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The aim of this study was to develop evidence-based recommendations for determining the surgical extent in patients with locally invasive differentiated thyroid cancer (DTC). Locally invasive DTC with gross extrathyroidal extension invading surrounding anatomical structures may lead to several functional deficits and poor oncological outcomes. At present, the optimal extent of surgery in locally invasive DTC remains a matter of debate, and there are no adequate guidelines. On October 8, 2021, four experts searched the PubMed, Embase, and Cochrane Library databases; the identified papers were reviewed by 39 experts in thyroid and head and neck surgery. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the quality of evidence, and to develop and report recommendations. The strength of a recommendation reflects the confidence of a guideline panel that the desirable effects of an intervention outweigh any undesirable effects, across all patients for whom the recommendation is applicable. After completing the draft guidelines, Delphi questionnaires were completed by members of the Korean Society of Head and Neck Surgery. Twenty-seven evidence-based recommendations were made for several factors, including the preoperative workup; surgical extent of thyroidectomy; surgery for cancer invading the strap muscles, recurrent laryngeal nerve, laryngeal framework, trachea, or esophagus; and surgery for patients with central and lateral cervical lymph node involvement. Evidence-based guidelines were devised to help clinicians make safer and more efficient clinical decisions for the optimal surgical treatment of patients with locally invasive DTC.
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Clinical research including human participants should be based on truth, demonstrate scientific integrity, and follow ethical standards and guidelines to protect study participants. The publication of clinical research should be transparent and adhere to strict criteria for authorship. A thorough understanding and knowledge of ethical issues will limit investigator misconduct in clinical research and publication. In this article, basic ethical issues in clinical research and publication are reviewed and summarized based on recent guidelines.
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Background and Objectives@#Variable types of electrodes for intraoperative neuromonitoring (IONM) during thyroid surgery have been introduced to make up for the shortcomings of conventional endotracheal electromyogram tube. In this study, we sought to evaluate the efficacy of transcutaneous adhesive skin electrodes for IONM of recurrent laryngeal nerve (RLN) during thyroidectomy.Subjects and Method A total 97 nerves at risk of 80 patients were enrolled in this study. Two disposable adhesive skin electrodes were attached at both upper margins of thyroid cartilage. Using NIM 3.0 system (Medtronic), we recorded the amplitude and latency of signals of vagus nerve and RLN following the standard procedure of IONM. Clinicopathologic factors as well as the preoperative and postoperative vocal cord functions of the patients were analyzed. @*Results@#IONM was successful in all nerves at risk without any false loss of signals. There were no complications nor any significant time delay due to adhesive skin electrodes. The mean amplitudes from the vagus nerve (V1) and RLN (R1) were 230.64 µV and 293.48 µV, respectively. Two nerves at risk showed loss of signal and the two patients showed postoperative temporary vocal cord paralysis. The amplitude of signals from the vagus nerve (V1, V2) was significantly higher in the lower body mass index (BMI) group compared to that of the higher BMI group. @*Conclusion@#IONM using transcutaneous skin electrodes may be considered as an alternative technique for IONM during thyroid surgery.
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Efficiency of intraoperative neuromonitoring (IONM) for recurrent laryngeal nerve (RLN) during thyroid or parathyroid surgery has been well established. Electromyogram (EMG) tube has been utilized as a standard method of IONM for RLN. However, limitations of EMG tube including false positive signals due to malposition of the tube and relatively high cost have been issued. Recently, there have been several alternative methods using variable types of skin electrodes to overcome the limitations of conventional EMG tube. These recent methods using skin electrodes will be reviewed in this article.
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Background/Objectives@#Extracapsular dissection has the advantage of reducing complications by minimizing tissue loss of the parotid without intentionally exposing the facial nerve in patients with benign parotid tumor. However, there has been controversy over the surgical results. Thus, the surgical outcomes of extracapsular dissection for benign parotid tumor was compared to those of superficial parotidectomy.Materials & Methods: A retrospective chart review was conducted with 132 patients who received surgery for benign parotid tumor in our center from January 2014 to December 2018 retrospectively. @*Results@#A total of 132 people were enrolled, with 62 people receiving extracapsular dissection, 38 people receiving partial superficial parotidectomy and 32 people receiving superficial parotidectomy. No significant difference was found between the three groups regarding complications such as facial nerve palsy, Frey's syndrome, or first bite syndrome. Operation time and hospital stay was significantly short in extracapsular dissection group. @*Conclusion@#For well-selected cases, extracapsular dissection can be considered as an option for surgery of benign parotid tumor.
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Laryngeal lymphoepithelial carcinoma (LEC) is a rare tumor with only 34 cases in the published literature. Epidemiologically, laryngeal LEC is extremely rare in Asian. Originally, LEC is a common type of carcinoma in nasopharynx. Laryngeal LEC resembles nasopharyngeal LEC, except that most cases of laryngeal LEC are not associated with Epstein-Barr virus. We present a case of laryngeal LEC which developed at the left false cord extending to true vocal cord, para-glottic space and pre-epiglottic space. Total laryngectomy with bilateral neck dissection was performed. LEC was reported as biopsy confirmation result. The patient underwent postoperative radiotherapy and showed no evidence of recurrence during follow-up period of 42 months. In consideration that LEC in larynx have not been reported in South Korea yet, we introduce the clinical features and treatment outcomes of laryngeal LEC with literature review.
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Laryngeal lymphoepithelial carcinoma (LEC) is a rare tumor with only 34 cases in the published literature. Epidemiologically, laryngeal LEC is extremely rare in Asian. Originally, LEC is a common type of carcinoma in nasopharynx. Laryngeal LEC resembles nasopharyngeal LEC, except that most cases of laryngeal LEC are not associated with Epstein-Barr virus. We present a case of laryngeal LEC which developed at the left false cord extending to true vocal cord, para-glottic space and pre-epiglottic space. Total laryngectomy with bilateral neck dissection was performed. LEC was reported as biopsy confirmation result. The patient underwent postoperative radiotherapy and showed no evidence of recurrence during follow-up period of 42 months. In consideration that LEC in larynx have not been reported in South Korea yet, we introduce the clinical features and treatment outcomes of laryngeal LEC with literature review.
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Background and Objectives@#Surgical resection is the basic treatment for benign laryngeal tumors and transoral laser microsurgery (TLM) has been used effectively. Transoral videolaryngoscopic surgery (TOVS) is another method of surgical resection that has been introduced. However, there have not been any studies related to the usefulness of TOVS in benign laryngeal tumors. The purpose of this study was to compare the efficacy and surgical outcomes of TLM and TOVS.Subjects and Method A retrospective chart review of 85 patients were conducted. This review included two groups (TLM group, n=44 versus TOVS group, n=41) of patients who underwent transoral surgery for benign laryngeal tumors. Clinicopathologic factors of the patients and surgical outcomes such as the operation time, amount of intraoperative bleeding, hospital stay, and complications were compared between two groups. @*Results@#There were no significant differences between two groups regarding the clinicopathologic factors and surgical outcomes. The TOVS group presented relatively larger tumor size (p=0.067) and showed a tendency of shorter operation time (36.8±34.5 min) compared to that of TLM (45.6±27.9 min), but with no statistical significance (p=0.199). @*Conclusion@#TOVS may be considered as an alternative surgical method for benign laryngeal tumors.
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Background and Objectives@#Near-infrared (NIR) fluorescence photo imaging provides real time parathyroid anatomy enhancement. Moreover, autofluorescence enables intraoperative virtual reality parathyroid exploration of the optical characteristics of the parathyroid gland. This study was performed to demonstrate the new technique of visualizing the parathyroid gland using video-guided autofluorescence during thyroid and parathyroid surgery and to evaluate the outcomes. This is the first study that introduces the video-monitoring technique for intraoperative parathyroid mapping.Subjects and Method A total of 26 patients underwent 18 total thyroidectomies and 8 hemithyroidectomies in 2016. Fifty-six parathyroid glands were enrolled in this study. Surgery was performed by NIR video-monitoring via thyroid lateral side dissection to find the parathyroid tissues and extract the thyroid glands. With the operation room light turned on, the parathyroid glands were identified by the video-guided autofluorescence detection technique carried out in 3 stages (P1, P2, and P3), which are imaging with surgeon’s eyes before parathyroids exposure (P1), after identification (P2), and in extracted specimen (P3). @*Results@#The parathryoid autofluorescence could be video-monitored in real time by our NIR camera system with the indoor room light turned on. Of the total 56 parathyroids, 52 were detected by fluorescence. Of these, the location of 43 glands were predicted by using the high signal in a before-exposure state and the glands were confirmed as containing parathyroid tissues [in P1, sensitivity=82.69%, positive predictive value (PPV)=100.00%]. Of the nine glands that did not show high signals in P1, seven glands visually showed fluorescence signals (in P1 and P2, sensitivity=96.15%, PPV=100.00%). One of the two glands that showed high signals in the extracted tissue was identified as parathyroid, but the other one was proved not by histologic examination by despite high intensity fluorescence signal (in P1-P3, sensitivity=100.00%, PPV=98.08%). The accuracy of video-guided parathyroid mapping in P1, P2, and P3 were 83.93%, 96.43%, and 96.43%, respectively. @*Conclusion@#This is the first study that demonstrates the parathyroid gland autofluorescence as a real-time video-monitoring technique and shows that it could be applied to real surgery. Although parathyroid autofluorescence is a phenomenon seen in the invisible wavelength, our data suggest that the operator can see the parathyroid fluorescent signal in real time on the video-monitor. This technique could help the operator to predict the gland location and preserve them safely.
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Background and Objectives@#Recurrent laryngeal nerve (RLN) palsy is a critical complication of thyroid surgery. The aim of this study was to investigate the incidence of iatrogenic temporary or permanent RLN palsy and to determine the surgeon’s experience factor for iatrogenic RLN palsy.Subjects and Method We retrospectively reviewed 3404 patients, who underwent thyroidectomy between 2010 and 2019, to identify the surgeon’s experience factor for iatrogenic RLN palsy. Information about patient demographics, surgeon factor, whether or not intraoperative neuromonitoring (IONM) were used, and the postoperative status of RLN were collected. The incidence of RLN injury was analyzed according to the surgeon experience, surgery for thyroid cancer, effect of IONM and the extent of surgery. @*Results@#A total of 4479 RLNs were at risk in 3094 thyroidectomies in this study. There were 34 (1.10%) postoperative vocal cord palsy (VCP) cases after thyroidectomy. All patients with RLN palsy showed a unilateral type. VCP was temporary in 26 (0.84%) cases and permanent in 8 (0.26%) cases. Using the nerve at risk (NAR) method, we found that there were 34 NAR palsy out of the total (4479) NAR (0.76%), 26 NAR temporary palsy (0.58%), and 8 NAR permanent palsy (0.18%). The mean recovery time after temporary VCP ranged between 2-180 days (50.6 days in average). The incidence of permanent RLN injury was higher in surgery conducted by less experienced surgeon (1.71% in less experienced vs. 0.05% in experienced surgeon, odds ratio 35.991, p<0.001). Application of IONM had no impact on incidence of iatrogenic RLN injury. @*Conclusion@#The present study demonstrated that less experienced surgeon is associated with an increased risk of iatrogenic permanent RLN palsy after thyroidectomy.
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BACKGROUND AND OBJECTIVES: The controversy over the optimal extent of thyroidectomy for papillary thyroid carcinoma (PTC) has persisted over a long time period. Particularly, there is a lack of consensus in low-risk PTC sized >1 cm and ≤2 cm. In this retrospective study, we analyzed the oncologic outcomes between hemi-thyroidectomy and total thyroidectomy in patients with low-risk PTC sized 2 cm or less.MATERIALS AND METHODS: A retrospective chart review of 1107 patients who were diagnosed as unilateral low-risk PTC with maximal tumor size 2 cm or less and initially underwent either hemi-thyroidectomy (n=550) or total thyroidectomy (n=557) was conducted. All patients underwent ipsilateral prophylactic central neck dissection. Patients had no evidence of gross extrathyroidal extension or lymph node metastasis. Clinicopathologic factors and recurrence rate were compared according to the surgical extent and factors correlated to recurrence were analyzed.RESULTS: While the total thyroidectomy group had more aggressive clinicopathologic factors such as minimal extrathyroidal extension, multifocality, and lymph node metastasis, recurrence rate was higher in the hemi-thyroidectomy group (p=0.006). However, when the contralateral lobe recurrence was excluded there was no difference in recurrence between the two groups (p=0.597). In patients with tumor sized >1 cm and ≤2 cm there was no significant difference in recurrence between the two groups (p=0.100).CONCLUSION: Total thyroidectomy may not decrease recurrence in patients with PTC presented with unilateral tumor sized >1 cm and ≤2 cm. Hemi-thyroidectomy could be considered the treatment of choice in these patients when they are presented as a low-risk group.
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Humans , Consensus , Lymph Nodes , Neck Dissection , Neoplasm Metastasis , Recurrence , Retrospective Studies , Thyroid Gland , Thyroid Neoplasms , ThyroidectomyABSTRACT
BACKGROUND AND OBJECTIVES: Blood neutrophil-to-lymphocyte ratio (NLR) has been reported to have poor prognostic impact in variable malignancies. However, studies evaluating the clinical significance of blood NLR in patient with papillary thyroid carcinoma (PTC) has been relatively rare, and the outcomes were inconsistent. In this study, we sought to analyze the clinical value of NLR in patients with PTC who had cervical lymph node metastasis. MATERIALS AND METHODS: Retrospective chart review was conducted with 174 patients with confirmed neck metastasis of PTC after initial thyroidectomy. Blood NLR was estimated by dividing the absolute number of blood neutrophil with that of lymphocyte. Statistical analysis was conducted to evaluate correlation between NLR and clinicopathologic factors, patterns of metastatic lymph nodes, and recurrence. RESULTS: Higher NLR (>1.74) was correlated to younger age of patients ( < 45 years, p=0.045) and smaller size of tumor ( < 1 cm, p=0.017). Blood NLR had no impact on patterns of lymph node metastasis or recurrence. CONCLUSION: Blood NLR may not be considered as a predictive factor for clinical aggressiveness or prognosis in patients with PTC with lymph node metastasis.
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Humans , Lymph Nodes , Lymphocytes , Neck , Neoplasm Metastasis , Neutrophils , Prognosis , Recurrence , Retrospective Studies , Thyroid Gland , Thyroid Neoplasms , ThyroidectomyABSTRACT
BACKGROUND AND OBJECTIVES: Various methods to induce tracheal stenosis in an animal model have been introduced. However, most methods use non-physiologic mechanical or chemical injury to tracheal mucosa or cartilage. In this study, we sought to develop an animal model of tracheal stenosis using a segmented endotracheal tube. MATERIALS AND METHOD: Nine New Zealand White Rabbits were included in this feasibility study. A segmented 1.5 cm LEVIN-Tube (16 French) was inserted into tracheal lumen via tracheotomy site and fixed with a nylon tape circumferentially tied around the trachea. The tube was removed transorally one week later and the tracheal lumen was observed with bronchoscopy every week. Rabbits were sacrificed two weeks after the tube removal and the trachea was evaluated with histologic image. Three rabbits underwent tracheotomy and closure only to evaluate possible impact of tracheotomy procedure to tracheal stenosis (sham surgery). RESULTS: None of the 6 rabbits showed significant complications or death during the study. No significant change of tracheal lumen was identified in 3 sham models. The mean grade of stenosis was 57.2±9.9% (range, 43-70%). Histologic image showed thickening and fibrosis of lamina propria with relatively intact tracheal cartilage framework. CONCLUSION: We developed an animal model of tracheal stenosis using a segmented endotracheal tube fixed with a nylon tape. Since this model has similar pathophysiology to prolonged endotracheal intubation, it may be used in various studies related to tracheal stenosis.
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Animals , Rabbits , Bronchoscopy , Cartilage , Constriction, Pathologic , Feasibility Studies , Fibrosis , Intubation, Intratracheal , Methods , Models, Animal , Mucous Membrane , Nylons , Trachea , Tracheal Stenosis , TracheotomyABSTRACT
Multiple calcification in the major salivary glands is very rare. Sjogren's syndrome is characterized by tissue damage due to chronic lymphocyte infiltration of exocrine glands, and the involvement of the major salivary glands is followed by typical symptoms such as multiple formation of sialolith, blockage of salivary duct, and edema of the parenchyme. When multiple calcification is found in the parenchyme of parotid gland on the computed tomography imaging, Sjogren syndrome should be considered, where the primary solution is conservative treatment and preventing recurrent inflammation.
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Edema , Exocrine Glands , Inflammation , Lymphocytes , Parotid Gland , Salivary Ducts , Salivary Gland Calculi , Salivary Glands , Sjogren's SyndromeABSTRACT
A variety of treatment methods have been proposed for parotid sialocele. These include multiple aspirations and compression dressings, reconstruction of the duct, creation of a controlled internal fistula, superficial or total parotidectomy, radiation therapy and ductal ligation, etc. Most of these procedures are invasive with variables and often with poor success rates. This paper presents an unusual incidence of iatrogenic parotid sialocele after sialendoscopy and its management by a relatively simple, safe and effective technique, which is constituted of draining saliva into the intraoral.
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Aspirations, Psychological , Bandages , Drainage , Fistula , Incidence , Ligation , SalivaABSTRACT
BACKGROUND AND OBJECTIVES: Lymph node (LN) metastasis occurs in 30-80% of patients presenting for initial treatment of papillary thyroid carcinoma (PTC). The presence of LN metastasis is an independent risk factor for recurrence, which can add significant treatment morbidity. The LN ratio (LNR) and extranodal extension (ENE) have been shown to be important prognostic factors in PTC. The purpose of this study was to assess the characteristic features of LNR and ENE. SUBJECTS AND METHOD: We undertook a retrospective study of 411 patients treated between January, 2011 and December, 2013 for central compartment node-positive PTC by thyroidectomy and central compartment neck dissection (CCND) at our institution. We compared various clinicopathologic parameters such as age, gender, tumor size, multifocality, bilaterality, local invasion, extrathyroidal extension and aggressive variants between LNR and ENE. RESULTS: The significant associated factors for high LNR (defined as higher than 0.5) in multivariate analysis were gender (p=0.001, odds ratio=2.285) and multifocality (p=0.027, odds ratio=2.092). On the other hand, the significant associated factors for ENE in multivariate analysis were primary tumor size (p=0.023, odds ratio=1.965) and local invasion (p=0.043, odds ratio=1.870). CONCLUSION: Being male, multifocality, large primary tumor size (defined as larger than 1 cm) and local invasion were revealed as associated factors for LNR and ENE. Therefore, elective CCND should be considered for patients with PTC, for whom a thorough investigation of associative factors should be made before surgery.
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Humans , Male , Carcinoma, Papillary , Hand , Lymph Nodes , Lymphatic Metastasis , Multivariate Analysis , Neck Dissection , Neoplasm Metastasis , Recurrence , Retrospective Studies , Risk Factors , Thyroid Neoplasms , ThyroidectomyABSTRACT
Considering the relatively good prognosis of papillary thyroid carcinoma, surgical treatment should be conducted with an adequate method and extent of surgery with minimal complications. The optimal indications and extent of central neck dissection in papillary thyroid carcinoma has been introduced by variable guidelines. However, there have been controversies in several aspects regarding central neck dissection (i.e., prophylactic versus therapeutic, unilateral versus bilateral), which will remain until a large prospective study is completed. Successful management of cervical lymph node metastasis in papillary thyroid carcinoma requires thorough preoperative evaluation, knowledge on adequate indications and extent of surgery and considerations on surgical anatomy. In this article, we reviewed the rationales for optimal central neck dissection in papillary thyroid carcinoma based on recent studies and presented the surgical strategy and skills based on personal experience of a single surgeon.
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Humans , Lymph Nodes , Neck Dissection , Neoplasm Metastasis , Prognosis , Thyroid NeoplasmsABSTRACT
BACKGROUND AND OBJECTIVES: Papillary thyroid microcarcinoma (PTMC) generally has a highly favorable prognosis, however reports show a 30-65% prevalence of subclinical central lymph node metastasis. Therefore, the role of elective central neck dissection in PTMC treatment remains controversial. Our study focused on preoperative features of clinically lymph node negative and intracapsular (cT1aN0) PTMC and the correlation of these features with subclinical central lymph node metastasis. MATERIALS AND METHODS: Of 584 PTC patients who underwent thyroidectomy at the Kosin University Gospel Hospital from January 2009 to July 2011, 219 patients with cT1aN0 PTMC were reviewed retrospectively. Pathologic results were reviewed and various clinicopathologic prognostic factors were investigated. RESULTS: Postoperative pathology report revealed capsular invasion of primary tumor in 77 patients (35.2%) and subclinical central lymph node metastasis in 62 patients (28.3%). Tumor of the isthmic location was an independent predictor of subclinical central lymph node metastasis by multivariate analysis while multifocality showed borderline significance. The presence of extrathyroidal extension (ETE), multifocality, and cervical lymph node metastasis were significantly related to PTMC of isthmus. Seven of the 14 subjects with PTMC of the isthmus (50%) had pretracheal lymph node metastasis showing significant correlation (p=0.001). CONCLUSION: Despite the absence of ETE and lymph node metastasis in the preoperative imaging studies, higher risk of subclinical central lymph node metastasis should be considered in PTMC with multifocality and tumor of the isthmus.
Subject(s)
Humans , Carcinoma, Papillary , Lymph Nodes , Multivariate Analysis , Neck Dissection , Neoplasm Metastasis , Pathology , Prevalence , Prognosis , Retrospective Studies , Thyroid Gland , Thyroid Neoplasms , ThyroidectomyABSTRACT
BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the treatment outcomes of medullary thyroid carcinoma (MTC) by retrospective data analysis. SUBJECTS AND METHOD: We conducted a retrospective chart review of 17 cases of pathologically proven MTC patients who were treated from 1998 to 2010 at the department of Otolaryngology-Head and Neck Surgery, Kosin University College of Medicine. RESULTS: The mean tumor size was 2.32 cm (0.5-3.4 cm). Seventy-one percent of patients were diagnosed with advanced stage (III or IV) of MTC. We performed RET genetic screening in 8 of 17 patients. Hereditary MTC was found in 3 of 17 patients (18%) and sporadic MTC was found in 14 of 17 (82%). The preoperative assessment of basal serum calcitonin (CT) level was performed in 15 of 17 patents. Eleven patients had elevated basal calcitonin levels (>13 pg/mL). After the operation for MTC, the serum CT levels were elevated in 7 patients. Overall 5-year survival rate was 94%. Normalization of serum calcitonin level was accomplished more frequently in the absence of extra thyroidal invasion (p=0.034), multifocal tumor (p=0.02). CONCLUSION: The initial treatment of MTC is total thyroidectomy with central compartment neck dissection with or without lateral neck dissection. To detect recurrence or metastasis, regular checking of serum calcitonin is necessary. A better knowledge of prognostic factors could improve the management of MTC patients.
Subject(s)
Humans , Calcitonin , Genetic Testing , Neck , Neck Dissection , Neoplasm Metastasis , Recurrence , Retrospective Studies , Survival Rate , Thyroid Gland , Thyroid Neoplasms , ThyroidectomyABSTRACT
PURPOSE: Vocal symptoms have been reported after thyroidectomy and even in the absence of injury to the recurrent laryngeal nerve or the external branch of the superior laryngeal nerve. The aim of this prospective study was to evaluate the subjective and objective voice changes in patients without laryngeal nerve injury after thyroidectomy. METHODS: The subjects had undergone total thyroidectomy for differentiated thyroid carcinoma from November 2007 to December 2008. Twenty-eight subjects (males: 8, females: 20) were selected for this study. Voice analysis was prospectively evaluated in the subjects at the time of preoperation and postoperation (10.8 months for the males and 11.7 months for the females). A subjective analysis was done using the visual analogue scale (VAS, 0: no symptom, 10: severe symptoms) and objective analyses were determined by several parameters such as the fundamental frequency (Fo), jitter, shimmer and the noise to harmonic ratio (NHR) using the multi-dimensional voice program. Maximum phonation time (MPT)was performed as an aerodynamic test. RESULTS: 3 patients (37.5%) among the males and 14 patients (70%) among the females had subjective postoperative voice change. The VAS showed a significant difference for the females (0 to 1.25±0.97, P0.05). The vocal parameters (Fo, jitter, shimmer, NHR) and MPT showed no significant changes for both the males and females (P>0.05). CONCLUSION: Subjective voice changes may occur after thyroidectomy without laryngeal nerve injury. Surgeons should take possible voice changes into consideration when informing patients before thyroidectomy.