Postoperative Chyle Leak Rate Following Neck Dissection for Squamous Cell Carcinoma Versus Papillary Thyroid Cancer.

OBJECTIVES: Compare the rates of post-operative chyle leak following therapeutic lateral neck dissection during treatment of papillary thyroid carcinoma (PTC) versus squamous cell carcinoma (SCC) of the head and neck. METHODS: A retrospective analysis of 226 consecutive neck dissections in 201 patients who underwent therapeutic neck dissection involving at least levels II-IV with a final pathologic diagnosis of mucosal SCC of the head and neck or PTC from 2010 to 2020. Specific cases of chyle leak were reviewed. Surgical factors associated with chyle leak were analyzed using logistic regression analysis. Duration of chyle leak was assessed by the Kaplan-Meier curve, and time-to-resolution was analyzed by Cox proportional hazard analysis. RESULTS: Postoperative chyle leak was encountered in 15 (6.6%) neck dissections, eight (12.3%) in PTC, and seven (4.3%) in SCC. High-volume chyle leak and chyle leak requiring operative intervention were only encountered in neck dissections performed for PTC. Chyle leak was significantly associated with PTC on univariable analysis (OR 3.08, p = 0.037), but not on multivariable analysis (OR 1.35, p = 0.711). High-volume chyle leak and the need for operative intervention were associated only with PTC patients (OR 23.6, p = 0.006; OR 18.09, p = 0.023 respectively). Median duration of chyle leak was 12.1 days among patients with SCC, and 20.5 days among patients with PTC (p = 0.089). CONCLUSIONS: Among 201 patients undergoing therapeutic neck dissection, chyle leak was associated with PTC pathology on univariable but not multivariable analysis. However, high-volume leaks and leaks requiring operative intervention only occurred among patients with PTC. LEVEL OF EVIDENCE: level III Laryngoscope, 133:2959-2964, 2023.

Tuft Cells Are Present in Submandibular Glands Across Species.

Tuft cells are bottle-shaped, microvilli-projecting chemosensory cells located in the lining of a variety of epithelial tissues and, following their identification approximately 60 years ago, have been linked to immune system function in a variety of epithelia. Until recently, Tuft cells had not been convincingly demonstrated to be present in salivary glands with their detection by transmission electron microscopy only shown in a handful of earlier studies using rat salivary glands, and no follow-up work has been conducted to verify their presence in salivary glands of other species. Here, we demonstrate that Tuft cells are present in the submandibular glands of various species (i.e., mouse, pig and human) using transmission electron microscopy and confocal immunofluorescent analysis for the POU class 2 homeobox 3 (POU2F3), which is considered to be a master regulator of Tuft cell identity.

Occult Metastases During Salvage Oral Cavity and Oropharyngeal Free Flaps: Oncologic Outcomes.

OBJECTIVES: To define rates of occult metastases in salvage oral cavity and oropharyngeal cancer resection requiring free flap, to examine the location of occult metastases, and to determine associations between occult metastasis and survival. STUDY DESIGN: Retrospective cohort study. SETTING: Two tertiary care referral centers. METHODS: We identified previous cases of irradiation with recurrent or second primary oral cavity or oropharyngeal squamous cell carcinoma that had no evidence of regional metastasis and required free tissue transfer reconstruction of the primary site. Patients who underwent elective neck dissection or exploration were reviewed. The main outcome measures were the presence and location of occult nodal metastasis. Disease-free survival and overall survival were measured. Odds ratios and hazard ratios were used for analysis. RESULTS: A total of 83 patients were included: 52 with oral cavity primary tumors and 31 with oropharynx. An overall 78 (94%) underwent elective salvage neck dissection. Occult metastases were found in 9 (11.5%) patients. The most common nodal station for occult metastasis was level 2. Neither elective neck dissection nor the presence of occult metastasis was significantly associated with regional disease-free or overall survival. Oropharyngeal primary tumors were associated with higher risk of occult metastasis (odds ratio, 1.38; P < .01) and worse overall survival (hazard ratio, 2.09; P = .01). CONCLUSION: There is a low incidence of occult metastasis in postradiated recurrent or second primary oral cavity and oropharyngeal tumors. Elective neck dissection and occult nodal metastases were not associated with regional or overall survival. This series may help surgeons make decisions regarding the extent of neck surgery after prior radiation, especially when free flap reconstruction is required.

Effectiveness of gabapentin in reducing opioid requirements after radiation in head and neck cancer in a single institution.

BACKGROUND: Gabapentin has been shown to reduce opioid use in head and neck cancer patients. Here, we examine the efficacy of prophylactic gabapentin at reducing opioid use in these patients at our institution. METHODS: A retrospective study of patients receiving radiation was performed, using patients from our previous study as controls. Risk factors for opioid use at 3 and 6 months were determined using univariate and multivariate analyses. RESULTS: In total, 53/185 patients were treated with gabapentin, 39.6% of which took opioids at 3 months vs. 58.3% in the non-gabapentin cohort (p = 0.021). Gabapentin was independently associated with less opioid use on multivariate analysis at 3 months (OR 0.47, 95% CI 0.24-0.9). Gastrostomy tube dependence and pretreatment opioid use were associated with chronic opioid use despite gabapentin. CONCLUSIONS: Gabapentin is effective at expediting opioid tapering in head and neck cancer patients who are not gastrostomy tube dependent or taking opioids pretreatment.

Safety of the "incidental" neck dissection or exploration during free tissue transfer after head and neck irradiation.

IMPORTANCE: Patients with either local recurrence of head and neck cancer or osteoradionecrosis after prior radiation treatment often require free tissue transfer for optimal reconstruction. In this setting, neck exploration for vessels is necessary, and an "incidental" neck dissection is often accomplished despite clinically negative cervical lymph nodes. While neck surgery in the post-radiated setting is technically challenging, the safety of post-radiated elective neck dissection or neck exploration for vessels is not well-studied, especially for patients undergoing non-laryngectomy salvage resections. OBJECTIVE: To define intraoperative and postoperative surgical complications for patients undergoing elective neck dissection or exploration with free tissue transfer reconstruction in the post-radiated setting, with attention to complications from neck surgery. DESIGN: Retrospective cohort study. Patient charts from May 2005 to April 2020 were reviewed. SETTING: Tertiary care referral center. PARTICIPANTS: Patients underwent free tissue transfer after prior head and neck irradiation for non-laryngeal local cancer recurrence or second primary, osteoradionecrosis, or for sole reconstructive purposes. Patients with clinically positive neck disease were excluded. MAIN OUTCOMES AND MEASURES: Intraoperative and postoperative complications including unplanned vessel or nerve injury, hematoma, chyle leak, wound dehiscence, wound infection, fistula formation, flap failure, and perioperative medical complications. Neck exploration and neck dissection patient outcomes were compared by Fisher exact test. RESULTS: Seventy-two patients (56 men and 16 women) of average age sixty-one (range 34-89) were identified with average follow-up 25.7 months. Most patients (78%) underwent salvage neck dissection, and the rest underwent neck exploration for vessels only. There were five intraoperative neck complications: three vessel injuries and two nerve injuries. There were twenty-six postoperative surgical complications among eighteen patients. There was no difference in surgical complications whether patients underwent neck dissection or exploration only. Two partial and two complete flap failures occurred. There were nine perioperative medical complications among six patients. CONCLUSIONS AND RELEVANCE: Elective neck dissection or exploration among patients undergoing free tissue transfer in the post-radiated setting carries a risk of both intraoperative and postoperative surgical complications. The present study defines risk of complications and helps to inform patient discussions for risk of complications in the post-radiated setting.

Utility of CT in the workup of adults with sore throat in the emergency department.

OBJECTIVE: The goal of this study was to determine if computed tomography (CT) added any clinical information that was incorporated into the decision regarding treatment for patients who presented to the Emergency Department (ED) with sore throat. METHODS: A retrospective chart review of adult patients who presented to the ED with a chief complaint of sore throat who subsequently underwent CT during that ED visit between 1/1/18 and 12/31/18 at our tertiary academic health center was performed. The association between palatal bulge on Otolaryngology physical exam with successful drainage procedure was examined. The mean Hounsfield units (HU) and maximum dimension of measurable fluid collection on CT were compared between patients who underwent a successful drainage procedure and those who did not undergo a drainage procedure or attempted drainage was unsuccessful. RESULTS: Ninety-four patients met inclusion criteria, with 53% (50/94) men. Of the 22 patients with a palatal bulge on physical examination by Otolaryngology, 86% (19/22) underwent a successful drainage procedure (p < 0.001) when compared to those not undergoing successful drainage. Notably, 56% (53/94) of CT scans were interpreted as normal or tonsillitis. The mean HU was 42.0 in those patients who underwent a successful drainage procedure and 74.1 in those who did not undergo a drainage procedure (p < 0.001). Overall, 21/35 fluid collections had a palatal bulge (p < 0.001). CONCLUSION: Palatal bulge is a reliable finding in identifying patients with a drainable peritonsillar abscess, and CT scans could largely be avoided in patients without physical exam findings suggestive of more extensive deep neck space abscesses. If a CT scan is obtained, HU should be measured and incorporated into the shared decision-making process with the patient.

Travel distance is associated with stage at presentation and laryngectomy rates among patients with laryngeal cancer.

BACKGROUND: The impact of travel distance on stage at presentation and management strategies of laryngeal squamous cell carcinoma (SCC) is unknown. We investigated this relationship. METHODS: Retrospective review of patients with laryngeal SCC in the National Cancer Data Base from 2004 to 2016. Multivariate analysis determined relationships between travel distance, sociodemographic, geographic, and hospital factors. Logistic regression determined the influence of travel distance on T-stage and overall stage at presentation, and receipt of total laryngectomy. RESULTS: Sixty thousand four hundred and thirty-nine patients were divided into groups based on distance to treatment: short (<12.5 miles); intermediate (12.5-49.9 miles); and long (>50 miles). Increased travel was associated with T4-stage (intermediate vs. short OR 1.11, CI 1.04-1.18, p = 0.001; long vs. short OR 1.5, CI 1.36-1.65, p < 0.001), and total laryngectomy (intermediate vs. short OR 1.40, CI 1.3-1.5, p ≤ 0.001; long vs. short OR 2.52, CI 2.28-2.79, p ≤ 0.001). In T4 disease, total laryngectomy was associated with improved survival compared to nonsurgical treatment (HR 0.75, CI 0.70-0.80, p < 0.001) regardless of travel distance. CONCLUSION: Longer travel distance to care is associated with increased stage at presentation, rate of laryngectomy, and improved survival in advanced laryngeal SCC. Health policy efforts should be directed towards improving early access to diagnosis and care.

Treatment of Cutaneous Melanoma of the Head and Neck With Wide Local Excision Versus Mohs.

OBJECTIVES: Determine if Mohs micrographic surgery (MMS) is associated with improved overall survival compared to wide local excision (WLE) when treating cutaneous melanoma of the head and neck (CMHN) and to report the proportion of patients treated with MMS versus WLE who also underwent sentinel lymph node biopsy (SLNB). METHODS: Retrospective cohort study of the National Cancer Database (NCDB) analyzing the overall survival of patients diagnosed with T1 to T4 CMHN between 2004 and 2016 who were treated with either WLE or MMS. RESULTS: On multivariable analysis, treatment with WLE versus MMS was not significantly associated with overall survival (HR, 1.094; 95% CI, 0.997-1.201). On multivariable analysis, lower Charlson-Deyo score (HR, 0.489; 95% CI, 0.427-0.560), negative margins (HR, 0.754; 95% CI, 0.705-0.807), and N0 classification (HR 0.698; 95% CI, 0.668-0.730) were associated with improved overall survival. Seventy-seven percent of patients treated with MMS did not undergo SLNB, while 45% of patients treated with WLE did not undergo SLNB (P < .001). CONCLUSIONS: No difference in overall survival between MMS and WLE when treating CMHN. Patients treated with MMS were significantly less likely to undergo SLNB, suggesting an opportunity for enhancement of multidisciplinary care. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2490-2496, 2021.

Tracheotomy Outcomes in the Medical Intensive Care Unit.

This is a retrospective chart review of 161 MICU patients who underwent tracheotomy by the Otolaryngology service at the University of Missouri Hospital from April 2015 through March 2018. The objectives of this study were to describe long term outcomes of patients who underwent tracheotomy, and identify any clinical variables associated with these outcomes. One-year mortality was 37% (50/161), and on multivariate analysis only age (p=0.001) was associated with mortality.

Positive Margins in Cutaneous Melanoma of the Head and Neck: Implications for Timing of Reconstruction.

OBJECTIVE: The aim of this study is to identify clinicopathologic features associated with positive margins after surgical treatment of cutaneous melanoma of the head and neck (CMHN). STUDY DESIGN: Retrospective cohort study. SETTING: National Cancer Database. METHODS: A retrospective analysis of the National Cancer Database was performed of patients diagnosed with CMHN between 2004 and 2016. Univariate and multivariate analyses examining the association of clinicopathologic features with positive margins were performed via logistic regression analysis. RESULTS: A total of 101,560 patients met inclusion criteria. The incidence of positive margins was 5.0% (5128/101,560). Patients were significantly more likely to have positive margins with the following: increasing age (P < .001; odds ratio [OR], 1.028; 95% CI, 1.026-1.031), the lip subsite (P < .001; OR, 1.664; 95% CI, 1.286-2.154), the eyelid subsite (P < .001; OR, 2.380; 95% CI, 1.996-2.838), the face subsite (P < .001; OR, 1.215; 95% CI, 1.133-1.302), the lentigo maligna/lentigo maligna melanoma subtype (P = .019; OR, 1.099; 95% CI, 1.016-1.188), the desmoplastic subtype (P < .001; OR, 1.455; 95% CI, 1.261-1.680), the spindle cell subtype (P = .006; OR, 1.276; 95% CI, 1.073-1.516), and advanced pT classification. Patients with male sex (P < .001; OR, 0.733; 95% CI, 0.687-0.782) and without ulceration (P < .001; OR, 0.803; 95% CI, 0.736-0.876) were significantly less likely to have positive margins. CONCLUSION: The following have been identified as clinicopathologic features associated with positive margins after surgical treatment of CMHN: increasing age, female sex, the lip subsite, the eyelid subsite, the face subsite, ulceration, the lentigo maligna/lentigo maligna melanoma subtype, the desmoplastic subtype, the spindle cell subtype, and increasing pT classification.

Implications of Tumor Size, Subsite, and Adjuvant Therapy on Outcomes in pT4aN0 Oral Cavity Carcinoma.

OBJECTIVE: To determine if tumor size, subsite, and adjuvant radiation therapy (AXRT) are associated with overall survival (OS) in patients with pT4aN0 oral cavity squamous cell carcinoma (OSCC) who underwent mandibulectomy with negative surgical margins (NSMs). STUDY DESIGN: Retrospective cohort study. SETTING: National Cancer Database (NCDB). SUBJECTS AND METHODS: Retrospective analysis of the NCDB that included patients diagnosed with pT4aN0 OSCC who underwent mandibulectomy with NSMs between 2004 and 2015. The association of age, Charlson-Deyo score (CDS), tumor size, subsite, and AXRT with OS was analyzed. The cases were divided into 3 subgroups based on maximal tumor dimension for subgroup analysis; tumors ≤2.0 cm, tumors 2.1 to 4.0 cm, and tumors >4.0 cm. RESULTS: For the entire cohort; age (P < .001; hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.02-1.03), CDS (P = .013; HR, 0.57; 95% CI, 0.37-0.89), tongue subsite (P = .003; HR, 2.01; 95% CI, 1.27-3.40), floor of mouth subsite (P = .001; HR, 1.76; 95% CI, 1.28-2.42), tumor size (P < .001; HR, 0.57; 95% CI, 0.45-0.72), and AXRT (P < .001; HR, 1.46; 95% CI, 1.24-1.72) were associated with OS on multivariate analysis. On subgroup analysis, AXRT not significantly associated with OS in patients with gingival, hard palate, retromolar trigone, and not specified tumors ≤2.0 cm (P = .323; HR, 1.29; 95% CI, 0.78-2.15). CONCLUSIONS: In patients with pT4aN0 OSCC who underwent mandibulectomy with NSMs, age, CDS, tongue subsite, floor of mouth subsite, tumor size, and AXRT are associated with OS. AXRT was not significantly associated with overall survival in patients with gingival, hard palate, retromolar trigone, and not specified tumors ≤2.0 cm.

Utility of Intraoperative Frozen Section in Large Thyroid Nodules.

OBJECTIVE: To determine if the routine use of intraoperative frozen section (iFS) results in cost savings among patients with nodules >4 cm with nonmalignant cytology undergoing a thyroid lobectomy. STUDY DESIGN: Case series with chart review; cost minimization analysis. SETTING: Single academic center. SUBJECTS AND METHODS: Records were reviewed on a consecutive sample of 48 patients with thyroid nodules >4 cm and nonmalignant cytology who were undergoing thyroid lobectomy in which iFS was performed between 2010 and 2015. A decision tree model of thyroid lobectomy with iFS was created. Comparative parameters were obtained from the literature. A cost minimization analysis was performed comparing lobectomy with and without iFS and the need for completion thyroidectomy with costs estimated according to 2014 data from Medicare, the Bureau of Labor Statistics, and the Nationwide Inpatient Sample. RESULTS: The overall malignancy rate was 25%, and 33% of these malignancies were identified intraoperatively. When the malignancy rates obtained from our cohort were applied, performing routine iFS was the less costly scenario, resulting in a savings of $486 per case. When the rate of malignancy identified on iFS was adjusted, obtaining iFS remained the less costly scenario as long as the rate of malignancies identified on iFS exceeded 12%. If patients with follicular lesions on cytology were excluded, 50% of malignancies were identified intraoperatively, resulting in a savings of $768 per case. CONCLUSIONS: For patients with nodules >4 cm who are undergoing a diagnostic lobectomy, the routine use of iFS may result in decreased health care utilization. Additional cost savings could be obtained if iFS is avoided among patients with follicular lesions.

Impact of PET/CT on Staging and Treatment of Advanced Head and Neck Squamous Cell Carcinoma.

OBJECTIVE: To understand the effects of positron emission tomography/computed tomography (PET/CT) evaluation on patients with previously untreated head and neck squamous cell carcinoma (HNSCC) with clinical evidence of regional lymph node involvement. STUDY DESIGN: Prospective blinded study. SETTING: Tertiary care cancer center. SUBJECTS AND METHODS: Informed consent was obtained and data collected from 52 consecutive previously untreated patients with HNSCC and clinical evidence of cervical metastasis. All patients underwent conventional evaluation for HNSCC and whole body PET/CT. Data were evaluated by 5 independent reviewers, who performed TNM staging per the American Joint Committee on Cancer (seventh edition) manual and proposed a treatment plan prior to viewing, and after reviewing, PET/CT. Cases where at least 3 of 5 reviewers agreed were considered significant. RESULTS: There were 0 patients for whom review of the PET/CT altered the T-class assessment (95% CI, 0-6.8), 12 (23.1%) for whom PET/CT altered N classification (95% CI, 12.5-34.5), and 2 (3.8%) for whom PET/CT altered the M classification (95% CI, 0.5-13.2). For 5 patients (9.6%), overall stage was altered per PET/CT review (95% CI, 3.2-21). For 3 patients (5.8%), PET/CT findings prompted reviewers to alter treatment recommendations (95% CI, 1.2-15.9). CONCLUSION: When added to more conventional patient evaluation, PET/CT results in changes to the TNM categories, but overall staging and treatment were less frequently affected. Whether PET/CT should be used routinely for patients with stage III and IV HNSCC is still subjective and merits further study.

Peer Feedback on Collaborative Learning Activities in Veterinary Education.

Collaborative learning activities are an increasingly prominent feature of veterinary curricula that have been redesigned to achieve competency-based graduate learning outcomes. This evolution challenges the traditional individualistic approach to veterinary education and necessitates revisions to assessment and feedback practices to ensure constructive alignment. Peer feedback has been widely reported in the medical education literature as a teaching intervention in collaborative learning settings, with learning gains reported for students who receive and provide peer feedback. In this setting, peer feedback has been demonstrated to provide valuable formative feedback on professional behaviors and skills. However, there are very few such reports in the veterinary education literature to date. Barriers to the introduction of this approach can include teacher and student perceptions, and concerns around validity and reliability. This review aimed to provide an overview of current evidence regarding peer feedback on collaborative learning activities in higher education, and to explore opportunities and challenges for the introduction of peer feedback in the context of veterinary education. We contend that early and repeated provision of formative peer feedback can provide an opportunity to scaffold the development of crucial core competencies within veterinary education, including the self-regulated learning skills required to work in collaborative teams, and interpret and act on feedback.

Impact of perioperative hyperglycemia in patients undergoing microvascular reconstruction.

BACKGROUND: The effects of perioperative hyperglycemia on complications and outcomes in microvascular reconstruction have not been reported in the literature. METHODS: A retrospective cohort of 203 patients undergoing microvascular reconstruction was generated. Perioperative glucose levels and clinical factors were tested for associations with complications using simple and multivariate analyses. RESULTS: Hyperglycemia (blood glucose ≥ 180 mg/dL) occurred in 91 patients (44.8%) perioperatively, and was associated with increased rates of surgical complications, medical complications, surgical site infections, fistulas, and wound dehiscence. On univariate analysis, a more strict definition of hyperglycemia (blood glucose ≥ 165 mg/dL) was significantly associated with greater rates of venous thrombosis, although this lost statistical significance on multivariate analysis. CONCLUSION: Perioperative hyperglycemia occurs commonly in patients undergoing microvascular reconstruction and is associated with higher rates of complications, independent of a preexisting diagnosis of diabetes mellitus. Further research is needed to define the ideal glycemic target in this population.

Implementing the Flipped Classroom in a Veterinary Pre-clinical Science Course: Student Engagement, Performance, and Satisfaction.

There has been a recent move toward active learning pedagogies in veterinary education, with increasing use of a blended approach that incorporates both online resources and live classroom sessions. In this study, an established veterinary pre-clinical course in introductory animal health was transitioned from a traditional didactic lecture delivery mode to a flipped classroom approach with core content delivered online. This study compared the experiences of two cohorts of students who studied the same course in the different formats in consecutive years. Online learning resources included short video segments and a variety of short problems and activities. Online materials were complemented with weekly small-group case-based learning classes facilitated by academic staff. A mixed methods evaluation strategy was applied using student grades, surveys, and focus groups to compare student academic performance, satisfaction, and engagement between the two cohorts. The flipped classroom cohort achieved significantly higher grades in the written answer section of the final examination. Student satisfaction with learning resources was also higher in this cohort. However, satisfaction with other aspects of the course was largely the same for both cohorts. This study revealed some of the challenges associated with achieving adequate student preparation for class using online resources. The outcomes of this study have implications for veterinary educators considering the design and development of new online learning resources.

Economic Impact of Frozen Section for Thyroid Nodules with "Suspicious for Malignancy" Cytology.

Objective To perform a cost analysis of the routine use of intraoperative frozen section (iFS) among patients undergoing a thyroid lobectomy with "suspicious for malignancy" (SUSP) cytology in the context of the 2015 American Thyroid Association guidelines. Study Design Case series with chart review; cost minimization analysis. Setting Academic. Subjects and Methods Records were reviewed for patients with SUSP cytology who underwent thyroid surgery between 2010 and 2015 in which iFS was utilized. The diagnostic test performance of iFS and the frequency of indicated completion/total thyroidectomies based on the 2015 guidelines were calculated. A cost minimization analysis was performed comparing lobectomy, with and without iFS, and the need for completion thyroidectomy according to costs estimated from 2014 data from Medicare, the Bureau of Labor Statistics, and the Nationwide Inpatient Sample. Results Sixty-five patients met inclusion criteria. The malignancy rate was 61.5%, 45% of which was identified intraoperatively. The specificity and positive predictive value were 100%. The negative predictive value and sensitivity were 83% and 95%, respectively. Completion/total thyroidectomy was indicated for 9% of patients; 83% of these individuals had findings on iFS that would have changed management intraoperatively. Application of the new guidelines would have resulted in a significant reduction in the frequency of conversion to a total thyroidectomy when compared with the actual management (26.1% vs 7.7%, P = .005). Performing routine iFS was the less costly scenario, resulting in a savings of $474 per case. Conclusion For patients with SUSP cytology undergoing lobectomy, routine use of iFS would result in decreased health care utilization.

The futility of intraoperative frozen section in the evaluation of follicular thyroid lesions.

OBJECTIVE: Investigate the utility of intraoperative frozen section (iFS) in patients with follicular thyroid lesions following publication of the 2015 American Thyroid Association (ATA) guidelines. STUDY DESIGN: Retrospective chart review. METHODS: Patient demographics, preoperative cytology, frozen pathology, and final pathology were reviewed on patients undergoing thyroid surgery at a tertiary care hospital in which iFS was utilized over a 5-year period. The test performance of iFS and the frequency of indicated completion/total thyroidectomies pre- and postpublication of the 2015 ATA guidelines were calculated. RESULTS: One hundred and one patients met inclusion criteria: 54 patients with follicular lesions of undetermined significance (FLUS) and 47 patients with a cytologic diagnosis of suspicious for follicular neoplasm/follicular neoplasm. The malignancy rate was 36%, but only 14% of malignancies were identified on iFS. A definitive benign or malignant diagnosis was given on iFS in only 21% of cases, and operative management was altered in two cases as a result of iFS. There was a statistically significant reduction in the frequency of indicated total/completion thyroidectomies based on high-risk features as a result of the 2015 ATA guidelines compared to prior recommendations (20.8% vs. 5.0%, P = < 0.001). None of these patients had findings on iFS that would have altered management intraoperatively. CONCLUSION: Intraoperative frozen section offers minimal diagnostic utility in the evaluation of follicular thyroid lesions. Updates in the 2015 ATA guidelines further diminish its potential to impact management intraoperatively. Significant improvements in its ability to identify malignancies would be needed to justify its use. LEVEL OF EVIDENCE: 4. Laryngoscope, 128:1501-1505, 2018.

Immunoselected STRO-3+ mesenchymal precursor cells reduce inflammation and improve clinical outcomes in a large animal model of monoarthritis.

BACKGROUND: The purpose of this study was to investigate the therapeutic efficacy of intravenously administered immunoselected STRO-3 + mesenchymal precursor cells (MPCs) on clinical scores, joint pathology and cytokine production in an ovine model of monoarthritis. METHODS: Monoarthritis was established in 16 adult merino sheep by administration of bovine type II collagen into the left hock joint following initial sensitization to this antigen. After 24 h, sheep were administered either 150 million allogeneic ovine MPCs (n = 8) or saline (n = 8) intravenously (IV). Lameness, joint swelling and pain were monitored and blood samples for leukocytes and cytokine levels were collected at intervals following arthritis induction. Animals were necropsied 14 days after arthritis induction and gross and histopathological evaluations were undertaken on tissues from the arthritic (left) and contralateral (right) joints. RESULTS: MPC-treated sheep demonstrated significantly reduced clinical signs of lameness, joint pain and swelling compared with saline controls. They also showed decreased cartilage erosions, synovial stromal cell activation and angiogenesis. This was accompanied by decreased infiltration of the synovial tissues by CD4+ lymphocytes and CD14+ monocytes/macrophages. Over the 3 days following joint arthropathy induction, the numbers of neutrophils circulating in the blood and plasma concentrations of activin A were significantly reduced in animals administered MPCs. CONCLUSIONS: The results of this study have demonstrated the capacity of IV-administered MPCs to mitigate the clinical signs and some of the inflammatory mediators responsible for joint tissue destruction in a large animal model of monoarthritis.