Clinical characteristics of papillary thyroid microcarcinoma less than or equal to 5 mm on ultrasonography

Combining Clinicopathologic and Ultrasonic Features for Predicting Skip Metastasis of Lateral Lymph Nodes in Papillary Thyroid Carcinoma

Background

Skip metastasis, regarded as lateral lymph node metastasis (LLNM) without involving the central lymph node metastasis (CLNM), in papillary thyroid carcinoma (PTC) patients is commonly unpredictable. The purpose of the present research was to investigate the independent risk factors of skip metastasis in patients with PTC.

Methods and Materials

In the present research, 228 consecutive PTC patients who experienced total thyroidectomy coupled with central and lateral lymph node dissection from May 2020 to September 2022 at the Affiliated hospital of Jiangsu University were included in our research. Univariate and multivariate analysis were then applied to investigate the risk factors of skip metastasis in patients with PTC. Furthermore, a predictive model of skip metastasis was then constructed based on risk factors.

Results

The skip metastasis rate was 11.8% (27/228) in the current research. After the univariate and multivariate analysis, tumor size ≤ 10 mm, unilaterality, microcalcification, and upper tumor location were determined to be predictive factors of skip metastasis. The risk score of skip metastasis was calculated: risk score = 1.229 × (if tumor nodule ≤ 10mm) + 1.518 × (if unilaterality nodule) + 1.074 × (if microcalcification in nodule) + 2.332 × (if nodule in upper location).

Conclusion

Tumor size ≤ 10 mm, unilaterality, microcalcification, and upper tumor location can increase the occurrence of skip metastasis in patients with PTC, which is expected to provide useful information to guide the suitable intraoperative window.

The incidence and features of Delphian lymph node involvement in patients with papillary thyroid carcinoma

Introduction

In papillary thyroid cancer patients, the extent of dissection is still a matter of debate. Evaluating Delphian lymph nodes (DLNs) during the surgery has been speculated as a valuable tool to determine the extent of dissection. Herein, we aimed to evaluate the incidence and features of DLNs involvement in patients with papillary thyroid carcinoma.

Method

We conducted this cross-sectional study among surgical cases of papillary thyroid cancer. Patients were divided based on their DLNs involvement status. Their age, gender, location of the mass, lymphatic involvement, tumor size, tumor characteristics, pathology report, and operation note features were compared between the two groups. Definitive pathology slides of the patients were evaluated regarding DLN features.

Results

Of the 61 patients (mean age: 38.2 ± 12.0), 45 (73.8%) were females. In 13 (21.3%) patients, DLNs involvement was reported. A statistically significant relationship was noted between DLNs involvement and other lymph nodes' involvement on the same side of the mass (P < 0.001), the opposite side (P = 0.041), and also central lymph nodes (P < 0.001). Vascular invasion was also significantly higher among patients with DLNs involvement (P = 0.012).

Conclusion

Since DLNs involvement is significantly associated with extensive nodal involvement, intraoperative evaluation of DLNs is recommended to establish the extent to which dissection should be performed.

Differences in the clinical characteristics of papillary thyroid microcarcinoma located in the isthmus ≤5 mm and >5mm in diameter

Background

The optimal treatment of papillary thyroid microcarcinomas (PTMCs) located in the isthmus (iPTMCs) is still controversial. The purpose of this study was to compare the clinicopathologic features of patients with iPTMCs ≤5 mm and >5 mm in diameter after total thyroidectomy, and to identify the risk factors for recurrence in patients with iPTMCs.

Methods

A total of 102 iPTMC patients who underwent total thyroidectomy were reviewed retrospectively. The clinicopathologic characteristics of iPTMCs ≤5 mm group (n = 29) have been compared with a group >5 mm (n = 73). Univariate and multivariate Cox proportional hazard models served to identify risk factors associated with recurrence-free survival (RFS).

Results

Gender (p = 0.033), multifocality (p = 0.041), and central lymph node metastasis (CLNM) (p = 0.009) of patients in the ≤5 mm and >5 mm groups differed significantly. iPTMC patients with age <55 years, male, multiple tumor, and extrathyroidal extension showed comparatively more frequent of CLNM in >5 mm groups. Of the 102 patients, nine (8.8%) developed recurrence during follow-up (median: 49.5 months). The patients with recurrences had comparatively high rates of CLNM (p = 0.038), extranodal invasion (p = 0.018), and more MNCND (Metastasis Nodes for Central Neck dissection) (p = 0.020). A cutoff of MNCND >2.46 was established as the most sensitive and specific level for the prediction of recurrence based on receiver operating characteristic (ROC) curve analyses. Multivariate analysis showed that the number of MNCND ≥3 was an independent predictor of poor RFS (p = 0.028).

Conclusion

We have found that the recurrence rates are similar in patients with iPTMCs ≤5 mm and >5 mm. The iPTMCs >5 mm were more likely to be associated with pathological features such as multifocality and CLNM. The male gender, extrathyroidal extension, and CLNM were associated with recurrence of iPTMCs except for tumor size and multifocality. Higher risk of CLNM should be considered in iPTMC >5 mm when it reaches some risk factors. The numbers of MNCND ≥3 may be an independent predictor for recurrence, which could help clinicians for the decision of radioiodine administration and the modulation of follow-up modalities.

Association of sonographic features and clinicopathologic factors of papillary thyroid microcarcinoma for prevalence of lymph node metastasis: a retrospective analysis

OBJECTIVE

The objective of the study was to develop an association between clinicopathologic and sonographic features of patients with papillary thyroid microcarcinoma and the prevalence of lymph node metastasis.

METHODS

Clinicopathologic and sonographic features of 415 patients of papillary thyroid microcarcinoma with (n = 102) or without (n = 313) lymph node metastasis were retrospectively reviewed. The thickness of the lymph node ≥ 6 mm with intra-lymph nodal occupying lesions considered lymph node metastasis. Also, it was considered metastasis if lymph node perfusion or blood flow defect was found with any thickness size. Univariate following multivariate analysis was performed for the prediction of sonographic features and clinicopathologic factors for the prevalence of lymph node metastasis.

RESULTS

Male gender (p = 0.041), age < 45 years (p = 0.042), preoperative calcitonin > 65 pg/ mL (p = 0.039), nodule size > 5 mm in diameter (p = 0.038), bilaterality (p = 0.038), tumor capsular invasion (p = 0.048), cystic change (p = 0.047), and hyper vascularity (p = 0.049) of thyroid nodules were associated with lymph node metastasis. Also, thyroid nodules 5 mm and more in diameter may have high aggressiveness.

CONCLUSION

These data helped the surgeon for individualized treatment in thyroid carcinoma and avoid unnecessary prophylactic surgery of the lymph node.

Identification of biomarkers associated with cervical lymph node metastasis in papillary thyroid carcinoma: Evidence from an integrated bioinformatic analysis

Integrated analysis of accumulated data is an effective way to obtain reliable potential diagnostic molecular of cervical lymph node metastases (LNM) in papillary thyroid carcinoma (PTC). The benefits of prophylactic lymph node dissection (PLND) for these clinically node-negative (cN0) patients remained considerable controversies. Hence, elucidation of the mechanisms of LNM and exploration of potential biomarkers and prognostic indicators are essential for accurate diagnosis of LNM in PTC patients. Up to date, advanced microarray and bioinformatics analysis have advanced an understanding of the molecular mechanisms of disease occurrence and development, which are necessary to explore genetic changes and identify potential diagnostic biomarkers. In present study, we performed a comprehensive analysis of the differential expression, biological functions, and interactions of LNM-related genes. Two publicly available microarray datasets GSE60542 and GSE129562 were available from Gene Expression Omnibus (GEO) database. Differentially expressed genes between clinically node-positive (cN1) and cN0 PTC samples were screened by an integrated analysis of multiple gene expression profile after gene reannotation and batch normalization. Our results identified 48 differentially expressed genes (DEGs) genetically associated with LNM in PTC patients. Gene ontology (GO) analyses revealed the changes in the modules were mostly enriched in the regulation of MHC class II receptor activity, the immune receptor activity, and the peptide antigen binding. Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of DEGs displayed the intestinal immune network for IgA production, staphylococcus aureus infection, and cell adhesion molecules (CAMs). To screen core genes related to LNM of PTC from the protein-protein interaction network, top 10 hub genes were identified with highest scores. Our results help us understand the exact mechanisms underlying the metastasis of cervical LNM in PTC tissues and pave an avenue for the progress of precise medicine for individual patients.

Predictive value of the Delphian lymph node in cervical lymph node metastasis of papillary thyroid carcinoma

INTRODUCTION

Delphian lymph node metastasis (DLNM) has proven to be a risk factor for a poor prognosis in head and neck malignancies. This study aimed to reveal the clinical features and evaluate the predictive value of the Delphian lymph node (DLN) in papillary thyroid carcinoma (PTC) to guide the extent of surgery.

METHODS

Tianjin Medical University Cancer Institute and Hospital pathology database was reviewed from 2017 to 2020, and 516 PTC patients with DLN detection were enrolled. Retrospective analysis was performed, while multivariate analysis was performed to identify the risk factors for DLNM.

RESULTS

Among the 516 PTC patients with DLN detection, the DLN metastasis rate was 25.39% (131/516). Tumor size >1 cm, location in the upper 1/3, central lymph node metastasis (CLNM), lateral lymph node metastasis (LLNM) and lymphovascular invasion were independent risk factors for DLNM. Patients with DLNM had a higher incidence of ipsilateral CLNM, contralateral CLNM (CCLNM) and LLNM, and larger numbers and size of metastatic CLNs than those without DLNM. The incidence of CLNM among cN0 patients with DLNM was higher than that among those without DLNM. The incidence of CCLNM among unilateral cN + patients with DLNM was similarly higher than that among patients without DLNM.

CONCLUSIONS

DLNM indicates a high likelihood and large number of cervical lymph nodes metastases in PTC patients. Surgeons are strongly recommended to detect DLN status during operation by means of frozen pathology, so as to evaluate the possibility of cervical nodal metastasis and decide the appropriate extent of surgery.

Risk factors of metastasis to the lymph nodes posterior to the right recurrent laryngeal nerve in papillary thyroid carcinoma

PURPOSE

To investigate the risk factors of lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in papillary thyroid carcinoma.

METHODS

Clinicopathologic feature data of 427 patients with right or double lobes who underwent surgery between January 2014 to August 2019 in the Department of General Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, were retrospectively analyzed. The risk factors of LN-prRLN metastasis were analyzed by the Chi-squared test and multivariate logistic regression.

RESULTS

LN-prRLN metastasis was detected in 96 patients. Univariate analysis showed that age, right-side tumor diameter, capsular invasion, comorbid adenoma, and VIa compartment LN metastasis were significantly associated with LN-prRLN metastasis (all P < 0.05). Multivariate logistic regression analysis showed that right-side tumor diameter, capsular invasion, and VIa compartment LN metastasis were independent risk factors of LN-prRLN metastasis (all P ≤ 0.001). The receiver operating characteristic curve showed that the cutoff value of the right tumor diameter for predicting LN-prRLN metastasis was 1.25 cm (sensitivity = 0.5, specificity = 0.819, area under the curve = 0.720, P < 0.001).

CONCLUSION

The incidence of LN-prRLN metastasis cannot be ignored, and our findings indicate that prophylactic LN-prRLN dissection should be performed in patients with right-side tumor diameter ≥ 1.25 cm, capsular invasion, and VIa compartment LN metastasis.

Significance of CEP78 and WDR62 gene expressions in differentiated thyroid carcinoma: Possible predictors of lateral lymph node metastasis

OBJECTIVES

This study aimed at investigating the clinical significance of CEP78 and WDR62 in differentiated thyroid carcinoma (DTC). This study also aimed at finding predictors that help in detecting patients with DTC who have high risk for lateral lymph node metastasis (LNM).

METHODS

Quantitative real-time polymerase chain reaction (RT-qPCR) was performed to examine CEP78, and WDR62 mRNA expressions in 40 tissue specimens of DTC, and 40 goiter tissue specimens. Additionally, we reviewed clinical, ultrasound, laboratory, pathological data of patients to analyze the associations between these characteristics and lateral LNM.

RESULTS

Our results demonstrated that relative CEP78 mRNA levels were significantly decreased in thyroid cancer tissues than goiter tissues (P = 0.002). ROC curve analysis confirmed the diagnostic value of CEP78 mRNA expression, providing an AUC equals to 0.698 (95% confidence intervals (CI), 0.583-0.813; P = 0.002). The relative WDR62 mRNA expression was not statistically different in DTC tissues and goiter tissues (P = 0.686). Furthermore, the DTC patients had been included to examine risk factors for lateral LNM. In multivariate analysis, the significant factors for predicting lateral LNM were low CEP78 mRNA expression (cut off value ≤0.54; P = 0.03; OR = 19.62; 95% CI, 1.3-296.23), central LNM (P = 0.011; OR = 33.6; 95% CI, 2.24-503.6) and calcifications (P = 0.023; OR = 27.187; 95% CI, 1.57-469.5).

CONCLUSIONS

CEP78 can be used as a promising molecular biomarker for differentiation between DTC and goiter tissues, in addition it might serve as a predictor of lateral LNM in DTC along with central LNM and calcifications. Unlike CEP78, WDR62 mRNA expression was not statistically different in DTC and goiter.

Risk factors for contralateral central lymph node metastasis in unilateral cN0 papillary thyroid carcinoma: A meta-analysis

BACKGROUND

Central lymph node metastasis(CLNM) is common in papillary thyroid carcinoma(PTC). LNM is related to local recurrence and adverse prognosis. The extent of prophylactic central lymph node dissection(pCLND) is not well defined. We aim to investigate the prevalence and risk factors for contralateral central lymph node metastasis (CCLNM) in unilateral clinical node-negative (cN0) PTC patients to determine the appropriate extent of pCLND.

METHODS

A systematic literature search was performed using PubMed and Embase databases until May 2018. Published studies that estimated the association between clinicopathologic factors and CCLNM were included.

RESULTS

A total of 6 studies involving 1399 patients were included. The prevalence of CCLNM was 10.9% in all patients. The pooled analysis revealed that male gender (pooled OR = 1.67, 95%CI = 1.11-2.53, p = 0.015), age<45years (pooled OR = 1.97, 95%CI = 1.37-2.85, p < 0.001), lymphovasular invasion (pooled OR = 4.23, 95%CI = 2.25-7.98, p < 0.001), extrathyroid invasion (pooled OR = 1.75, 95%CI = 1.08-2.83, p = 0.023), and ipsilateral CLNM (pooled OR = 12.26, 95%CI = 7.27-20.67, p < 0.001) were significant risk factors for CCLNM. While tumor size>1 cm (pooled OR = 3.39, 95%CI = 0.83-13.88, P = 0.090), capsular invasion (pooled OR = 1.28, 95%CI = 0.79-2.06, p = 0.313), extrathyroid extension (pooled OR = 1.49, 95%CI = 0.86-2.56, p = 0.152), and MACIS≥6 (pooled OR = 1.08, 95%CI = 0.51-2.26, p = 0.844) were not significantly associated with CCLNM.

CONCLUSIONS

Our meta-analysis identified that male gender, age<45years, lymphovasular invasion, extrathyroid invasion and ipsilateral CLNM were significant risk factors for CCLNM. These findings may guide the extent of pCLND in unilateral cN0 PTC patients.

Clinicopathological features for predicting central and lateral lymph node metastasis in papillary thyroid microcarcinoma: Analysis of 66 cases that underwent central and lateral lymph node dissection

Currently the surgical approach for papillary thyroid microcarcinoma (PTMC), particularly the range of lymph node dissection, remains controversial. The present study aims to evaluate the risk factors for central and lateral lymph node metastasis (CLNM and LLNM) for appropriate clinical decision of neck lymph node dissection in PTMC. A total of 66 cases of PTMC that underwent unilateral or bilateral lobectomy plus prophylactic cervical lymph node dissection were collected for clinicopathological evaluation, including age, gender, tumor size, subtypes, extrathyroidal invasion, multifocality, calcifications, loss of cellular polarity/cohesiveness (LOP/C) in the invasive front, CLNM and LLNM, and retrospectively analysis. Univariate analysis revealed that LOP/C was significantly associated with CLNM (P=0.001) and LLNM (P<0.0001). The male gender was a risk factor of CLNM (P=0.04), while the age <45 years, tumor size >0.5 cm and multifocality were high-risk factors of LLNM (P=0.022, 0.044 and 0.005, respectively). Multivariable analysis revealed that LOP/C was significantly associated with CLNM [P=0.007, odds ratio (OR)=7.765, 95% confidence interval (CI)=1.773–33.996] and LLNM [P=0.029, OR=5.717, 95% CI=1.190–27.470]. Both multivariable analysis and χ² test revealed that CLNM was another important high-risk factor of LLNM (P=0.021, OR=5.444, 95% CI=1.290–22.969, χ²=17.867, P<0.001). The present study revealed that prophylactic central lymph node dissection is essential for PTMC surgery and that prophylactic lateral lymph node dissection is recommend for patients with LOP/C and CLNM, which can be performed by intraoperative frozen section pathological examination. This must be considered discreetly in the case of patients with age <45 years, tumor size >0.5 cm and multifocal lesions.

Risk Factors for Central Compartment Lymph Node Metastasis in Papillary Thyroid Microcarcinoma: A Meta-Analysis

BACKGROUND

The surgical management of papillary thyroid microcarcinoma (PTMC), especially regarding the necessity of central lymph node dissection (CLND), remains controversial. This meta-analysis was conducted to investigate the clinicopathologic factors predictive of central compartment lymph node metastasis (CLNM) in patients diagnosed with PTMC.

METHODS

PubMed, EMBASE, Ovid, Web of Science, and the Cochrane Library were searched from their inception to September 2013. Published studies that explored the association between clinicopathologic factors and CLNM in PTMC patients were included. From the identified studies, we extracted the number of individuals with or without each risk factor to calculate the CLNM-positive proportions and used fixed/random-effects models for the meta-analyses of overall relative risk (RR). The pooling analysis on the association between CLNM or the different CLNDs and prognosis was also conducted.

RESULTS

A total of 19 eligible studies that included 8345 patients were identified. Three studies did therapeutic CLND, while the other 16 studies performed prophylactic CLND in PTMC patients. Meta-analyses revealed that CLNM was associated with male gender (RR = 1.36; 95 % CI 1.22-1.52, p = 0.001), younger age (<45 years; RR = 1.15; 95 % CI 1.04-1.27, p = 0.006), larger tumor size (>5 mm; RR = 1.51 95 % CI 1.32-1.65, p = 0.001), multifocality (RR = 1.40; 95 % CI 1.27-1.54, p = 0.001), and extrathyroidal extension (RR = 1.81; 95 % CI 1.34-2.43, p = 0.001). Meta-regression analysis indicated that a disparity in the proportion of PTMC patients with CLNM in each study was the main factor resulting in heterogeneity among the 19 studies. In addition, the pooling analyses suggested that CLNM did not significantly predict neck recurrences [hazard ratio (HR) = 0.95, 95 % CI 0.67-1.22, p = 0.054], and the prophylactic CLND group did not improve local control significantly compared to the therapeutic group (RR = 0.96, 95 % CI 0.46-2.01, p = 0.544).

CONCLUSION

Prophylactic CLND may be performed in PTMC patients with clinically uninvolved central lymph nodes but with high risk factors; multicenter studies with long-term follow-up are recommended to better understand the risk factors and surgical management for central nodes in PTMC.

Five Top Stories in Thyroid Pathology

CONTEXT

Thyroid carcinoma is the most common malignant tumor of endocrine organs, yet it only accounts for approximately 1% of all cancers in the United States with more than 35,000 new cases diagnosed each year and more than 450,000 people living with this disease. While most tumors can be diagnosed without much difficulty, a few tumor types, especially tumors with follicular pattern, sometimes pose a diagnostic challenge.

OBJECTIVE

To discuss morphologic, immunohistochemical, and molecular features of thyroid tumors. We also explore the clinicopathologic features of papillary microcarcinoma and medullary microcarcinoma and how the latter is related and differentiated from C-cell hyperplasia. Finally with the ever-growing list of organ systems involved in immunoglobulin (Ig) G4-related diseases, we discuss the still not completely explored IgG-4-related thyroid disease.

DATA SOURCES

Data were obtained from review of the pertinent peer-reviewed literature and institutional experience.

CONCLUSIONS

Histomorphologic evaluation still remains the gold standard for diagnosis in most cases of thyroid diseases. The application of ancillary studies such as immunohistochemistry and molecular diagnosis, including next-generation sequencing, is becoming more common.

Sonographic and Clinical Features of Papillary Thyroid Microcarcinoma Less than or Equal to Five Millimeters: A Retrospective Study

Objective

To retrospectively compare the sonographic and clinical features of papillary thyroid microcarcinoma (PTMC) ≤5 mm and PTMC >5 mm to improve the diagnostic value of ultrasonography.

Methods

A total of 367 cases of PTMC between January 2013 and December 2014 was included in this study. The patients were classified into group A (≤5 mm, n = 181) or group B (>5 mm, n = 186), and the sonographic and clinical features were reviewed and compared between the two groups.

Results

There was no significant difference in the shape, ratio of length/width, boundary, peripheral halo ring, echogenicity, cystic change and accompanying Hashimoto's thyroiditis between these two groups. However, the calcification (61.3% vs. 72.6%) and hypervascularity (13.8% vs. 24.7%) were more frequent in group B (p = 0.026 and 0.008, respectively). The patients were younger, and more patients were aged less than 45 years (41.4% vs. 57.0%) in group B. Capsular invasion (7.2% vs. 34.4%), multifocality (21.5% vs. 48.9%), bilaterality (17.1% vs. 39.8%), central lymph node metastasis (13.8% vs. 38.2%) and lateral lymph node metastasis (1.1% vs. 5.4%) were more frequent in group B. No clinical or sonographic feature was related to cervical lymph node metastasis in group A, while less than 45 years in age (p = 0.010), male gender (p = 0.040), capsular invasion (p<0.001), multifocality (p = 0.016) and calcification (p = 0.042) were related to cervical lymph node metastasis in group B.

Conclusions

The sonographic features of PTMC ≤5 mm were similar to those of PTMC >5 mm, including an irregular shape, a length/width ratio of ≥1, an unclear boundary, no peripheral halo ring, hypoechogenicity, no cystic change, calcification, no hypervascularity and no accompanying Hashimoto's thyroiditis. The clinical features of PTMC ≤5 mm were less aggressive than those of PTMC >5 mm.

Preliminary study of optical coherence tomography imaging to identify microscopic extrathyroidal extension in patients with papillary thyroid carcinoma

BACKGROUND AND OBJECTIVES

We evaluated the feasibility of using optical coherence tomography (OCT), to identify microscopic extrathyroidal extension (mETE) in ex vivo thyroidectomy specimens of patients who underwent thyroidectomy for the treatment of papillary thyroid carcinoma (PTC).

METHODS

A total of 170 ex vivo OCT images of the tumor, were acquired just after completion of thyroidectomy in 17 patients. The OCT images of each patient were separately evaluated by two blinded investigators, and the outcomes were compared with the histopathology reports.

RESULTS

The sensitivity and specificity of mETE identification from the OCT images were 81.4% and 86.0%, respectively, for the first investigator, and 82.9% and 87.0%, respectively, for the second investigator. Substantial agreement between the investigators was verified by Cohen's κ (Cohen's κ = 0.772).

CONCLUSION

In this preliminary study of a limited series of ex vivo thyroidectomy specimens, we verified the feasibility of OCT as a method of identifying mETE in patients with PTC.

Hashimoto's Thyroiditis Does Not Affect Ultrasonographical, Cytological, and Histopathological Features in Patients with Papillary Thyroid Carcinoma

The association between papillary thyroid carcinoma (PTC) and Hashimoto's thyroiditis (HT) is controversial. In this study, we aimed to compare preoperative thyroid functions, ultrasonography (US) features, fine-needle aspiration biopsy (FNAB) results, and histopathological characteristics of PTC in patients with and without HT. Data of 919 PTC patients were reviewed retrospectively. The diagnosis of HT was based on histopathological examination and patients were grouped as HT and non-HT. There were 1321 PTC lesions in 919 patients among which 317 (34.5 %) had coexistent HT. There were no significant differences in nodule volume, longitudinal diameter, texture, echogenicity, marginal regularity, presence of microcalcification and hypoechoic halo, and peripheral vascularization in patients with and without HT (p > 0.05, for all parameters). Macrocalcification was observed more frequently in the non-HT group (p = 0.021). FNAB results were similar in the two groups (p = 0.105). Distribution of variants, capsule invasion, vascular invasion, and extrathyroidal extension were observed with similar rates in the HT and non-HT groups. Lymph node metastasis was significantly higher in patients without HT (p = 0.012). Of the carcinomas, 66.1 % (n = 874) were papillary thyroid microcarcinoma (PTMC). Tumor size was lower in PTMC lesions coexistent with HT (p = 0.026). We observed lower rates of capsule invasion, extrathyroidal extension, and lymph node metastases in PTMC with HT compared to without HT (p = 0.007, p = 0.003, and p = 0.015, respectively). This study showed that US features, FNAB results, and histopathological findings of PTC lesions are not influenced by the presence of HT. However, PTMC seems to be related with less aggressive histopathological behavior in HT.

How sensitive (second-generation) thyroglobulin measurement is changing paradigms for monitoring patients with differentiated thyroid cancer, in the absence or presence of thyroglobulin autoantibodies

PURPOSE OF REVIEW

To discuss new insights regarding how sensitive (second-generation) thyroglobulin immunometric assays (TgIMAs), (functional sensitivities ≤0.10 μg/L) necessitate different approaches for postoperative thyroglobulin monitoring of patients with differentiated thyroid cancer (DTC), depending on the presence of thyroglobulin autoantibodies (TgAbs).

RECENT FINDINGS

Reliable low-range serum thyroglobulin measurement has both enhanced clinical utility and economic advantages, provided TgAb is absent (∼75% DTC patients). Basal [nonthyroid-stimulating hormone (TSH) stimulated] TgIMA measurement obviates the need for recombinant human TSH stimulation because basal TgIMA below 0.20 μg/L has comparable negative predictive value (>95%) to recombinant human TSH-stimulated thyroglobulin values below the cutoff of 2 μg/L. Now that radioiodine remnant ablation is no longer considered necessary to treat low-risk DTC, the trend and doubling time of low basal thyroglobulin values arising from postsurgical thyroid remnants have recognized prognostic significance. The major limitation of TgIMA testing is interference by TgAb (∼25% DTC patients), causing TgIMA underestimation that can mask disease. When TgAb is present, the trend in TgAb concentrations (measured by the same method) can serve as the primary (surrogate) tumor-marker and be augmented by thyroglobulin measured by a TgAb-resistant class of method (radioimmunoassay or liquid chromatography-tandem mass spectrometry).

SUMMARY

The growing use of TgIMA measurement is changing paradigms for postoperative DTC monitoring. When TgAb is absent, it is optimal to monitor the basal TgIMA trend and doubling time (using the same method) in preference to recombinant human TSH-stimulated thyroglobulin testing. When TgAb is present, interference renders TgIMA testing unreliable and the trend in serum TgAb concentrations per se (same method) can serve as a (surrogate) tumor-marker.

Ultrasonic features of papillary thyroid microcarcinoma and non-microcarcinoma

The present study analyzed the ultrasonic features of papillary thyroid microcarcinoma (PTMC) and papillary thyroid non-microcarcinoma (non-PTMC) with the aim of improving the diagnostic value of ultrasonography. The ultrasonic features of 328 patients with papillary thyroid carcinoma (PTC), as confirmed by pathology, were retrospectively analyzed. Patients were diagnosed with PTMC if the tumor size was ≤10 mm in diameter or non-PTMC if the tumor size was >10 mm in diameter. The shape, ratio of length/width, boundary, echo, peripheral halo ring, calcification, cystic changes, blood flow, lymph node metastasis and additional accompanying thyroid diseases were compared between the patients with PTMC and non-PTMC. In total, 389 nodules were identified in the 328 patients, including 209 PTMC nodules and 180 non-PTMC nodules. The multifocality rate was 15.9% (52/328). Ultrasound scans detected a total of 371 nodules, while 18 PMTC nodules were missed diagnosed and 57 nodules were misdiagnosed as benign nodules. Statistically significant differences in the boundary, ratio of length/width, cystic changes, blood flow and lymph node metastasis were observed between the PTMC and non-PTMC groups (P<0.05). However, no statistically significant differences were observed with regard to the shape, calcification, peripheral halo rings and additional accompanying thyroid diseases between the two groups (P>0.05). Therefore, ultrasound plays an important role in the diagnosis of PTC, with PTMC and non-PTMC exhibiting different ultrasonic performances.

Acoustic radiation force impulse imaging: a new tool for the diagnosis of papillary thyroid microcarcinoma

PURPOSE

To evaluate the diagnostic performance of ARFI imaging in differentiating between benign and malignant thyroid nodules <1 cm.

MATERIALS AND METHODS

173 pathologically proven thyroid nodules (77 benign, 96 malignant) in 157 patients were included in this study. Receiver-operating characteristic curve (ROC) analyses were performed to assess the diagnostic performance of conventional ultrasound (US) and ARFI imaging in papillary thyroid microcarcinoma (PTMC). The independent risk factors for predicting PTMC were evaluated.

RESULTS

The mean SWV value of benign and malignant thyroid nodules were 2.57 ± 0.79 m/s (range: 0.90-4.92 m/s) and 3.88 ± 2.24 m/s (range: 1.49-9.00 m/s) (P = 0.000). Az for VTI elastography score was higher than that for hypoechoic, absence of halo sign, and type III vascularity (P < 0.05). The optimal cut-offs for VTI elastography score and SWV were score 4 and 3.10 m/s. Gender, hypoechoic, taller than wide, VTI elastography score ≥ 4, and SWV > 3.10 m/s had been found to be independent risk factors for predicting PTMC.

CONCLUSION

ARFI elastography can provide elasticity information of PTMC quantitatively (VTQ) and directly reflects the overall elastic properties (VTI). Gender, hypoechogenicity, taller than wide, VTI elastography score ≥ 4, and SWV > 3.10 m/s are independent risk factors for predicting PTMC. ARFI elastography seems to be a new tool for the diagnosis of PTMC.