thyroid carcinoma (MTC) is a very rare malignancy, which arises from parafollicular C cells and accounts for 3-5% of all thyroid cancers. MTC represents a neuroendocrine tumor with a biology that differs considerably from differentiated thyroid cancer. Presence of a RET proto-oncogene germline mutation indicates hereditary C cell disease in the context of multiple endocrine neoplasia type 2 and hence a special treatment algorithm is required. Cure of MTC is only possible through surgery. Calcitonin screening is advocated for early MTC diagnosis and preoperative MTC management stratification. In case of surgically incurable persistent MTC, estimation of calcitonin and CEA doubling time is crucial to assess tumor biology and is complemented by multimodal imaging to assess tumor burden. Treatment decisions in incurable MTC must be carefully balanced with treatment-related morbidity, since MTC may take an indolent course over years.

[Surgical management of renal hyperparathyroidism]. / Chirurgisches Management des renalen Hyperparathyreoidismus.

Conservative management of renal hyperparathyroidism has changed recently. Innovative substances, especially the advent of calcimimetics, have influenced the therapeutic concept. Consequently, a decline in surgical frequency for renal hyperparathyroidism has been reported. In this context it is now mandatory to evaluate the role of surgery, the surgical strategy and procedures for renal hyperparathyroidism anew. Based on a review of the literature the current position of surgical indications and care for renal hyperparathyroidism as well as possible influences of innovative medical treatment are highlighted. In summary, the timing and indications for surgery have been influenced, however, surgery still remains the only permanently effective treatment option for renal hyperparathyroidism.