Impact of direct laryngoscopy vs. videolaryngoscopy on signal quality of recurrent laryngeal nerve monitoring in thyroid surgery: a randomised parallel group trial

In thyroid surgery, intra-operative neuromonitoring signals of the recurrent laryngeal nerve can be detected by surface electrodes on a tracheal tube positioned at the vocal fold level. The incidence of difficult tracheal intubation in patients undergoing thyroidectomy for nodular goitre ranges from 5.3% to 20.5%. The aim of this study was to compare videolaryngoscopy with conventional direct laryngoscopy as methods for proper placement of the surface electrode to prevent insufficient intra-operative nerve signal quality. In this prospective randomised trial, adult patients requiring tracheal intubation during thyroid surgery were randomly allocated to two groups of C-MAC^® (Macintosh style blade) videolaryngoscope or direct laryngoscopy using the Macintosh laryngoscope. Primary outcome was the incidence of insufficient signal electromyogram amplitude level (< 500 μV) after successful tracheal intubation. A total of 260 (130 per group) participants were analysed. An insufficient signal was more frequent with direct laryngoscopy (35/130, 27%), compared with C-MAC (12/130, 9%, p < 0.001). First-pass tracheal intubation success rate was lower with direct laryngoscopy (86/130 (66%)) compared with the C-MAC (125/130 (96%)) (p < 0.0001). Cormack and Lehane grade ≥ 3 was observed more frequently with direct laryngoscopy (16/130 (12%)), compared with the C-MAC (0/130, (0%)) (p < 0.0001). The results suggest that videolaryngoscopy has an impact on the quality of the initial intra-operative neuromonitoring signal in patients undergoing thyroid surgery, and this technique can provide optimised surface electrode positioning.

[EUROCRINE®: adrenal surgery 2015-2019- surprising initial results]

Hintergrund

Seit 2015 erfolgt in Europa mithilfe des EUROCRINE®-Registers eine systematische Dokumentation endokrin-chirurgischer Operationen. Ziel dieser ersten Auswertung war eine Darstellung der Versorgungsrealität für Nebenniereneingriffe in einem homogenen Versorgungsumfeld, entsprechend des deutschsprachigen Raums – bzw. des Präsenzgebiets der Chirurgischen Arbeitsgemeinschaft Endokrinologie (CAEK) der Deutschen Gesellschaft für Allgemein- und Viszeralchirurgie (DGAV) – einschließlich einer Analyse der Adhärenz zu geltenden Therapieempfehlungen.

Methodik

Es erfolgte eine deskriptive Analyse der präoperativen Diagnostik, der angewandten Operationstechniken sowie der zugrunde liegenden histologischen Entitäten der zwischen den Jahren 2015 und 2019 über EUROCRINE® in Deutschland, Österreich und der Schweiz dokumentierten Nebennierenoperationen.

Ergebnisse

In den insgesamt 21 teilnehmenden Kliniken des deutschsprachigen EUROCRINE®-Gebiets wurden 658 Operationen an Nebennieren durchgeführt. In 90 % erfolgten unilaterale, in 3 % bilaterale Adrenalektomien und in 7 % andere Resektionsverfahren. Die in 41 % der Operationen dokumentierte histologische Hauptdiagnose war das adrenokortikale Adenom. In 15 % lagen maligne Befunde zugrunde (einschließlich 6 % Nebennierenrindenkarzinome (ACC) und 8 % Nebennierenmetastasen). 23 % der Operationen erfolgten bei Phäochromozytomen. Diese wurden zu 82 % minimal-invasiv operiert, Nebennierenrindenkarzinome lediglich zu 28 % und Nebennierenmetastasen zu 66 %.

Schlussfolgerung

Überraschenderweise wurden nach Nebennierenadenomen und Phäochromozytomen an dritthäufigster Stelle Nebennierenmetastasen unterschiedlicher Primärtumoren reseziert. 28 % der ACC waren für minimal-invasive Techniken vorgesehen, wobei 20 % dieser Fälle eine Konversion zur offenen Operation erforderten. Die aktuelle Analyse deckte Diskrepanzen zwischen Versorgungsrealität und Leitlinienempfehlungen auf, aus denen sich zahlreiche Fragestellungen ergeben, welche nun in ein überarbeitetes EUROCRINE®-Modul zur Dokumentation von Nebennierenoperationen einfließen werden.

Targeted use of intraoperative frozen-section analysis lowers the frequency of completion thyroidectomy

BACKGROUND

The impact of intraoperative frozen section (iFS) analysis on the frequency of completion thyroidectomy for the management of thyroid carcinoma is controversial. Although specialized endocrine centres have published their respective results, there are insufficient data from primary and secondary healthcare levels. The aim of this study was to analyse the utility of iFS analysis.

METHODS

In the Prospective Evaluation Study Thyroid Surgery (PETS) 2 study, 22 011 operations for benign and malignant thyroid disease were registered prospectively in 68 European hospitals from 1 July 2010 to 31 December 2012. Group 1 consisted of 569 patients from University Medical Centre (UMC) Mainz, and group 2 comprised 21 442 patients from other PETS 2 participating hospitals. UMC Mainz exercised targeted but liberal use of iFS analysis for suspected malignant nodules. iFS analysis was compared with standard histological examination regarding the correct distinction between benign and malignant disease. The percentage of completion thyroidectomies was assessed for the participating hospitals.

RESULTS

iFS analysis was performed in 35.70 per cent of patients in group 1 versus 21.80 per cent of those in group 2 (risk ratio (RR) 1.6, 95 per cent c.i. 1.5 to 1.8; P < 0.001). Sensitivity of iFS analysis was 75.0 per cent in group 1 versus 63.50 per cent in group 2 (RR 1.2, 1.2 to 1.3; P = 0.040). Completion surgery was necessary in 8.10 per cent of patients in group 1 versus 20.8 per cent of those in group 2 (RR 0.4, 0.2 to 0.7; P = 0.001).

CONCLUSION

iFS analysis is a useful tool in determining the appropriate surgical management of thyroid disease. Targeted use of iFS was associated with a significantly higher sensitivity for the detection of malignancy, and with a significantly reduced necessity for completion surgery.

Prognostic Assessment of Non-functioning Neuroendocrine Pancreatic Neoplasms as a Basis for Risk-Adapted Resection Strategies

BACKGROUND

In contrast to exocrine pancreatic carcinomas, prognosis and treatment of pancreatic neuroendocrine neoplasms (PNEN) are significantly different. The variable growth pattern and associated clinical situation of functioning and non-functioning PNEN demand an individualized surgical approach. However, due to the scarce evidence associated with the rare disease, guidelines lack detailed recommendations for indication and for the required extent of surgical resection.

METHODS

In a retrospective single-center study from 1990 to 2018, 239 patients with PNEN were identified. Clinical data were collected in the MaDoc database of the University Medical Center Mainz. A total of 155 non-functional PNEN were selected for further analysis.

RESULTS

According to the classification of NET by the WHO in 2017, 28.8% (n = 40) of the tumors were G1, 61.9% (n = 86) G2, and 9.4% (n = 13) G3. In 73 patients, hepatic metastases were present. Sixty patients had lymph node metastasis. An R0 resection was achieved in 98 cases, an R1 situation in 10 cases. Five times, a tumor debulking was carried out (R2) and 5 times the operation was aborted without any resection because of the advanced tumor stage. A relapse occurred in 29 patients. Different prognostic factors (grade, tumor size, age) were analyzed. Grade-dependent 10-year overall survival rates were 79.5% (grade 1) and 60.1% (grade 2), respectively. The survival rate of grade 3 patients was limited to 66.7% after 13 months.

CONCLUSION

In our study, patients with non-functioning PNEN had a longer overall survival after successful R0 resection. The risk analysis confirmed a Ki-67 cutoff value of 5%, which divided a high- and low-risk group. Patients with a PNEC G3 (Ki-67 index > 50%) had a very poor prognosis.

Effect of intraoperative nerve monitoring on postoperative vocal cord palsy rates after thyroidectomy: European multicentre registry-based study

Background

Intraoperative nerve monitoring (IONM) of the recurrent laryngeal nerve (RLN) predicts the risk of vocal cord palsy (VCP). IONM can be used to adapt the surgical strategy in order to prevent bilateral VCP and associated morbidity. Controversial results have been reported in the literature for the effect of IONM on rates of VCP, and large multicentre studies are required for elucidation.

Methods

Patients undergoing first‐time thyroidectomy for benign thyroid disease between May 2015 and January 2019, documented prospectively in the European registry EUROCRINE®, were included in a cohort study. The influence of IONM and other factors on the development of postoperative VCP was analysed using multivariable regression analysis.

Results

Of 4598 operations from 82 hospitals, 3542 (77·0 per cent) were performed in female patients. IONM was used in 4182 (91·0 per cent) of 4598 operations, independent of hospital volume. Postoperative VCP was diagnosed in 50 (1·1 per cent) of the 4598 patients. The use of IONM was associated with a lower risk of postoperative VCP in multivariable analysis (odds ratio (OR) 0·34, 95 per cent c.i. 0·16 to 0·73). Damage to the RLN noted during surgery (OR 24·77, 12·91 to 48·07) and thyroiditis (OR 2·03, 1·10 to 3·76) were associated with an increased risk of VCP. Higher hospital volume correlated with a lower rate of VCP (OR 0·05, 0·01 to 0·13).

Conclusion

Use of IONM was associated with a low rate of postoperative VCP.

Correction to: Prognostic Assessment of Non-functioning Neuroendocrine Pancreatic Neoplasms as a Basis for Risk-Adapted Resection Strategies

This article contains parts of the doctoral thesis of F. Meyer.

[Individualization of the surgical procedure in response to overdiagnosis and overtreatment in differentiated thyroid carcinomas]

BACKGROUND

Advances in diagnostic methods have led to an early detection of thyroid nodules with debatable malignant potential in numerous cases. This can result in a potential overtreatment of thyroid lesions with very good prognosis.

OBJECTIVES

To avoid surgical overtreatment, an individualized, risk-adapted management is required that respects the different tumor biology of the underlying histological entities.

METHODS

The current guidelines of the leading professional societies, the American Thyroid Association (ATA) and the German Association of Endocrine Surgeons (CAEK), were compared and critically studied, to describe risk-adapted, more conservative treatment options for certain types of thyroid neoplasms according to the 2017 WHO definition.

RESULTS

The German CAEK recommends thyroidectomy as a routine operation in the case of thyroid carcinoma. Exceptions are papillary thyroid microcarcinoma and minimally invasive follicular thyroid carcinoma, which can be treated by lobectomy. The ATA proposes an "active surveillance" for papillary thyroid microcarcinoma and lobectomy in cases of differentiated thyroid carcinoma <4 cm in diameter in the absence of clearly predefined risk factors.

CONCLUSIONS

The pre- or intraoperative pathological diagnosis of the underlying tumor entity is the key point, which allows for an adaption of the resection strategy for thyroid malignancy. Depending on the type of carcinoma, the current guidelines of international expert societies allow for parenchyma-sparing operations and, according to the ATA, even an "active surveillance."