Analysis of the Outcomes of Immediate Recurrent Laryngeal Nerve Reconstruction During Thyroid Surgery for Prevention of Vocal Fold Paralysis.

BACKGROUND: Recurrent laryngeal nerve (RLN) injury and the resulting paralysis is the most common and known complication of thyroid surgery. Several surgical techniques, such as medialization thyroplasty with or without arytenoid adduction and injection laryngoplasty, have been developed to treat RLN injury, but these procedures have specific limitations and complications. In this study, we present the outcomes for our patients who underwent immediate RLN reconstruction during thyroid surgery by analyzing both subjective and objective outcomes. METHODS: A retrospective study was conducted for patients who underwent total or subtotal thyroidectomy between May 2012 and March 2020. Among them, patients who underwent immediate RLN reconstruction due to unilateral RLN injury were followed for at least 12 months. The voice perceptual evaluation, acoustic analysis, voice range profile, and Voice Handicap Index (VHI) scores were obtained preoperatively, 1 month, 6 months, and 12 months after surgery. RESULTS: Among the 11 patients, 6 patients (54.5%) underwent direct anastomosis, and 5 patients (45.5%) underwent nerve grafts using ansa cervicalis and great auricular nerve. The grade and breathiness in the GRBAS (grade, roughness, breathiness, asthenia, and strain) scale and jitter item showed significant improvement at 12 months postoperatively, and although not statistically significant, the rest of the items also tended to improve. The total, functional, and physical scores on VHI improved significantly at 12 months postoperatively. Moreover, when comparing the voice analysis of the direct anastomosis group and the nerve graft group, there was no significant difference between the groups in objective and subjective results. CONCLUSION: Immediate RLN reconstruction demonstrated significant voice improvement postoperatively, and reconstructing the nerve immediately and combining follow-up treatment in the event of RLN injury will greatly help patients improve their long-term voice outcomes.

A new histopathological location of parathyroid gland with high possibility of unintended parathyroidectomy.

Background: Unintended parathyroidectomy occasionally happens despite meticulous capsular dissection and the histopathological location of removed parathyroid glands were traditionally classified as extracapsular, subcapsular, and intrathyroidal location. This study aimed to investigate the new histopathological location of parathyroid gland with high possibility of unintended parathyroidectomy that was difficult to be found with naked eye despite capsular dissection. Methods: This study investigated unintended parathyroidectomy that occurred in 743 patients who received thyroid surgery by reviewing pathology reports and slides. The histopathological location of unintentionally removed parathyroid glands was classified as intracapsule and extracapsule, and the intracapsular glands were further classified as completely buried in the thyroid parenchyme, partially buried, and subcapsular locations. Results: The incidence of unintended parathyroidectomy was 12.8%. Among the 103 unintentionally removed parathyroid glands, 74 (71.8%) were found intracapsular and 29 were extracapsular. Among the intracapsular glands, 57 (55.4%) parathyroid glands were found in difficult locations such as completely buried (40.8%) and partially buried (14.6%). Conclusions: The partially buried parathyroid gland can act as a risk factor for unintended parathyroidectomy comparable to intrathyroidal parathyroid gland despite the surgeon's best effort with meticulous capsular dissection. However, continued advances in visualizing technique such as autofluorescence imaging may lower the chance of incidentally removed partially buried parathyroid glands in the future.

Matrix metalloproteinase-7 induces E-cadherin cleavage in acid-exposed primary human pharyngeal epithelial cells via the ROS/ERK/c-Jun pathway.

Laryngopharyngeal reflux disease (LPRD) is caused by pharyngeal mucosal damage due to the reflux of gastric contents, including acid, pepsin, and bile juice. Our previous study has demonstrated that LPRD is associated with the cleavage of E-cadherin, which is facilitated by the acid-activated matrix metalloproteinase-7 (MMP-7); however, the mechanism by which the acid activates MMP-7 remains unclear. The purpose of this study was to investigate the mechanism by which MMP-7 is activated in the pharyngeal epithelial cells that are exposed to acid. The levels of reactive oxygen species (ROS) were measured in the epithelial cells exposed to acid. To investigate the signaling mechanism of ROS in the expression of MMP-7, the mechanism of action of the mitogen-activated protein kinase was examined. The expression of various signaling factors was determined, according to the presence or absence of each inhibitor in the acid-exposed pharyngeal epithelial cells. To identify changes in the cleavage of E-cadherin, the integrity of the mucosal membrane was assessed using a transepithelial permeability test. We found that acid exposure increased the levels of ROS, phosphorylated-extracellular signal-regulated kinase (p-ERK) 1/2, and phosphorylated-c-Jun (p-c-Jun) in pharyngeal epithelial cells. The ROS inhibitor reduced the expression of p-ERK and MMP-7, while the ERK inhibitor reduced the expression of p-c-Jun and MMP-7. Moreover, the c-Jun inhibitor reduced the expression of MMP-7 and blocked the degradation of E-cadherin. In addition, decrease in the levels of immunostained E-cadherin and increase in transepithelial permeability after acid exposure were collectively alleviated by the inhibitors of ROS, ERK, and c-Jun. The degradation of E-cadherin that occurs after human mucosal cells are exposed to acid appears to be caused by an increase in the expression of MMP-7 via the ROS/ERK/c-Jun pathway, which is thought to be an important mechanism associated with the development of LPRD. KEY MESSAGES: • ROS is triggered when reflux occurs. • ROS regulates the transcription factor c-Jun via the ERK pathway. • The increase in MMP-7 that induces LPRD is induced via the ROS/ERK/c-Jun pathway. • This study revealed for the first time the expression mechanism of MMP-7, which is one of the causes of LPRD.

The Utility of Gastrointestinal Endoscopic Examination Versus Positron Emission Tomography-Computed Tomography in the Detection of Second Primary Lesions in Korean Patients With Head and Neck Cancer.

OBJECTIVE: Head and neck cancer often accompany a synchronous secondary primary lesion in the digestive tract. The aim of this study was to compare detection rates between positron emission tomography-computed tomography (PET-CT) and esophagogastroduodenoscopy (G-fiber) or colonoscopy (C-fiber) in the initial staging and to analyze risk factors for premalignant, malignant, and total synchronous secondary primary lesions. METHODS: A total of 739 patients with head and neck cancer who underwent PET-CT, G-fiber, or C-fiber were analyzed retrospectively. RESULTS: Positron emission tomography-CT did not definitely detect any premalignant synchronous secondary primary lesions (0 [0%] of 739) but definitely detected 10 malignant synchronous secondary primary lesions (10 [1.35%] of 739). Esophagogastroduodenoscopy or C-fiber detected all 20 premalignant synchronous secondary primary lesions (20 [2.71%] of 739) and all 37 malignant synchronous secondary primary lesions (37 [5.00%] of 739). The patients with nasopharynx cancer tended to have premalignant synchronous secondary primary lesions (odds ratio [OR]: 3.793; 95% CI: 1.414-10.171; P = .008). Those with distant metastasis tended to have premalignant (OR: 4.743; 95% CI: 1.508-14.916; P = .009), malignant (OR: 3.803; 95% CI: 1.486-9.731; P = .005), and total synchronous secondary primary lesions (OR: 2.753; 95% CI: 1.159-6.538; P = .022). CONCLUSIONS: Premalignant or malignant synchronous secondary primary lesions that were not definitely detected by PET-CT could be found in the endoscopic examination.

Effectiveness of a combination therapy using non-ablative fractional laser and intralesional triamcinolone injection for thyroidectomy scar treatment: a prospective, randomized, blinded pilot study.

BACKGROUND: The occurrence of thyroid cancer has increased dramatically, and postoperative scars are placed at easily visible locations. Many patients show stronger desire for scar prevention. So far, numerous approaches have been discussed for the treatment of scars; this study is conducted to verify whether the early application of combined therapy contributes to minimal scar formation. METHODS: Between March 2019 and December 2019, total of 64 patients with thyroidectomy scars of a size greater than 4.5 cm located on the anterior neck were enrolled in this prospective pilot study. Subjective and objective evaluation were carried out using the Patient and Observer Scar Assessment Scale (POSAS) at one, two, and six months after operation. Results were compared between a treatment group and a non-treatment group. RESULTS: In PSAS score, the mean values of pain, itching sensation, pliability, thickness, and relief were significantly higher in the laser and steroid treatment group (p = 0.009, p = 0.000, p = 0.013, p = 0.002, and p = 0.007). The value of color of the scars showed no significant differences (p = 0.504). In OSAS score, parameter of thickness, relief, and surface area score was significantly higher score in the combination group (p = 0.029, 0.035, and 0.020), while vascularity, pigmentation, and pliability were not significantly different between two groups (p = 0.548, p = 0.983, and p = 0.128). CONCLUSION: This study demonstrates that early combination therapy contributes to scar improvement to a meaningful extent based on POSAS. We believe that the combined therapy has a synergy effect on scar management, which improves the patients' quality of life in relation to their postoperative scars.

Association between oral health and thyroid disorders: A population-based cross-sectional study.

OBJECTIVES: In this study, we aimed to determine the relationship between oral health status and thyroid dysfunction. METHODS: A population-based cross-sectional analysis using data from the Korean National Health and Nutrition Examination Survey (KNHNES) was performed. We investigated the association between oral health-related parameters and the prevalence of thyroid diseases. In addition, the relationship between oral health status and thyroid function test (TFT) results was analyzed. One-way analysis of variances or chi-square test was used for comparisons between oral health-related parameters and presence of thyroid diseases. Univariable and multivariable logistic regression analyses were conducted to evaluate the associations between participants' characteristics including oral health-related parameters and the abnormal results of TFTs. RESULTS: A total of 18,034 adults were surveyed. Histories of thyroid diseases were found to be more common in people who brushed their teeth frequently or used oral hygiene products. However, histories of periodontitis and community periodontal index (CPI) did not show significant associations with histories of thyroid diseases. Among 14,860 participants without history of thyroid disorders, people having higher CPI values demonstrated higher probabilities of abnormal TFTs (OR 1.381, 95% CI 1.241-1.537, p < .0001); however, statistical significance was not found after adjusting for the other variables. CONCLUSIONS: Our study demonstrated that good oral health-related behavior was associated with more frequent thyroid disease history. High CPI showed a significant association with TFT abnormalities; however, the significance of this association became lower when other variables such as age and sex were adjusted. Further studies will be needed to determine how the control of oral health-related conditions actually has a causal relationship with thyroid disease/dysfunction through prospective cohort studies.

Usefulness of matrix metalloproteinase-7 in saliva as a diagnostic biomarker for laryngopharyngeal reflux disease.

Several diagnostic methods are currently being used to diagnose LPRD (laryngopharyngeal reflux disease), but have the disadvantage of being invasive, subjective, or expensive. Our purpose in this study was to investigate the correlation between pepsin and MMP-7 (Matrix Metalloproteinase-7) in pharyngeal secretions of subjects according to RSI (Reflux Symptom Index) score to find out the diagnostic value of MMP-7. We recruited 173 subjects aged between 19 and 85 years who completed the RSI scale. All samples were taken after waking up, and the amount of the pepsin and MMP-7 in saliva were measured by means of an enzyme activity assay. There was a significant increase of pepsin and MMP-7 activity in the study group with an RSI score of 13 or higher. The sensitivity and specificity of MMP-7 for predicting the possibility of an RSI of 13 or more was higher than that of pepsin. When MMP-7 and pepsin were combined, this sensitivity and specificity increased. An enzyme assay of MMP-7 in saliva may be a noninvasive and easy technique for diagnosing LPRD.

Application of M1 macrophage as a live vector in delivering nanoparticles for in vivo photothermal treatment.

Introduction: To enhance photothermal treatment (PTT) efficiency, a delivery method that uses cell vector for nanoparticles (NPs) delivery has drawn attention and studied widely in recent years. Objectives: In this study, we demonstrated the feasibility of M1 activated macrophage as a live vector for delivering NPs and investigated the effect of NPs loaded M1 stimulated by Lipopolysaccharide on PTT efficiency in vivo. Methods: M1 was used as a live vector for delivering NPs and further to investigate the effect of NPs loaded M1 on PTT efficiency. Non-activated macrophage (MФ) was stimulated by lipopolysaccharide (LPS) into M1 and assessed for tumor cell phagocytic capacity towards NPs. Results: We found M1 exhibited a 20-fold higher uptake capacity of NPs per cell volume and 2.9-fold more active infiltration into the tumor site, compared with non-activated macrophage MФ. We injected M1 cells peritumorally and observed that these cells penetrated into the tumor mass within 12 h. Then, we conducted PTT using irradiation of a near-infrared laser for 1 min at 1 W/cm2. As a result, we confirmed that using M1 as an active live vector led to a more rapid reduction in tumor size within 1 day indicating that the efficacy of PTT with NPs-loaded M1 is higher than that with NPs-loaded MФ. Conclusion: Our study demonstrated the potential role of M1 as a live vector for enhancing the feasibility of PTT in cancer treatment.

Non-surgical animal model of gastroesophageal reflux disease by overeating induced in mice.

Previous animal models of gastroesophageal reflux disease (GERD) were not physiological and required a variety of surgical procedures. Therefore, the animal model developed by conditions that are similar to the pathogenesis of GERD is necessary. The aim is to establish a non-surgical animal model with GERD caused by overeating induced in mice. To induce mice to overeat, we designed dietary control protocols including repetitive fasting and feeding. The esophageal tissues were evaluated with GERD markers to prove the establishment of a GERD animal model. Mice fasted every other day (group 2) showed more pronounced overeating feature and demonstrated evident changes similar to the macroscopic and microscopic findings of GERD, the expressions of inducible nitric oxide synthase and substance P were stronger. The higher frequency of fasting and overeating could cause GERD effectively. The dietary control can make mice overeat, which elicits the change of lower esophageal mucosa similar to GERD. Thus, the overeating-induced mouse may be used as a GERD mouse model.

Current Protocol for Aesthetic Scar Management in Thyroid Surgery.

OBJECTIVES/HYPOTHESIS: We compared the scar quality when different protocols were applied, and eventually aim to find the optimal scar management protocol. STUDY DESIGN: We conducted a prospective, randomized, and blinded comparison of different scar management protocols in a single center. METHODS: We allocated 126 patients who underwent thyroidectomy via collar neck incision randomly into three groups. Patients in group A were treated with tissue adhesive only. Patients in group B were treated by means of subcuticular suturing and early scar management with a non-ablative fractional laser (NAFL) and intralesional triamcinolone injection (ILI). Patients in group C had skin closure with tissue adhesive and early scar management. At 6 months after the operation, the Patient and Observer Scar Assessment Scale (POSAS) and the width of the final scar were compared. RESULTS: Comparing the sum of PSAS, groups B and C showed significant higher satisfaction than did group A (22.81 ± 11.66 in group A, 10.9 ± 5.14 in group B, and 15.19 ± 9.98 in group C). In the sum of OSAS, group B also showed a significant difference than did groups A and C (17.74 ± 6.75 in group A, 10.26 ± 3.60 in group B, and 14.52 ± 6.48 in group C). Also, group B showed a narrower scar width than did groups A and C. CONCLUSIONS: Our finding suggests that subcuticular suturing using barbed suture material and early treatment with a combination therapy using NAFL and ILI showed a favorable aesthetic outcome for both patients and operators. Based on our algorithmic approach for thyroidectomy scar, we anticipate an optimal aesthetic outcome. LEVEL OF EVIDENCE: II Laryngoscope, 131:E2188-E2195, 2021.

Survival Benefits From Surgery for Stage IVa Head and Neck Squamous Cell Carcinoma: A Multi-institutional Analysis of 1,033 Cases.

OBJECTIVES: Head and neck squamous cell carcinomas (HNSCs) are frequently diagnosed at the locoregional advanced stage (stage IVa), but controversy remains regarding whether stage IVa HSNCs should be treated with upfront surgery or definitive chemoradiation therapy (CRT). The purpose of this study was to compare overall survival (OS) and disease-free survival (DFS) in patients with stage IVa HNSC treated primarily by surgery with curative intent with/without (neo)adjuvant treatment (surgery group) versus those treated primarily with CRT (CRT group). METHODS: We reviewed data of 1,033 patients with stage IVa HNSC treated with curative intent at 17 cancer centers between 2010 and 2016. RESULTS: Among 1,033 patients, 765 (74.1%) received upfront surgery and 268 (25.9%) received CRT. The 5-year OS and DFS rates were 64.4% and 62.0% in the surgery group and 49.5% and 45.4% in the CRT group, respectively. In multivariate analyses, OS and DFS were better in the surgery group than in the CRT group (odds ratio [OR] for death, 0.762; 95% confidence interval [CI], 0.592-0.981; OR for recurrence, 0.628; 95% CI, 0.492-0.802). In subgroup analyses, the OS and DFS of patients with oropharyngeal cancer were better in the surgery group (OR for death, 0.548; 95% CI, 0.341-0.879; OR for recurrence, 0.598; 95% CI, 0.377-0.948). In the surgery group, patients with laryngeal cancer showed better OS (OR for death, 0.432; 95% CI, 0.211-0.882), while those with hypopharyngeal cancer DFS was improved (OR for recurrence, 0.506; 95% CI, 0.328-0.780). CONCLUSION: A survival benefit from surgery may be achieved even in patients with stage IVa HNSC, particularly those with oropharyngeal and laryngeal cancer. Surgery led to a reduction in the recurrence rate in patients with hypopharyngeal cancer.

Actin-Associated Gene Expression is Associated with Early Regional Metastasis of Tongue Cancer.

OBJECTIVES: We aimed to analyze gene expression profile of tongue cancer associated with early lymph node metastasis using the cancer genome atlas (TCGA) data. STUDY DESIGN: Basic research. METHODS: A total of 515 patients with matched RNAseq data of primary tumor and clinical data from TCGA data were extracted. To compare gene expression profile between early T-stage tongue cancer with cervical lymph node metastasis and late T-stage tongue cancer without cervical metastasis, genomic data of following two groups was assessed; 1) group 1: T1/2 and N2/3 (n = 41), 2) group 2: T4 and N0 (n = 65). Using R and limma package in bioconductor program, differentially expressed genes (DEGs) were extracted. Gene ontology and pathway enrichment analysis were performed using the DAVID online tool. FFPE tissue of 285 patients were evaluated for the validation of relevant genes by imunofluorescence (IF) and immunohistochemical (IHC) stain. RESULTS: A total of 225 DEGs were found, and 50 genes were highly significant with absolute fold change over eight. Gene ontology and pathway enrichment analysis revealed that most of the upregulated genes were associated with actin cytoskeleton and included following genes: ANKRD23, NO3, PDLIM3, MUSTN1, TNNT3, MYBPC1, MB, MYH3, TTN, ACTA1, and ACTC1. When comparing tongue cancer with cN0pN0 vs. pN0pN+ using the total tongue cancer cohort of TCGA, ACTA1 was the only parameter which was associated with hidden lymph node metastasis in T1/2 (P = .019). Perineural invasion was significantly associated with high expression of ACTA1 (P < .001). IF and IHC analysis revealed that actin was overexpressed, while E-cadherin and N-cadherin were not significantly different. CONCLUSIONS: Actin associated genes, especially overexpression of ACTA1 may be associated with early regional metastasis of tongue cancer. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:813-819, 2021.

Recipient vessel selection for head and neck reconstruction: A 30-year experience in a single institution.

BACKGROUND: The advance in microsurgical technique has facilitated a proper approach for reconstruction of extensive head and neck defects. For the success of free tissue reconstruction, selection of the recipient vessel is one of the most important factors. However, the vascular anatomy of this region is very complex, and a clear guideline about this subject is still lacking. In this study, we present our 30 years of experiences of free tissue reconstruction for head and neck defects. METHODS: In this retrospective study, we analyzed a total of 138 flaps in 127 patients who underwent head and neck reconstruction using free tissue transfer following tumor resection between October 1986 to August 2019. Patients who underwent facial palsy reconstruction were excluded. Medical records including patient's demographics, detailed operation notes, follow-up records, and photographs were collected and analyzed. RESULTS: Among a total of 127 patients, 10 patients underwent a secondary operation due to cancer recurrence. The most commonly used type of flap was radial forearm flap (n= 107), followed by the anterolateral thigh flap (n= 18) and fibula flap (n= 10). With regard to recipient vessels, superior thyroid artery was most commonly used in arterial anastomosis (58.7%), and internal jugular vein (51.3%) was the first choice for venous anastomosis. The flap survival rate was 100%. Four cases of venous thrombosis were resolved with thrombectomy and re-anastomosis. CONCLUSION: Superior thyroid artery and internal jugular vein were reliable choices as recipient vessels. Proper recipient vessel selection could improve the result of head and neck reconstruction.

Enhancement of aberrantly modified integrin­mediated cell motility in multicellular tumor spheroids.

Multicellular tumor spheroids (MTSs) of malignant cells can display cell­cell and cell­matrix interactions, different from monolayer cultures. The objective of the present study was to examine difference in intercellular and cell­matrix interaction between monolayered cultures and spheroid cultures. Expression levels of cell adhesion molecules (CAMs) and epithelial­mesenchymal transition (EMT) signaling molecules in monolayered cells and MTS cells were compared. The motility of single cells dispersed from each culture was evaluated using a live­cell imaging device. The effect of an E­cadherin neutralizing antibody, DECMA, was also compared between the two cultures. Among various CAMs, only E­cadherin was increased in MTSs. The motility of single cells dispersed from MTSs was higher than that from monolayered cells. Compared with monolayered cells, the molecular weight (MW) of ß1 integrin was decreased during MTS formation, particularly during the early stage. This notable reduction was maintained when DECMA was used to treat MTSs. Additionally, the expression levels of the EMT signaling molecules Snail and ILK increased more in MTSs than in monolayered cells. The blocking of E­cadherin elicited increased expression levels of EMT molecules and cellular motility only in MTSs. In conclusion, the alteration of E­cadherin expression and presence of low­MW ß1 integrin in MTS may enhance cell motility via the upregulation of EMT signaling molecules that may be intensified by blocking E­cadherin.

Assessment of Chronological Volume Changes in Radial Forearm Free Flaps for Tongue Cancer.

OBJECTIVE: The radial forearm free flap (RFFF) is a commonly used free flap for tongue cancer. Postoperative changes in the volume of free flap are known to influence the functional restoration of the resected tongue. This study aimed to estimate chronological volume changes in RFFFs for tongue cancer and to determine the clinical factors affecting these changes. METHODS: Clinical data for 19 patients who underwent RFFF reconstruction for tongue cancer between May 2004 and September 2013 were retrospectively reviewed. The flap volume was measured 3, 6, 12, 24, and 36 months after surgery using CT and the Picture Archiving and Communication System software. RESULTS: Relative to volumes at 3 months, median flap volumes decreased to 98.55, 70.16, 62.86, and 58.84% at 6, 12, 24, and 36 months, respectively. None of the evaluated parameters were correlated with volume changes. CONCLUSIONS: Over time, the volume of RFFF in the tongue decreased. Considering this, free flap reconstruction should be carried out in tongue cancer surgery.

Objective Assessment of Postoperative Swallowing Difficulty Through Ultrasound in Patients Undergoing Thyroidectomy.

Swallowing discomfort is a common postoperative complaint in patients undergoing thyroidectomy. Contraction of the strap muscles might cause resistance to elevation of the laryngotracheal unit, and downward movement of the laryngotracheal unit may lead to swallowing discomfort. However, few studies have evaluated the mechanism related to limited laryngotracheal elevation after thyroidectomy. We aimed to objectively verify the presence of postoperative impaired laryngotracheal elevation through ultrasound evaluation in patients undergoing thyroidectomy and evaluate its relationship with limitation of laryngotracheal elevation. This is a prospective clinical study. Among patients undergoing hemithyroidectomy and total thyroidectomy, the patients who were followed up for ≥ 6 months were selected (N = 40). Ultrasound evaluation was done preoperatively and at 1, 3, and 6 months postoperatively. Laryngotracheal movement was recorded and the length of elevation was measured. Symptom after thyroidectomy was evaluated through swallowing-related items of thyroidectomy-related voice questionnaire. Ultrasound evaluation verified the presence of limited laryngotracheal elevation postoperatively in patients undergoing thyroidectomy. After thyroidectomy, the swallowing-related score was significantly increased, and was recovered time-dependently at 1 month. Laryngotracheal elevation showed significant decrease after thyroidectomy. The symptom score of swallowing was significantly correlated with the length of laryngotracheal elevation. Post-thyroidectomy ultrasound evaluation verified that laryngotracheal elevation was significantly impaired. Presence of adhesion between the laryngotracheal unit and the superficial soft tissue was the probable cause of the limitation at 6 months after thyroidectomy. The length of laryngotracheal elevation was related to the symptom score of swallowing after thyroid surgery.

Role of Matrix Metalloproteinases 7 in the Pathogenesis of Laryngopharyngeal Reflux: Decreased E-cadherin in Acid exposed Primary Human Pharyngeal Epithelial Cells.

Cleavage of E-cadherin and the resultant weakness in the cell-cell links in the laryngeal epithelium lining is induced by exposure to acidic contents of the refluxate. Herein, we aimed to evaluate the role of matrix metalloproteinases (MMPs) in inducing E-cadherin level changes following acid exposure to the human pharyngeal mucosal cells. E-cadherin levels were inversely correlated with the duration of acid exposure. Treatment with actinonin, a broad MMP inhibitor, inhibited this change. Immunocytochemical staining and transepithelial permeability test revealed that the cell surface staining of E-cadherin decreased and transepithelial permeability increased after acid exposure, which was significantly inhibited by the MMP inhibitor. Among the various MMPs analyzed, the mRNA for MMP-7 in the cellular component was upregulated, and the secretion and enzymatic activity of MMP-7 in the culture media increased with the acid treatment. Consequently, MMP-7 plays a significant role in the degradation of E-cadherin after exposure to a relatively weak acidic condition that would be similar to the physiologic condition that occurs in Laryngopharyngeal reflux disease patients.

Clinical Analysis of Pediatric Thyroid Cancer: A Single Medical Institution Experience of 18 Years.

OBJECTIVE: The incidence of pediatric thyroid cancer is relatively low compared to the disease in adults. This study aims to present the data in our institution on pediatric thyroid cancer patients, with particular emphasis on the risk factors of recurrence together with treatment outcomes. SUBJECTS AND METHODS: Between January 2000 and July 2018, patients <20 years who were diagnosed with thyroid carcinoma and primarily treated with surgery at a major large-volume tertiary medical center specializing in thyroid cancer were enrolled. A total of 83 patients were eligible for this study. RESULTS: The majority of the studied patients were girls and adolescents (age ≥13 years). Papillary thyroid carcinoma (PTC) was the most common pathology (n = 74). PTC tumors >1 cm showed higher rate of lymph node metastasis and extrathyroidal extension than tumors ≤1 cm. All patients survived with nine PTC patients who displayed treatment failure. Age, tumor size, multifocality, lateral lymph node metastasis, and postoperative thyroglobulin levels were significant prognosticators for disease recurrence. CONCLUSION: Pediatric thyroid cancer is relatively rare and should be considered a specific disease entity with respect to the thyroid cancer in adults, since there are several distinctive characteristics.

Comparison of functional outcomes after total thyroidectomy and completion thyroidectomy: Hypoparathyroidism and postoperative complications.

OBJECTIVE: This study aimed to investigate differences in functional outcomes of postoperative complications and hypoparathyroidism between patients who underwent completion thyroidectomy (CT) after thyroid lobectomy or total thyroidectomy (TT) as an initial treatment. MATERIALS AND METHODS: We retrospectively analyzed the differences of functional outcomes after completion thyroidectomy and total thyroidectomy without lymph node dissection. We reviewed the medical records of 396 patients who underwent CT or TT for thyroid disease at Korea University Guro Hospital from March 2002 to August 2016. RESULTS: Of the 396 patients, 32 underwent CT and 364 underwent TT. There were 72 male patients and 324 female patients. Transient hypoparathyroidism was observed in 4 (9.4%) of the CT patients and 97 (26.6%) of the TT patients, with a statistically significant difference (p=0.031). Permanent hypoparathyroidism was observed in 1 patient (3.1%) in the CT group and in 13 patients (3.6%) in the TT group, which was not significantly different. There were no significant differences in the postoperative complication of temporary recurrent laryngeal nerve injury, wound infection, and hematoma between two patients group. CONCLUSION: The incidence of transient hypoparathyroidism in CT patients was significantly lower than in TT patients. These safety and functional superiority of CT should be considered when determining the scope and extent of operation in patients requiring surgery for thyroid disease.