Clinical outcome of different modes of resection in papillary thyroid carcinomas with laryngotracheal invasion

Comparative long-term outcomes of airway resection and functional reconstruction for papillary thyroid cancer

INTRODUCTION

The surgical management of patients diagnosed with papillary thyroid carcinoma (PTC) and tracheal invasion has been a subject of ongoing discussion, particularly regarding the approach to tracheal functional reconstruction. The objective of this study was to examine the surgical technique and prognosis of PTC patients with tracheal invasion.

MATERIALS AND METHODS

This study employed both univariate and multivariate Cox proportional hazard models to determine predictive factors that affect the progression-free survival (PFS) of PTC patients with tracheal invasion. Cox regression analysis was conducted by using R software version 4.3.1.

RESULTS

In our study, we included 247 patients with T4a PTC. Among them, 146 patients (59.1 %) were classified as Shin I, 57 patients (23.1 %) as Shin II-III, and 44 patients (17.8 %) as Shin IV. Patients in the Shin I group underwent shaving of the tumours in the airway. The preferred surgical methods in the Shin II, III and IV groups were window resection (66.7 %), sleeve resection (34.8 %) and partial tracheal resection and skin fistula (61.8 %), respectively. Multivariate analysis demonstrated that neither tracheal surgery nor reconstruction procedures had an impact on PFS in T4a PTC patients with tracheal invasion. The 5-year DSS rate for patients receiving radioiodine (RAI) therapy was 87.3 % (p = 0.033).

CONCLUSION

This study confirmed that tracheal surgery and reconstruction methods had no impact on PFS in T4a PTC patients with tracheal invasion in different Shin groups. Furthermore, RAI therapy has the potential to increase the survival rate of patients with preoperative distant metastasis of T4a PTC.

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.

Clinical significance of extrathyroidal extension to major vessels in papillary thyroid carcinoma

PURPOSE

Gross extrathyroidal extension (gETE) into major vessel is considered the most advanced stage of the locally advanced papillary thyroid cancer (PTC). Surgical intervention may not benefit some patients at this disease stage or even result in intraoperative death due to massive hemorrhage; however, it is still considered an effective strategy for most cases. The lack of description for this challenging invasion in PTC warrants detailed characterization of its pattern, risk factors, optimal surgical method, and prognostic value.

METHODS

In total, 3127 patients diagnosed as having PTC were enrolled and categorized into two the following groups, namely the major vessel invasion (MVI) group (n = 30) and the control group (n = 3097). Data regarding clinicopathological and demographic characteristics, vascular invasion sites, postoperative complications, locoregional recurrence, distant metastasis, and surgical strategies were collected. Predictive disease-free survival (DFS) was also compared between the two groups.

RESULTS

MVI was independently associated with invasion of the esophageal extension, age < 55 years, tumor size > 1 cm, lateral lymph node metastasis, and distant metastasis (P = 0.00; P = 0.01; 0.05; P = 0.00; P = 0.00, respectively). The difference in the predictive DFS between the two groups was significant (P = 0.00), and the difference remained significant even in patients with ETE when compared with patients without ETE (P = 0.00). Additionally, predictive DFS did not differ significantly between patients who received vessel repairment and those who received vessel resection (P = 0.28).

CONCLUSIONS

This study first characterized the gross MVI pattern exhibited by PTC and the risk factors for MVI. Additionally, it demonstrated the DFS of patients with PTC. Extensive gross MVI significantly worsened the biological characteristics of PTC. Regardless of the high risk and difficulty of the operation, patients still benefited from the surgical intervention, and vessel repairment may be the optimal surgical strategy.

Tracheal and Cricotracheal Resection With End-to-End Anastomosis for Locally Advanced Thyroid Cancer: A Systematic Review of the Literature on 656 Patients

Airway involvement by advanced thyroid carcinoma (TC) constitutes a negative prognosticator, besides being a critical clinical issue since it represents one of the most frequent causes of death in locally advanced disease. It is generally agreed that, for appropriate laryngo-tracheal patterns of invasion, (crico-)tracheal resection and primary anastomosis [(C)TRA] is the preferred surgical technique in this clinical scenario. However, the results of long-term outcomes of (C)TRA are scarce in the literature, due to the rarity of such cases. The relative paucity of data prompts careful review of the available relevant series in order to critically evaluate this surgical technique from the oncologic and functional points of view. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement on the PubMed, Scopus, and Web of Science databases. English-language surgical series published between January 1985 and August 2021, reporting data on ≥5 patients treated for TC infiltrating the airway by (C)TRA were included. Oncologic outcomes, mortality, complications, and tracheotomy-dependency rates were assessed. Pooled proportion estimates were elaborated for each end-point. Thirty-seven studies were included, encompassing a total of 656 patients. Pooled risk of perioperative mortality was 2.0%. Surgical complications were reported in 27.0% of patients, with uni- or bilateral recurrent laryngeal nerve palsy being the most common. Permanent tracheotomy was required in 4.0% of patients. Oncologic outcomes varied among different series with 5- and 10-year overall survival rates ranging from 61% to 100% and 42.1% to 78.1%, respectively. Five- and 10-year disease specific survival rates ranged from 75.8% to 90% and 54.5% to 62.9%, respectively. Therefore, locally advanced TC with airway invasion treated with (C)TRA provides acceptable oncologic outcomes associated with a low permanent tracheotomy rate. The reported incidence of complications, however, indicates the need for judicious patient selection, meticulous surgical technique, and careful postoperative management.

Surgical Management of Tracheal Invasion by Well-Differentiated Thyroid Cancer

Simple Summary

Tracheal invasion is a poor prognostic factor in well-differentiated thyroid cancer. Appropriate resection can improve the prognosis and maintain the patient’s quality of life. Shaving resection for superficial tracheal invasion is minimally invasive because it does not involve the tracheal lumen, despite the problematic risk of local recurrence. Window resection for tracheal mucosal and luminal invasion provides good tumor control and does not cause postoperative airway obstruction; however, the need for surgical closure of the tracheocutaneous fistula is a disadvantage of this method. Circumferential (sleeve) resection and end-to-end anastomosis are highly curative, but the risk of fatal complications, such as anastomosis dehiscence, is a concern.

Abstract

Well-differentiated thyroid carcinoma (WDTC) is a slow-growing cancer with a good prognosis, but may show extraglandular progression involving the invasion of tumor-adjacent tissues, such as the trachea, esophagus, and recurrent laryngeal nerve. Tracheal invasion by WDTC is infrequent. Since this condition is rare, relevant high-level evidence about it is lacking. Tracheal invasion by a WDTC has a negative impact on survival, with intraluminal tumor development constituting a worse prognostic factor than superficial tracheal invasion. In WDTC, curative resection is often feasible with a small safety margin, and complete resection can ensure a good prognosis. Despite its resectability, accurate knowledge of the tracheal and peritracheal anatomy and proper selection of surgical techniques are essential for complete resection. However, there is no standard guideline on surgical indications and the recommended procedure in trachea-invading WDTC. This review discusses the indications for radical resection and the three currently available major resection methods: shaving, window resection, and sleeve resection with end-to-end anastomosis. The review shows that the decision for radical resection should be based on the patient’s general condition, tumor status, expected survival duration, and the treating facility’s strengths and weaknesses.

Postoperative outcomes of free myocutaneous flap and pedicled myocutaneous flap for reconstruction in locally invasive thyroid carcinoma

Locally invasive thyroid carcinoma (TC) often involves trachea. In such patients, the trachea needs to be reconstructed after surgery. We discuss the postoperative outcome and complications after trachea reconstruction by free myocutaneous flap (FMF) and pedicled myocutaneous flap (PMF).From January 2009 to September 2019, the clinical data of 38 patients with TC were retrospectively analyzed. Demographics, pathologic results, neoplasm staging, surgical protocol, decannulation, subjective speech function, and complications were documented.A total of 38 patients were analyzed (22 FMFs and 16 PMFs). Of the 38 patients, there is a similar rate of decannulation (81.8% in FMF and 75% in PMF), subjective speech function and complications.The FMF reconstruction and the PMF reconstruction have a similar result in terms of postoperative outcome and complications.

Long-term outcomes of differentiated thyroid cancers with tracheal invasion: A 15-year experience

BACKGROUND

Tracheal invasion is reported to occur in approximately one-third of the patients of locally advanced thyroid cancers. There is a paucity of data in literature with regard to the long-term outcomes of thyroid cancers with tracheal invasion.

METHODS

A total of 37 patients from our tertiary care center underwent radical surgery for tracheal involvement for differentiated thyroid cancers between the years 2002 and 2016. The variables pertaining to the demographics, clinical presentation, imaging, operative details and histopathology reports were captured from the patient's case records and analyzed.

RESULTS

Among the 37 patients, there were 21 males and 16 females. Majority of the patients (56.8%) were >55 years of age. Surgery (tracheal resection) was performed in the primary setting in 29 patients, whereas it was performed in a recurrent setting in 8 patients. As per the Shin classification, 3 patients belonged to Shin stage 1, 3 to Shin stage 2, 16 patients to Shin stage 3 and 15 patients to Shin stage 4. There was no 30 day postoperative mortality in our cohort. The median follow-up of our cohort was 175 months. The 5-, 10-, and the 15-year overall survivals of the entire cohort were 81.7%, 47.8%, and 35.9%, respectively.

CONCLUSION

Our series shows favorable long-term oncological outcomes of selected patients of thyroid cancers with tracheal resection and adds to the limited long-term data available in literature.

Surgical treatment of locally advanced thyroid cancer

Operations in this area are demanding and require special experience in endocrine, thoracic and vascular surgery, an experienced anaesthesiologist, as well as the interdisciplinary cooperation with other medical specialists (nuclear medicine, oncology, radiology, otolaryngology). A reliable system of surgical guidelines has been developed from a few individual publications with special impact.

Simultaneous tracheal and esophageal reconstruction for thyroid cancer involving trachea and esophagus using a free bipaddled posterior tibial artery perforator flap

BACKGROUND

Simultaneous tracheal and esophageal reconstruction after tumor resection is a great challenge. Here we present an innovative operative technique to simultaneously reconstruct tracheal and esophageal defects, in which a free posterior tibial artery perforator flap was made into a free bipaddled flap to cover both tracheal and esophageal defects.

METHODS

A free bipaddled posterior tibial artery perforator flap was utilized to conduct simultaneous tracheal and esophageal reconstruction for a 72-year-old female patient with papillary thyroid carcinoma and massive trachea and esophagus invasion, who underwent radical resection.

RESULTS

Satisfactory breathing and swallowing functions were gained independent of nasal feeding and tracheotomy. Voice was still hoarse due to tumor invasion of left recurrent laryngeal nerve. During a period of 2-year follow-up, no sign of tumor recurrence was observed.

CONCLUSION

A free bipaddled posterior tibial artery perforator flap could be a decent choice for simultaneous reconstruction of large tracheal and esophageal defects.

Complications from tracheal resection for thyroid carcinoma

Thyroidectomy associated to en bloc tracheal resection with end-to-end anastomosis is the treatment of choice of thyroid tumor invading the tracheal wall and is associated with a good prognosis. However, the postoperative morbidity is not irrelevant. The present review aims to discuss the complications occurring after this aggressive surgical procedure. The search was performed using PubMed through an overarching for the following terms: "complication of tracheal resection [AND] invasive thyroid cancer". Postoperative complications rate after tracheal sleeve resection with end-to-end anastomosis for thyroid cancer invading tracheal wall range from 15% to 39%. Postoperative mortality is about 1.2%. The most common postoperative complications are: anastomotic dehiscence, airway stenosis, infections and bleeding. Tumor local recurrence can be considered a late on set complication. To conclude, in locally invasive thyroid cancer, en bloc resection of the thyroid with the tracheal segment interested by the tumor provides a good prognosis despite the non-negligible postoperative morbidity rate. Patients' selection and accurate surgical technique performing a tracheal tension-free anastomosis are mandatory to reduce postoperative morbidity and mortality.

Anastomosis in the absence of a suprahyoid release following circumferential sleeve resection is feasible in differentiated thyroid carcinoma patients with tracheal invasion

Invasion of the trachea is observed in ~6% of patients with differentiated thyroid carcinoma (DTC), and surgery is accepted as the treatment of choice. However, surgical procedures can be challenging and are associated with various risks. The authors of the present study performed a retrospective study of patients with DTC and tumor invasion of the trachea. Outcomes from patients that received circumferential sleeve resection (CSR) of the trachea followed by anastomosis in the absence of suprahyoid release (n=21; CSR group) and patients that underwent tangential resections [n=103; tangential ‘shave’ resection (TSR) group) were analyzed. In the CSR group, 4 to 8 tracheal rings were circumferentially resected. All patients underwent end-to-end anastomosis in the absence of suprahyoid release following CSR, and 7 patients developed cancer metastasis following surgery. With the exception of 2 patients that succumbed to disease, the remaining patients in the CSR group survived without cancer recurrence. In the TSR group, all of the patients experienced cancer recurrence within five years post-surgery. A total of 61 patients developed metastases in the three years following surgery, and 71 patients succumbed to cancer metastasis within five years. The survival rate of the CSR group was significantly increased compared with the TSR group. The results of the present study suggest that in DTC patients with defects involving up to 8 tracheal rings, it may be appropriate to perform anastomosis without suprahyoid tissue release as it is associated with a reduced incidence of perioperative morbidity.

Management of Invasive Differentiated Thyroid Cancer

BACKGROUND

Invasive disease is a poor prognostic factor for patients with differentiated thyroid cancer (DTC). Uncontrolled central neck disease is a common cause of distressing death for patients presenting in this manner. Advances in assessment and management of such cases have led to significant improvements in outcome for this patient group. This article reviews the patterns of invasion and a contemporary approach to investigation and treatment of patients with invasive DTC.

SUMMARY

Aerodigestive tract invasion is reported in around 10% of case series of DTC. Assessment should include not only clinical history and physical examination with endoscopy as indicated, but ultrasound and contrast-enhanced cross-sectional imaging. Further studies including positron emission tomography should be considered, particularly in recurrent cases that are radioactive iodine (RAI) resistant. Both the patient and the extent of disease should be carefully assessed prior to embarking on surgery. The aim of surgery is to resect all gross disease. When minimal visceral invasion is encountered early, "shave" procedures are recommended. In the setting of transmural invasion of the airway or esophagus, however, full thickness excision is required. For intermediate cases in which invasion of the viscera has penetrated the superficial layers but is not evident in the submucosa, opinion is divided. Early reports recommended an aggressive approach. More recently authors have tended to recommend less aggressive resections with postoperative adjuvant therapies. The role of external beam radiotherapy continues to evolve in DTC with support for its use in patients considered to have RAI-resistant tumors.

CONCLUSIONS

Patients with invasive DTC require a multidisciplinary approach to investigation and treatment. With detailed assessment, appropriate surgery, and adjuvant therapy when indicated, this patient group can expect durable control of central neck disease, despite the aggressive nature of their primary tumors.

Operative management of locally advanced, differentiated thyroid cancer

BACKGROUND

The majority of differentiated thyroid cancer tends to present with limited locoregional disease, leading to excellent long-term survival after operative treatment. Even patients with advanced local disease may survive for long periods with appropriate treatment. The aim of this study is to present our institutional experience of the management of locally advanced differentiated thyroid cancer and to analyze factors predictive of outcome.

METHODS

We reviewed our institutional database of 3,664 previously untreated patients with differentiated thyroid cancer operated between 1986 and 2010. A total of 153 patients had tumor extension beyond the thyroid capsule that invaded the subcutaneous soft tissues, recurrent laryngeal nerve, larynx, trachea, or esophagus. Details on extent of operation and adjuvant therapy were recorded. Disease-specific survival and locoregional recurrence-free probability were determined by the Kaplan-Meier method. Factors predictive of outcome were determined by multivariate analysis.

RESULTS

The median age of the 153 patients with tumor extension beyond the thyroid capsule was 55 years (range 11-91 years). Eighty-nine patients (58.2%) were female. Twenty-three patients (15.0%) were staged as M1 at presentation, and 122 (79.7%) had pathologically involved lymph nodes. The most common site of extrathyroidal extension was the recurrent laryngeal nerve (51.0%) followed by the trachea (46.4%) and esophagus (39.2%). Sixty-three patients (41%) required resection of the recurrent laryngeal nerve due to tumor involvement. After surgery, 20 patients (13.0%) had gross residual disease (R2), 63 (41.2%) had a positive margin of resection (R1), and 70 (45.8%) had complete resection with negative margins (R0). With a median follow-up of 63.9 months, 5-year, disease-specific survival, when stratified by R0/R1/R2 resection, was 94.4%, 87.6%, and 67.9%, respectively (P = .030). The data do not demonstrate a statistical difference in survival between R0 versus R1 (P = .222). The 5-year distant recurrence-free probability for M0 patients was 90.8%, 90.3%, and 70.7% (P = .410). The locoregional recurrence-free probability was 85.8% for R0 patients and 85.5% for R1 patients (P = .593).

CONCLUSION

With an appropriate operative strategy, patients with locally advanced thyroid cancer with an R0 or R1 resection have excellent survival outcome.

Surgical management of laryngeal invasion by papillary thyroid carcinoma: a retrospective analysis

BACKGROUND

Papillary thyroid carcinoma (PTC) has an excellent prognosis. Although rare, PTC invasion into the upper aerodigestive tract can adversely affect patient prognosis and quality of life. This study investigated the impact of tumor excision on the prognosis and postoperative status of patients with PTC invasion of the larynx.

METHODS

Data on PTC patients who underwent surgery at the author's institution between April 1981 and March 2010 were retrospectively reviewed, and 55 patients with thyroid cartilage invasion were enrolled. Curative resection was performed for all patients, and laryngeal function was preserved or reconstructed when possible.

RESULTS

Of the 55 patients, 40 and 15 patients had superficial and intraluminal invasion of the larynx, respectively. The 10-year disease-specific survival rates were 81.0% and 61.4% in patients who underwent surgery for superficial and intraluminal invasion of the larynx, respectively. Only two patients (3.6%) had an isolated locoregional recurrence in the larynx. Four patients (7.3%) underwent total laryngectomy during the initial surgery or surgery for laryngeal recurrence. Permanent stoma remained in 26 patients (47%): 14 with laryngeal invasion, and 12 with invasion of other aerodigestive structures. The number of invaded aerodigestive structures including the larynx was correlated with the presence of permanent stoma.

CONCLUSIONS

In many patients, PTC invasion of the larynx remained at the thyroid cartilage or paraglottic space. Most patients did not require total laryngectomy. Good locoregional control was achieved with surgical tumor excision in patients with laryngeal invasion. Distant metastases were the major cause of death in patients with PTC invasion of the larynx.

Surgical Management of Cricotracheal Invasion by Papillary Thyroid Carcinoma

BACKGROUND

In general, patients with papillary thyroid carcinoma (PTC) have an excellent postoperative prognosis. Those with cricoid and/or tracheal PTC invasion, however, are at a higher risk of postoperative morbidity and airway insufficiency.

METHODS

We investigated postoperative airway outcomes, locoregional recurrence, and survival rates in patients with PTC who underwent cricotracheal resection. The records of PTC patients who underwent surgery at our institution between 1981 and 2009 were reviewed retrospectively, and 110 patients with cricotracheal invasion were enrolled. Curative resection was performed in all patients, and cricotracheal function was preserved or reconstructed when possible.

RESULTS

Of the 110 patients, 57 and 53 patients had superficial and intraluminal invasion of the larynx, respectively. After the initial surgery, the 10-year disease-specific survival rates were 90.8 and 44.4 % in patients with superficial and intraluminal invasion of the cricotracheal area, respectively. Only six patients (5.5 %) had an isolated upper aerodigestive tract recurrence. Five patients were managed with an additional window resection as salvage surgery. Consequently, only one patient (0.9 %) underwent total laryngectomy. Altogether, 31 patients (28.0 %) had a permanent stoma, 9 and 15 of which were caused by cricotracheal invasion and invasion of other aerodigestive structures, respectively.

CONCLUSIONS

Window resection for intraluminal cricotracheal invasion by PTC produced good surgical outcomes that resulted in a low local recurrence rate and survival rates that resembled those associated with other surgical treatments. Treatment of multiple organ invasion of the aerodigestive tract was necessary to improve postoperative functional outcomes in these patients.

Management of invasive well-differentiated thyroid cancer: an American Head and Neck Society consensus statement. AHNS consensus statement

BACKGROUND

Invasive differentiated thyroid cancer (DTC) is relatively frequent, yet there is a paucity of specific guidelines devoted to its management. The Endocrine Committee of the American Head and Neck Society (AHNS) convened a panel to provide clinical consensus statements based on review of the literature, synthesized with the expert opinion of the group.

METHODS

An expert panel, selected from membership of the AHNS, constructed the manuscript and recommendations for management of DTC with invasion of recurrent laryngeal nerve, trachea, esophagus, larynx, and major vessels based on current best evidence. A Modified Delphi survey was then constructed by another expert panelist utilizing 9 anchor points, 1 = strongly disagree to 9 = strongly agree. Results of the survey were utilized to determine which statements achieved consensus, near-consensus, or non-consensus.

RESULTS

After endorsement by the AHNS Endocrine Committee and Quality of Care Committee, it received final approval from the AHNS Council.

Classification of aerodigestive tract invasion from thyroid cancer

BACKGROUND

Widely invasive extrathyroidal thyroid cancer invading the aerodigestive tract (ADT) including larynx, trachea, hypopharynx, and/or esophagus occurs in 1-8 % of patients with thyroid cancer and is classified as T4a (current UICC/AJCC system). The T4a stage is associated with impaired tumor-free survival and increased disease-specific mortality. Concerning prognosis and outcome, further subdivisions of the T4a stage, however, have not been made so far.

METHODS

This study is based on a systematic review of the relevant literature in the PubMed database.

RESULTS

Retrospective studies suggest a better outcome in patients with invasion of the trachea or the esophagus when compared to laryngeal invasion. Regarding surgical strategies, ADT invasion can be classified based on a three-dimensional assessment determining surgical resection options. Regardless of the invaded structure, tumor infiltration of the ADT can be subdivided into superficial, deep extraluminal, and intraluminal invasion. In contrast to superficial ADT invasion, allowing tangential incomplete wall resection (shaving/extramucosal esophagus resection), deeper wall and intraluminal invasions require complete wall resection (either window or sleeve). Based on the Dralle classification (types 1-6), particularly airway invasion, can be further classified according to the vertical and horizontal extents of tumor invasion.

CONCLUSIONS

The Dralle classification can be considered as a reliable subdivision system evaluated regarding surgical options as well as oncological outcome. However, further studies determining the prognostic impact of this technically oriented classification system are required.

Thyroid cancer: surgery for the primary tumor

Surgery is the mainstay of therapy for most patients who present with thyroid cancer. The surgeon must select an appropriate procedure based upon pre operative factors such as tumor histology, extent of primary disease, the presence of regional or distant metastases, associated disease in the contralateral thyroid lobe and the potential for post operative adjuvant therapy. Preservation of the vital structures in the central neck, including the recurrent and superior laryngeal nerves and the parathyroid glands is critical as is the maintenance of absolute hemostasis. In this review article we describe the management of Well Differentiated Thyroid Cancer (WDTC) presenting as a solitary nodule, WDTC in a background of multinodular disease and the management of WDTC presenting as advanced local disease. We go onto discuss the impact that regional and distant metastases have on the choice of surgical approach. The focus of this article is WDTC, however the principles of management of the primary in medullary and anaplastic carcinoma are also discussed.

[Extrathyroidal thyroid cancer : results of tracheal shaving and tracheal resection]

Extrathyroidal thyroid cancer invading the laryngotracheal system (UICC stage pT4a) represents a progressive process of infiltration of the tracheal wall layers from the outer to the inner parts of the trachea. These tumors usually present with high proliferation activity correlating with a reduced long-term prognosis. In contrast to intraluminal manifestation requiring complete wall resection, in cases of non-transmural invasion, complete tumor removal can be sometimes achieved by extraluminal tangential resection (shaving). Tangential resections, however, are associated with a higher frequency of microscopically invaded resection margins (R1 resection rate >40%). The available comparative studies (all retrospective, maximum EBM level 3) analyzing oncological outcome show inconsistent results. In more recently published studies, however, complete wall resection in well-differentiated thyroid cancer with tracheal invasion only was found to be associated with longer recurrence-free and tumor-specific survival when compared to shaving. Deep larynx invasion is associated with reduced long-term prognosis when compared to invasion of the trachea. Salvage resections should therefore be performed in selected cases only.

Surgical treatment of patients with stenosis of the central airway due to tracheal tumours

This study retrospectively evaluated bronchoscopic and surgical treatments for patients with central airway stenosis due to tracheal tumours. Seven patients treated by resection and reconstruction of the trachea for tracheal tumours between 1994 and 2008 were retrospectively reviewed. The most common histological finding was thyroid carcinoma (n = 3), followed by adenoid cystic carcinoma (n = 2), a metastatic thyroid tumour (n = 1), and a benign granular cell tumour (n = 1). Three of the patients required preoperative laser treatment (Nd:YAG) for recanalization. Five patients underwent end-to-end anastomosis for reconstruction. There was no postoperative mortality or morbidity such as anastomotic insufficiency of the reconstructed trachea. Three patients with a microscopic residual tumour required postoperative external radiotherapy. Surgical resection of malignant tracheal tumours is recommended not only for curative purposes, but also for reduction of the risk of smothering.

The management of thyroid carcinoma invading the larynx or trachea

OBJECTIVES/HYPOTHESIS

To describe the controversies in the management of thyroid carcinoma invading the airway.

STUDY DESIGN

Contemporary review of literature; level of evidence: 5.

RESULTS

Invasion of the larynx or trachea by thyroid carcinoma is uncommon and often identified at the time of operation, when the surgeon must decide the extent of resection. Invasion of the airway is associated with loss of tumor differentiation and a reduction in long-term survival compared to tumors limited to the thyroid gland. Whether or not the invaded airway should be resected remains controversial. Tangential shave excision of tumor is commonly performed, despite a marked risk of local recurrence. Circumferential sleeve resection of the larynx and trachea is safe and lowers the risk of local recurrence. In recurrent disease, laryngotracheal resection provides effective palliation of airway obstruction and hemoptysis.

CONCLUSIONS

Long-term (>10-20 years) prospective studies are required to compare the outcome after shave excision with segmental airway resection for thyroid carcinoma. Based on the current literature and on our experience, we advocate circumferential tracheal resection in the setting of airway involvement.

Tracheal resection with end-to-end anastomosis preserving paries membranaceus trachea for patients with papillary thyroid carcinoma

CONCLUSION

Sleeve resection of the trachea while preserving the paries membranaceus trachea appears useful for patients in whom papillary thyroid carcinoma has invaded as far as the tracheal mucosa.

OBJECTIVES

While tracheal sleeve resection with end-to-end anastomosis is advantageous, risks of suture failure or other serious complications exist. Since feeding arteries enter the trachea from the posterior and lateral walls, we conduct tracheal anastomosis preserving the paries membranaceus trachea.

PATIENTS AND METHODS

This study retrospectively examined therapeutic outcomes and postoperative complications for sleeve resection followed by end-to-end anastomosis in 12 patients between 1994 and 2005.

RESULTS

Tracheal suture failure occurred in one patient and sutures were redone. One patient developed esophageal fistula, but recovered with conservative treatment. One patient required re-intubation. In three patients, recurrent laryngeal nerves were paralyzed bilaterally. No patients displayed recurrence in the tracheal resection margin or preserved paries membranaceus trachea. The 10-year survival rate was 72.9%.

The fate of homograft tracheal transplants in sheep

OBJECTIVE

An established method of tracheal substitution is not yet available, but homograft tracheal transplantation might provide a realistic tracheal replacement. With the objective of sequentially examining the healing of tracheal homografts, we have established a suitable large-animal model.

METHODS

Five sheep received orthotopic tracheal transplantation of a 4-cm cervical tracheal homograft. The trachea was supported for 6 weeks with a self-expanding polyester stent. The plan was to euthanize the animals after 2, 4, 8, 12 and 16 weeks, or whenever complications occurred.

RESULTS

The implantation itself was performed without complications. After 2 weeks the homograft was firmly encapsulated by connective tissue, without signs of necrosis or abscess. The original mucous membrane no longer existed; the cartilage rings were exposed. In all animals that were euthanized at the later dates, the homografts were completely absorbed and replaced by inflammatory scar tissue. This, in turn, was covered with a shiny cellular surface layer.

CONCLUSIONS

The results from this animal experiment reveal-contrary to data published to date-that tracheal homografts are not incorporated but absorbed. They are replaced by scar/granulation tissue that cannot secure the stability of the trachea. Therefore, further experiments with respect to the biocompatability of homografts appear to be necessary.