The Effect of Hemithyroidectomy in Papillary Thyroid Carcinoma with an Exclusive Involvement of the Recurrent Laryngeal Nerve: A Retrospective Study with a Propensity Score-Matched Analysis

BACKGROUND

Involvement of the recurrent laryngeal nerve (RLN) in papillary thyroid carcinoma (PTC) is an important prognostic factor and is associated with a higher risk of recurrence. This study aimed to retrospectively analyze the outcomes of patients treated with hemithyroidectomy (HT) in PTC patients with an exclusive RLN invasion who could not tolerate staged surgery, did not wish to undergo another operation, or had other reasons.

METHODS

A retrospective review was conducted on 163 patients with PTC and exclusive RLN involvement at our institution between 2013 and 2019. Patients were divided into a total thyroidectomy (TT) group and HT group. The clinicopathologic factors and prognostic outcomes were compared between the two groups. A propensity score-matched analysis was carried out to reduce selection bias, with the following covariates: gender, age, tumor size, multifocality, central lymph node metastasis (CLNM), and RLN resection. The Kaplan-Meier method was used for a comparison of recurrence outcomes.

RESULTS

In the baseline data of the 163 PTC patients, tumor size (p < 0.001), multifocality (p = 0.011), CLNM (p < 0.001), and RLN resection (p < 0.008) in the TT and HT groups differed significantly, whereas age and gender did not differ between the two groups. The TT group reported significantly higher temporary and permanent hypoparathyroidism than the HT group (p < 0.001 and p = 0.042, respectively). With 72-month median follow-up, 11 (6.7%) patients developed recurrence. After propensity score matching, 24 patients with HT and 43 patients with TT were included. Recurrence-free survival (RFS) in the matched samples showed no difference between the TT and HT groups (p = 0.092).

CONCLUSION

Our results indicate that HT may be a feasible treatment for PTC patients with exclusive RLN involvement in specific circumstances without significantly increasing the risk of recurrence. Performing a thorough preoperative examination is crucial to exclude multifocal tumors and lymph node metastasis before undergoing HT.

Impact of thyroid carcinoma invasion of recurrent laryngeal nerve on cervical lymph node metastasis

PURPOSE

Papillary thyroid carcinoma (PTC) has a favorable prognosis. However, involvement of the recurrent laryngeal nerve (RLN) significantly increases the risk of recurrence. RLN invasion was an important factor in determining the extent of thyroid surgery. The purpose of this study was to compare clinicopathologic features and characterize risk factors of central and lateral lymph node metastasis (LLNM) of RLN invasion in patients with PTC.

METHODS

A retrospective review was conducted of 130 patients with PTCs who had exclusive tumor involvement of the RLN at our institution between January 2014 and February 2019. All patients underwent total thyroidectomy and high-dose radioactive iodine (RAI) therapy. The clinicopathologic factors and prognostic outcomes of the patients with solitary and multiple RLN involvements were compared. Kaplan-Meier method was performed to compare the outcomes of tumor recurrence. Univariate and multivariate logistic regression analyses were used to identify risk factors associated with LLNM.

RESULTS

The invasion of the RLN was similar on both sides, with 58.5% on the right, 40.0% on the left, and 1.5% on both sides. Significant differences were observed in tumor size (p < 0.001), lymph node metastasis classification (p = 0.002), RLN resection (p < 0.001), and thyroglobulin (p = 0.010) in the solitary and multiple groups. During the median follow-up of 67 months, 9 (6.9%) patients developed recurrence. There were no statistical differences in recurrence for age, tumor size, gender, multifocality, lymph node metastasis (LNM), and RLN resection. According to receiver operating characteristic (ROC) curve analyses, a cut-off of tumor size > 1.7 cm was identified as the most sensitive and specific predictor of RLN with multiple involvements or LNM invasion. Univariate and multivariate analyses revealed that central lymph node metastasis (CLNM) and RLN invasion by LNM can serve as independent risk factors for LLNM (p = 0.006 and p < 0.001, respectively).

CONCLUSION

Our results indicate that recurrence was comparable in patients with solitary and multiple RLN involvements. Multiple RLN involvement was associated with pathological features such as larger tumors, RLN resection, and LLNM. The presence of LNM invading RLN and multiple nerve involvement increases the risk of intraoperative RLN resection. A higher risk of multiple invasion or LNM invasion should be considered when tumor size > 1.7 cm. The presence of CLNM and RLN invaded by LNM were independent predictors for LLNM, which could aid surgeons in deciding on lateral lymph node dissection.

Shaving Papillary Thyroid Carcinoma Involving Functioning Recurrent Laryngeal Nerve: Safety of Incomplete Tumor Resection and Nerve Sparing

BACKGROUND

Whether to sacrifice or spare the recurrent laryngeal nerve (RLN) when papillary thyroid carcinoma (PTC) involves a functioning RLN remains controversial. Oncological outcomes after shaving PTC with gross remnant on the RLN have been rarely reported. The objective of this study was to evaluate the oncological outcomes of patients who underwent shaving of a PTC from the RLN, leaving a gross residual tumor with the intent of vocal function preservation.

METHODS

A retrospective, cohort study was conducted in 47 patients who were determined to have PTC invasion of the RLN via intraoperative inspection and underwent tumor shaving with macroscopic remnant (R2 resection) less than 1 cm in length and 4 mm in thickness. Median follow-up period was 93 (range, 60-215) months. The primary endpoint was the recurrence-free survival and the progression-free survival. Secondary endpoints were biochemical outcomes (serum thyroglobulin) and vocal cord function.

RESULTS

Of the 47 patients, five (10.6%) patients showed recurrence (central neck, 3; lateral neck, 2) without death or distant metastasis. The RLN was resected along with the tumor in one (2.1%) patient who presented with progression of the residual tumor. Postoperative temporary vocal cord paralysis occurred in six (12.8%) patients without permanent cases. The final nonstimulated serum thyroglobulin was 0.7 ± 1.8 ng/ml.

CONCLUSIONS

Shaving a tumor from a RLN with gross residual disease may be considered an alternative strategy to preserve vocal function when complete tumor resection with nerve preservation is impossible in patients with PTC invading a functioning RLN.

Incidence of Vocal Cord Paralysis in Medullary Thyroid Cancer

OBJECTIVE

Medullary thyroid cancer (MTC) is a neuroendocrine tumor that comprises 3-5% of all thyroid cancers in the United States. Vocal cord paralysis (VCP) may be due to involvement of the recurrent laryngeal nerve (RLN) preoperatively, or nerve sacrifice during surgery. The purpose of this study was to demonstrate the incidence of VCP in MTC and evaluate whether VCP has an impact on overall survival.

METHODS

This was a retrospective chart review of patients with MTC treated at Loyola University Medical Center from 2007 to 2021. Information on demographics, cancer diagnosis and treatment, laboratory data, and survival were collected.

RESULTS

A total of 79 patients were included in our study. 47 (59.5%) patients were female. The average age at the time of diagnosis was 51.3 years (SD 13.58). VCP was identified in 13 out of 79 (16.5%) patients. There were 71 patients with at least 1-year follow-up with median (Q1, Q3) years of 7.2 (3.9, 11.0). Those with VCP within 1 year had 7.2 (95% CI: 2.3, 22.7) times the risk of death compared to those without (p < 0.001).

CONCLUSION

MTC is a rare thyroid cancer, however, its incidence is on the rise. Our study suggests that the incidence of VCP in these patients appears to be higher than seen in other thyroid malignancies, and VCP is associated with a statistically significant negative impact on survival.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:890-894, 2023.

Guideline for the Surgical Management of Locally Invasive Differentiated Thyroid Cancer From the Korean Society of Head and Neck Surgery

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.

A large-scale study of patients with preoperative vocal cord paralysis associated with thyroid disease and related clinicopathological features

BACKGROUND

The performance of thyroidectomies has been increasing over the last decade due to the growing prevalence of thyroid diseases. The purpose of this study was to investigate the clinical significance of preoperative vocal cord paralysis (VCP) associated with thyroid disease and other incidences of malignant or benign lesions, as well as different thyroid pathological features. Additionally, the epidemiological changes of thyroid diseases with preoperative VCP were investigated.

METHODS

Ninety-nine out of 12,530 patients with preoperative VCP who had undergone thyroid surgery for various diseases in the Zhejiang Cancer Hospital from January 2007 to December 2015 were identified. Their clinicopathological data was recorded and case distributions from different years and intraoperative recurrent laryngeal nerve statuses were retrospectively analyzed.

RESULTS

The incidence of preoperative VCP in 2007 was reported to be 1.53% (9/590) and had decreased to 0.53% (12/2,247) by 2015 (P < 0.05). Among the 99 patients with preoperative VCP, 81 had malignancies (81.82%), while 18 (18.18%) had benign thyroid diseases. The incidences of preoperative VCP in malignant and benign diseases were 1.13% (81/7,159) and 0.35% (18/5,371), respectively (P < 0.05). There were only 5 (0.04%, 5/12,530) cases of papillary thyroid microcarcinoma with preoperative VCP. There was no statistical difference between the incidence of preoperative hoarseness in malignant 69.14% (56/81) and benign diseases 61.11% (11/18) with preoperative VCP.

CONCLUSIONS

The preoperative VCP incidence rate had gradually decreased with an increased proportion of papillary thyroid cancer. Preoperative voice symptoms do not necessarily suggest a malignancy. Selective rather than routine preoperative laryngoscopic examinations should be performed on papillary thyroid microcarcinomas. The probability of preoperative VCP in malignancy was significantly higher than in benign lesions.

Advanced Differentiated Thyroid Cancer: A Complex Condition Needing a Tailored Approach

Differentiated thyroid cancers (DTCs) are slow-growing malignant tumours, including papillary and follicular carcinomas. Overall, prognosis is good, although it tends to worsen when local invasion occurs with bulky cervical nodes, or in the case of distant metastases. Surgery represents the main treatment for DTCs. However, radical excision is challenging and significant morbidity and functional loss can follow the treatment of the more advanced forms. Literature on advanced thyroid tumours, both differentiated and undifferentiated, does not provide clear and specific guidelines. This emerges the need for a tailored and multidisciplinary approach. In the present study, we report our single-centre experience of 111 advanced (local, regional, and distant) DTCs, investigating the rate of radical excision, peri-procedural and post-procedural complications, quality of life, persistence, recurrence rates, and survival rates. Results are critically appraised and compared to the existing published evidence review.

Pathological Analysis of Encased Resected Recurrent Nerves in Locally Invasive Thyroid Cancer

Simple Summary

Thyroid cancer encasing the recurrent nerve is rare, and the decision to resect or preserve the nerve is multifactorial. The aim of this retrospective study was to evaluate the rate of actual invasion of the nerve beyond the nerve sheath in cancers encasing the nerve. Fifty-two patients were included: 7 cases of medullary thyroid carcinoma, 8 papillary thyroid carcinomas in children and 37 follicular derived cancers in adults. Tumor-related vocal fold paralysis was present in 30% of cases. The nerve was invaded in 82% of follicular cell-derived tumors, 88% of pediatric cases, and 100% of medullary carcinomas. Only agressive histology was a risk factor for nerve invasion. Vocal fold paralysis was not predictive. To our knowledge, this is one of the largest series with pathologic analysis of resected recurrent nerves, showing a high rate of nerve invasion in these rare cases of cancer encasing the reucrrent nerve.

Abstract

Objective: Thyroid cancer encasing the recurrent nerve is rare, and the decision to resect or preserve the nerve is multifactorial. The objective of this study was to histopathologically analyze resected encased nerves to assess the rate of nerve invasion and risk factors. Materials and Methods: A retrospective study was carried out on consecutive patients with resection of the recurrent nerve for primary or recurrent follicular cell-derived or medullary thyroid carcinoma from 2005 to 2020. Demographics, pathology, locoregional invasion, metastases, recurrences and survival were analyzed. Slides were reviewed blindly by two specialized pathologists (AAG, RC) for diagnosis of invasion deep to the epineurium. Results: Fifty-two patients were included: 25 females; average age, 55 (range 8–87). In total, 87% percent (45/52) were follicular cell-derived with 17/45 (37.8%) aggressive variants; 13% (7/52) were medullary carcinoma. Preoperative vocal fold (VF) paralysis was present in 16/52 (30.7%). Pathologically, the nerve was invaded in 44/52 cases (85%): 82% of follicular cell-derived tumors (37/45), 88% of pediatric cases, and 100% of medullary carcinomas (7/7). Nerve invasion was observed in 11/16 (69%) with preoperative VF paralysis and 33/36 (92%) with normal VF function. Only aggressive histology was correlated with nerve invasion in follicular cell-derived tumors (p = 0.019). Conclusions: The encased nerves were pathologically invaded in 82% of follicular cell-derived tumors and in 100% of medullary carcinomas. Nerve invasion was statistically correlated with aggressive histopathological subtypes and was observed in the absence of VF paralysis in 92% of cases.

Thyroidectomy for Papillary Thyroid Carcinoma

Papillary thyroid carcinoma is the most common endocrine malignancy and accounts for the overwhelming majority of thyroid carcinoma. This recent dramatic increase in incidence is almost exclusively attributed to the incidental detection of small papillary thyroid carcinoma or microcarcinoma. Surgical management of thyroid carcinoma has been evolving to avoid overtreating patients by adopting the appropriate risk-based approach including the recommendation of hemithyroidectomy for low-risk carcinoma, the avoidance of routine prophylactic central nodal dissections, a higher threshold in using postoperative radioiodine ablation after total thyroidectomy, and the active observation or surveillance of papillary microcarcinoma as a viable alternative option instead of immediate surgical treatment.

Optimal Management of the Unilateral Recurrent Laryngeal Nerve Involvement in Patients with Thyroid Cancer

Simple Summary

Recurrent laryngeal nerve (RLN) is the second most common structure invaded by primary or metastatic thyroid cancer. However, little is known about the optimal procedure for maintaining vocal function in patients with unilateral RLN involvement in thyroid cancer. This study aimed to evaluate various parameters of vocal function to establish the optimal management of thyroid cancer patients with unilateral RLN involvement. Based on our findings, we propose that for optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible. These findings may help improve management of RLN involvement in patients with thyroid cancer and ensure vocal function preservation.

Abstract

We aimed to determine the optimal management of recurrent laryngeal nerve (RLN) involvement in thyroid cancer. We enrolled 80 patients with unilateral RLN involvement in thyroid cancer between 2000 and 2016. Eleven patients with preoperatively functional vocal folds (VFs) underwent sharp tumor resection to preserve the RLN (shaving group). Thirty-three patients underwent RLN reconstruction with RLN resection (reconstruction group). We divided the reconstruction group into two subgroups based on preoperative VF mobility (normal-reconstruction and paralyzed-reconstruction subgroups). In the cases where RLN reconstruction was difficult, phonosurgeries including arytenoid adduction (AA), with or without thyroplasty type I, or nerve muscle pedicle implantation with AA were performed later (phonosurgery group). We evaluated and compared vocal function among the evaluated periods and different groups. Postoperative vocal function in the shaving and normal-reconstruction subgroups was favorable. There were no significant differences between the two groups. In the paralyzed-reconstruction and phonosurgery groups, postoperative vocal function was significantly improved, and vocal function in the paralyzed-reconstruction subgroup was significantly better than that in the phonosurgery group. For optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible.

Clinical outcomes of T4a papillary thyroid cancer with recurrent laryngeal nerve involvement: a retrospective analysis

Preoperative vocal cord palsy (VCP) may indicate locally invasive papillary thyroid cancer (PTC); using this relationship, we evaluated the clinical outcomes and risk factors for recurrence in post-thyroidectomy T4a PTC patients with recurrent laryngeal nerve (RLN) involvement. We retrospectively investigated thyroidectomy patients, recorded their clinical factors, recurrence rate, and pathological findings, and analysed the relationship between recurrence rate and clinical factors. Of 72 patients, 37 (51%) had preoperative VCP and 35 (49%) had normal preoperative vocal cord movement with confirmed intraoperative RLN invasion. Tracheal and esophageal invasion was observed in 13 (18%) and 15 (21%) patients, respectively. Thyroid cancer recurred in 18 (25%) patients over 58 months, resulting in 2 (3%) deaths. Recurrence was not associated with surgical extent, organ invasion, enlarged tumour size, or lymph node infiltration (p > 0.05). The recurrence rate was significantly higher in patients with positive resection margins (p < 0.05). T4a PTC patients with RLN involvement showed a poor prognosis. The recurrence rate was not affected by preoperative VCP, intraoperative detection of RLN invasion, nerve resection, nerve preservation by shaving, lymph node metastasis, or tracheal or esophageal invasion. The most important prognostic factor for recurrence was a positive resection margin.

Novel surgical methods for reconstruction of the recurrent laryngeal nerve: Microscope-guided partial layer resection and intralaryngeal reconstruction of the recurrent laryngeal nerve

BACKGROUND

The optimal strategy for surgical management of papillary thyroid carcinoma invasion of the recurrent laryngeal nerve remains controversial. Our aim was to evaluate the efficacy of 2 surgical methods and provide detailed descriptions of microscope-guided partial layer resection and intralaryngeal reconstruction of the recurrent laryngeal nerve.

METHODS

This retrospective study enrolled 85 patients with papillary thyroid carcinoma who underwent initial surgical excision for invasion of the recurrent laryngeal nerve. Twenty-seven patients (28 recurrent laryngeal nerve sites) underwent partial layer resection, and 11 patients (11 recurrent laryngeal nerve sites) underwent intralaryngeal reconstruction of the recurrent laryngeal nerve. The remaining patients underwent either only resection or resection with immediate reconstruction of the recurrent laryngeal nerve. Pre and postoperative phonetic function and rates of locoregional recurrence were extracted from medical charts for analysis.

RESULTS

Isolated locoregional recurrence specific to the aerodigestive tract was identified in 1 patient (3.7%) in the partial layer resection group and 1 patient (9.1%) in the intralaryngeal reconstruction group. Seventy-five percent of patients in the partial layer resection group recovered or had preserved vocal cord function, and the mean maximum phonation time of the patients with postoperative complete vocal cord palsy was 15.3 seconds. The mean maximum phonation time of the patients, excluding 4 patients with permanent stoma in the intralaryngeal reconstruction group, was 22.3 seconds. The mean maximum phonation time of either group was longer than that of patients with recurrent laryngeal nerve resection only and comparable with that of patients with recurrent laryngeal nerve resection and immediate reconstruction.

CONCLUSION

Patients who underwent either partial layer resection or intralaryngeal reconstruction had low rates of locoregional recurrence specific to the aerodigestive tract and good postoperative functional outcomes.

The revised clinical practice guidelines on the management of thyroid tumors by the Japan Associations of Endocrine Surgeons: Core questions and recommendations for treatments of thyroid cancer

The Japan Associations of Endocrine Surgeons has developed the revised version of the Clinical Practice Guidelines for Thyroid Tumors. This article describes the guidelines translated into English for the 35 clinical questions relevant to the therapeutic management of thyroid cancers. The objective of the guidelines is to improve health-related outcomes in patients with thyroid tumors by enabling users to make their practice evidence-based and by minimizing any variations in clinical practice due to gaps in evidential knowledge among physicians. The guidelines give representative flow-charts on the management of papillary, follicular, medullary, and anaplastic thyroid carcinoma, along with recommendations for clinical questions by presenting evidence on the relevant outcomes including benefits, risks, and health conditions from patients' perspective. Therapeutic actions were recommended or not recommended either strongly (◎◎◎ or XXX) based on good evidence (😊)/good expert consensus (+++), or weakly (◎, ◎◎ or X, XX) based on poor evidence (😣)/poor expert consensus (+ or ++). Only 10 of the 51 recommendations given in the guidelines were supported by good evidence, whereas 35 were supported by good expert consensus. While implementing the current guidelines would be of help to achieve the objective, we need further clinical research to make our shared decision making to be more evidence-based.

An impact of microscopic positive margin on incomplete response after I-131 treatment in differentiated thyroid cancer

OBJECTIVE

To find an impact of microscopic positive margin on incomplete response after initial I-131 therapy in differentiated thyroid cancer.

METHODS

We retrospectively recruited patients with differentiated thyroid cancer who underwent total thyroidectomy and received the first dose of radioiodine during January 2014-February 2018. Patients with grossly incomplete tumor resection or distant metastasis at the time of radioiodine therapy were excluded. Thyroid specimens were re-evaluated by one pathologist who was blinded to clinical information to determine microscopic margin status. Treatment response was evaluated at 6-12 months after therapy and was categorized according to the 2015 American Thyroid Association guidelines. Univariable and multivariable analyses were used to find an association between microscopic positive margin and incomplete response.

RESULTS

A total of 101 patients (78 females; mean age 50.3 years) were enrolled. Ninety-four patients (93.1%) had papillary thyroid carcinoma. Microscopic positive margin was found in 27 patients (26.7%). After the median follow-up time of 10.3 months, incomplete response was observed in 13 patients (48.5%) and 17 patients (23.0%) with positive and negative margins, respectively. Multivariable analysis showed a significant association between microscopic positive margin and incomplete response after adjusting for tumor size, ETE, and cervical lymph node metastasis with adjusted odds ratio of 3.04 (95% CI 1.05-8.75, p value = 0.04). Moreover, after adding pre-ablative Tg as a covariate in 69 patients with negative TgAb, positive margin had a trend toward being associated with incomplete response with adjusted odds ratio of 3.43 (95% CI 0.73-16.07, p value = 0.118).

CONCLUSIONS

Microscopic positive margin was found to be significantly associated with incomplete response after I-131 therapy in patients with differentiated thyroid cancer after adjusting for tumor size, ETE, and cervical lymph node metastasis and also had a trend toward being associated with incomplete response after adjusting for pre-ablative Tg.

Immediate Ansa Cervicalis-to-Recurrent Laryngeal Nerve Anastomosis for the Management of Recurrent Laryngeal Nerve Infiltration by a Differentiated Thyroid Carcinoma

OBJECTIVES

The optimal surgical approach to treat recurrent laryngeal nerve (RLN) infiltration by differentiated thyroid cancer (DTC) remains a subject of debate. This study explored the feasibility and efficiency of immediate ansa cervicalis nerve (ACN)-to-RLN anastomosis for the management of RLN infiltration by DTC.

MATERIAL AND METHODS

Fifty-three patients who underwent immediate ACN-to-RLN anastomosis during DTC extirpation were enrolled in the present study. Thirty-seven cases presented with unilateral vocal cord paralysis before the operation (Group A), and another 16 patients presented with normal vocal cord mobility preoperatively (Group B). Multidimensional assessments, videostroboscopy, voice assessment, and laryngeal electromyography (LEMG) were performed preoperatively and postoperatively.

RESULTS

All videostroboscopy, voice assessment and LEMG parameters in Group A deteriorated 1 month after the operation and improved 1 year after the operation compared with preoperative data. In Group B, all parameters 1 year after the operation improved significantly compared with the corresponding parameters 1 month after the operation. LEMG in Group A and B provided substantial evidence for the maturation of neural regeneration from ACN and demonstrated that the laryngeal muscles were reinnervated successfully by this procedure.

CONCLUSIONS

If the RLN is infiltrated by DTC, immediate ACN-to-RLN anastomosis during complete excision of DTC could restore satisfactory phonatory function and does not compromise oncological radicality.

Modern surgery for advanced thyroid cancer: a tailored approach

Surgical treatment of advanced thyroid malignancy can be morbid, compromising normal functions of the upper aerodigestive tract. There is a paucity of guidelines dedicated to the management of advanced disease. In fact, there is not even a uniform definition for advanced thyroid cancer currently. The presence of local invasion, bulky cervical nodes, distant metastases or recurrent disease should prompt careful preoperative evaluation and planning. Surgical strategy should evolve from multidisciplinary discussion that integrates individual disease characteristics and patient preference. Intraoperative neuromonitoring has important applications in surgery for advanced disease and should be used to guide surgical strategy and intraoperative decision-making. Recent paradigm shifts, including staged surgery and use of neoadjuvant targeted therapy hold potential for decreasing surgical morbidity and improving clinical outcomes. Modern surgical planning provides optimal treatment for each patient through a tailored approach based on exact extent and type of disease as well as incorporating appreciation of surgical complications, patient preferences and intraoperative findings.

Surgical management of the compromised recurrent laryngeal nerve in thyroid cancer

Surgical management of thyroid cancer requires careful consideration of the recurrent laryngeal nerve and its impact on glottic function. Management of the compromised recurrent laryngeal nerve is a complex task, requiring synthesis of multiple elements. The surgeon must have an appreciation for preoperative recurrent laryngeal nerve function, intraoperative anatomic and electromyographic information, disease characteristics, and relevant patient factors. Preoperative clinical evaluation including preoperative laryngoscopy and assessment of recurrent laryngeal nerve risk is essential to formulating a surgical plan and providing appropriate patient counseling. Intraoperative neuromonitoring information has significant implications for surgical management of the injured or invaded recurrent laryngeal nerve and informs strategy with respect to staging of bilateral surgery. Disease characteristics and patient-related factors, including patient preference, must be considered with intraoperative decision-making. Multidisciplinary discussion and patient communication are essential for effective management and successful surgical outcome.

International neuromonitoring study group guidelines 2018: Part II: Optimal recurrent laryngeal nerve management for invasive thyroid cancer-incorporation of surgical, laryngeal, and neural electrophysiologic data

The purpose of this publication was to inform surgeons as to the modern state-of-the-art evidence-based guidelines for management of the recurrent laryngeal nerve invaded by malignancy through blending the domains of 1) surgical intraoperative information, 2) preoperative glottic function, and 3) intraoperative real-time electrophysiologic information. These guidelines generated by the International Neural Monitoring Study Group (INMSG) are envisioned to assist the clinical decision-making process involved in recurrent laryngeal nerve management during thyroid surgery by incorporating the important information domains of not only gross surgical findings but also intraoperative recurrent laryngeal nerve functional status and preoperative laryngoscopy findings. These guidelines are presented mainly through algorithmic workflow diagrams for convenience and the ease of application. These guidelines are published in conjunction with the INMSG Guidelines Part I: Staging Bilateral Thyroid Surgery With Monitoring Loss of Signal. Level of Evidence: 5 Laryngoscope, 128:S18-S27, 2018.

MicroRNA-125b Interacts with Foxp3 to Induce Autophagy in Thyroid Cancer

Thyroid cancer is rapidly increasing in incidence worldwide. Although most thyroid cancer can be cured with surgery, radioactive iodine, and/or chemotherapy, thyroid cancers still recur and may become chemoresistant. Autophagy is a complex self-degradative process that plays a dual role in cancer development and progression. In this study, we found that miR-125b was downregulated in tissue samples of thyroid cancer as well as in thyroid cancer cell lines, and the expression of Foxp3 was upregulated. Further, we demonstrated that miR-125b could directly act on Foxp3 by binding to its 3' UTR and inhibit the expression of Foxp3. A negative relationship between miR-125b and Foxp3 was thus revealed. Overexpression of miR-125b markedly sensitized thyroid cancer cells to cisplatin treatment by inducing autophagy through an Atg7 pathway in vitro and in vivo. Taken together, our findings demonstrate a novel mechanism by which miR-125b has the potential to negatively regulate Foxp3 to promote autophagy and enhance the efficacy of cisplatin in thyroid cancer. miR-125 may be of therapeutic significance in thyroid cancer.

Aggressive differentiated thyroid cancer

Differentiated thyroid cancer is characteristically associated with an innocuous clinical course, but a minority of cases may manifest surprisingly aggressive behaviour. Such aggressive DTC are directly responsible for the majority of thyroid cancer related deaths. Moreover, they contribute indirectly to increased DTC-related morbidity, because our inability to differentiate these tumours from innocuous DTC at an early stage fuels a significant degree of DTC overtreatment around the globe. In the present paper we describe how improved understanding of the clinicopathological thyroid tumour progression model and optimization of clinical staging systems continues to improve our ability to diagnose and treat aggressive DTC. Early recognition of aggressive DTC allows instillation of an aggressive management strategy which is based upon surgical-oncologic completeness, and minimization of treatment-related sequelae through continued development of reconstructive options and focussed delivery of adjuvant treatments.

Bilateral vocal cord palsy after total thyroidectomy-A new treatment-Case reports

INTRODUCTION

Dyspnea due to bilateral vocal cord palsy after total thyroidectomy (BVCPATT) is a life-threatening complication; nevertheless, we try to avoid tracheotomy.

METHODS

Using normalized glottal area (NGA), we retrospectively studied 14 patients with BVCPATT. Nine patients without dyspnea were treated conservatively, while five with dyspnea received immediate bilevel positive air-way pressure (BiPAP) treatment. Both right and left recurrent nerves were grossly intact during surgery.

RESULTS

The mean NGA during inspiration of five patients with dyspnea was less than that of nine patients without (6.21±1.57 (mean±standard deviation) vs. 20.5±9.5; p=0.001). The mean age of patients with dyspnea was more than that of patients without (61.6±15.6 vs. 38±10.2; p=0.007). Five patients with dyspnea that occurred at 0-8days post operation recovered within 3-17days after BiPAP.

CONCLUSION

Dyspnea occurred in patients with BVCPATT who were relatively older. The mean NGA during inspiration in patients with dyspnea was less than that in patients without. BiPAP might be a new treatment for dyspnea.

Does microscopically involved margin increase disease recurrence after curative surgery in papillary thyroid carcinoma?

BACKGROUND

The prognostic significance of microscopically involved margin in papillary thyroid carcinoma (PTC) following curative surgery remains unclear. We aimed to evaluate the impact of an involved margin and its location (anterior vs. posterior) on disease recurrence.

METHODS

Of the 638 eligible patients, 538 (85.9%) did not have an involved margin (group I) while 100 (14.1%) did (group II). The latter group was further classified according to its location relative to the surface of the thyroid gland (anterior or posterior). A multivariate analysis was conducted to identify independent factors for recurrence risk.

RESULTS

After a mean of 130.1 ± 93.5 months, 22 patients had disease recurrence. The 10-year disease-free survival (DFS) was significantly worse in group II (95.0% vs. 97.0%, P = 0.011). After adjusting other significant factors, involved margin was not an independent risk factor for disease recurrence (P = 0.358). Compared to a negative margin, an anterior involved margin did not pose increased recurrence risk (HR = 1.21, 95%CI = 0.93-500.00, P = 0.368), whereas a posterior involved margin had almost 23 times higher recurrence risk (HR = 22.95; 95%CI = 4.33-121.70, P < 0.001).

CONCLUSIONS

Overall, a microscopically involved margin was not an independent factor for DFS. However, although an anterior involved margin itself did not increase disease recurrence, a posterior involved margin did. J. Surg. Oncol. 2016;113:635-639. © 2016 Wiley Periodicals, Inc.

Treatment Outcomes and Risk Factors for Recurrence After Definitive Surgery of Locally Invasive Well-Differentiated Papillary Thyroid Carcinoma

BACKGROUND

Papillary thyroid carcinoma (PTC) is generally an indolent tumor that has a favorable prognosis. However, locally invasive PTC can recur after treatment, and its optimal treatment is still controversial. This study aimed to evaluate treatment outcomes and identify risk factors for recurrence and survival in patients with locally invasive PTC.

MATERIALS AND METHODS

All consecutive patients who underwent definitive surgery and radioactive iodine therapy for non-distant metastatic invasive PTC were included. Clinical factors, operative and pathological findings, surgical morbidity, and recurrences were recorded. Univariate and multivariate Cox proportional hazard models served to identify factors associated with recurrence-free survival (RFS) and overall survival.

RESULTS

Of the 96 patients, 74 (77%), 52 (55%), 4 (4%), and 14 (15%) had invasion to the recurrent laryngeal nerve (RLN), trachea, larynx, and esophagus, respectively; 39 (41%) had preoperative vocal cord paresis or paralysis; and 24 (25%) developed recurrence during follow-up (median 77 months). The patients with single and multiple organ invasion did not differ significantly in terms of recurrence-free or overall survival (p > 0.05). The patients with and without recurrences did not differ in terms of surgical extent and involving nerve preservation. Multivariate analysis showed that high (≥1 ng/mL) post-ablation stimulated serum thyroglobulin concentration was an independent predictor of poor RFS (p = 0.013).

CONCLUSION

Disease extent, surgical extent, and involving nerve preservation did not associate with recurrence or overall survival outcomes. The post-ablation stimulated thyroglobulin level may be an independent predictor for recurrence. Careful follow-up of patients with this risk factor is recommended.

Papillary thyroid carcinoma with exclusive involvement of a functioning recurrent laryngeal nerve may be treated with shaving technique

OBJECTIVES

We sought to validate the feasibility of preserving a functioning recurrent laryngeal nerve (RLN) invaded by papillary thyroid carcinoma (PTC) using a shaving technique followed by high-dose radioactive iodine (RAI) therapy.

METHODS

A retrospective review of 34 patients with locally invasive PTC who had exclusive tumor involvement of a functioning RLN was performed. All patients underwent total thyroidectomy and high-dose RAI therapy. A shaving technique was conducted with the goal of leaving the smallest amount of residual tumor as possible while attempting to preserve nerve function. Clinicopathologic factors and oncologic outcomes of the patients with resected RLN (group A, n = 14) and preserved RLN (group B, n = 20) were compared.

RESULTS

The two groups showed no differences in clinicopathologic factors or follow-up period. Mean dose of radioiodine therapy was 245.0 ± 140.3 mCi (range 100-540 mCi). Permanent postoperative vocal cord paralysis after RLN shaving occurred in two patients of group B (10%). Only one patient (5%) in group B had local recurrence at the thyroid bed where the residual tumor was located. The overall recurrence rate was 35.7% (5/14) and 20.0% (4/20) in groups A and B, respectively showing no significant difference (p = 0.525). There were no cases of death due to PTC during the median follow-up of 75 months (range 36-159 months).

CONCLUSIONS

Patients with locally invasive PTC with exclusive involvement of a functioning RLN may be treated by nerve shaving followed by treatment of the macroscopic residual tumor with high-dose RAI therapy.

Impact of lymph node metastases with recurrent laryngeal nerve invasion on patients with papillary thyroid carcinoma

BACKGROUND

Although rare, invasion by papillary thyroid carcinoma (PTC) of the upper aerodigestive tract significantly affects patients' prognosis and quality of life. Within the central compartment, the recurrent laryngeal nerve (RLN) is most frequently invaded by lymph node metastases (LNM). However, such an invasion has not been described in the literature, although reports on RLN invasion by primary tumors have been published. The present study aimed to characterize LNM with RLN invasion in patients with PTC.

METHODS

The participants of this retrospective investigation were selected from 629 PTC patients who received initial surgical treatment at our institution between January 1981 and December 2012. They included 38 (6%) patients with 40 cases of RLN invasion by LNM (LNM invasion group) and 112 (17.8%) patients with 117 cases of RLN invasion by the primary tumor (primary invasion group).

RESULTS

In the LNM invasion group, 70% of the RLN invasion cases occurred on the right side, whereas those in the primary invasion group were almost equally distributed. RLN invasion caused vocal cord paralysis, affecting 13 nerves (32.5%) in the LNM invasion group and 68 nerves (58%) in the primary invasion group. Significant differences in laterality and preoperative vocal cord paralysis were observed between the two groups. In the LNM invasion group, the longest diameter of metastatic lymph nodes (mean±standard deviation) of patients with RLN paralysis was 21±8 mm, whereas it was significantly different at 14±7 mm in those without RLN paralysis.

CONCLUSIONS

Our results indicate that most patients with RLN invasion by LNM did not experience preoperative vocal cord paralysis. LNM invasion of the RLN (70%) more often occurred on the right side as expected given the complexity and three-dimensional anatomy of the RLN in the right paratracheal region compared to the left. RLN invasion by LNM should be considered if preoperative paratracheal nodal disease, especially when bulky, is noted in the right paratracheal region.

A new strategy for the surgical management of RLN infiltrated by well-differentiated thyroid carcinoma

Well-differentiated thyroid carcinoma (WDTC) represents the most common endocrine malignancy. Despite excellent prognoses exceeding 90% in 10-year follow-up, there are clinically controversial issues. One of these is extrathyroidal tumour extension invading recurrent laryngeal nerve (RLN). The spread outside of the thyroid parenchyma and invasion to the surrounding structures, classified as always T4a, are the most important negative prognostic factor for the WDTC. Conversely, resection of the RLN leads to vocal cord paralysis with hoarseness, possible swallowing problems, and finally decreased quality of life. We propose a new algorithm for intraoperative management based on the MACIS classification, which would allow swift status evaluation pre/intraoperatively and consider a possibility to preserve the infiltrated RLN without compromising an oncological radicality. In the case of a preoperative vocal cord paralysis (VCP) and confirmation of the invasive carcinoma, a resection of the RLN and the nerve graft reconstruction are indicated. Preoperatively, unaffected vocal cord movement and intraoperatively detected RLN infiltration by the invasive WDTC require an individual assessment of the oncological risk by the proposed algorithm. Preservation of the infiltrated RLN is oncologically acceptable only in specific groups of patients of a younger age with a minor size of primary tumour.