Long-term efficacy of lymph node reoperation for persistent papillary thyroid cancer

Ten-Year Outcomes of Radiofrequency Ablation for Locally Recurrent Papillary Thyroid Cancer

OBJECTIVE

This study investigates the long-term efficacy and safety of ultrasound (US)-guided radiofrequency ablation (RFA) for treating locally recurrent papillary thyroid cancer (PTC).

MATERIALS AND METHODS

We retrospectively analyzed 39 consecutive patients with 61 locally recurrent PTCs (14 males, 25 females; mean ± standard deviation age, 52.8 ± 16.7 years; range 21-92 years) who underwent US-guided RFA with curative intent between September 2008 and April 2012. A subgroup of 24 patients with 37 recurrent PTCs who had a follow-up of at least 10 years were analyzed separately. All patients were followed for changes in lesion size on US and thyroglobulin (Tg) levels at 1, 3, 6, and 12 months after RFA, with follow-up every 6-12 months thereafter. Any complications were documented during the follow-up period. Recurrence-free survival (RFS) rates were assessed using Kaplan-Meier estimates. Long-term outcomes were evaluated in patients with follow-up of at least 10 years.

RESULTS

The follow-up period ranged from 7 to 180 months (median 133 months). The RFS rates for the 39 patients at 3, 5, and 10 years were 86.8%, 75.5%, and 60.6%, respectively. Among the 24 patients with 37 recurrent PTCs followed for more than 10 years, the volume reduction rate was 99.9% (range 96%-100%), and the complete tumor disappearance rate was 91.9%. The mean serum Tg level also decreased significantly, from 2.66 ± 86.5 mIU/L before ablation to 0.43 ± 0.73 mIU/L (P < 0.001) at the final follow-up. In 14 (58.3%) of the 24 patients, Tg levels were undetectable (below 0.08 mIU/L) at the last follow-up. No life-threatening or delayed complications were observed during the 10-year follow-up period.

CONCLUSION

The high RFS throughout the follow-up period, with efficacy and safety lasting beyond 10 years, supports US-guided RFA as a valuable option for local control of recurrent PTCs.

Surgical and Biochemical Outcomes in Nerve Monitored Reoperation Surgery for Recurrent Papillary Thyroid Carcinoma

OBJECTIVE

To study the surgical and biochemical outcomes in nerve-monitored reoperation or revision surgery for recurrent thyroid cancers.

STUDY DESIGN

A single-center retrospective study.

SETTING

Tertiary center.

METHODS

We identified patients with recurrent papillary thyroid carcinoma (PTC) who underwent reoperation/revision surgery. Study outcomes were surgical complications frequency, recurrence, distant metastasis, and biological complete response (BCR) by comparing preoperative and postoperative thyroglobulin (Tg) levels.

RESULTS

Out of 227 patients, 33.9% presented for ≥2 reoperation surgeries. Nineteen (8.4%) had permanent preoperative hypoparathyroidism while 22 patients (9.7%) had preoperative vocal cord paralysis (VCP). Following reoperation surgery, there were 12 cases (5.3%) of permanent hypocalcemia and no cases of unexpected postoperative VCP. BCR was achieved in 31 patients (35.2%) with complete Tg data. Mean preoperative Tg was 47.7 ng/mL and was 19.7 ng/mL postoperatively (p = .003). The cervical nodal recurrence rate after final surgery was 7.0% (n = 16).

CONCLUSION

Reoperation surgery for recurrent PTC may help achieve biochemical remission regardless of age or the number of prior surgeries.

Ultrasound-Guided Ethanol Percutaneous Ablation Versus Rescue Surgery in Patients With Locoregional Recurrence of Papillary Thyroid Cancer

OBJECTIVES

Neck recurrence of papillary thyroid cancer (PTC) is frequently detected after initial surgery. The management of these lesions may include rescue surgery (RS) or minimally invasive techniques in selected patients, but comparative studies evaluating the effectiveness and safety of these techniques are lacking. In this paper, we compared ultrasound-guided ethanol ablation (EA) in selected patients to RS in a matched cohort.

METHODS

We retrospectively compared 41 patients and 41 matched PTC patients without known distant metastases, who underwent ultrasound-guided EA or RS (matched reference group), who had 63 and 75 thyroid bed and/or lymph node confirmed PTC recurrences during a median follow-up of 72.8 and 89.6 months, respectively. The primary outcome was time until structural recurrence, compared using Kaplan-Meier survival curves. The secondary outcomes included time until biochemical recurrence, plasma thyroglobulin (Tg) levels, American Thyroid Association (ATA) response-to-therapy categories by the last available observation, and treatment-derived complications in each group.

RESULTS

No significant differences were found between the EA and RS groups for time until structural recurrence (log-rank test, P=0.94). The time until biochemical recurrence was also similar (P=0.51); and the plasma Tg concentration reduction and proportions of patients in the ATA reclassification categories were also similar. A significantly higher proportion of patients in the RS group presented treatment-derived complications (29.27% vs. 9.75%, P<0.05).

CONCLUSION

In this retrospective analysis, the treatment of PTC neck recurrence with EA in selected patients was comparable to RS in a matched reference group for the long-term risk of structural or biochemical relapse, but with a lower risk of treatment-derived complications. These.

RESULTS

support the effectiveness and safety of this minimally invasive technique in the management of selected patients with recurrent PTC.

Diagnosis of Metastatic Lymph Nodes in Patients With Papillary Thyroid Cancer: A Comparative Multi-Center Study of Semantic Features and Deep Learning-Based Models

OBJECTIVES

Deep learning algorithms have shown potential in streamlining difficult clinical decisions. In the present study, we report the diagnostic profile of a deep learning model in differentiating malignant and benign lymph nodes in patients with papillary thyroid cancer.

METHODS

An in-house deep learning-based model called "ClymphNet" was developed and tested using two datasets containing ultrasound images of 195 malignant and 178 benign lymph nodes. An expert radiologist also viewed these ultrasound images and extracted qualitative imaging features used in routine clinical practice. These signs were used to train three different machine learning algorithms. Then the deep learning model was compared with the machine learning models on internal and external validation datasets containing 22 and 82 malignant and 20 and 76 benign lymph nodes, respectively.

RESULTS

Among the three machine learning algorithms, the support vector machine model (SVM) outperformed the best, reaching a sensitivity of 91.35%, specificity of 88.54%, accuracy of 90.00%, and an area under the curve (AUC) of 0.925 in all cohorts. The ClymphNet performed better than the SVM protocol in internal and external validation, achieving a sensitivity of 93.27%, specificity of 92.71%, and an accuracy of 93.00%, and an AUC of 0.948 in all cohorts.

CONCLUSION

A deep learning model trained with ultrasound images outperformed three conventional machine learning algorithms fed with qualitative imaging features interpreted by radiologists. Our study provides evidence regarding the utility of ClymphNet in the early and accurate differentiation of benign and malignant lymphadenopathy.

Guidelines from the Brazilian society of surgical oncology regarding indications and technical aspects of neck dissection in papillary, follicular, and medullary thyroid cancers

Objective

The purpose of these guidelines is to provide specific recommendations for the surgical treatment of neck metastases in patients with papillary, follicular, and medullary thyroid carcinomas.

Materials and methods

Recommendations were developed based on research of scientific articles (preferentially meta-analyses) and guidelines issued by international medical specialty societies. The American College of Physicians' Guideline Grading System was used to determine the levels of evidence and grades of recommendations. The following questions were answered: A) Is elective neck dissection indicated in the treatment of papillary, follicular, and medullary thyroid carcinoma? B) When should central, lateral, and modified radical neck dissection be performed? C) Could molecular tests guide the extent of the neck dissection?

Results and conclusion

Recommendation 1: Elective central neck dissection is not indicated in patients with cN0 well-differentiated thyroid carcinoma or in those with noninvasive T1 and T2 tumors but may be considered in T3-T4 tumors or in the presence of metastases in the lateral neck compartments. Recommendation 2: Elective central neck dissection is recommended in medullary thyroid carcinoma. Recommendation 3: Selective neck dissection of levels II-V should be indicated to treat neck metastases in papillary thyroid cancer, an approach that decreases the risk of recurrence and mortality. Recommendation 4: Compartmental neck dissection is indicated in the treatment of lymph node recurrence after elective or therapeutic neck dissection; "berry node picking" is not recommended. Recommendation 5: There are currently no recommendations regarding the use of molecular tests in guiding the extent of neck dissection in thyroid cancer.

Recurrent Differentiated Thyroid Cancer: The Current Treatment Options

Differentiated thyroid carcinomas (DTC) have an excellent prognosis, but this is sometimes overshadowed by tumor recurrences following initial treatment (approximately 15% of cases during follow-up), due to unrecognized disease extent at initial diagnosis or a more aggressive tumor biology, which are the usual risk factors. The possible sites of recurrence are local, regional, or distant. Local and regional recurrences can usually be successfully managed with surgery and radioiodine therapy, as are some isolated distant recurrences, such as bone metastases. If these treatments are not possible, other therapeutic options such as external beam radiation therapy or systemic treatments should be considered. Major advances in systemic treatments have led to improved progression-free survival in patients previously considered for palliative treatments; among these treatments, the most promising results have been achieved with tyrosine kinase inhibitors (TKI). This review attempts to give a comprehensive overview of the current treatment options suited for recurrences and the new treatments that are available in cases where salvage surgery is not possible or in cases resistant to radioiodine.

Diagnosis of cervical lymph node metastasis with thyroid carcinoma by deep learning application to CT images

Introduction

The incidence of thyroid diseases has increased in recent years, and cervical lymph node metastasis (LNM) is considered an important risk factor for locoregional recurrence. This study aims to develop a deep learning-based computer-aided diagnosis (CAD) method to diagnose cervical LNM with thyroid carcinoma on computed tomography (CT) images.

Methods

A new deep learning framework guided by the analysis of CT data for automated detection and classification of LNs on CT images is proposed. The presented CAD system consists of two stages. First, an improved region-based detection network is designed to learn pyramidal features for detecting small nodes at different feature scales. The region proposals are constrained by the prior knowledge of the size and shape distributions of real nodes. Then, a residual network with an attention module is proposed to perform the classification of LNs. The attention module helps to classify LNs in the fine-grained domain, improving the whole classification network performance.

Results

A total of 574 axial CT images (including 676 lymph nodes: 103 benign and 573 malignant lymph nodes) were retrieved from 196 patients who underwent CT for surgical planning. For detection, the data set was randomly subdivided into a training set (70%) and a testing set (30%), where each CT image was expanded to 20 images by rotation, mirror image, changing brightness, and Gaussian noise. The extended data set included 11,480 CT images. The proposed detection method outperformed three other detection architectures (average precision of 80.3%). For classification, ROI of lymph node metastasis labeled by radiologists were used to train the classification network. The 676 lymph nodes were randomly divided into 70% of the training set (73 benign and 401 malignant lymph nodes) and 30% of the test set (30 benign and 172 malignant lymph nodes). The classification method showed superior performance over other state-of-the-art methods with an accuracy of 96%, true positive and negative rates of 98.8 and 80%, respectively. It outperformed radiologists with an area under the curve of 0.894.

Discussion

The extensive experiments verify the high efficiency of the proposed method. It is considered instrumental in a clinical setting to diagnose cervical LNM with thyroid carcinoma using preoperative CT images. The future research can consider adding radiologists' experience and domain knowledge into the deep-learning based CAD method to make it more clinically significant.

Conclusion

The extensive experiments verify the high efficiency of the proposed method. It is considered instrumental in a clinical setting to diagnose cervical LNM with thyroid carcinoma using preoperative CT images.

Clinical Significance of the Lymph Node Ratio of the Second Operation to Predict Re-Recurrence in Thyroid Carcinoma

The purpose of this study was to establish the risk factors for re-recurrences and disease-specific mortality (DSM) in recurrent thyroid cancer. Patients with recurrent thyroid cancer who underwent initial thyroid surgery from January 2000 to December 2019 at Seoul St. Mary's Hospital (Seoul, Korea) were assessed. Clinicopathological characteristics and long-term oncologic outcomes were compared between patients with one recurrence (n = 202) and patients with re-recurrences (n = 44). Logistic regression and cox-regression analyses were conducted to determine the risk factors for re-recurrences and DSM, respectively. Receiver-operating characteristic curve analysis was performed to determine the cutoff value for lymph node ratio (LNR) as a predictor of re-recurrences. DSM was significantly higher in the re-recurrence group compared with the single-recurrence group (6.8% vs. 0.5%, p = 0.019). Surgical treatment at the first recurrence significantly lowered the risk of re-recurrences. Age (≥55), male sex, and LNR (≥0.15) were independent significant risk factors for re-recurrences in patients who underwent surgery at the first recurrence. Surgical resection is the optimal treatment for initial thyroid cancer recurrence. LNR at re-operation is more effective in predicting re-recurrence than the absolute number of metastatic LNs.

Active surveillance in differentiated thyroid cancer: a strategy applicable to all treatment categories response

Currently, the differentiated thyroid cancer (DTC) management is shifted toward a tailored approach based on the estimated risks of recurrence and disease-specific mortality. While the current recommendations on the management of metastatic and progressive DTC are clear and unambiguous, the management of slowly progressive or indeterminate disease varies according to different centers and different physicians. In this context, active surveillance (AS) becomes the main tool for clinicians, allowing them to plan a personalized therapeutic strategy, based on the risk of an unfavorable prognosis, and to avoid unnecessary treatment. This review analyzes the main possible scenarios in treated DTC patients who could take advantage of AS.

The outcomes and prognostic factors of patients who underwent reoperation for persistent/recurrent papillary thyroid carcinoma

BACKGROUND

While the most suitable approach for treating persistent/recurrent papillary thyroid carcinoma (PTC) remains controversial, reoperation may be considered an effective method. The efficacy of reoperation in patients with locoregional persistent/recurrent PTC, especially those with unsatisfactory radioactive iodine (RAI) ablation results, is still uncertain. This study aimed to clarify the clinical management strategies for locoregional persistent/recurrent PTC and to explore factors that may affect long-term patient outcomes after reoperation.

METHODS

In total, 124 patients who initially underwent thyroidectomy and variable extents of RAI therapy and finally received reoperation for locoregionally persistent/recurrent PTC were included. The parameters associated with recurrence-free survival (RFS) were analysed using a Cox proportional hazards model.

RESULTS

Overall, 124 patients presented with structural disease after initial therapy and underwent secondary surgical resection, of whom 32 patients developed further structural disease during follow-up after reoperation. At the time of reoperation, metastatic lymph nodes with extranodal extension (P = 0.023) and high unstimulated thyroglobulin (unstim-Tg) levels after reoperation (post-reop) (P = 0.001) were independent prognostic factors for RFS. Neither RAI avidity nor the frequency and dose of RAI therapies before reoperation affected RFS.

CONCLUSIONS

Reoperation is an ideal clinical treatment strategy for structural locoregional persistent/recurrent PTC, and repeated empirical RAI therapies performed prior to reoperation may not contribute to the long-term outcomes of persistent/recurrent PTC patients. Metastatic lymph nodes with extranodal extension and post-reop unstim-Tg > 10.1 ng/mL may predict a poor prognosis.

A Combination of Contrast-Enhanced Ultrasound and Thyroglobulin Level in Fine-Needle Aspirates Improves Diagnostic Accuracy for Metastatic Lymph Nodes of Papillary Thyroid Carcinoma

OBJECTIVE

To evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) combined with thyroglobulin (Tg) levels in fine-needle aspirates (FNA) washout fluid (FNA-Tg) in diagnosing cervical lymph node (LN) metastasis in papillary thyroid cancer (PTC) patients.

METHODS

Data from 190 LNs in 167 patients suspected of metastasis from the US between November 2018 and September 2020 were included. All subjects underwent FNA, CEUS, and FNA-Tg examinations. The final outcomes were confirmed by histopathological or cytological examination or follow-up imaging. Data were analyzed using the Wilcoxon rank-sum or chi-squared test. The diagnostic efficacy of FNA, CEUS, and FNA-Tg in diagnosing LNs was compared.

RESULTS

A cutoff value of 6.15 ng/ml (AUC 0.925, 95% confidence interval (CI) 0.885-0.966) successfully identified metastatic LNs. FNA missed 58 LN metastases, of these, 94.8% (55/58) were correctly diagnosed using the combination of CEUS and FNA-Tg. FNA-Tg showed higher sensitivity (90.2%), NPV (86.1%) and accuracy (88.9%) than either FNA (48.2, 57.4 and 69.5%, respectively) or CEUS (82.1, 67.7 and 70.5%, respectively) alone. The combination of CEUS, FNA and FNA-Tg resulted in maximal sensitivity (100%) and NPV (100%) but reduced specificity (51.3%) and overall diagnostic accuracy (80.0%). After adding FNA-Tg to discordant samples between CEUS and FNA, 81.9% of LNs (77/94) were correctly diagnosed.

CONCLUSIONS

The combination of FNA, FNA-Tg and CEUS was found to be a promising imaging tool in detecting metastatic LNs in PTC patients.

Effect of prophylactic central neck dissection following total thyroidectomy on surgical site wound infection, hematoma, and haemorrhage in subjects with clinically node-negative papillary thyroid carcinoma: A meta-analysis

We performed a meta-analysis to evaluate the effect of prophylactic central neck dissection following total thyroidectomy on surgical site wound infection, hematoma, and haemorrhage in subjects with clinically node-negative papillary thyroid carcinoma. A systematic literature search up to April 2022 was performed and 3517 subjects with clinically node-negative papillary thyroid carcinoma at the baseline of the studies; 1503 of them were treated with prophylactic central neck dissection following total thyroidectomy, and 2014 were using total thyroidectomy. Odds ratio (OR) with 95% confidence intervals (CIs) were calculated to assess the effect of prophylactic central neck dissection following total thyroidectomy on surgical site wound infection, hematoma, and haemorrhage in subjects with clinically node-negative papillary thyroid carcinoma using the dichotomous method with a random or fixed-effect model. The prophylactic central neck dissection following total thyroidectomy subjects had a significantly lower surgical site wound infection (OR, 0.40; 95% CI, 0.20-0.78, P = .007) in subjects with clinically node-negative papillary thyroid carcinoma compared with total thyroidectomy. However, prophylactic central neck dissection following total thyroidectomy did not show any significant difference in hematoma (OR, 0.08; 95% CI, 0.43-2.71, P = .87), and haemorrhage (OR, 0.72; 95% CI, 0.26-1.97, P = .52) compared with total thyroidectomy in subjects with clinically node-negative papillary thyroid carcinoma. The prophylactic central neck dissection following total thyroidectomy subjects had a significantly higher surgical site wound infection, and no significant difference in hematoma, and haemorrhage compared with total thyroidectomy in subjects with clinically node-negative papillary thyroid carcinoma. The analysis of outcomes should be with caution because of the low number of studies in certain comparisons.

Revision Thyroid Surgery

The incidence of recurrence in well-differentiated thyroid malignancies range from 10 to 30%. It is estimated that about 31-46% of patients with differentiated thyroid cancer will have the persistent disease and 1.2-6.8% will have structural recurrences during post-operative monitoring, depending on the initial therapy and prognostic variables. It is challenging to decide on treatment versus active monitoring following repeated or persistent tumour detection. The biological factors of the tumour and the patient guide us in the overall decision-making. Revision thyroid surgery is technically challenging. The morbidity encountered during the revision surgery is related to the anatomy of the region undergoing dissection, the degree of fibrosis and scarring from prior surgery and the operating surgeon's experience. Successful comprehensive management of revision thyroid surgery needs a multi-disciplinary approach. This review article highlights the definition, indications for revision surgery, identification of recurrent disease, management of parathyroid and recurrent laryngeal nerves with neuromonitoring.

European Thyroid Association and Cardiovascular and Interventional Radiological Society of Europe 2021 Clinical Practice Guideline for the Use of Minimally Invasive Treatments in Malignant Thyroid Lesions

The growing detection of papillary thyroid microcarcinomas (PTMCs) is paralleled by an increase in surgical procedures. Due to the frequent indolent nature, cost, and risk of surgery, active surveillance (AS) and ultrasound-guided minimally invasive treatments (MITs) are in suitable cases of incidental PTMC proposed as alternatives to thyroidectomy. Surgery and radioiodine are the established treatments for relapsing cervical differentiated thyroid carcinoma (DTC) metastases. But radioiodine refractoriness, risk of surgical complications, adverse influence on quality of life, or declining repeat surgery have led to AS and MIT being considered as alternatives for slow-growing DTC nodal metastases. Also, for distant radioiodine-refractory metastases not amenable to surgery, MIT is proposed as part of a multimodality therapeutic approach. The European Thyroid Association and the Cardiovascular and Interventional Radiological Society of Europe commissioned these guidelines for the appropriate use of MIT. Based on a systematic PubMed search, an evidence-based approach was applied, and both knowledge and practical experience of the panelists were incorporated to develop the manuscript and the specific recommendations. We recommend that when weighing between surgery, radioiodine, AS, or MIT for DTC, a multidisciplinary team including members with expertise in interventional radiology assess the demographic, clinical, histological, and imaging characteristics for appropriate selection of patients eligible for MIT. Consider TA in low-risk PTMC patients who are at surgical risk, have short life expectancy, relevant comorbidities, or are unwilling to undergo surgery or AS. As laser ablation, radiofrequency ablation, and microwave ablation are similarly safe and effective thermal ablation (TA) techniques, the choice should be based on the specific competences and resources of the centers. Use of ethanol ablation and high-intensity focused ultrasound is not recommended for PTMC treatment. Consider MIT as an alternative to surgical neck dissection in patients with radioiodine refractory cervical recurrences who are at surgical risk or decline further surgery. Factors that favor MIT are previous neck dissection, presence of surgical complications, small size metastases, and <4 involved latero-cervical lymph nodes. Consider TA among treatment options in patients with unresectable oligometastatic or oligoprogressive distant metastases to achieve local tumor control or pain palliation. Consider TA, in combination with bone consolidation and external beam radiation therapy, as a treatment option for painful bone metastases not amenable to other established treatments.

Management of the Neck in Well-Differentiated Thyroid Cancer

PURPOSE OF REVIEW

In this narrative review, we discuss the indications for elective and therapeutic neck dissections and the postoperative surveillance and treatment options for recurrent nodal disease in patients with well-differentiated thyroid cancer.

RECENT FINDINGS

Increased availability of advanced imaging modalities has led to an increased detection rate of previously occult nodal disease in thyroid cancer. Nodal metastases are more common in young patients, large primary tumors, specific genotypes, and certain histological types. While clinically evident nodal disease in the lateral neck compartments has a significant oncological impact, particularly in the older age group, microscopic metastases to the central or the lateral neck in well-differentiated thyroid cancer do not significantly affect outcome. As patients with clinically evident nodal disease are associated with worse outcomes, they should be treated surgically in order to reduce rates of regional recurrence and improve survival. The benefit of elective neck dissection remains unverified as the impact of microscopic disease on outcomes is not significant.

Evaluating the risk of re-recurrence in patients with persistent/recurrent thyroid carcinoma after initial reoperation

BACKGROUND

Although the 2015 American Thyroid Association guidelines proposed initial and response-to-therapy risk stratifications were adequately validated in untreated papillary thyroid cancer patients, it is still unknown how they work in persistent/recurrent papillary thyroid cancer patients. This study aimed to evaluate and revise the stratifications in these patients.

METHODS

This retrospective study included patients who received the first reoperation with complete thyroid resection but without radioactive iodine ablation. Stratifications were performed considering the persistent/recurrent tumor characteristics and thyroglobulin levels 1 to 6 months after reoperation and then revised with new prognostic factors and adjusted thyroglobulin cutoff values, respectively. Prognostic performance was evaluated with Kaplan-Meier curves, proportion of variation explained, and Harrell's concordance index.

RESULTS

Among a total of 232 patients, 5-year re-recurrence free survival rates were 92.4%, 86.2%, and 74.5% in low-, intermediate-, and high-risk patients, respectively (all P > .05) and 97.0%, 96.3%, and 81.6% in excellent response, intermediate response, and biochemical incomplete response groups, respectively (excellent response versus intermediate response, P > .05; intermediate response versus biochemical incomplete response, P < .05). After incorporating age at reoperation, recurrent primary size, and recurrent lymph node number, the high-risk group had significantly compromised re-recurrence free survival versus the intermediate-risk group (76.2% vs 91.6%). After adjusting thyroglobulin values, 5-year re-recurrence free survival rates were 96.4%, 85.9%, and 75.8% in excellent response (<1 ng/mL), intermediate response (1-10 ng/mL), and biochemical incomplete response (≥10 ng/mL) groups, respectively (all P < .05), with a higher proportion of variation explained (12.8% vs 10.1%) and concordance index (0.669 vs 0.615) compared with the American Thyroid Association version.

CONCLUSION

The revised American Thyroid Association initial and response-to-therapy risk stratifications have acceptable predictive value for persistent/recurrent papillary thyroid cancer patients.

Ultrasonographic Indeterminate Lymph Nodes in Preoperative Thyroid Cancer Patients: Malignancy Risk and Ultrasonographic Findings Predictive of Malignancy

Objective

Proper management of lymph nodes (LNs) with ultrasonographic (US) indeterminate features in thyroid cancer patients remains elusive. We aimed to evaluate the malignancy risk and US findings predictive of malignancy for US indeterminate LNs in preoperative thyroid cancer patients through node-by-node correlation.

Materials and Methods

A total of 348 LNs in 284 thyroid cancer patients, who underwent fine-needle aspiration or core-needle biopsy between December 2006 and June 2015, were included. We determined the malignancy risks for US probably benign, indeterminate, and suspicious categories. For US indeterminate LNs, which had neither echogenic hilum nor hilar vascularity in the absence of any suspicious finding, US findings were compared between benign and metastatic LNs using Mann-Whitney U test and Fisher's exact test.

Results

US imaging diagnoses were probably benign in 20.7% (n = 72) cases, indeterminate in 23.6% (n = 82), and suspicious in 55.7% (n = 194). Malignancy risk of US indeterminate LNs (19.5% [16/82]) differed from those of the US probably benign (2.8% [2/72]) (p = 0.002) and US suspicious LNs (78.4% [152/194]) (p < 0.001). Among US indeterminate LNs, there were no significant differences in short, long, and long-to-short diameter (L/S) ratios between benign and metastatic LNs (3.9 vs. 3.8 mm, p = 0.619; 7.3 vs. 7.3 mm, p = 0.590; 1.9 vs. 1.9, p = 0.652).

Conclusion

US indeterminate LNs were frequently encountered during preoperative evaluation and had intermediate malignancy risk. Given the lack of discriminative power of size criteria and L/S ratio, clinical factors such as surgical strategy and node size should be considered for proper triage of US indeterminate LNs in thyroid cancer.

The Value of Microvascular Imaging for Triaging Indeterminate Cervical Lymph Nodes in Patients with Papillary Thyroid Carcinoma

Simple Summary

Papillary thyroid carcinomas (PTC) are indolent tumors associated with excellent long-term survival, albeit frequently accompanied by cervical lymph node (LN) metastasis. The imaging criteria using conventional ultrasound (US) techniques showed high diagnostic performance for the suspicious and probably benign LN categories, but showed low diagnostic performance for the indeterminate category. In this retrospective study, we aimed to assess the added value of Superb Microvascular Imaging (SMI) for detecting metastatic PTC in the indeterminate LN category. We confirmed that SMI could effectively stratify indeterminate LNs by visualizing additional vascular signals. The reclassified categories of SMI provided a high diagnostic performance to distinguish metastasis from benign LNs. Therefore, adding SMI to conventional US scans can be useful when evaluating indeterminate LNs in patients with PTC.

Abstract

Assessment of lymph node (LN) status in patients with papillary thyroid carcinoma (PTC) is often troublesome because of cervical LNs with indeterminate US (ultrasound) features. We aimed to explore whether Superb Microvascular Imaging (SMI) could be helpful for distinguishing metastasis from indeterminate LNs when combined with power Doppler US (PDUS). From 353 consecutive patients with PTC, LNs characterized as indeterminate by PDUS were evaluated by SMI to distinguish them from metastasis. Indeterminate LNs were reclassified according to the SMI, the malignancy risk of each category was assessed, and the diagnostic performance of suspicious findings on SMI was calculated. The incidence of US-indeterminate LNs was 26.9%. Eighty PDUS-indeterminate LNs (39 proven as benign, 41 proven as malignant) were reclassified into probably benign (n = 26), indeterminate (n = 20), and suspicious (n = 34) categories according to SMI, with malignancy risks of 19.2%, 20.0%, and 94.1%, respectively. After combining SMI with PDUS, 80.8% (21/26) of probably benign LNs and 94.1% (32/34) of suspicious LNs could be correctly diagnosed as benign and metastatic, respectively. The diagnostic sensitivity, specificity, and accuracy of categorizing LNs as suspicious based on SMI were 78.1%, 94.9%, and 86.3%, respectively. In conclusion, the combination of SMI with PDUS was helpful for the accurate stratification of indeterminate LNs based on US in patients with PTC.

Efficacy of radiofrequency ablation for recurrent thyroid cancer invading the airways

OBJECTIVES

To evaluate the efficacy of radiofrequency ablation (RFA) in patients with recurrent thyroid cancer invading the airways.

METHODS

We reviewed patients who had undergone RFA for recurrent thyroid cancer in the central compartment after total thyroidectomy between January 2008 and December 2018. All tumors were classified according to their association with the laryngeal structure and trachea. The volume reduction rate (VRR) and complete disappearance rate were calculated, and their differences were determined relative to the association between the tumor and trachea. Complication rates associated with RFA were evaluated.

RESULTS

The study population included 119 patients with 172 recurrent tumors. Mean VRR was 81.2% ± 55.7%, with 124 tumors (72.1%) completely disappearing after a mean follow-up of 47.9 ± 35.4 months. The complete disappearance rate of recurrent tumors not in contact with the trachea was highest, followed by tumors forming acute angles, right angles, and obtuse angles with the trachea, and tumors with intraluminal tracheal invasion (p value < 0.001). The overall complication rate was 21.4%.

CONCLUSIONS

RFA is effective and safe for the local control of recurrent tumors in the central neck compartment after total thyroidectomy, even for tumors invading the airways, and may be considered an alternative to surgical resection. The inverse relationship between RFA efficacy and airway invasion suggests that early RFA may benefit patients with recurrent tumors in the central neck compartment.

KEY POINTS

• RFA achieved a mean VRR of 81.2% ± 55.7% and complete disappearance of 124 tumors (72.1%) after a mean follow-up of 47.9 ± 35.4 months. • The complete disappearance rate of recurrent tumors not in contact with the trachea was the highest, followed by tumors forming acute angles, right angles, and obtuse angles with the trachea, and tumors with intraluminal tracheal invasion. • Stent-assisted RFA may be a good alternative for palliative treatment of recurrent tumors with intraluminal tracheal invasion.

Reoperations for structurally persistent or recurrent disease after thyroidectomy: analysis via preoperative CT

The incidence rates of structural persistent disease (PD) and recurrent disease (RD) after thyroidectomy, and their clinicoradiological (CT) characteristics, remain poorly understood. Therefore, we characterized differentiated thyroid cancer (DTC) patients who underwent re-operations, with a focus on preoperative CT scans. We examined neck CT scans obtained prior to initial surgery and reoperation, and classified the disease into four categories according to the persistence/recurrence and neck dissection/non-dissection status. In total, 121 of 9,173 DTC patients underwent reoperations to treat PD or RD; the mean time to reoperation was 25.5 and 54.1 months, respectively. Of all reoperations, 19% (23/121) were performed to treat RD; 81% (98/121) were performed to treat PD. Compared to RD, PD was commonly detected in the non-dissected neck. Tumor multiplicity and the number of pathologically positive lymph nodes were greater in the non-dissected than dissected neck. A review of the CT data revealed more false-negative findings on the 60-s- versus 30-40-s-delay scans of PD patients with non-dissected necks. In conclusion, most of the reoperations performed on DTC patients were for management of PD. Improved preoperative CT assessments and initial surgery, based on the information of clinico-radiological characteristics, are required in the care of DTC patients.

[Follow-up of differentiated thyroid cancer]

The management of differentiated thyroid carcinoma has shown considerable changes in recent years, moving away from a fixed therapy regimen towards individual treatment strategies. The aim of our work (literature research) is to present current developments in the follow-up of differentiated thyroid cancer.For the management of individual follow-up, an initial evaluation and, at later time points, the re-evaluation of the risk of recurrence is crucial. The performance of I-131-diagnostics after radioiodine therapy can provide essential information and can be seen as a survey of a new baseline situation, in order to be able to draw a comparison in case of a rising Thyreoglobulin (Tg).The measurement of Tg with a highly sensitive assays shows a high negative predictive value. Negative Tg measurements with these assays seem to indicate complete remission even with Tg antibodies being present. An increasing Tg value in follow-up implies further diagnostic work-up, primarily neck ultrasonography. Sonographically suspicious findings should be subjected to fine needle biopsy, whereby in addition to cytological processing, determination of Tg from the sample can be recommended. If the suspicious lesion cannot be displayed sonographically and Tg values keep rising, computed tomography (CT) and magnetic resonance imaging (MRI) of the neck region can provide further information. FDG-PET/CT has also shown an excellent performance in this setting.The previously fixed therapy regimen has been realigned towards an individual treatment management. Current studies and guidelines lead to a repetitive recurrence risk evaluation and the adjustment of the aftercare planning to the individual risks with appropriately selected examination methods and personalized intervals of assessment.

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.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Quality of Life in Papillary Thyroid Microcarcinoma Patients Undergoing Radiofrequency Ablation or Surgery: A Comparative Study

Objective: Papillary thyroid microcarcinoma (PTMC) has a good prognosis and a long survival time. Health-related quality of life (HRQoL) is vital for PTMC patients during their survivorship. Ultrasound (US)-guided radiofrequency ablation (RFA), which has high efficacy and safety, is recommended as an alternative treatment to surgery for the patients with low-risk PTMC. However, the assessment of QoL of patients with PTMC has not been specially reported. The purpose of our study was to compare the HRQoL of patients with PTMC who underwent RFA and those who underwent surgery. Methods: From October 2019 to December 2019, 88 PTMC patients were enrolled in our study, including 54 in RFA group and 34 in surgery group. We used three questionnaires which included the 36-item short form health survey (SF-36), thyroid cancer-specific quality of life (THYCA-QOL), and Fear of Progression Questionnaire-Short Form (FoP-Q-SF) for each patient to evaluate their scores of HRQoL. The scores were compared after adjusting for age, sex, medical expense, and follow-up time. Results: According to the SF-36, the scores of the domain for the role limitation due to physical problems and emotional problems (RP, RE) as well as Physical Component Summary (PCS) showed a significant negative linear association between the RFA group and surgery group: RP coefficient [coef]-22.613 [confidence interval (CI) -33.504 to -11.723], p < 0.001, RE (coef: -21.901 [CI -36.737 to -7.064], p = 0.004), and PCS (coef: -8.312 [CI -13.694 to -2.930], p = 0.003). The THYCA-QOL showed that the scores of the surgery group were higher than that of the RFA group regarding scars (coef: 10.246 [CI 1.330 to 19.162], p = 0.025 according to the multivariate analysis), suggesting a higher level of complaint in the surgery group. There was no statistically significant difference in the scores of FoP-Q-SF between the two groups. Conclusions: In patients with PTMC, US-guided RFA offers advantage over surgery in terms of HRQoL, which supports the role of RFA as an alternative strategy to surgery.

Association of Radioactive Iodine Administration After Reoperation With Outcomes Among Patients With Recurrent or Persistent Papillary Thyroid Cancer

Importance

One-third of patients with papillary thyroid cancer (PTC) develop persistent or recurrent disease after initial therapy. Most patients with persistent or recurrent disease undergo reoperation, but the role of treatment with radioactive iodine (RAI) after reoperation is unclear.

Objective

To determine whether receipt of RAI after reoperation for recurrent PTC is associated with improved outcomes.

Design, Setting, and Participants

This retrospective cohort study included electronic health record data from 102 patients who underwent neck reoperation for persistent or recurrent PTC at a tertiary referral center from April 2006 to January 2016; 50 patients received RAI after reoperation, and 52 did not receive RAI after reoperation. Data analysis was performed from September 1, 2017, to December 1, 2017.

Main Outcomes and Measures

Suppressed thyroglobulin (Tg) levels were compared between patients who underwent reoperation and received RAI and patients who underwent reoperation without receipt of RAI at the following time points: before reoperation (Tg0), after reoperation (Tg1), and after RAI or a comparable time interval among patients whose cases were managed without RAI (Tg2). Outcomes were biochemical response and structural recurrence after reoperation.

Results

The cohort comprised 102 patients who underwent neck reoperation for persistent or recurrent PTC (median age, 44 years [interquartile range, 33-54 years; SD, 14 years]; 67 [66%] female), 50 of whom received treatment with RAI after reoperation. Clinicopathologic characteristics of the patients at the time of the initial surgical procedure were similar between the reoperation with RAI group and the reoperation without RAI group with the exception of tumor (T) stage (T3 and T4, 28 of 50 [56%] vs 19 of 52 [37%]). Although median Tg levels were similar between the reoperation with RAI group and the reoperation without RAI group (Tg0, 3.3 ng/mL vs 2.4 ng/mL; Tg1, 0.6 ng/mL vs 0.2 ng/mL; and Tg2, 0.5 ng/mL vs 0.2 ng/mL; all differences were nonsignificant), the rate of excellent response at Tg1 was lower in the reoperation with RAI group (4 of 33 [12%] vs 24 of 51 [47%]; P = .007). Structural recurrence after reoperation occurred in 18 of 50 patients (36%) in the reoperation with RAI group and 10 of 52 patients (19%) in the reoperation without RAI group. In multivariable analysis accounting for clinicopathologic characteristics and Tg0, receipt of RAI after reoperation was not associated with the rate of a second structural recurrence. In subset analyses limited to patients with incomplete response to reoperation and patients with T3 or T4 tumors, no association between receipt of RAI and the risk of a second recurrence was found.

Conclusions and Relevance

Patients who received RAI after reoperation had outcomes similar to those in patients who underwent reoperation alone. RAI after reoperation was not associated with a significant clinical benefit in this limited series. Larger multicenter studies are required to determine whether receipt of RAI after reoperation improves outcomes among patients with recurrent PTC.

Recurrent Papillary Thyroid Carcinoma to the Cervical Lymph Nodes: Outcomes of Compartment-Oriented Lymph Node Resection

INTRODUCTION

Recurrence of papillary thyroid carcinoma after initial treatment is challenging. Surgical reintervention is recommended, but cure after surgery in uncertain and surgical morbidity may be high. This study evaluates the effect of compartment-oriented lymph node dissection (LND) on clinical and biochemical cure rate as well as the related complications.

PATIENTS AND METHODS

All patients who underwent LND for recurrent papillary thyroid carcinoma between 2000 and 2015 were included. Demography, the extent of the initial surgery, usage of ¹³¹I, the pattern of recurrence, diagnosis, details of the surgical reintervention, histological findings, surgical morbidity, and clinical and biochemical outcomes were analyzed.

RESULTS

There were 11 (12.7%) males and 75 (87.2%) females with a mean age of 42.8 ± 14.6 years. Seventy-seven patients had undergone total thyroidectomy and in 67 (77.9%) some type of LN resection. In 76 (88.3%), ¹³¹I was administered after the initial surgery. We localized suspicious lymph nodes by US in all patients, and metastases were documented before surgery by FNA in 63. Seven (8.13%) patients underwent central LND, 63 (73.2%) lateral LND and 16 (18.6%) both, central and lateral LND. Major complications occurred in 6 patients (6.9%). Sixty-two (72.0%) patients received ¹³¹I after surgery. A second surgical re-exploration was performed in 30 (34.8%) patients, and 7 patients required 3 or more additional LND. In a mean follow-up of 59.4 ± 39 months, 51 (59.3%) patients are clinically, radiologically and biochemically free of disease.

CONCLUSIONS

In this series, compartment-oriented lymph node resection of recurrent papillary thyroid carcinoma leads to a final clinical and biochemical disease-free status of 59.3% with 6.9% of major complications.

Identifying risk factors of recurrence for clinically node negative papillary thyroid carcinoma with pathologic N1a

Background

Whether or not to perform prophylactic central lymph node dissection (CLND) in the case of clinically node-negative papillary thyroid cancer (PTC) is controversial. The purpose of this study was to investigate the risk factors for recurrence in clinically node-negative PTC patients who underwent total thyroidectomy plus bilateral central neck dissection and was verified pathologic N1a.

Methods

We retrospectively reviewed the medical records of 1082 PTC patients who underwent total thyroidectomy and prophylactic bilateral CLND between January 2004 and December 2012. We used Cox-proportional hazard regression analyses in order to explore potential predictive factors for recurrence.

Results

During a median follow-up (range) of 78 (12–158) months, recurrence occurred in 62 (5.7%) patients. Main tumor size more than 1 cm, gross extrathyroidal extension (ETE), positive lymph node (LN) more than 3, and LN ratio > 0.5 were all significantly associated with recurrence according to univariate analysis. In model I multivariate analysis (tumor size, gross ETE, LN ratio), LN ratio > 5 (hazards ratio [HR], 4.794; 95% confidence interval [CI], 2.674–8.595; p < 0.001) was found to be predictive of recurrence. Gross ETE (HR, 1.794; 95% CI, 1.024–3.143; p = 0.041) and positive LN more than 3 (HR, 2.505; 95% CI, 1.513–4.146; p < 0.001) were predictors for recurrence in model II multivariate analysis (tumor size, gross ETE, the number of positive LN).

Conclusions

We recommend that surgeons try to focus completely on performing prophylactic CLND for patients with suspicious gross ETE during preoperative evaluation. Close monitoring and thorough management are needed for clinically node-negative PTC patients with LN ratio of more than 0.5 and more than 3 positive LN in the central compartment.

The role of prophylactic central compartment lymph node dissection in elderly patients with differentiated thyroid cancer: a multicentric study

BACKGROUND

Prophylactic central neck lymph-nodes dissection is still a topic of major debate in Literature. There is a lack of randomized controlled trials proving advantages in its application in terms of overall survival and local recurrence. Due to the recent rapid increase of elderly population, differentiated tumor carcinoma diagnosis increased in patients over 65 years old. The aim of this study was to compare recurrence rate, complications rate and histological features of tumors in elderly population.

METHODS

A retrospective study was carried out collecting data from 371 patients with differentiated thyroid cancer without clinical evidence of lymph-nodes involvement in three Italian referral centers from 2005 to 2015. All patients were aged ≥ 65 years and were divided in two groups based on the performed surgery (total thyroidectomy alone or associated with central lymph-nodes dissection). Moreover, patients were stratified according to the age between 65 and 74 years old and over 75 years old.

RESULTS

Total thyroidectomy alone was performed in 184 patients (group A) and total thyroidectomy with prophylactic central neck dissection was performed in 187 cases (group B). There was a statistically significant difference in complications between the groups in terms of neck hematoma (0.5% group A vs 3.7% group B), temporary hypoparathyroidism (11.4% group A vs 21.4% group B), and temporary unilateral recurrent nerve injury (1.5% group A vs 6.4% group B). Lymph nodes recurrence rate was 9.2% in group A and 8.5% in group B, with no statistically significant difference. There was a statistically significant difference in patients over 75 years old in terms of temporary hypoparathyroidism (24% group A vs 11% group B), permanent hypoparathyroidism (2,7% group A vs 0,3% group B) and recurrent nerve injury (9,5% group A vs 2% group B).

CONCLUSIONS

The role of prophylactic central neck dissection is still controversial, especially in elderly patients, and an aggressive surgical approach should be carefully evaluated. The Authors reported a similar low recurrence rate between total thyroidectomy and total thyroidectomy associated with prophylactic central neck dissection, with increased postoperative complications in the lymphadenectomy group and in patients over 75 years old, advocating a tailored surgical approach in elderly population.

Application of deep learning to the diagnosis of cervical lymph node metastasis from thyroid cancer with CT

PURPOSE

To develop a deep learning-based computer-aided diagnosis (CAD) system for use in the CT diagnosis of cervical lymph node metastasis (LNM) in patients with thyroid cancer.

METHODS

A total of 995 axial CT images that included benign (n = 647) and malignant (n = 348) lymph nodes were collected from 202 patients with thyroid cancer who underwent CT for surgical planning between July 2017 and January 2018. The datasets were randomly split into training (79.0%), validation (10.5%), and test (10.5%) datasets. Eight deep convolutional neural network (CNN) models were used to classify the images into metastatic or benign lymph nodes. Pretrained networks were used on the ImageNet and the best-performing algorithm was selected. Class-specific discriminative regions were visualized with attention heatmap using a global average pooling method.

RESULTS

The area under the ROC curve (AUROC) for the tested algorithms ranged from 0.909 to 0.953. The sensitivity, specificity, and accuracy of the best-performing algorithm were all 90.4%, respectively. Attention heatmap highlighted important subregions for further clinical review.

CONCLUSION

A deep learning-based CAD system could accurately classify cervical LNM in patients with thyroid cancer on preoperative CT with an AUROC of 0.953. Whether this approach has clinical utility will require evaluation in a clinical setting.

KEY POINTS

• A deep learning-based CAD system could accurately classify cervical lymph node metastasis. The AUROC for the eight tested algorithms ranged from 0.909 to 0.953. • Of the eight models, the ResNet50 algorithm was the best-performing model for the validation dataset with 0.953 AUROC. The sensitivity, specificity, and accuracy of the ResNet50 model were all 90.4%, respectively, in the test dataset. • Based on its high accuracy of 90.4%, we consider that this model may be useful in a clinical setting to detect LNM on preoperative CT in patients with thyroid cancer.

Long-Term Efficacy of Lymph Node Reoperation for Persistent Papillary Thyroid Cancer: 13-Year Follow-Up

BACKGROUND

Current recommendations for persistent or recurrent locoregional papillary thyroid cancer (PTC) include consideration of surgical resection versus active surveillance. The purpose of this study is to determine long-term outcomes after surgical resection of recurrent or persistent metastatic PTC in cervical lymph nodes after failure of initial surgery and radioactive iodine therapy using newer validated clinical outcomes measures.

METHODS

Outcomes of 70 patients who underwent cervical lymphadenectomy (n = 110) from 1999 to 2013 for recurrent or persistent locoregional PTC metastases were reviewed. Measures included biochemical remission (BCR) based on Tg levels, American Thyroid Association classifications for response to treatment [biochemical incomplete response (BIR), structural incomplete response (SIR), indeterminate response (IR), and excellent response (ER)], need for reoperation, surgical complications, disease progression, and death.

RESULTS

The median follow-up was 13.1 years, with only two additional reoperations since 2010, one of which had no metastasis on pathology with the other developing anaplastic thyroid cancer in background PTC. ER was achieved in 31 (44%) patients, all of whom remained in ER at time of last follow-up (median 14.1 years). There were no structural recurrences in patients with persistent BIR or IR after reoperation. Patients with SIR had stable disease, except for one who died due to anaplastic thyroid cancer.

CONCLUSIONS

Patients who achieved ER after reoperation had no need for further treatment. Patients with persistent detectable Tg levels after reoperation rarely developed structural recurrence. ATA outcomes can be safely used to guide treatment decisions over a decade after reoperation for PTC.

Re-treatment With Adjuvant Radioactive Iodine Does Not Improve Recurrence-Free Survival of Patients With Differentiated Thyroid Cancer

Introduction: Loco regional persistence or recurrence of differentiated thyroid cancer (DTC) is frequent despite initial thyroidectomy and radioactive iodine therapy (RAI). The aim of this study was to analyze the impact of a complementary adjuvant RAI (Ad-RAI) on disease recurrence following re-operation on patients with locally persistent or recurrent DTC. Patients and Methods: A retrospective study of 85 patients with DTC was conducted. All patients were initially treated with total thyroidectomy and RAI, and re-operated for a locally persistent or recurrent disease. Propensity score was calculated to predict the impact of Ad-RAI on survival after reoperation, and to reduce the bias of the limited sample size and the prognostic tests. Results: 49 (58%) patients were re-treated with Ad-RAI after re-operation while 36 (42%) were only followed up. Disease recurrence after re-treatment (re-operation ± Ad-RAI) was detected in 31 patients (36.5%). In multivariate analysis, age >55 years (HR: 3.9 [1.6; 9.5]; p < 0.00001) was the main poor prognostic factor for recurrence-free survival. Three parameters independently influenced the decision to administer ad-RAI: low number of previous RAI administrations, Nx before re-operation, and pTg > 30 μg/l. These parameters were incorporated in the Propensity score calculation. If ad-RAI tended to improve recurrence-free survival (median survival 17.4 vs. 10.9 months), adjustment using the Propensity score removed any difference between the groups (p = 0.54), confirming the limited value of ad-RAI. Conclusion: In patients with locally persistent or recurrent DTC, age is the main independent prognostic factor. Adjuvant RAI does not improve recurrence-free survival of DTC patients.

Diagnostic value of computed tomography combined with ultrasonography in detecting cervical recurrence in patients with thyroid cancer

BACKGROUND

To determine the diagnostic role of CT added to ultrasound for the diagnosis of recurrent differentiated thyroid cancer (DTC) and to evaluate potential benefits for patients.

METHODS

A total of 193 patients with recurrent DTC were retrospectively included. The diagnostic performances of ultrasound and combination of ultrasound and CT (ultrasound/CT) in detecting recurrence were compared. Benefits of CT were assessed based on the presence of any recurrence detected only with additional CT.

RESULTS

In detecting cervical recurrence, ultrasound/CT showed higher sensitivity (P = .001) and lower specificity (P < .001) than ultrasound alone, overall resulting in higher area under the curve (P < .001). Seventy-nine patients (40.9%) benefited from additional CT in detecting recurrence.

CONCLUSION

For reoperation of cervical recurrence in patients with DTC, addition of CT to ultrasound offers better surgical planning by enhancing detection of recurrent cancers that were overlooked with ultrasound alone.

Persistent/Recurrent Differentiated Thyroid Cancer: Clinical and Radiological Characteristics of Persistent Disease and Clinical Recurrence Based on Computed Tomography Analysis

BACKGROUND

The natural course of persistent/recurrent differentiated thyroid cancer (DTC) has not been fully elucidated. The purpose of this study was to assess the relative incidence and clinico-radiological characteristics of persistent disease and clinical recurrence based on computed tomography (CT) analysis in patients with persistent/recurrent DTC.

METHODS

From January 2005 to December 2016, this retrospective study included 107 patients (M:F = 28:79; M_age = 53.5 years) with surgically proven cervical locoregional recurrence of DTC. Two neck CT examinations (median interval 1.92 years; range 0.17-7.58 years) before the last thyroid cancer surgery within the study period were reevaluated. Based on the presence of the lesion on the first CT and its progression on the second CT, the locoregional recurrence was classified into the following categories: stable persistence (decrease, no change, or increase by <2 mm in short dimension on the second CT), progressive persistence (increase by ≥2 mm), and clinical recurrence (newly appeared on the second CT). Clinical and radiological characteristics of the three groups were compared using univariate and multivariate logistic regression analyses.

RESULTS

The relative incidences of stable persistence, progressive persistence, and clinical recurrence were 56.1% (60/107), 15.0% (16/107), and 29.0% (31/107), respectively. Multivariate analysis between the clinical recurrence (29.0%) and persistence (71.0%) groups revealed various independent factors for prediction of clinical recurrence. These included longer interval between the two CT examinations (median 2.67 vs. 1.79 years; p = 0.021), a smaller number of thyroid surgeries (1.16 ± 0.45 vs. 1.55 ± 0.81; p = 0.002), and a history of neck dissection at the location of the largest locoregional recurrence (70.0% vs. 31.4%; p < 0.001). There was no significant independent factor for differentiation between the stable persistence (78.9%; 60/76) and progressive persistence (21.1%; 16/76) groups. The results may have been influenced by selection bias because this study included only surgically proven cases.

CONCLUSIONS

With regard to cervical locoregional recurrence of DTC, active surveillance may be favored because more than a half of the cases are structurally persistent and stable. However, meticulous evaluation is necessary to detect progressive persistence and clinical recurrence, considering various clinical factors.

Treatment of lateral neck papillary thyroid carcinoma recurrence after selective lateral neck dissection

BACKGROUND

There is a paucity of data regarding optimal treatment options and outcomes for recurrent disease after lateral neck dissection in patients with papillary thyroid carcinoma.

METHODS

Retrospective review of patients who underwent either percutaneous ethanol injection or surgery for first-time ipsilateral recurrences after ipsilateral lateral neck dissection for papillary thyroid carcinoma was performed.

RESULTS

Follow-up data were available for 54 patients with recurrences in 57 lateral necks treated by either percutaneous ethanol injection (n = 32) or surgery (n = 25). Tumor burden at the time of lateral neck recurrence differed between the groups including the largest lymph node diameter (mean: 13 mm vs 18 mm, P < .01) and the mean number of metastatic lymph nodes identified on ultrasound (1.3 vs 1.9, P = .04). Each modality alone achieved similar estimated rates of disease control at 36 months (75% for percutaneous ethanol injection and 74% for surgery, P = .8) with similar number of reinterventions (1.8 for percutaneous ethanol injection, 1.6 for surgery, P = .6).

CONCLUSIONS

Both ethanol ablation and surgery can achieve disease control in the majority of patients with recurrences after ipsilateral lateral neck dissection for papillary thyroid carcinoma. Ethanol ablation, when used for treatment of a single small lymph node, can result in outcomes that are similar to reoperative surgery for larger and multiple lymph nodes.

Management and outcome of clinically evident neck recurrence in patients with papillary thyroid cancer

BACKGROUND

The aim of this study was to report our incidence of clinically evident neck recurrence, salvage neck management and subsequent outcomes in patients with papillary thyroid cancer. This is important to know so that patients with thyroid cancer can be properly counselled about the implications of recurrent disease and subsequent outcome.

METHODS

An institutional database of 3664 patients with thyroid cancer operated between 1986 and 2010 was reviewed. Patients with nonpapillary histology and gross residual disease and those with distant metastases at presentation or distant metastases prior to nodal recurrence were excluded from the study. Of these, 99 (3.0%) patients developed clinically evident nodal recurrence. Details of recurrence and subsequent therapy were recorded for each patient. Subsequent disease-specific survival (sDSS), distant recurrence-free survival (sDRFS) and nodal recurrence-free survival (sNRFS) were determined from the date of first nodal recurrence using the Kaplan-Meier method.

RESULTS

Of the 99 patients, 59% were female and 41% male. The median age was 41 years (range 5-91). The majority of patients had pT3/4 primary tumours (63%) and were pN+ (78%) at initial presentation. The median time to clinically evident nodal recurrence was 28 months (range: 3-264). Nodal recurrence occurred in the central neck in 15 (15%) patients, lateral neck in 74 (75%) patients and both in 10 (10%) patients. After salvage treatment, the 5-year sDSS was 97.4% from time of nodal recurrence. The 5-year sDRFS and sNRFS were 89.2% and 93.7%, respectively.

CONCLUSION

In our series, isolated clinically evident nodal recurrence occurred in 3.0% of patients. Such patients are successfully salvaged with surgery and adjuvant therapy with sDSS of 97.4% at 5 years.

Impact of Radioguided Occult Lesion Localization (ROLL) in the management of cervical recurrences from differentiated thyroid cancer

BACKGROUND

Surgery is the elective treatment for cervical relapse from differentiated thyroid cancer (DTC) but it is technically challenging, with risk of failure and morbidity. We explored the feasibility and the efficacy of Radioguided Occult Lesion Localization (ROLL) with intratumoral 99mTc radiolabeled human albumin macroaggregates ([99mTc]MAA) injection in this setting.

METHODS

Fifteen patients who underwent ROLL by ultrasonography (US)-guided intratumoral injection of [99mTc]MAA between December 2013 and October 2016 for DTC recurrence were considered for this study. An hand-held gamma-probe was employed for intrasurgical lesion detection. Mini-invasive ROLL-guided excision for soft tissue recurrence and ROLL-assisted modified radical neck dissection for lymph-node metastases were performed respectively.

RESULTS

DTC recurrence was located in loco-regional lymph-nodes (n=8 patients) and in thyroid bed (n=7 patients). A total of 27 lesions was identified and injected before surgery. On a total of 124 lesions resected, histology showed 38 DTC metastases. In particular, 26 out of 27 lesions injected with [99mTc]MAA were correctly detected intra-operatively and resected without surgical complications. Ten patients received subsequent radioactive iodine (RAI) treatment to verify the complete recurrence resection. At a median follow-up of 16 months patients were classified in complete response (n=4), biochemical incomplete response (n=3), indeterminate response (n=1) with no evidence of structural disease. The remaining 7 patients were classified as structural incomplete response for cervical persistent disease (n=2), for cervical recurrence (n=2) and for both cervical and lung metastases progression (n=3).

CONCLUSIONS

ROLL is a simple and safe procedure in the surgical management of DTC loco-regional relapse.

Evaluating the effectiveness of prophylactic central neck dissection with total thyroidectomy for cN0 papillary thyroid carcinoma: An updated meta-analysis

BACKGROUND

The effectiveness of prophylactic central neck dissection (pCND) following total thyroidectomy (TT) in patients with clinical node-negative (cN0) papillary thyroid carcinoma (PTC) is still controversial. The aim of this meta-analysis is to evaluate the outcome of pCND and to provide quantitative evidence.

METHOD

A detailed literature search of PubMed, EMBASE, ClinicalTrails.gov and Cochrane Library electronic databases for articles published up to October 2016 was carried out. This meta-analysis was performed by the random method (Mantel-Haenszel) model. Locoregional recurrence (LRR) and surgical complications were analyzed.

RESULTS

Twenty-two studies comparing pCND + TT (combined) and TT alone in cN0 PTC patients were analyzed. A total of 6930 cases were enrolled, including 2381 cases in the combined group and 4009 cases in the TT-alone group. Compared with TT alone, patients in the combined group showed a significantly lower rate of overall LRR (OR = 0.66, 95% CI = 0.48-0.89) and central compartment recurrence (OR = 0.40, 95% CI = 0.22-0.73). There was no statistical difference in the rate of lateral compartment recurrence. However, the combined group showed a significantly higher rate of temporary and permanent hypoparathyroidism (OR = 2.28, 95% CI = 1.92-2.27/OR = 1.84, 95% CI = 1.15-2.95) and temporary recurrent laryngeal nerve injury (LNR) (OR = 1.53, 95% CI = 1.08-2.16). There was no statistical difference in the rate of permanent LNR, hematoma, hemorrhage or wound infection.

CONCLUSIONS

This meta-analysis revealed that pCND with TT was a significantly efficient way to reduce the risk of LRR. However, pCND + TT increased the incidence rate of temporary and permanent hypoparathyroidism and temporary LNR.

Significance of Size of Persistent/Recurrent Central Nodal Disease on Surgical Morbidity and Response to Therapy in Reoperative Neck Dissection for Papillary Thyroid Carcinoma

BACKGROUND

To balance the risk of disease progression, morbidity, and efficacy of reoperative central neck dissection (RCND) in papillary thyroid carcinoma, the latest clinical guidelines recommend early surgery over surveillance when the largest diseased node is >8 mm in its smallest dimension. However, the evidence remains scarce. To determine an appropriate size for first-time RCND, the relationship between size of largest diseased central node, morbidity, and response-to-therapy following RCND was examined.

METHODS

A total of 130 patients who underwent RCND following initial surgery for persistent/recurrent nodal disease were reviewed. Patients with largest diseased central node measured preoperatively by ultrasonography were included. Eligible patients were categorized into three groups: largest central node <10 mm (group I), 10-15 mm (group II), and >15 mm (group III). Surgical morbidity and response to therapy at one year after RCND were compared between groups. To evaluate biochemical response, patients with structural incompleteness were excluded.

RESULTS

Group III not only had significantly more high-risk tumors (by American Thyroid Association risk stratification) at initial therapy (64.5% vs. 44.4%, respectively; p = 0.038), but this group also a higher risk of extranodal extension (35.5% vs. 16.0%; p = 0.055), recurrent laryngeal nerve involvement (19.4% vs. 0.0%; p < 0.001), incomplete surgical resection (48.4% vs. 7.4%; p < 0.001), new-onset vocal cord paresis (16.7% vs. 2.5%; p = 0.017), overall surgical morbidity (22.6% vs. 7.4%; p = 0.021), and biochemical incompleteness (80.6% vs. 67.9%; p = 0.004) than groups I and II combined did. However, overall morbidity did not differ between groups I and II (5.7% vs. 8.7%; p = 0.694). After adjusting for American Thyroid Association risk stratification, only the size of the largest diseased central node ≥15 mm (odds ratio = 7.256 [confidence interval 1.302-40.434], p = 0.001) was an independent risk factor for biochemical incompleteness following RCND.

CONCLUSIONS

Patients with larger diseased central node(s) had a significantly higher risk of local invasion, surgical morbidity, and biochemical incompleteness. Relative to nodal size <10 mm, size >15 mm in the largest disease central node was an independent risk factor for incomplete biochemical response, while nodal size 10-15 mm was not. These findings imply that the recommended threshold of 8 mm might be too stringent and could be raised to 15 mm without increasing the surgical morbidity from RCND.

Risk Stratification of Neck Lesions Detected Sonographically During the Follow-Up of Differentiated Thyroid Cancer

CONTEXT

The European Thyroid Association (ETA) has classified posttreatment cervical ultrasound findings in thyroid cancer patients based on their association with disease persistence/recurrence.

OBJECTIVE

The objective of the study was to assess this classification's ability to predict the growth and persistence of such lesions during active posttreatment surveillance of patients with differentiated thyroid cancer (DTC).

DESIGN

This was a retrospective, observational study.

SETTING

The study was conducted at a thyroid cancer center in a large Italian teaching hospital.

PATIENTS

Center referrals (2005-2014) were reviewed and patients selected with pathologically-confirmed DTC; total thyroidectomy, with or without neck dissection and/or radioiodine remnant ablation; abnormal findings on two or more consecutive posttreatment neck sonograms; and subsequent follow-up consisting of active surveillance. Baseline ultrasound abnormalities (thyroid bed masses, lymph nodes) were classified according to the ETA system. Patients were divided into group S (those with one or more lesions classified as suspicious) and group I (indeterminate lesions only). We recorded baseline and follow-up clinical data through June 30, 2015.

MAIN OUTCOMES

The main outcomes were patients with growth (>3 mm, largest diameter) of one or more lesions during follow-up and patients with one or more persistent lesions at the final visit.

RESULTS

The cohort included 58 of the 637 DTC cases screened (9%). A total of 113 lesions were followed up (18 thyroid bed masses, 95 lymph nodes). During surveillance (median 3.7 y), group I had significantly lower rates than group S of lesion growth (8% vs 36%, P = .01) and persistence (64% vs 97%, P = .014). The median time to scan normalization was 2.9 years.

CONCLUSIONS

The ETA's evidence-based classification of sonographically detected neck abnormalities can help identify papillary thyroid cancer patients eligible for more relaxed follow-up.

Engineering Multi-Walled Carbon Nanotube Therapeutic Bionanofluids to Selectively Target Papillary Thyroid Cancer Cells

BACKGROUND

The incidence of papillary thyroid carcinoma (PTC) has risen steadily over the past few decades as well as the recurrence rates. It has been proposed that targeted ablative physical therapy could be a therapeutic modality in thyroid cancer. Targeted bio-affinity functionalized multi-walled carbon nanotubes (BioNanofluid) act locally, to efficiently convert external light energy to heat thereby specifically killing cancer cells. This may represent a promising new cancer therapeutic modality, advancing beyond conventional laser ablation and other nanoparticle approaches.

METHODS

Thyroid Stimulating Hormone Receptor (TSHR) was selected as a target for PTC cells, due to its wide expression. Either TSHR antibodies or Thyrogen or purified TSH (Thyrotropin) were chemically conjugated to our functionalized Bionanofluid. A diode laser system (532 nm) was used to illuminate a PTC cell line for set exposure times. Cell death was assessed using Trypan Blue staining.

RESULTS

TSHR-targeted BioNanofluids were capable of selectively ablating BCPAP, a TSHR-positive PTC cell line, while not TSHR-null NSC-34 cells. We determined that a 2:1 BCPAP cell:α-TSHR-BioNanofluid conjugate ratio and a 30 second laser exposure killed approximately 60% of the BCPAP cells, while 65% and >70% of cells were ablated using Thyrotropin- and Thyrogen-BioNanofluid conjugates, respectively. Furthermore, minimal non-targeted killing was observed using selective controls.

CONCLUSION

A BioNanofluid platform offering a potential therapeutic path for papillary thyroid cancer has been investigated, with our in vitro results suggesting the development of a potent and rapid method of selective cancer cell killing. Therefore, BioNanofluid treatment emphasizes the need for new technology to treat patients with local recurrence and metastatic disease who are currently undergoing either re-operative neck explorations, repeated administration of radioactive iodine and as a last resort external beam radiation or chemotherapy, with fewer side effects and improved quality of life.

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.

Contemporary Management of Recurrent Nodal Disease in Differentiated Thyroid Carcinoma

Differentiated thyroid carcinoma (DTC) comprises over 90% of thyroid tumors and includes papillary and follicular carcinomas. Patients with DTC have an excellent prognosis, with a 10-year survival rate of over 90%. However, the risk of recurrent tumor ranges between 5% and 30% within 10 years of the initial diagnosis. Cervical lymph node disease accounts for the majority of recurrences and in most cases is detected during follow-up by ultrasound or elevated levels of serum thyroglobulin. Recurrent disease is accompanied by increased morbidity. The mainstay of treatment of nodal recurrence is surgical management. We provide an overview of the literature addressing surgical management of recurrent or persistent lymph node disease in patients with DTC.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.