Multifocal Papillary Thyroid Cancer Increases the Risk of Central Lymph Node Metastasis

Papillary thyroid carcinoma: ≤ 10 mm does not always mean pN0. A multicentric real-world study

The incidence of papillary thyroid carcinoma (PTC) is increasing and PTC ≤ 10 mm (PTMC) accounts for most new diagnoses. PTMCs are not always low risk, as detection of lymph nodes metastasis (LNM) may occur. The purpose of the study was to analyze the clinical pattern, frequency, and independent risk factors of patients with PTMC and LNM. From January 2022 to June 2023, PTCs managed at CTO Hospital, Rome; Policlinico Vanvitelli, Naples; and Garibaldi Nesima Hospital, Catania were included. PTC management followed the same diagnostic-therapeutic procedures according to the ATA guidelines. Variables such as age, sex, maximum diameter, histologic evidence of LNM (HELNM +), Hashimoto's thyroiditis (HT), multifocality, capsule invasion, and histological subtype were considered. PTCs were divided according to HELNM and size. Two hundred ninety-eight PTCs were included. PTMCs were 136 (45.6%) and LNM occurred in 27.2% of them. In the HELNM + group, analysis of PTMC vs 'MacroPTC' (PTC > 10 mm) did not show any statistical difference. Multivariate regression revealed that young age (OR 0.93; CI 95% 0.90-0.96; p < 0.01) and male sex (male OR 3.44; CI 95% 1.16-10.20; p = 0.03) were the only independent risk factors for HELNM + in PTMC. The risk of LNM in PTMC is not negligible; therefore, a careful evaluation by an expert thyroidologist is mandatory for patients with small thyroid nodule, especially in younger and male patients before excluding surgery. In the future, new tools are needed to detect early PTMC with LNM before surgery.

Clinical prediction models for cervical lymph node metastasis of papillary thyroid carcinoma

PURPOSE

Accurate preoperative diagnosis of lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) remains an unsolved problem. This study aimed to construct a nomogram and scoring system for predicting LNM based on the clinical characteristics of patients with PTC.

METHODS

1400 patients with PTC who underwent thyroidectomy and lymph node dissection at the First Affiliated Hospital of Sun Yat-sen University were retrospectively enrolled and randomly divided into training and internal testing sets. Furthermore, 692 patients with PTC from three other medical centers were collected as external testing sets. Least absolute shrinkage and selection operator (LASSO) was used to screen the predictors, and a nomogram was constructed. In addition, a scoring system was constructed using 10-fold cross-validation. The performances of the two models were verified among datasets and compared with preoperative ultrasound (US).

RESULTS

Six independent predictors were included in the multivariate logistic model: age, sex, US diagnosis of LNM, tumor diameter, location, and thyroid peroxidase antibody level. The areas under the receiver operating characteristic curve (AUROC) (95% confidence interval) of this nomogram in the training, internal testing, and three external testing sets were 0.816 (0.791-0.840), 0.782 (0.727-0.837), 0.759 (0.699-0.819), 0.749 (0.667-0.831), and 0.777 (0.726-0.828), respectively. The AUROC of the scoring system were 0.810 (0.785-0.835), 0.772 (0.718-0.826), 0.736 (0.675-0.798), 0.717 (0.635-0.799) and 0.756 (0.704-0.808), respectively. The prediction performances were both significantly superior to those of preoperative US (P < 0.001).

CONCLUSION

The nomogram and scoring system performed well in different datasets and significantly improved the preoperative prediction of LNM than US alone.

Cytosolic Cadherin 4 promotes angiogenesis and metastasis in papillary thyroid cancer by suppressing the ubiquitination/degradation of β-catenin

BACKGROUND

Although the long-term prognosis of papillary thyroid cancer (PTC) is favorable, distant metastasis significantly compromises the prognosis and quality of life for patients with PTC. The Cadherin family plays a pivotal role in tumor metastasis; however, the involvement of Cadherin 4 (CDH4) in the metastatic cascade remains elusive.

METHODS

The expression and subcellular localization of CDH4 were determined through immunohistochemistry, immunofluorescence, and western blot analyses. The impact of CDH4 on cell migration, invasion, angiogenesis, and metastasis was assessed using transwell assays, tube formation assays, and animal experiments. Immunoprecipitation assay and mass spectrometry were employed to examine protein associations. The influence of CDH4 on the subcellular expression of β-catenin and active β-catenin was investigated via western blotting and immunofluorescence. Protein stability and ubiquitination assay were employed to verify the impact of CDH4 on β-catenin degradation. Rescue experiments were performed to ensure the significance of CDH4 in regulating nuclear β-catenin signaling.

RESULTS

CDH4 was found to be significantly overexpressed in PTC tissues and predominantly localized in the cytoplasm. Furthermore, the overexpression of CDH4 in tumor tissues is associated with lymph node metastasis in PTC patients. Cytosolic CDH4 promoted the migration, invasion, and lung metastasis of PTC cells and stimulated the angiogenesis and tumorigenesis of PTC; however, this effect could be reversed by Tegavivint, an antagonist of β-catenin. Mechanistically, cytosolic CDH4 disrupted the interaction between β-catenin and β-TrCP1, consequently impeding the ubiquitination process of β-catenin and activating the nuclear β-catenin signaling.

CONCLUSIONS

CDH4 induces PTC angiogenesis and metastasis via the inhibition of β-TrCP1-dependent ubiquitination of β-Catenin.

The Impact of Total Tumor Diameter on Lymph Node Metastasis and Tumor Recurrence in Papillary Thyroid Carcinomas

(1) Introduction: The impact of multifocality/bilaterality on the prognosis of papillary thyroid carcinoma (PTC) is a matter of debate. In order to clarify this debate, several studies have attempted to identify additional parameters associated with poor prognosis, including total tumor diameter (TTD), in the context of multifocal PTCs. In this context, this study was carried out to investigate the impact of TTD on tumor recurrence and lymph node metastasis (LNM) in PTCs. (2) Materials and Methods: The sample of this single-center retrospective study consisted of 706 patients diagnosed with PTC. TTD was calculated as the sum of the largest diameters of tumor foci in multifocal tumors. The resulting TTDs were grouped into TTDs ≤ 10 mm, TTDs > 10 mm, TTDs ≤ 20 mm, and TTDs > 20 mm, using 10 mm and 20 mm as cutoff values. (3) Results: There was no significant difference between multifocal papillary microcarcinomas (PTMCs) with a TTD of >10 mm and unifocal PTCs with a primary tumor diameter (PTD) of >10 mm except for advanced age and lymphovascular invasion (LVI). In addition, perineural invasion (PNI) and TTD > 10 mm were found to be significant risk factors for LNM, and PNI, TTD > 10 mm, TTD > 20 mm, and bilaterality were found to be significant risk factors for recurrence. LVI, and TTD > 10 mm were found to be independent significant predictors for recurrence, and LVI and extrathyroidal extension (ETE) were found to be independent significant predictors for LNM. (4) Conclusions: Considering TTD > 10 mm in recurrence risk categorization models and adopting a clinical approach that takes into account multifocal PTMCs with TTD > 10 mm along with unifocal PTCs with PTD > 10 mm may be more useful in terms of clinical management of the disease.

A nomogram based on multimodal ultrasound and clinical features for the prediction of central lymph node metastasis in unifocal papillary thyroid carcinoma

OBJECTIVES

To build a predictive model for central lymph node metastasis (CLNM) in unifocal papillary thyroid carcinoma (UPTC) using a combination of clinical features and multimodal ultrasound (MUS).

METHODS

This retrospective study, included 390 UPTC patients who underwent MUS between January 2017 and October 2022 and were divided into a training cohort (n = 300) and a validation cohort (n = 90) based on a cut-off date of June 2022. Independent indicators for constructing the predictive nomogram models were identified using multivariate regression analysis. The diagnostic yield of the 3 predictive models was also assessed using the area under the receiver operating characteristic curve (AUC).

RESULTS

Both clinical factors (age, diameter) and MUS findings (microcalcification, virtual touch imaging score, maximal value of virtual touch tissue imaging and quantification) were significantly associated with the presence of CLNM in the training cohort (all P < .05). A predictive model (MUS + Clin), incorporating both clinical and MUS characteristics, demonstrated favourable diagnostic accuracy in both the training cohort (AUC = 0.80) and the validation cohort (AUC = 0.77). The MUS + Clin model exhibited superior predictive performance in terms of AUCs over the other models (training cohort 0.80 vs 0.72, validation cohort 0.77 vs 0.65, P < .01). In the validation cohort, the MUS + Clin model exhibited higher sensitivity compared to the CLNM model for ultrasound diagnosis (81.2% vs 21.6%, P < .001), while maintaining comparable specificity to the Clin model alone (62.3% vs 47.2%, P = .06). The MUS + Clin model demonstrated good calibration and clinical utility across both cohorts.

CONCLUSION

Our nomogram combining non-invasive features, including MUS and clinical characteristics, could be a reliable preoperative tool to predict CLNM treatment of UPTC.

ADVANCES IN KNOWLEDGE

Our study established a nomogram based on MUS and clinical features for predicting CLNM in UPTC, facilitating informed preoperative clinical management and diagnosis.

Is unicentric familial papillary thyroid microcarcinoma different from multicentric?

BACKGROUND

Familial papillary thyroid microcarcinoma (FPTMC) appears to be more aggressive than sporadic papillary thyroid microcarcinoma (SPTMC). However, there are authors who indicate that unicentric FPTMC has a similar prognosis to SPTMC. The objective is to analyze whether unicentric FPTMC has a better prognosis than multicentric FPTMC.

DESIGN AND METHODS

Type of study: National multicenter longitudinal analytical observational study.

STUDY POPULATION

Patients with FPTMC.

STUDY GROUPS

Two groups were compared: Group A (unicentric FPTMC) vs. Group B (multicentric FPTMC).

STUDY VARIABLES

It is analyzed whether between the groups there are: a) differentiating characteristics; and b) prognostic differences.

STATISTICAL ANALYSIS

Cox regression analysis and survival analysis.

RESULTS

Ninety-four patients were included, 44% (n = 41) with unicentric FPTMC and 56% (n = 53) with multicentric FPTMC. No differences were observed between the groups according to socio-familial, clinical or histological variables. In the group B a more aggressive treatment was performed, with higher frequency of total thyroidectomy (99 vs. 78%; p = 0.003), lymph node dissection (41 vs. 15%; p = 0.005) and therapy with radioactive iodine (96 vs. 73%; p = 0.002). Tumor stage was similar in both groups (p = 0.237), with a higher number of T3 cases in the group B (24 vs. 5%; p = 0.009). After a mean follow-up of 90 ± 68.95 months, the oncological results were similar, with a similar disease persistence rate (9 vs. 5%; p = 0.337), disease recurrence rate (21 vs. 8%; p = 0.159) and disease-free survival (p = 0.075).

CONCLUSIONS

Unicentric FPTMC should not be considered as a SPTMC due to its prognosis is similar to multicentric FPTMC.

Risk prediction of second primary malignant tumor in primary differentiated thyroid cancer patients: a population-based study

PURPOSE

To investigate the risk factors of second primary malignant tumor (SPMT) in patients with differentiated thyroid cancer (DTC) and establish a competing risk nomogram to predict the probability of SPMT occurrence.

METHODS

We retrieved data from the Surveillance, Epidemiology, and End Results (SEER) database for patients diagnosed with DTC between 2000 and 2019. The Fine and Gray subdistribution hazard model was employed to identify SPMT risk factors in the training set and develop a competing risk nomogram. Model evaluation was performed using area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA).

RESULTS

A total of 112,257 eligible patients were included in the study and randomized into a training set (n = 112,256) and a validation set (n = 33,678). The cumulative incidence rate of SPMT was 15% (n = 9528). Age, sex, race, tumor multifocality, and TNM stage were independent risk factors of SPMT. The calibration plots showed good agreement between the predicted and observed SPMT risks. The 10-year AUCs of the calibration plots were 70.2 (68.7-71.6) in the training set and 70.2 (68.7-71.5) in the validation set. Moreover, DCA showed that our proposed model resulted in higher net benefits within a defined range of risk thresholds. The cumulative incidence rate of SPMT differed among risk groups, classified according to nomogram risk scores.

CONCLUSION

The competing risk nomogram developed in this study exhibits high performance in predicting the occurrence of SPMT in patients with DTC. These findings may help clinicians identify patients at distinct levels of risk of SPMT and develop corresponding clinical management strategies.

Bilaterality, not multifocality, is an independent risk factor for recurrence in low-risk papillary thyroid cancer

BACKGROUND

The impact of multifocality and bilaterality on recurrence in patients with low-risk papillary thyroid cancer (PTC) is relevant when considering patients for a de-escalated treatment strategy: hemithyroidectomy instead of total thyroidectomy followed with or without radioactive iodine. This study aims to analyze contralateral tumor probability in patients treated for low-risk PTC and assess multifocality and bilaterality as possible predictors for recurrence.

METHODS

Patients with low-risk PTC treated with total thyroidectomy followed with or without radioactive iodine in the Netherlands between 2005 and 2015 were included in this study. Patients were identified from the Netherlands Comprehensive Cancer Organization (IKNL) and linked with the nationwide network and registry of Pathology in the Netherlands (PALGA). Contralateral tumor probability and recurrence were assessed.

RESULTS

Of 791 included patients, 41.8% (331 of 791) had multifocal disease, with 68.9% (228 of 331) of those patients having bilateral disease. The contralateral tumor probability after hemithyroidectomy was 24.6% (150 of 610) for patients with unifocal disease and 43.1% (78 of 181) for patients with multifocal disease. We found a higher trend of recurrence in patients with bilateral disease, regardless of multifocality: in patients with contralateral disease after precompletion diagnosed unifocal disease 7.3% (11 of 150) had recurrent disease, and patients without contralateral disease after precompletion diagnosed multifocal disease 1.9% (2 per 103) had recurrence. Cox regression analysis showed that bilaterality (hazard ratio = 3.621, 95% confidence interval = 1.548 to 8.471) was the sole statistically significant risk factor for recurrence.

CONCLUSION

Low recurrence rates are found in patients with either multifocal or bilateral disease with low-risk PTC. Bilaterality should be taken into account when considering these patients for de-escalated treatment strategy.

The value of total tumor diameter in unilateral multifocal papillary thyroid carcinoma: a propensity score matching analysis

Background

Tumor multifocality is frequently observed in papillary thyroid carcinoma (PTC). However, the maximum tumor diameter (MTD), currently utilized in various staging schemes, might not accurately indicate the level of aggressiveness exhibited by multifocal tumors. We aimed to investigate the relationship between total tumor diameter (TTD) and clinicopathological features of papillary thyroid carcinoma.

Methods

Retrospective data analysis was done on 1936 individuals who underwent complete thyroidectomy for PTC. Patients were classified into subgroups according to unilateral multifocality, central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM). The relationships of clinicopathological features among these groups were analyzed.

Results

Unilateral multifocality was observed in 117 patients. The clinicopathological features of the unilateral multifocal PTC were similar to the unifocal PTC with approximate TTD. The unilateral multifocality played no independent role in CLNM and LLNM. Moreover, the efficiency of TTD in predicting CLNM and LLNM was significantly higher than that of MTD.

Conclusion

In the case of unilateral multifocal PTC, TTD is a more accurate indicator of the biological characteristics of the tumor than MTD.

Development and validation of a dynamic nomogram based on conventional ultrasound and contrast-enhanced ultrasound for stratifying the risk of central lymph node metastasis in papillary thyroid carcinoma preoperatively

Purpose

The aim of this study was to develop and validate a dynamic nomogram by combining conventional ultrasound (US) and contrast-enhanced US (CEUS) to preoperatively evaluate the probability of central lymph node metastases (CLNMs) for patients with papillary thyroid carcinoma (PTC).

Methods

A total of 216 patients with PTC confirmed pathologically were included in this retrospective and prospective study, and they were divided into the training and validation cohorts, respectively. Each cohort was divided into the CLNM (+) and CLNM (-) groups. The least absolute shrinkage and selection operator (LASSO) regression method was applied to select the most useful predictive features for CLNM in the training cohort, and these features were incorporated into a multivariate logistic regression analysis to develop the nomogram. The nomogram's discrimination, calibration, and clinical usefulness were assessed in the training and validation cohorts.

Results

In the training and validation cohorts, the dynamic nomogram (https://clnmpredictionmodel.shinyapps.io/PTCCLNM/) had an area under the receiver operator characteristic curve (AUC) of 0.844 (95% CI, 0.755-0.905) and 0.827 (95% CI, 0.747-0.906), respectively. The Hosmer-Lemeshow test and calibration curve showed that the nomogram had good calibration (p = 0.385, p = 0.285). Decision curve analysis (DCA) showed that the nomogram has more predictive value of CLNM than US or CEUS features alone in a wide range of high-risk threshold. A Nomo-score of 0.428 as the cutoff value had a good performance to stratify high-risk and low-risk groups.

Conclusion

A dynamic nomogram combining US and CEUS features can be applied to risk stratification of CLNM in patients with PTC in clinical practice.

Nomogram prediction for cervical lymph node metastasis in multifocal papillary thyroid microcarcinoma

Aim

Accurate preoperative prediction of cervical lymph node metastasis (LNM) in patients with mPTMC provides a basis for surgical decision making and the extent of tumor resection. This study aimed to develop and validate an ultrasound radiomics nomogram for the preoperative assessment of LN status.

Methods

A total of 450 patients pathologically diagnosed with mPTMC were enrolled, including 348 patients in the modeling group and 102 patients in the validation group. Univariate and multivariate logistic regression analyses were performed on the basic information, ultrasound characteristics, and American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) scores of the patients in the modeling group to identify independent risk factors for LNM in mPTMC and to construct a logistic regression equation and nomogram to predict the risk of LNM. The validation group data were used to evaluate the predictive performance of the nomogram.

Results

Male sex, age <40 years, a single lesion with a maximum diameter >0.5 cm, capsular invasion, a maximum ACR score >9 points, and a total ACR score >19 points were independent risk factors for the development of cervical LNM in mPTMC. Both the area under the curve (AUC) and concordance index (C-index) of the prediction model constructed from the above six factors were 0.838. The calibration curve of the nomogram was close to the ideal diagonal line. Furthermore, decision curve analysis (DCA) demonstrated a significantly greater net benefit of the model. The external validation demonstrated the reliability of the prediction nomogram.

Conclusions

The presented radiomics nomogram, which is based on ACR TI-RADS scores, shows favorable predictive value for the preoperative assessment of LNs in patients with mPTMC. These findings may provide a basis for surgical decision making and the extent of tumor resection.

Clinicopathological features and prognostic factors analysis of multiple synchronous distinct subtypes of primary thyroid carcinoma

PURPOSE

To investigate the clinicopathological features, diagnosis, treatment, and prognosis of multiple synchronous distinct subtypes of primary thyroid carcinomas.

METHODS

The clinical data of 68 cases of synchronous carcinomas of the thyroid (STC) admitted to the Department of Thyroid Surgery in our hospital from January 2013 to December 2021 were reviewed. According to the pathological type, they were divided into the Synchronous differentiated and differentiated thyroid Carcinoma (SDDTC) group (42 cases), the Synchronous medullary and differentiated thyroid Carcinoma (SMDTC) group (18 cases), and the Synchronous Anaplastic and differentiated thyroid Carcinoma (SADTC)group (8 cases). The diagnosis, treatment, and survival of patients in each group were analyzed.

RESULTS

Women with coexisting thyroid cancer were predominant (59 cases). Most of the symptoms were found on physical examination (47.1%) and neck mass (45.6%). The median age of patients in the SDDTC group, SADTC group, and SMDTC group was 47.5 (28-74) years old, 68.5 (26-75) years old, and 56.5 (39-74) years old. The age of the SADTC group and SMDTC group was older than that of the SDDTC group (P = 0.04, P = 0.03), and the rate of lymph node metastasis in groups SADTC (62.5%) and SMDTC (55.6%) was higher than in group SDDTC (21.4%). The disease course time, tumor location, clinical stage, and mortality of the SADTC group were significantly different from those of the SDDTC group and SMDTC group (P < 0.05). The overall survival of patients with synchronous carcinomas of the thyroid was 6-105 months, and the median overall survival was 38.5 months. The tumor-free survival was 0-90 months, 19.1% of patients developed distant metastasis, 11.8% of patients had postoperative recurrence, as well as the survival rate was estimated 91.18%. Cox model multivariate analysis showed that cervical lateral lymph node metastasis and tumor stage III/IV were independent risk factors for progression-free survival(PFS). The comparison results of the survival curves showed that the overall survival (OS)of the patients in the SADTC group was significantly worse (P < 0.01), while there was no significant difference in the PFS of different pathological types (χ2 = 5.024, P = 0.081).The OS of different treatment methods was significantly different (P = 0.002), but there was no significant difference in OS between local recurrence and distant metastases with or without surgery (χ2 = 0.954, P = 0.329).

CONCLUSIONS

The STC has relatively unique clinical characteristics, and most patients can get a better prognosis after radical surgery. Pathological type, lateral cervical lymph node metastasis, tumor stage, and treatment are important factors which affect the prognosis of the disease. Since there are two distinct tumors with different aggressiveness, treatment options, and prognosis, individualized management is required.

Lobo-isthmectomy in the management of differentiated thyroid cancer

We have recently witnessed a rapid increase in the incidence of differentiated thyroid carcinoma (DTC), particularly low and very low-risk papillary thyroid carcinoma. Simultaneously, the number of cancer-related deaths has remained stable for more than 30 years. Such an indolent nature and long-term survival prompted researchers and experts to an ongoing discussion on the adequacy of DTC management to avoid, on the one hand, the overtreatment of low-risk cases and, on the other hand, the undertreatment of highly aggressive ones.The most recent guidelines of the American Thyroid Association (ATA GL) moved primary thyroid surgery in DTC towards a less aggressive approach by making lobectomy an option for patients with intrathyroidal low-risk DTC tumors up to 4 cm in diameter without evidence of extrathyroidal extension or lymph node metastases. It was one of the key changes in DTC management proposed by the ATA in 2015.Following the introduction of the 2015 ATA GL, the role of thyroid lobectomy in DTC management has slowly become increasingly important. The data coming from analyses of the large databases and retrospective studies prove that a less extensive surgical approach, even if in some reports it was related to a slight increase of the risk of recurrence, did not show a negative impact on disease-specific and overall survival in T1T2N0M0 low-risk DTC. There is no doubt that making thyroid lobectomy an option for low-risk papillary and follicular carcinomas was an essential step toward the de-escalation of treatment in thyroid carcinoma.This review summarizes the current recommendations and evidence-based data supporting the necessity of de-escalation of primary thyroid surgery in low-risk DTC. It also discusses the controversies raised by introducing new ATA guidelines and tries to resolve some open questions.

Models of ultrasonic radiomics and clinical characters for lymph node metastasis assessment in thyroid cancer: a retrospective study

Background

Preoperative prediction of cervical lymph node metastasis in papillary thyroid carcinoma provided a basis for tumor staging and treatment decision. This study aimed to investigate the utility of machine learning and develop different models to preoperatively predict cervical lymph node metastasis based on ultrasonic radiomic features and clinical characteristics in papillary thyroid carcinoma nodules.

Methods

Data from 400 papillary thyroid carcinoma nodules were included and divided into training and validation group. With the help of machine learning, clinical characteristics and ultrasonic radiomic features were extracted and selected using randomforest and least absolute shrinkage and selection operator regression before classified by five classifiers. Finally, 10 models were built and their area under the receiver operating characteristic curve, accuracy, sensitivity, specificity, positive predictive value and negative predictive value were measured.

Results

Among the 10 models, RF-RF model revealed the highest area under curve (0.812) and accuracy (0.7542) in validation group. The top 10 variables of it included age, seven textural features, one shape feature and one first-order feature, in which eight were high-dimensional features.

Conclusions

RF-RF model showed the best predictive performance for cervical lymph node metastasis. And the importance features selected by it highlighted the unique role of higher-dimensional statistical methods for radiomics analysis.

Dual-modal radiomics for predicting cervical lymph node metastasis in papillary thyroid carcinoma

BACKGROUND

Preoperative prediction of cervical lymph node metastasis (CLNM) in patients with papillary thyroid carcinoma (PTC) is significant for surgical decision-making.

OBJECTIVE

This study aims to develop a dual-modal radiomics (DMR) model based on grayscale ultrasound (GSUS) and dual-energy computed tomography (DECT) for non-invasive CLNM in PTC.

METHODS

In this study, 348 patients with pathologically confirmed PTC at Jiangsu University Affiliated People's Hospital who completed preoperative ultrasound (US) and DECT examinations were enrolled and randomly assigned to training (n = 261) and test (n = 87) cohorts. The enrolled patients were divided into two groups based on pathology findings namely, CLNM (n = 179) and CLNM-Free (n = 169). Radiomics features were extracted from GSUS images (464 features) and DECT images (960 features), respectively. Pearson correlation coefficient (PCC) and the least absolute shrinkage and selection operator (LASSO) regression with 10-fold cross-validation were then used to select CLNM-related features. Based on the selected features, GSUS, DECT, and GSUS combined DECT radiomics models were constructed by using a Support Vector Machine (SVM) classifier.

RESULTS

Three predictive models based on GSUS, DECT, and a combination of GSUS and DECT, yielded performance of areas under the curve (AUC) = 0.700 [95% confidence interval (CI), 0.662-0.706], 0.721 [95% CI, 0.683-0.727], and 0.760 [95% CI, 0.728-0.762] in the training dataset, and AUC = 0.643 [95% CI, 0.582-0.734], 0.680 [95% CI, 0.623-0.772], and 0.744 [95% CI, 0.686-0.784] in the test dataset, respectively. It shows that the predictive model combined GSUS and DECT outperforms both models using GSUS and DECT only.

CONCLUSIONS

The newly developed combined radiomics model could more accurately predict CLNM in PTC patients and aid in better surgical planning.

[Hemithyroidectomy or total thyroidectomy for low-risk papillary thyroid cancer? : Surgical criteria for primary and secondary choice of treatment in an interdisciplinary treatment concept]

The increase in small intrathyroid papillary thyroid cancer (PTC) observed worldwide over the past two decades, with no increase in cancer-specific mortality, has challenged the previous concept of total thyroidectomy as a one-size-fits-all panacea. After exclusion of papillary microcarcinomas, a systematic review of 20 clinical studies published since 2002, which compared hemithyroidectomy (HT) to total thyroidectomy (TT), found comparable long-term oncological outcomes for low-risk papillary thyroid cancer (LRPTC) 1-4 cm in diameter, whereas postoperative complication rates were markedly lower for HT. To refine individual treatment plans, HT should be combined with ipsilateral central lymph node dissection and intraoperative frozen section analysis for staging. Based on recent evidence from studies and in consideration of individual risk factors, patients with LRPTC can be offered the concept of HT as an alternative to the standard TT. A prerequisite for the treatment selection and decision is a comprehensive patient clarification of the possible advantages and disadvantages of both approaches.

Risk factors of cervical lymph node metastasis in multifocal papillary thyroid cancer

Introduction

Identifying risk variables for cervical lymph node metastases in multifocality papillary thyroid cancer (MPTC) could assist surgeons in determining whether cervical lymph node dissection would be an appropriate surgical option.

Methods

A retrospective cohort of 2006 patients with papillary thyroid cancer were selected. MPTC (N = 460) was defined as the presence of two or more foci of PTC. The risk factors for central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) in MPTC were investigated by univariate and multivariate analyses, including the following items: age at diagnosis, gender, Hashimoto's thyroiditis, extrathyroidal extension (ETE), maximal axial diameter (MAD) and the sum of axial diameters (SAD) of tumor. In addition, CLNM was used to evaluate LLNM.

Results

The incidence of CLNM and LLNM was 44.57% and 17.17%, respectively. The multivariate analysis demonstrated that gender, extrathyroidal extension (ETE), age, maximal axial diameter (MAD), and the sum of axial diameters (SAD) were related to increased risk for CLNM in MPTC (p < 0.05). The area under the receiver operating characteristic (ROC) curve (AUC) for age at diagnosis of CLNM was 0.647, the cut-off value was 50 years old. Additionally, by multivariate analysis, CLNM, ETE, MAD, and SAD were independent risk factors for LLNM in MPTC (p < 0.05). ROC curve analysis demonstrates that AUC for MAD and SAD diagnosis of LLNM were 0.639 and 0.757, and the cut-off values were 16 and 26 mm, respectively.

Conclusions

MPTC patients who have risk factors for CLNM were advised to perform prophylactic central lymph node dissection (CLND). Additionally, the presence of risk factors for LLNM should be individually evaluated and analyzed for the necessity of lateral lymph node dissection.

Quantitative analysis of contrast-enhanced ultrasound combined with ultrasound in the unifocal papillary thyroid micro-carcinoma

OBJECTIVE

To evaluate diagnostic value of ultrasound (US) combined with contrast-enhanced ultrasound (CEUS) in the invasiveness of unifocal papillary thyroid micro-carcinoma (UPTMC) without capsule-invasion.

METHODS

This retrospective study included data from patients with UPTMC who received US and CEUS examinations in the Ultrasound Department of the Central Hospital of Changsha, China between June 2019 and September 2021. Univariate and multivariate logistic regression analysis were used to evaluate the risk of US and CEUS parameters for UPTMC. Diagnostic performance was estimated by ROC analysis.

RESULTS

A total of 136 cases were enrolled, including invasive UPTMC (n = 47) and non-invasive UPTMC (n = 89), which were divided into test set (n = 109) and validation set (n = 27). The occurrence of microcalcification and the ratios (R) of each time-intensity curve (TIC) of CEUS parameter were significantly higher in patients with invasive UTPMC than non-invasive UPTMC (all P < 0.05). Additionally, nodular diameter was significantly longer in the invasive group (P < 0.05). Multivariate analysis showed that microcalcification (OR = 2.917, 95% CI: 1.002-8.491, P = 0.050), R-TTP > 1 (OR = 3.376, 95%CI: 1.267-8.994, P = 0.015), R-DS > 1 (OR = 6.558, 95% CI: 2.358-18.243, P < 0.010) were independently associated with invasive UPTMC. The sensitivities of US, CEUS and their combined application were 82.1%, 46.2% and 79.5%, respectively, and their specificities were 37.1%, 88.6% and 61.4%, respectively. The combination of the two methods had the best diagnostic efficiency (AUC=0.775)compared to US (AUC = 0.596) and CEUS (AUC = 0.750).

CONCLUSION

The combination of US and CEUS might have good diagnostic value for UPTMC with capsule non-invasion.

Long-term follow-up ultrasonography surveillance in a large cohort of patients with papillary thyroid carcinoma

OBJECTIVE

This study aimed to investigate the predictive factors as well as the time and age course of recurrence/persistence in a large cohort of postoperative patients with papillary thyroid carcinoma (PTC) based on the long-term ultrasonography (US) follow-up data.

METHODS

Between January 2007 and December 2016, 3106 patients underwent surgery for PTC and at least two postoperative US follow-up examination over more than three years. Tumor recurrence/persistence was confirmed based on the follow-up US data and histopathological results. Univariate and multivariate analyses were performed to evaluate the predictive factors of tumor recurrence/persistence. Kaplan-Meier survival analysis was used to evaluate the recurrence-/persistence-free survival curve based on the US results.

RESULTS

A total of 321(10.3%) patients developed tumor recurrence/persistence during 54.3 months of mean follow-up (range 36-135 months), including 268(83.5%) cases of lymph node recurrence/persistence, 37 (11.5%) cases of non-lymph node recurrence/persistence, and 16(5%) cases of both types. Recurrence/persistence was observed using US examination at a mean interval of 23.6 ± 21.6 months (range 1-135 months) after surgery and peak incidence was observed 1-2 years after initial treatment. Younger (20-30 years old) and older (70-80 years old) patients had a higher proportion of tumor recurrence/persistence. Multifocality, advanced T and advanced N stages were independent risk factors of tumor recurrence/persistence.

CONCLUSION

Tumor recurrence/persistence of PTC usually occurs during the early postoperative period. For patients with multifocal cancer, advanced T and N stage, the US surveillance examination should be cautiously performed, especially in younger and older patients.

Quantification and Pattern of Central Compartment Lymph Nodes in pN1a Papillary Thyroid Cancer Patients

Background: The background is to investigate the results of central compartment lymphadenectomy for pN1a papillary thyroid carcinoma (PTC) with regard to quantification and pattern of resected lymph nodes thereby providing basis for future compartment VI surgical intervention. Methods: The study comprised 443 pN1a PTC patients whose clinicopathological characteristics and central compartment lymphadenectomy results were compared and correlated with the primary thyroid cancer and lymph node metastasis (LNM) features. Ultimately, multivariate analysis was conducted to identify statistically significant impact factors for a high metastatic ratio (MR). Results: Dissected lymph nodes (DLNs) were more frequently identified in right level VI than left (P < .05) although there was no difference in in the number of resected metastatic lymph nodes (MLNs). Male sex, multifocality, extrathyroidal extension (ETE), and fewer DLNs were related to a high MR. There was a positive correlation between DLN and MLN, and a negative correlation between DLN and MR. Disease multifocality and ETE were identified more frequently in the left than the right thyroid lobe. Conclusion: The outcome of central compartment lymphadenectomy in pN1a PTC patients is associated with several factors, and a thorough dissection of lymph nodes improves the rate of metastatic lymph node resection.

Correlation Analysis of Nodular Sonographic Parameters with Cervical Lymph Node Metastases in Papillary Thyroid Carcinoma

Background

Papillary thyroid carcinoma (PTC) is the most common thyroid carcinoma and is prone to cervical lymph node metastases (CLNM). We aim to analyze the correlation between clinical information, ultrasonic parameters of PTC, and CLNM.

Methods

1335 patients who had pathologically confirmed unifocal PTC were enrolled in this retrospective cohort study. Univariate and multivariate logistic analyses were performed to predict CLNM in PTC patients. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance.

Results

Univariate analysis showed that gender, age, maximum tumor diameter and volume, and cross-sectional and longitudinal aspect ratio were related to CLNM (P < 0.05). Multivariate logistic analysis showed that gender, age, maximum tumor diameter, and volume were independent correlative factors, and the cross-sectional aspect ratio had significant difference for PTC2 to predict CLNM. The area under the curve (AUC) of the maximum tumor diameter and volume was 0.738 and 0.733, respectively. Maximum tumor diameter and volume and the cross-sectional and longitudinal aspect ratio were statistically significant following analysis of variance (P < 0.05).

Conclusions

Younger age, male, and larger tumor were high risk factors for CLNM in patients with unifocal PTC. The cross-sectional aspect ratio had a more effective predictive value for CLNM in patients with larger thyroid tumors.

Validation of Ultrasound Risk Stratification Systems for Cervical Lymph Node Metastasis in Patients with Thyroid Cancer

Simple Summary

Ultrasound (US) malignancy risk stratification systems (RSS) for cervical lymph nodes (LNs) have not been fully established in patients with thyroid cancer. In this study, we assessed the malignancy risks of each US feature and risk category from the Korean Society of Thyroid Radiology (KSThR) and the European Thyroid Association (ETA). Both systems effectively classified malignancy risks; however, 15.1% of LNs were unclassifiable in ETA RSS. Suspicious US features of hyperechogenicity, cystic change, echogenic foci, and abnormal vascularity were independently associated with metastasis. When the primary tumor characteristics were assessed, tumor multiplicity was associated with metastasis in the indeterminate LN group. We refined this system and proposed an RSS based on the KSThR system for cervical LNs in patients with thyroid cancer.

Abstract

A malignancy risk stratification system (RSS) for cervical lymph nodes (LNs) has not been fully established. This study aimed to validate the current RSS for the diagnosis of cervical LN metastasis in thyroid cancer. In total, 346 LNs from 282 consecutive patients between December 2006 and June 2015 were included. We determined the malignancy risk of each ultrasound (US) feature and performed univariable and multivariable logistic regression analyses. Each risk category from the Korean Society of Thyroid Radiology (KSThR) and the European Thyroid Association (ETA) was applied to calculate malignancy risks. The effects of size, number of suspicious features, and primary tumor characteristics were analyzed to refine the current RSS. Suspicious features including echogenic foci, cystic change, hyperechogenicity, and abnormal vascularity were independently predictive of malignancy (p ≤ 0.045). The malignancy risks of probably benign, indeterminate, and suspicious categories were 2.2–2.5%, 26.8–29.0%, and 85.8–87.4%, respectively, according to the KSThR and ETA criteria. According to the ETA criteria, 15.1% of LNs were unclassifiable. In indeterminate LNs, multiplicity of the primary tumor was significantly associated with malignancy (odds ratio, 6.53; p = 0.004). We refined the KSThR system and proposed a US RSS for LNs in patients with thyroid cancer.

Clinicopathological and ultrasound features as risk stratification predictors of clinical and pathological nodal status in papillary thyroid carcinoma: a study of 748 patients

Background

Papillary thyroid carcinoma (PTC) is the most common histological type of thyroid malignancy that tends to metastasize to cervical lymph nodes. In the present study, we aimed to investigate which clinicopathologic and ultrasound features of PTC are associated with clinical lymph node metastasis (LNM) and numbers of pathological LNM.

Methods

From January 2016 to December 2018, we identified a cohort of patients with PTC who underwent cervical ultrasonography and were diagnosed through operation and pathology. Clinical N1(cN1) and > 5 pathologic N1(pN1) were considered in the postoperative stratification to have an intermediate risk according to the 2015 ATA guidelines. Clinicopathological and ultrasound features in PTC patients were performed in accordance with the independent risk factors of cN1 and > 5pN1 respectively by using the univariate and multivariate analyses.

Results

We collected 748 PTC patients in the final inclusion criteria. There were 688 cN0 cases and 60 cN1 cases. From the analyses, primary tumor size > 2 cm, capsule contact, extrathyroidal extensions (ETE) and central LNM remained independent risk factors for cN1 in PTC patients. In the 748 PTC patients, 707 cases had ≤ 5 pN1, and 41 cases had > 5 pN1. Multifocality, primary tumor size > 2 cm, capsule contact and ETE are significant independent risk factors for > 5 pN1.

Conclusions

We concluded that multifocality, primary tumor size > 2 cm, capsule contact, ETE and central LNM were independent risk factors for the intermediate risk stratification in patients with PTC. Ultrasonography is a good technique for the preoperative lymph node staging of PTC and is helpful for detecting LNM.

Nomograms based on preoperative multimodal ultrasound of papillary thyroid carcinoma for predicting central lymph node metastasis

OBJECTIVES

To establish a nomogram for predicting central lymph node metastasis (CLNM) based on the preoperative clinical and multimodal ultrasound (US) features of papillary thyroid carcinoma (PTC) and cervical LNs.

METHODS

Overall, 822 patients with PTC were included in this retrospective study. A thyroid tumor ultrasound model (TTUM) and thyroid tumor and cervical LN ultrasound model (TTCLNUM) were constructed as nomograms to predict the CLNM risk. Areas under the curve (AUCs) evaluated model performance. Calibration and decision curves were applied to assess the accuracy and clinical utility.

RESULTS

For the TTUM training and test sets, the AUCs were 0.786 and 0.789 and bias-corrected AUCs were 0.786 and 0.831, respectively. For the TTCLNUM training and test sets, the AUCs were 0.806 and 0.804 and bias-corrected AUCs were 0.807 and 0.827, respectively. Calibration and decision curves for the TTCLNUM nomogram exhibited higher accuracy and clinical practicability. The AUCs were 0.746 and 0.719 and specificities were 0.942 and 0.905 for the training and test sets, respectively, when the US tumor size was ≤ 8.45 mm, while the AUCs were 0.737 and 0.824 and sensitivity were 0.905 and 0.880, respectively, when the US tumor size was > 8.45 mm.

CONCLUSION

The TTCLNUM nomogram exhibited better predictive performance, especially for the CLNM risk of different PTC tumor sizes. Thus, it serves as a useful clinical tool to supply valuable information for active surveillance and treatment decisions.

KEY POINTS

• Our preoperative noninvasive and intuitive prediction method can improve the accuracy of central lymph node metastasis (CLNM) risk assessment and guide clinical treatment in line with current trends toward personalized treatments. • Preoperative clinical and multimodal ultrasound features of primary papillary thyroid carcinoma (PTC) tumors and cervical LNs were directly used to build an accurate and easy-to-use nomogram for predicting CLNM. • The thyroid tumor and cervical lymph node ultrasound model exhibited better performance for predicting the CLNM of different PTC tumor sizes. It may serve as a useful clinical tool to provide valuable information for active surveillance and treatment decisions.

Establishing a Predictive Nomogram for Cervical Lymph Node Metastasis in Patients With Papillary Thyroid Carcinoma

Objectives

The purpose of this study was to establish a nomogram for predicting cervical lymph node metastasis (CLNM) in patients with papillary thyroid carcinoma (PTC).

Materials and Methods

A total of 418 patients with papillary thyroid carcinoma undergoing total thyroidectomy with cervical lymph node dissection were enrolled in the retrospective study from January 2016 to September 2019. Univariate and multivariate Logistic regression analysis were performed to screen the clinicopathologic, laboratory and ultrasound (US) parameters influencing cervical lymph nodes metastasis and develop the predicting model.

Results

CLNM was proved in 34.4% (144/418) of patients. In the multivariate regression analysis, Male, Age < 45 years, Tumor size > 20mm, multifocality, ambiguous boundary, extracapsular invasion and US-suggested lymph nodes metastasis were independent risk factors of CLNM (p < 0.05). Prediction nomogram showed an excellent discriminative ability, with a C-index of 0.940 (95% confidence interval [CI], 0.888-0.991), and a good calibration.

Conclusion

The established nomogram showed a good prediction of CLNM in patients with PTC. It is conveniently used and should be considered in the determination of surgical procedures.

Preoperative and pathological predictive factors of central lymph node metastasis in papillary thyroid microcarcinoma

OBJECTIVE

The aim of this study was to identify clinical and pathological markers of CLNM in persons with clinical lymph node-negative papillary thyroid microcarcinoma(PTMC).

MATERIALS AND METHODS

Retrospective data were analyzed from 804 PTMC clinically negative patients who were receiving thyroid surgery in the First Affiliated Hospital at Chongqing Medical University from January 2017 to December 2018. The CLNM-positive and CLNM-negative groups were categorised according to histological evidence of the central lymph node involvement, statistically, risk variables for CLNM were found.

RESULTS

324 (40.3%) individuals were diagnosed with CLNM. Sex (P=0.001), age at diagnosis (P<0.001), tumour size(P=0.029), microcaccificities presence (P=0.003), capsules discontinuity(P=0.002), multi-focality(P=0.001) and (ETE)extrathyroidal extension (P < 0.001) differed substantially from one positive CLNM group to the next. For multivariate analyses, women (odds ratio [OR] = 0.489), age [OR = 0.540] are the independent protective factors for CLNM; micro-cacification presence (OR = 1.511), discontinuity of capsules (OR= 2.056), multifocality(OR=1.486) and ETE(OR=10.613) are the independent risk factors for CLNM. Feature curves of the receiver were built and the AUC is 0.763. 32.1% percent (80 patients) of the 249 patients who did not have any of the four risk variables got CLNM. This contrasted with the incidence of CLNM in this research, which was as high as 49.1%.

CONCLUSIONS

CLNM has been connected with female sex, age - within 45 years, microcacification occurrences, capsule discontinuity, multifocality and extrathyroid expansion. The patients may benefit from the surgical decision of pCLND whether there are risk factors combined.

A Proposed Heterogeneous Ensemble Algorithm Model for Predicting Central Lymph Node Metastasis in Papillary Thyroid Cancer

Purpose

To develop a heterogeneous ensemble algorithm model to precisely predict central lymph node metastasis (CLNM), which can provide a reference value on controversial topics of performing prophylactic central lymph node dissection for patients with papillary thyroid cancer (PTC).

Methods

The study included patients with PTC who underwent an initial thyroid resection in a single-center medical institution between January 2014 and December 2018. A total of 18 variables, including clinical features and ultrasound (US) features, were used in the univariate analysis, multivariate analysis, and feature selection and were also used to develop a heterogeneous ensemble model based on five basic machine learning models, including extreme gradient boosting, k-nearest neighbors, random forest, gradient boosting, and AdaBoost. Moreover, a partial dependent plot was used to explain the heterogeneous ensemble model.

Results

The area under the receiver operating characteristic curve of the heterogeneous ensemble algorithm model was 0.67, which is significantly better than that of the basic machine models in predicting CLNM. All machine learning models performed better than US. Based on multivariate analysis and receiver operating characteristic curve analysis, age ≤33 years, tumor size ≥0.8 cm, US-suspected CLNM, and microcalcification were risk factors for CLNM, and anti-thyroid peroxidase antibody and serum thyroglobulin levels were favorable factors for CLNM.

Conclusion

The proposed heterogeneous ensemble algorithm model may be optimal tool to predict CLNM by integrating clinical and US features.

A Clinical Predictive Model of Central Lymph Node Metastases in Papillary Thyroid Carcinoma

BACKGROUND

Thyroid carcinoma is one of the most common endocrine tumors, and papillary thyroid carcinoma (PTC) is the most common pathological type. Current studies have reported that PTC has a strong propensity for central lymph node metastases (CLNMs). Whether to prophylactically dissect the central lymph nodes in PTC remains controversial. This study aimed to explore the risk factors and develop a predictive model of CLNM in PTC.

METHODS

A total of 2,554 patients were enrolled in this study. The basic information, laboratory examination, characteristics of cervical ultrasound, genetic test, and pathological diagnosis were collected. The collected data were analyzed by univariate logistic analysis and multivariate logistic analysis. The risk factors were evaluated, and the predictive model was constructed of CLNM.

RESULTS

The multivariate logistic analysis showed that Age (p < 0.001), Gender (p < 0.001), Multifocality (p < 0.001), BRAF (p = 0.027), and Tumor size (p < 0.001) were associated with CLNM. The receiver operating characteristic curve (ROC curve) showed high efficiency with an area under the ROC (AUC) of 0.781 in the training group. The calibration curve and the calibration of the model were evaluated. The decision curve analysis (DCA) for the nomogram showed that the nomogram can provide benefits in this study.

CONCLUSION

The predictive model of CLNM constructed and visualized based on the evaluated risk factors was confirmed to be a practical and convenient tool for clinicians to predict the CLNM in PTC.

A multi-institutional study of association of sonographic characteristics with cervical lymph node metastasis in unifocal papillary thyroid carcinoma

OBJECTIVE

Papillary thyroid carcinoma (PTC) is the most common pathological type of thyroid carcinoma, and is prone to cervical lymph node metastases (CLNM). We aim to evaluate the association between sonographic characteristics of PTC and CLNM before the initial surgery.

METHODS

Clinical information as well as ultrasonographic measurements and characteristics for 2376 patients from three hospitals were acquired in this retrospective cohort study. Univariate and multivariate logistic analysis were performed to predict CLNM in unifocal PTC patients. Receiver operating characteristic (ROC) curve was created to evaluate diagnostic performance.

RESULTS

Univariate analysis showed that gender, age, maximum tumor diameter and volume, cross-sectional and longitudinal aspect ratio, location, echogenicity, margin, and echogenic foci were independently associated with CLNM metastatic status (P < 0.05). Multivariate logistic analysis showed that gender, age, maximum tumor diameter and volume, cross-sectional aspect ratio (CSAR), location, echogenicity, margin, and echogenic foci were independent correlative factors; CSAR showed a significant difference for PTC2 to predict CLNM. The area under the curve (AUC) of the maximum tumor diameter, tumor volume, margin, and echogenic foci was 0.70, 0.69, 0.65, and 0.70, respectively. The multiple-variable linear regression model was constructed with an AUC of 0.77, a specificity of 73.4%, and a sensitivity of 72.3%. Kruskal-Wallis analysis for positive subgroups, maximum tumor diameter and volume, cross-sectional and longitudinal aspect ratio, margin, and echogenic foci showed statistical significance (P < 0.05).

CONCLUSIONS

Younger age (< 55 years), male, larger tumor, and echogenic foci were high risk factors for CLNM in patients with unifocal PTC. CSAR had a more effective predictive value for CLNM in patients with larger thyroid tumors. A larger tumor with irregular and punctate echogenic foci was also more prone to the lateral neck, and both central and lateral neck metastasis.

A prognostic nomogram for papillary thyroid cancer lymph node metastasis based on immune score

BACKGROUND

Papillary thyroid cancer (PTC) is the most common subtype of thyroid cancer and is characterized by an overall good prognosis and early-stage lymph node metastasis. The immune microenvironment is believed to play a crucial role in PTC initiation, progression and metastasis. However, to our knowledge, prognostic tools for thyroid cancer metastasis based on immune scores have not been adequately explored. This study aimed to construct a clinical nomogram to predict lymph node metastasis in patients with PTC.

METHODS

The genomic data and clinical-pathological characteristics of 447 PTC subjects were obtained from TCGA (The Cancer Genome Atlas data). Logistic regression models were performed for univariate and multivariate analyses to identify significant prediction factors. A prognostic nomogram was built based on the multivariate analysis results. The concordance index (C-index) and calibration curve were used to assess the predictive accuracy and discriminative ability of the model.

RESULTS

The patients were divided into two subgroups based on immune scores. We found that patients with high immune scores had significantly higher lymph node metastasis risks (OR and 95% confidence interval [CI]: 1.774[1.130-2.784]) than those with low immune scores. The C-index for lymph node metastasis was 0.722 (95% CI, 0.671-0.774), which had a favorable performance for clinical prediction. The calibration curve for lymph node metastasis showed significant agreement between the nomogram prediction and actual observation.

CONCLUSION

High immune scores are significantly correlated with higher lymph node metastasis risk in patients with PTC. Immune score-based prognostic nomograms may help to predict lymph node metastasis and have potential clinical application possibilities.

A Novel and Effective Model to Predict Skip Metastasis in Papillary Thyroid Carcinoma Based on a Support Vector Machine

INTRODUCTION

Skip metastasis, referred to as lymph node metastases to the lateral neck compartment without involvement of the central compartment, is generally unpredictable in papillary thyroid carcinoma (PTC). This study aims to establish an effective predictive model for skip metastasis in PTC.

METERIALS AND METHODS

Retrospective analysis was performed of clinical samples from 18192 patients diagnosed with thyroid cancer between 2016 to 2020. The First Affiliated Hospital of Wenzhou Medical University. The lateral lymph node metastasis was occureed in the training set (630 PTC patients) and validation set (189 PTC patients). The univariate and multivariate analyses were performed to detect the predictors of skip metastasis and the support vector machine (SVM) was used to establish a model to predict skip metastasis.

RESULTS

The rate of skip metastasis was 13.3% (84/631). Tumor size (≤10 mm), upper location, Hashimoto's thyroiditis, extrathyroidal extension, absence of BRAFV600E mutation, and less number of central lymph node dissection were considered as independent predictors of skip metastasis in PTC. For the training set, these predictors performed with 91.7% accuracy, 86.4% sensitivity, 92.2% specificity, 45.2% positive predictive value (PPV), and 98.9% negative predictive value (NPV) in the model. Meanwhile, these predictors showed 91.5% accuracy,71.4% sensitivity, 93.1% specificity, 45.5% PPV, and 97.6% NPV in validation set.

CONCLUSION

This study screened the predictors of the skip lateral lymph node metastasis and to establish an effective and economic predictive model for skip metastasis in PTC. The model can accurately distinguish the skip metastasis in PTC using a simple and affordable method, which may have potential for daily clinical application in the future.

Outcomes of nonsuspicious contralateral nodules with active surveillance after lobectomy in patients with papillary thyroid carcinoma

OBJECTIVE

To observe the outcomes of nonsuspicious contralateral nodules with active surveillance in patients with papillary thyroid carcinoma (PTC).

METHODS

4pt?>Consecutive patients who underwent lobectomy for PTC were retrospectively reviewed. Patients with one or more nodules with nonsuspicious ultrasonography (US) features in the contralateral lobe were included.

RESULTS

Two hundred and eighty-three patients were included. All patients underwent thyroid lobectomy with ipsilateral prophylactic central neck dissection. A total of 123 patients (43.5%) were classified as ATA low-risk, and 160 patients (56.5%) were classified as intermediate-risk. The median size of the contralateral nodules was 3 mm (range, 2 to 16 mm). After a period of follow-up, the median size change of contralateral nodules was 0 mm (range, -7 to 8 mm). Eight patients (2.8%) had nodule growth >3 mm, 223 patients (78.8%) had stable or decreased nodules, and 52 patients (18.4%) had no detectable nodules. Nodules in 24 patients had suspicious US features, 16 of which were diagnosed with PTMC by either cytology after FNA (in 7 patients) or histopathology after completion thyroidectomy (in 9 patients). Another four patients received completion thyroidectomy for ipsilateral cervical lymph node metastasis. The 5-year residual lobe recurrence (RLR) rate and recurrence-free survival (RFS) rate were 7.4% and 89.8%, respectively. Multivariate analysis showed that multifocality and ATA intermediate-risk were independent predictors for RLR (HR4.083, 95%CI 1.480-11.261, P = 0.007; HR 6.045, 95%CI 1.370-26.662, P = 0.017, respectively) and RFS (HR 5.240, 95%CI 2.114-12.991, P < 0.001; HR 5.223, 95%CI 1.353-17.765, P = 0.008, respectively).

CONCLUSIONS

Active surveillance for nonsuspicious contralateral nodules in patients with low-risk and selected intermediate-risk PTC is safe. Multifocality and ATA intermediate-risk are predicters for recurrence. Early detection and salvage surgery are effective.

Total tumor diameter is a better indicator of multifocal papillary thyroid microcarcinoma: A propensity score matching analysis

BACKGROUND

Accurate evaluation of the risk of papillary thyroid microcarcinoma (PTMC) is the key to treatment. However, the maximum diameter (MD), which is currently used in various staging systems, may not truly reflect the aggressiveness of multifocal tumors.

METHODS

Clinical and pathological data for 1001 patients with papillary thyroid carcinoma who underwent surgery at the Hangzhou First People's Hospital were retrospectively analyzed. First, the relationship between total tumor diameter (TTD) and clinicopathological features in multifocal PTMC was explored. Then, patients were divided into subgroups according to the TTD. The baseline was consistent after using the propensity score matching method, and the differences between groups were compared. In addition, the effectiveness of TTD and MD in evaluating central lymph node metastasis (CLNM) was analyzed and compared.

RESULTS

TTD is associated with a range of clinicopathological features, including lymph node metastasis, extrathyroidal extension, and risk stratification. Assuming the same MD and number of foci, the invasiveness of multifocal PTMC with TTD >1 cm was significantly higher than that with TTD <1 cm, and even higher than unifocal non-PTMC. Moreover, the efficiency of TTD in predicting CLNM was also significantly higher than that of MD.

CONCLUSION

For multifocal PTMC, TTD is a more realistic indicator of tumor biological characteristics than MD. The aggressiveness of PTMC with TTD >1 cm was significantly enhanced, and surgical treatment should be actively sought in such cases.

The Differences Between Multifocal and Unifocal Papillary Thyroid Carcinoma in Unilateral Lobe: A Meta-Analysis

Background

As many inconsistent reports on the clinical manifestations and prognosis between unilateral unifocal PTC (UUPTC) and unilateral multifocal PTC (UMPTC), identifying the difference should guide management. The purpose of this study was to investigate other additional differences between UUPTC and UMPTC in addition to their difference in the number of cancer foci.

Data Sources

A systematic literature search was conducted in the PubMed and Web of Science databases for relevant studies published before December 31, 2020. Their reference lists were also reviewed.

Review Methods

Two reviewers independently extracted data and assessed the quality of eligible studies. Studies on patients who underwent an open thyroidectomy with or without neck dissection were included. Data were analyzed using the RevMan 5.3 software.

Results

Fifteen studies comprising 9,665 patients were selected for the meta-analysis. UMPTC occurred in 10% to 36% of all PTC cases. There were no significant differences between UMPTC and UUPTC patients in age, gender, tumor size, and extrathyroidal extension (ETE). However, significant differences (P < 0.05) between UMPTC and UUPTC patients were observed in central lymph node metastasis (CLNM), lateral lymph node metastasis (LLNM), tumor-node-metastasis (TNM) stage I+II, TNM stage III+IV, the recurrence/persistence of the UMPTC group after total thyroidectomy and overall recurrence/persistence.

Conclusion

UMPTC patients are more likely to have CLNM, LLNM, more advanced TNM stage, and recurrence/persistence than UUPTC patients. Compared with UUPTC, UMPTC patients should undergo central lymph node dissection, and pay more attention to LLNM, TNM stage and recurrence/persistence during the follow-up.

Characteristics of Malignant Thyroid Tumors: A Retrospective Study on 320 Patients

Papillary thyroid cancer accounts for 80-85% of diagnosed thyroid cancers, while follicular, medullary, and anaplastic cancers are diagnosed significantly less frequently. This study aimed to show the characteristics of malignant thyroid tumors. In this retrospective study, we analyzed data from 320 patients who underwent thyroid surgery from January 2018 to December 2019. We recorded and statistically analyzed basic demographic data, data of the cytological and pathohistological findings, and tumor characteristics (size, multifocality, extrathyroidal and lymphovascular invasion). Thyroid cancer was diagnosed in 95 patients. The incidence of thyroid cancer was higher in women than in men, but without a significant difference (p=0.46). There was a significant difference between preoperative cytological findings and definitive pathohistological diagnosis (p=0.001). There was no significant difference between genders in tumor size, extrathyroidal and lymphovascular invasion, and multifocality. There were significantly more thyroid cancers with a lymphovascular invasion that were less than 2 cm in size (p=0.04). In our opinion, it is important to emphasize the value of early diagnostics and analysis of the malignant tumor characteristics that are major prognostic factors for survival in patients with thyroid cancer.

A UK based two-centre review of multifocality and its role in the treatment of papillary thyroid cancer

INTRODUCTION

Multifocality is increasingly observed in papillary thyroid carcinoma (PTC) due to improvements in imaging and histopathological analysis. However, its significance in management, particularly as a sole risk-factor, remains controversial. This study aimed to investigate the prognostic value of multifocality in predicting recurrence following thyroid lobectomy in a contemporary group of PTC patients managed in the UK.

METHODS

Patients with PTC in NHS Lothian (2009-19) and Guys and St Thomas NHS Foundation Trust (2012-19) were identified. Categorical variables were compared using Chi-squared or Fisher's exact test. Five-year recurrence free survival (RFS) were analysed using Kaplan-Meier method and compared using log-rank.

RESULTS

Of 828 patients; 492 (59%) had unifocal and 336 (41%) multifocal disease on final pathology. A higher rate of pathological nodal disease (22%v36%,p < 0.001), total thyroidectomy (TT) (78%v92%,p < 0.001) and radioactive iodine (RAI) (57%v75%,p < 0.001) was demonstrated in patients with multifocality. With a median follow-up of 50 months, overall 5-year RFS was 96.5%; 96.5% for unifocal versus 96.6% for multifocal disease (p = 0.695). Recurrence was not shown to be associated with multifocality on either univariate or multivariate analysis. Amongst patients with T1/2N0M0 disease (n = 341), more patients were treated with TT and RAI with multifocal compared to unifocal disease (<0.001). Only two patients within this group recurred during follow up, both of whom had multifocal disease and were treated with TT and RAI (5yRFS100%v98.1%,p = 0.051).

CONCLUSION

Multifocality is a common feature of PTC but does not appear to be an independent predictor of outcome. Therefore, treatment intensification on the basis of multifocality alone seems unwarranted.

Analyze and compare the predictors of ipsilateral central lymph node metastasis in papillary thyroid carcinoma with cT1a and cT1b stage

PURPOSE

Central lymph node metastasis (CLNM) is common in papillary thyroid carcinoma (PTC). The aim of this study was to compare the cT1a and cT1b stages of PTC and to analyze the predictive factors of ipsilateral central lymph node metastasis (CLNM).

METHODS

In total, 212 PTC (cT1N0) patients underwent hemi-thyroidectomy with ipsilateral central lymph node dissection (CLND) between 2019 and 2020 in our hospital. Univariate and multivariate analyses identified the predictive factors for CLNM of PTC (cT1aN0 and cT1bN0), and compared the differences between the two stages.

RESULTS

The total rate of ipsilateral CLNM was 31.13% (66/212), and the ipsilateral CLNM rate in cT1b stage was higher than that in cT1a stage (48.84% vs. 26.63%), with significant differences (p = 0.005). cT1b stage was more prone to capsule invasion than cT1a stage (41.86% vs. 2.37%), with significant differences (p‹0.001). The multivariate analysis showed that tumor size (n > 5 mm) was an independent predictive factor for CLNM in cT1a stage (p = 0.002), with an odds ratio (OR) of 0.228 (95% confidence interval (95% CI): 0.079-0.655). Capsular invasion (p = 0.048) and tumors located in the middle and lower parts (p = 0.022) were independent predictive factors for CLNM in cT1b stage, with ORs of 0.157 (95% CI: 0.034-0.724) and 0.075 (95% CI: 0.007-0.847), respectively.

CONCLUSIONS

The rate of CLNM increases with increase of tumor size. Patients in cT1b stage are more prone to capsule invasion and CLNM. For the cT1b stage of PTC, predictive factors should be correctly evaluated to guide surgical treatment for PTC patients.

Does Multifocal Papillary Thyroid Microcarcinoma With a Total Tumor Diameter >1 cm Indicate Poor Biological Behavior? The Evidence is Insufficient

OBJECTIVE

Multifocal cancer is common in papillary thyroid microcarcinoma (PTMC). Our aim was to investigate the correlation between multifocal PTMC, total tumor diameter (TTD), and clinicopathologic features.

METHODS

In total, 206 patients were included and grouped as stage cT1a or cT1b. The primary tumor diameter and TTD (the sum of the maximal diameter of each focus) were calculated. These patients were further subgrouped as TTD ≤1 cm or 1 cm < TTD ≤ 2 cm. The relationships of clinicopathological features between these groups were analyzed.

RESULTS

Multifocal cancer was more likely to occur with stage cT1a than stage cT1b (P = .028). Stage cT1b papillary thyroid carcinoma was more prone to central lymph node metastasis (CLNM) and capsular invasion than stage cT1a. There was no difference in clinicopathological factors, such as sex, age, CLNM, number of CLNMs, capsular invasion, BRAF mutation, or recurrence between the multifocal PTMC and TTD >1 cm and primary tumor diameter + TTD ≤1 cm groups. Comparing stage cT1a and cT1b tumors with a 1 cm < TTD ≤ 2 cm using a multivariate analysis, stage cT1b tumors were more prone to capsular invasion than stage cT1a tumors, with an odds ratio of 19.013 (95% confidence interval, 2.295-157.478), but there was no significant correlation with CLNM.

CONCLUSION

Stage cT1b tumors are more prone to capsular invasion and CLNM than than stage cT1a tumors. For multifocal PTMC, calculating the TTD to evaluate adverse biological behavior is insufficient and limited, and further research is needed.

Clinical Study of Ultrasonographic Risk Factors for Central Lymph Node Metastasis of Papillary Thyroid Carcinoma

BACKGROUND

Thyroid cancer is the most common malignancy of the endocrine system worldwide. Papillary thyroid cancer (PTC) is the most common pathologic type. The preoperative diagnosis of PTC and central lymph node metastasis (CLNM) or metastatic tendency is of great clinical significance to the diagnosis, treatment and prognosis of these patients. This study was conducted to investigate the correlation between ultrasound features and central CLNM of PTC.

METHODS

This study retrospectively analyzed patients who underwent PTC surgery and central lymph node dissection in the Department of Surgery, Beijing Tiantan Hospital, from January 2019 to February 2020. According to the inclusion and exclusion criteria, data from 136 patients were ultimately included, and the clinical and ultrasonic data of the patients were analyzed by multivariate regression to evaluate the correlation among grayscale ultrasound (US), superb microvascular imaging (SMI) and contrast-enhanced ultrasound (CEUS) features of thyroid nodules and CLNM of PTCs.

RESULTS

The multivariate analysis showed that tumor size, multifocality, microcalcification characteristics, SMI vascularization, and CEUS evaluation of contact with the adjacent capsule were correlated with PTC metastasis (P=0.008, P=0.001, P=0.028, P=0.041, and P< 0.001, respectively). Comparisons of the area under the ROC curves revealed that the area under the ROC curve of the degree of nodular invasion into the thyroid capsule was the largest (AUC: 0.754). The sensitivity and specificity for evaluating CLNM of PTC were 67.7% and 83.1%, respectively.

CONCLUSIONS

Ultrasound characteristics of the following features are associated with a high risk of lymph node metastasis in PTCs: maximum diameter of nodules ≥1 cm, multifocality, ≥5 microcalcifications, abundant blood flow of SMI in nodules and nodule contact with the thyroid capsule ≥25% under CEUS. Ultrasound has clinical value in the preoperative evaluation of CLNM of PTCs.

Risk Factors for Contralateral Occult Carcinoma in Patients With Unilateral Papillary Thyroid Carcinoma: A Retrospective Study and Meta-Analysis

BACKGROUND

Bilateral lesions are common in papillary thyroid carcinoma (PTC). For patients with unilateral PTC, occult carcinoma that is not detected preoperatively, but pathologically after surgery, might remain in the contralateral lobe. In this situation, inadequate surgical extent could cause relapse and even lead to re-operation. Here, we explore the frequency and investigate the risk factors of contralateral occult PTC in unilateral PTC through a retrospective study conducted by our team and published articles online, respectively.

METHODS

We collected the patients' clinical data in our hospital, whose cancer was determined to be confined to the unilateral lobe by preoperative image examination (N = 204). These patients underwent initially total or near-total thyroidectomy and included their clinical data in the meta-analysis. We searched related literature in the PubMed, Embase, MEDLINE, Cochrane, and Web of Science databases until December 7, 2020, in order to perform a meta-analysis. The relevant articles were examined and the eligible studies were included to assess the association between clinicopathologic factors and contralateral occult PTC.

RESULTS

The meta-analysis included nine studies (involving 4347 patients). Of these, eight studies were from the databases, and one study was our retrospective data. The meta-analysis showed that the prevalence of contralateral occult PTC was 26.6% in all patients. A tumor size > 1 cm, ipsilateral multifocality, contralateral benign nodule, and central lymph node metastasis were significantly associated with contralateral occult PTC. In contrast, sex, age, ETE, capsular invasion, BRAF mutation, Hashimoto thyroiditis, and lateral lymph node metastasis were insignificantly associated with contralateral occult PTC.

CONCLUSION

The meta-analysis identified a tumor size > 1 cm, ipsilateral multifocality, contralateral benign nodule, and CLNM as being significant risk factors for contralateral occult PTC. These findings may guide the extent of surgery in unilateral PTC patients.

A Nomogram Based on Clinical and Ultrasound Characteristics to Predict Central Lymph Node Metastasis of Papillary Thyroid Carcinoma

BACKGROUND

The status of lymph nodes in the central compartment is crucial to determining the surgical strategies for papillary thyroid carcinoma (PTC). We aimed to develop a nomogram for predicting central lymph node metastasis (CLNM).

METHODS

A total of 886 PTC patients who underwent total thyroidectomy or lobectomy with central neck dissection (CND) from July 2019 to June 2020 were retrospectively retrieved. Clinical and ultrasound features were collected. Univariate and multivariate analysis were performed to determine risk factors of CLNM. A nomogram for predicting CLNM was developed, internal and external calibration was performed for the established model.

RESULTS

Variables (sex, chronic lymphocytic thyroiditis, tumor size, the number of foci, tumor location, margin) significantly associated with CLNM were included in the nomogram. The nomogram showed excellent calibration in the training group and validation group, with area under curves of 0.806 (95% CI, 0.771 to 0.825), and 0.799 (95% CI, 0.778-0.813) respectively.

CONCLUSION

Through this accurate and easy-to-use nomogram, the possibility of CLNM can be objectively quantified preoperatively. Clinicians can use this nomogram to evaluate the status of lymph nodes in PTC patients and consider prophylactic CND for those with high scores.

Computed Tomography-Based Radiomics Model to Predict Central Cervical Lymph Node Metastases in Papillary Thyroid Carcinoma: A Multicenter Study

OBJECTIVES

This study aimed to develop a computed tomography (CT)-based radiomics model to predict central lymph node metastases (CLNM) preoperatively in patients with papillary thyroid carcinoma (PTC).

METHODS

In this retrospective study, 678 patients with PTC were enrolled from Yantai Yuhuangding Hot3spital (n=605) and the Affiliated Hospital of Binzhou Medical University (n=73) within August 2010 to December 2020. The patients were randomly divided into a training set (n=423), an internal test set (n=182), and an external test set (n=73). Radiomics features of each patient were extracted from preoperative plain scan and contrast-enhanced CT images (arterial and venous phases). One-way analysis of variance (ANOVA) and least absolute shrinkage and selection operator algorithm were used for feature selection. The K-nearest neighbor, logistics regression, decision tree, linear-support vector machine (linear-SVM), Gaussian-SVM, and polynomial-SVM algorithms were used to establish radiomics models for CLNM prediction. The clinical risk factors were selected by ANOVA and multivariate logistic regression. Incorporated with clinical risk factors, a combined radiomics model was established for the preoperative prediction of CLNM in patients with PTCs. The performance of the combined radiomics model was evaluated using the receiver operating characteristic (ROC) and calibration curves in the training and test sets. The clinical usefulness was evaluated through decision curve analysis (DCA).

RESULTS

A total of 4227 radiomic features were extracted from the CT images of each patient, and 14 non-zero coefficient features associated with CLNM were selected. Four clinical variables (sex, age, tumor diameter, and CT-reported lymph node status) were significantly associated with CLNM. Linear-SVM led to the best prediction model, which incorporated radiomic features and clinical risk factors. Areas under the ROC curves of 0.747 (95% confidence interval [CI] 0.706-0.782), 0.710 (95% CI 0.634-0.786), and 0.764 (95% CI 0.654-0.875) were obtained in the training, internal, and external test sets, respectively. The linear-SVM algorithm also showed better sensitivity (0.702 [95% CI 0.600-0.790] vs. 0.477 [95% CI 0.409-0.545]) and accuracy (0.670 [95% CI 0.600-0.738] vs. 0.642 [95% CI 0.569-0.712]) than an experienced radiologist in the internal test set in the combined radiomics model. The calibration plot reflected a favorable agreement between the actual and estimated probabilities of CLNM. The DCA indicated the clinical usefulness of the combined radiomics model.

CONCLUSION

The combined radiomics model is a non-invasive preoperative tool that incorporates radiomic features and clinical risk factors to predict CLNM in patients with PTC.

Patient and tumor factors contributing to distant metastasis in well-differentiated thyroid cancer: a retrospective cohort study

BACKGROUND

Distant metastasis in thyroid cancer significantly reduces survival in patients with well-differentiated thyroid carcinoma (WDTC). There is limited information available to clinicians regarding pathological features that confer a higher risk of distant metastasis (DM). This study aimed to identify patient and tumor factors that were associated with the development of DM over time in patients with WDTC.

METHODS

A retrospective cohort analysis of patients with WDTC (n = 584) at our institution was performed between 2007 and 2017. A total of 39 patients with DM and 529 patients with no DM (NDM) were included. Patient demographics, tumor characteristics and patient survival were compared between the DM and NDM groups using a univariate analysis. Multivariate Cox-proportional hazards model was used to evaluate the risk of developing distant metastasis over time. Kaplan-Meier analysis was used to compare survival between the DM and NDM groups.

RESULTS

Distant metastasis had a substantial impact on disease-specific survival (DSS) at 5 and 10-years in the DM group; 71.0% (SE 8.4%) and 46.9% (SE 11.6%) respectively, compared to 100% survival in the NDM group (p < 0.001). The DM group had significantly higher proportions of males, lymphovascular invasion (LVI), nodal metastasis (NM), large tumor size (TS), extrathyroidal extension (ETE), positive resection margins, multifocality, follicular thyroid cancer (FTC), tall cell variant of papillary thyroid cancer (PTC), and Hurthle cell carcinoma (HCC), when compared to the NDM group (p < 0.05). A TS ≥ 2 cm (Hazard Ratio (HR) 1.370), NM (HR 3.806) and FTC (HR 7.068) were associated with a significantly increased hazard of developing distant metastasis in patients with WDTC.

CONCLUSIONS

TS ≥ 2 cm, NM and FTC are associated with a significantly increased propensity for developing DM in our cohort of WDTC patients.

Thyroid Lobectomy for Low to Intermediate Risk Differentiated Thyroid Cancer

Simple Summary

Total thyroidectomy used to be recommended for all thyroid cancers. We now know that some thyroid cancers have a relatively low risk of recurrence. Today, for some of these cancers, depending on the type of tumor, its’ size and other tumor characteristics, a thyroid lobectomy (or hemithyroidectomy) can be performed without increasing the patient’s risk of cancer recurrence. Thyroid lobectomy has the advantages of having less risk of surgical complications and a less frequent need for thyroid hormone replacement therapy. This approach is not optimal for all thyroid cancers, however, and careful tumor and patient selection are necessary. This review explains the rationale and criteria for patient selection for thyroid lobectomy for selected thyroid cancers.

Abstract

Many recent publications and guidelines have promoted a “more is less” approach in terms of treatment for low to intermediate risk differentiated thyroid cancer (DTC), which comprise the vast majority of thyroid cancers: less extensive surgery, less radioactive iodine, less or no thyroid hormone suppression, and less frequent or stringent follow-up. Following this approach, thyroid lobectomy has been proposed as a means of decreasing short- and long-term postoperative morbidity while maintaining an excellent prognosis for tumors meeting specific macroscopic and microscopic criteria. This article will examine the pros and cons of thyroid lobectomy for low to intermediate risk cancers and discuss, in detail, criteria for patient selection and oncological outcomes.

Influence of Tumor Number on Clinicopathologic Features and Outcomes of Patients With Papillary Thyroid Carcinoma

OBJECTIVES

The purpose of this study was to investigate the significance of tumor number on clinicopathologic factors and outcomes of patients with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively analyzed 667 patients with PTC. We compared clinicopathologic features of patients with a different tumor number. Cox proportional hazards model was used to analyze risk factors of recurrence.

RESULTS

In papillary thyroid microcarcinoma (PTMC), the increase in the number of tumor foci was related to a higher risk of minimal extrathyroidal extension (ETE) and lymphovascular invasion (P < .05). Patients with PTMC with four or more foci had a significantly higher risk of central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) than patients with solitary tumors (P < .05). Patients with macro-PTC with four or more foci and with three foci had a higher risk of gross ETE and lymphovascular invasion than patients with solitary tumors (P < .05). The increase in the tumor number was related to a higher risk of CLNM in macro-PTC (P < .05). The number of foci was the independent predictor of recurrence in patients with macro-PTC (P < .05).

CONCLUSIONS

An increase in the number of tumors was associated with an increased risk of aggressive clinicopathologic features in PTMC and macro-PTC. The number of tumor foci could influence risk of recurrence in macro-PTC.

2020 Chinese guidelines for ultrasound malignancy risk stratification of thyroid nodules: the C-TIRADS

Thyroid nodules are very common all over the world, and China is no exception. Ultrasound plays an important role in determining the risk stratification of thyroid nodules, which is critical for clinical management of thyroid nodules. For the past few years, many versions of TIRADS (Thyroid Imaging Reporting and Data System) have been put forward by several institutions with the aim to identify whether nodules require fine-needle biopsy or ultrasound follow-up. However, no version of TIRADS has been widely adopted worldwide till date. In China, as many as ten versions of TIRADS have been used in different hospitals nationwide, causing a lot of confusion. With the support of the Superficial Organ and Vascular Ultrasound Group of the Society of Ultrasound in Medicine of the Chinese Medical Association, the Chinese-TIRADS that is in line with China's national conditions and medical status was established based on literature review, expert consensus, and multicenter data provided by the Chinese Artificial Intelligence Alliance for Thyroid and Breast Ultrasound.