Predicting factors for central or lateral lymph node metastasis in conventional papillary thyroid microcarcinoma

Advances in nanobubbles for cancer theranostics: Delivery, imaging and therapy

Maximizing treatment efficacy and forecasting patient prognosis in cancer necessitates the strategic use of targeted therapy, coupled with the prompt precise detection of malignant tumors. Theutilizationof gaseous systems as an adaptable platform for creating nanobubbles (NBs) has garnered significant attention as theranostics, which involve combining contrast chemicals typically used for imaging with pharmaceuticals to diagnose and treattumorssynergistically in apersonalizedmanner for each patient. This review specifically examines the utilization of oxygen NBsplatforms as a theranostic weapon in the field of oncology. We thoroughly examine the key factors that impact the effectiveness of NBs preparations and the consequences of these treatment methods. This review extensively examines recent advancements in composition schemes, advanced developments in pre-clinical phases, and other groundbreaking inventions in the area of NBs. Moreover, this review offers a thorough examination of the optimistic future possibilities, addressing prospective methods for improvement and incorporation into widely accepted therapeutic practices. As we explore the ever-changing field of cancer theranostics, the incorporation of oxygen NBs appears as a promising development, providing new opportunities for precision medicine and marking a revolutionary age in cancer research and therapy.

More aggressive biological behavior in pediatric than in adult papillary thyroid carcinoma

OBJECTIVE

Papillary thyroid carcinoma (PTC) remains a common malignancy of the endocrine system in children and adolescents. This study aimed to investigate the differences in clinical characteristics between children and adults with PTC.

METHODS

A total of 360 patients [ 308 adults (≥20 years) and 52 children and adolescents (<20 years)] with PTC who underwent thyroid surgery in our center from 2017 to 2022 were retrospectively analyzed. Statistical analysis and comparisons of the clinicopathological data and tumor characteristics between children and adults were performed.

RESULTS

Among all enrolled patients, the mean tumor diameter was 26.21 ± 12.72 mm in the pediatric group, while that in the adult group was 11.62 ± 10.21 mm, which was a significant difference (p < 0.001). Pediatric patients were more prone to central lymph node metastasis (90.38% vs. 49.35%, p<0.001), lateral lymph node metastasis (78.85% vs. 45.7%, p<0.001), capsular invasion (90.38% vs. 63.96%, p<0.001) and extrathyroidal extension (61.54% vs. 15.26%, p＜0.001) than adult patients. However, the pediatric group had a lower BRAFV600E mutation rate (54.76% vs. 87.7%, p < 0.001) and lower incidence of Hashimoto's thyroiditis (15.38% vs. 30.84%, p = 0.023) than the adult group. There were no significant differences in clinicopathological factors, such as sex, multifocality and hypothyroidism.

CONCLUSIONS

Pediatric patients were more likely to present with advanced disease at diagnosis, including larger tumor volume, more lymph node metastasis, more extensive local invasion, and lower rates of BRAF mutation and concomitant Hashimoto's thyroiditis. Therefore, appropriate surgical management and comprehensive treatment decisions are needed for pediatric patients with PTC.

Development and Validation of a Dual-Energy CT-Based Model for Predicting the Number of Central Lymph Node Metastases in Clinically Node-Negative Papillary Thyroid Carcinoma

RATIONALE AND OBJECTIVES

This study aimed to develop and validate a dual-energy CT (DECT)-based model for preoperative prediction of the number of central lymph node metastases (CLNMs) in clinically node-negative (cN0) papillary thyroid carcinoma (PTC) patients.

MATERIALS AND METHODS

Between January 2016 and January 2021, 490 patients who underwent lobectomy or thyroidectomy, CLN dissection, and preoperative DECT examinations were enrolled and randomly allocated into the training (N = 345) and validation cohorts (N = 145). The patients' clinical characteristics and quantitative DECT parameters obtained on primary tumors were collected. Independent predictors of> 5 CLNMs were identified and integrated to construct a DECT-based prediction model, for which the area under the curve (AUC), calibration, and clinical usefulness were assessed. Risk group stratification was performed to distinguish patients with different recurrence risks.

RESULTS

More than 5 CLNMs were found in 75 (15.3%) cN0 PTC patients. Age, tumor size, normalized iodine concentration (NIC), normalized effective atomic number (nZeff) and the slope of the spectral Hounsfield unit curve (λHu) in the arterial phase were independently associated with> 5 CLNMs. The DECT-based nomogram that incorporated predictors demonstrated favorable performance in both cohorts (AUC: 0.842 and 0.848) and significantly outperformed the clinical model (AUC: 0.688 and 0.694). The nomogram showed good calibration and added clinical benefit for predicting> 5 CLNMs. The KaplanMeier curves for recurrence-free survival showed that the high- and low-risk groups stratified by the nomogram were significantly different.

CONCLUSION

The nomogram based on DECT parameters and clinical factors could facilitate preoperative prediction of the number of CLNMs in cN0 PTC patients.

Risk prediction for <1 cm lateral lymph node metastasis in papillary thyroid microcarcinoma

Background

Because the diameter of the suspicious lymph nodes is less than 1 cm and adjacent to important structures in the neck, the diagnosis of small LLNM is important but difficult without the help of fine needle aspiration (FNA). There are no relevant reports of risk factors that predict the risk of suspicious <1 cm LLNM.

Methods

A total of 159 PTMC patients with suspicious <1 cm LLNM were included in the study. Multivariate logistic regression analysis was used to identify ultrasound independent predictors of LLNM. A predictive model was developed according to multivariate logistic regression and evaluated by Hosmer-Lemeshow fit test.

Results

Age ≤ 38 years old, the largest PTMC was located in the upper part, and the presence of liquefaction or microcalcification in suspicious lymph nodes were independent risk factors for LLNM (univariate analysis P = 0.00, 0.00, 0.00; multivariate analysis P = 0.00, 0.02, 0.00. OR = 4.66 [CI: 1.78-12.21], 3.04 [CI: 1.24-7.46], 6.39 [CI: 1.85-22.00]). The predictive model for the diagnosis of suspicious <1 cm lymph nodes was established as: P = ex/(1 + ex). X = -1.29 + (1.11 × whether the largest tumor is located in the upper part) + (1.54 × whether the age is ≤ 38 years) + (1.85 × whether the suspicious lymph nodes have liquefaction/microcalcification). The Hosmer-Lemeshow fit test was used to test the predicted ability, and it found that the predictive model had a good fit and prediction accuracy (X2 = 6.214, P = 0.623 > 0.05). Chi squared trend analysis showed that the increase in the number of risk factors gradually increased the malignancy possibility of suspicious <1 cm lymph nodes (chi squared trend test, P = 0.00).

Conclusions

Age ≤ 38 years old, the largest PTMC located in the upper part, and the presence of liquefaction or microcalcification in suspicious lymph nodes were independent risk factors for suspicious <1 cm LLNM in PTMC patients. Our result show that it is feasible to evaluate the malignant possibility of these lymph nodes using the number of risk factors.

The role of multifocality in predicting central lymph node metastasis in initially treated 18-55 years old female patients with unilateral papillary thyroid microcarcinoma

Objective

To determine the predictive ability of multifocality for central lymph node metastasis in initially treated 18-55 years old female patients with unilateral papillary thyroid microcarcinoma.

Study design

Retrospective review.

Setting

Tertiary medical center.

Methods

We retrospectively collected clinical data from initially treated papillary thyroid microcarcinoma (PTMC) patients at Cancer Hospital Chinese Academy of Medical and sciences between January 1st, 2018, and December 31st, 2018. Data from 975 initially treated 18-55 years old female patients with unilateral PTMC was collected. We also collected data from 340 initially treated 18-55 years old male patients with unilateral PTMC patients to compare the results between genders. Clinicopathological factors associated with central lymph node metastasis (CLNM) were investigated by univariate and multivariate analysis.

Results

(1) In the female group, there were 196 (20.1%) cases that had tumor multifocality, including 126 (12.9%) with 2 foci and 70 (7.2%) with >2 foci. The risk of CLNM in patients with 2 foci was not significantly higher than patients with 1 focus (37.3% vs 38.6%, P=0.775). However, diagnosed with >2 foci were independently and positively correlated with CLNM (OR=2.708, 95%CI=1.592-4.607, P<0.001), as was tumor diameter >0.55cm (OR=2.047, 95%CI=1.535-2.730, P<0.001). (2) In the male group, the risk of CLNM with 2 foci was significantly higher than 1 focus (P=0.008). Compared to female patients, the risk of CLNM was significantly higher in patients with 1 focus (P<0.001) or 2 foci (P<0.001).

Conclusion

In summary, the risk of CLNM in patients with 2 foci was not significantly higher than patients with 1 focus, while multifocality with over 2 foci was an independent risk factor of CLNM. Therefore, multifocality in this subgroup should not be simply defined as "more than 1 focus". Future models that include multifocality as a predictive factor for cervical lymph node metastasis could consider stratifying the cohort into smaller subgroups for more accurate conclusions.

Association between iodine nutrition and cervical lymph node metastasis of papillary thyroid microcarcinoma

We aimed to investigate the association between iodine intake and nodal metastasis stratified by central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) of papillary thyroid microcarcinoma (PTMC). Urinary iodine concentration (UIC) and clinicopathological characteristics were used to identify factors associated with CLNM and LLNM using logistic regression analysis. A sum of 3,858 PTMC patients were enrolled. The median UIC (MUI) of patients with CLNM or LLNM was not statistically different from those without nodal metastasis. Male patients had a higher MUI than females (183.4 μg/L vs. 173.6 μg/L). Female patients with extracapsular extension had a higher MUI than those without it (210.0 μg/L vs. 172.1 μg/L). Male patients with LLNM had a significantly lower MUI than those without LLNM (134.7 μg/L vs. 187.9 μg/L). Female patients with more than adequate iodine intake were more likely to present with CLNM and extrathyroidal extension than those with adequate iodine intake with an odds ratio (95% confidence interval) of 1.23 (1.01-1.51) and 1.59 (1.09-2.32) after adjustment. Iodine nutrition was not found to be associated with LLNM. In addition, patients with a younger age, larger tumors, extrathyroidal extension, and intrathyroidal spread were more likely to be CLNM, whereas nodular goiter presented with a protective factor; CLNM was the only factor associated with LLNM of PTMC in both genders. In conclusion, iodine nutrition has a much closer association with female than male patients, and high iodine intake may be associated with CLNM and extrathyroidal extension in female PTMC patients.

High frequency of KRAS and EGFR mutation profiles in BRAF-negative thyroid carcinomas in Indonesia

OBJECTIVE

Thyroid cancer incidence has steadily increased in Indonesia. However, data on Kirsten rat sarcoma virus (KRAS) and EGFR mutations in thyroid cancer in Indonesia remain unavailable, except for BRAF-V600E, the most common BRAF gene mutation. This study aimed to analyze KRAS and EGFR mutation profiles in BRAF-V600E negative thyroid cancer samples.

RESULTS

BRAF-V600E mutations were found in papillary thyroid carcinomas in 40.3% patients with mean age of 53 years old. In BRAF-V600E-negative samples, 41.3% had KRAS mutations with mean age of 55.5 years old. KRAS mutation was found in 52.6% of follicular carcinomas and 47.4% of papillary thyroid carcinomas. Additionally, 45.7% had EGFR mutations in patients with mean age of 50.5 years old. EGFR mutation was found in 71.4% of papillary thyroid carcinoma and 28.6% of follicular carcinoma. Nearly half of the BRAF-V600E negative thyroid carcinoma samples harbored either KRAS or EGFR mutations. This finding suggests that in BRAF-V600E negative thyroid carcinoma samples, testing for RAS and EGFR mutation may be warranted for further therapeutic consideration.

Diagnostic value of multiple diagnostic methods for lymph node metastases of papillary thyroid carcinoma: A systematic review and meta-analysis

OBJECTIVE

This study compared the diagnostic value of various diagnostic methods for lymph node metastasis (LNM) of papillary thyroid carcinoma (PTC) through network meta-analysis.

METHODS

In this experiment, databases such as CNKI, Wanfang, PubMed, and Web of Science were retrieved according to the Cochrane database, Prisma, and NMAP command manual. A meta-analysis was performed using STATA 15.0, and the value of the surface under the cumulative ranking curve (SUCRA) was used to determine the most effective diagnostic method. Quality assessments were performed using the Cochrane Collaboration's risk of bias tool, and publication bias was assessed using Deeks' funnel plot.

RESULTS

A total of 38 articles with a total of 6285 patients were included. A total of 12 diagnostic methods were used to study patients with LNM of PTC. The results showed that 12 studies were direct comparisons and 8 studies were indirect comparisons. According to the comprehensive analysis of the area of SUCRA, US+CT(86.8) had the highest sensitivity, FNAC had the highest specificity (92.4) and true positive predictive value (89.4), and FNAC+FNA-Tg had higher negative predictive value (99.4) and accuracy (86.8). In the non-invasive method, US+CT had the highest sensitivity, and the sensitivity (SEN) was [OR=0.59, 95% confidence interval (CI): (0.30, 0.89]. Among the invasive methods, the combined application of FNAC+FNA-Tg had higher diagnostic performance. The sensitivity was [OR=0.62, 95% CI: (0.26, 0.98)], the specificity (SPE) was [OR=1.12, 95% CI: (0.59, 1.64)], the positive predictive value was [OR=0.98, 95% CI: (0.59, 1.37)], the negative predictive value was [OR=0.64, 95% CI (0.38, 0.90)], and the accuracy was [OR=0.71, 95% CI: (0.31, 1.12)].

CONCLUSION

In the non-invasive method, the combined application of US+CT had good diagnostic performance, and in the invasive method, the combined application of FNAC+FNA-Tg had high diagnostic performance, and the above two methods were recommended.

Nomograms for the prediction of lateral lymph node metastasis in papillary thyroid carcinoma: Stratification by size

Background

Lateral lymph node metastasis (LLNM) is a risk factor of poor prognosis in papillary thyroid cancer (PTC). We aimed to determine predictive factors and develop the nomograms for LLNM in patients with papillary thyroid microcarcinoma (PTMC) and macro-PTC.

Methods

We reviewed the medical records of 1,106 patients who underwent surgery between January 2019 and January 2022. Patients were divided into a PTMC and a macro-PTC group. We developed preoperative and postoperative nomograms for predicting LLNM based on results of multivariate analysis. Internal calibration was performed for these models.

Results

The number of metastatic lymph nodes in lateral compartment was higher in macro-PTC patients. LLNM was independently associated with gender, the number of foci, location, shape, and central lymph node metastasis (CLNM) in PTMC patients. For macro-PTC patients, chronic lymphocytic thyroiditis, the number of foci, location, margin, CLNM, and central lymph node ratio were all independent predictors for LLNM. All the above factors were incorporated into nomograms, which showed the perfect discriminative ability.

Conclusion

The diameter of the tumor has an impact on the rate of LLNM. Separate predictive systems should be used for PTMC and macro-PTC patients for more accurate clinical assessment of lateral lymph node status. Through these nomograms, we can not only detect high-risk patients with occult LLNM preoperatively, but also form appropriate treatment protocols for postoperative management of PTC patients with different risks.

Clinical and prognosis value of the number of metastatic lymph nodes in patients with papillary thyroid carcinoma

Objective

It has been reported that papillary thyroid carcinoma (PTC) patients with lymph node metastasis (LNM) are largely associated with adverse outcomes. The present study aimed to assess the correlation between the number of metastatic lymph nodes (NMLNs) and clinical prognosis in patients with PTC.

Methods

We retrospectively reviewed the medical records of patients with PTC who underwent initial thyroid cancer surgery in Renmin Hospital of Wuhan University between 2017 and 2019. A total of 694 patients with PTC and cervical lymph node dissection as well as a total checked number of lymph nodes ≥ 5 were involved in this study. The clinicopathological characteristics of patients were compared according to NMLNs, the number of central cervical lymph nodes (CLNs) and the number of lateral lymph nodes (LLNs).

Results

NMLNs > 5, CLNs > 5 and LLNs > 5 were 222 (32.0%), 159 (24.3%) and 70 (10.1%) seen in the analyzed samples, respectively. Young patients, patients with larger tumor diameter, bilaterality, multifocality and gross extrathyroidal extension (ETE) were more inclined to NMLNs > 5, CLNs > 5 and LLNs > 5 (P < 0.05). It was found that the recurrence-free survival among pN1 patients was significantly discrepant between different groups (NMLNs ≤ 5/5: P = 0.001; LLNs ≤ 5/5: P < 0.001). In multivariate logistic regression analysis, patients aged < 55 years (OR = 1.917), primary tumor size > 10 mm (OR = 2.131), bilaterality (OR = 1.889) and tumor gross ETE (OR = 2.759) were independent predictors for high prevalence of total NMLNs > 5 (P < 0.05). Specially, patients aged < 55 years (OR = 2.864), primary tumor size > 10 mm (OR = 2.006), and tumor gross ETE (OR = 2.520) were independent predictors for high prevalence of CLNs > 5 (P < 0.01); Bilaterality (OR = 2.119), CLNs > 5 (OR = 6.733) and tumor gross ETE (OR = 4.737) were independent predictors for high prevalence of LLNs > 5 (P < 0.05).

Conclusions

In conclusion, it is evident that NMLNs is related to the invasive clinicopathological features and adverse outcome of patients with PTC which should be correctly evaluated to provide an appropriate guidance for reasonable treatment and careful follow-up.

A novel tool for predicting the risk of central lymph node metastasis in patients with papillary thyroid microcarcinoma: a retrospective cohort study

Introduction

Central lymph node status in papillary thyroid microcarcinoma (PTMC) plays an important role in treatment decision-making clinically, however, it is not easy to predict central lymph node metastasis (CLNM). The present work focused on finding the more rational alternative for evaluating central lymph node status while identifying influencing factors to construct a model to predict CLNM incidence.

Methods

In this study, we retrospectively analyzed the typical sonographic and clinicopathologic features of 546 PTMC patients who underwent surgery, among which, the data of 382 patients were recruited in the training cohort and that of 164 patients in the validation cohort. Based on the outcome of the training cohort, significant influencing factors were further identified through univariate analysis and were considered as independent variables in multivariable logistic regression analysis and incorporated in and presented with a nomogram.

Results

In total, six independent predictors, including the age, sex, tumor size, multifocality, capsular invasion, Hashimotos thyroiditis were entered into the nomogram. Both internal validation and external validation revealed the favorable discrimination of our as-constructed nomogram. Calibration curves exhibited high consistency. As suggested by decision-curve analyses, the as-constructed nomogram might be applied in clinic. Besides, the model also distinguished patients according to risk stratification.

Conclusions

The novel nomogram containing remarkable influencing factors for CLNM cases was established in the present work. The nomogram can assist clinicians in clinical decision-making.

Single-Cell Transcriptome Analysis Reveals Inter-Tumor Heterogeneity in Bilateral Papillary Thyroid Carcinoma

Background

The tumor microenvironment (TME) plays a pivotal role in cancer progression in papillary thyroid carcinoma (PTC), yet the composition and the phenotype of cells within the TME in bilateral PTC are poorly understood.

Methods

We performed unbiased transcriptome-wide single-cell RNA sequencing (scRNA-seq) analysis on 29,561 cells from 3 pairs of bilateral PTC and 1 non-tumor thyroid sample. The results of the analysis were validated by a large-scale bulk transcriptomic dataset deposited in The Cancer Genome Atlas (TCGA) database.

Results

Our integrative analysis of thyroid follicular cells revealed 42 signaling pathways enriched in malignant follicular cells, including cytokine–cytokine receptor interaction, PI3K/Akt signaling pathway, mitogen-activated protein kinase (MAPK) signaling pathway, and tumor necrosis factor (TNF) signaling pathway. A 6-gene signature (CXCL3, CXCL1, IL1A, CCL5, TNFRSF12A, and IL18) in the cytokine–cytokine receptor interaction pathway was constructed to predict the prognosis of patients with PTC, with high risk scores being associated with decreased overall survival [hazard ratio (HR) = 3.863, 95% CI = 2.233−6.682, p < 0.001]. Gene set variation analysis (GSVA) indicated that the pathways enriched in bilateral PTC were significantly different, indicating great heterogeneity in bilateral PTC, even with the same BRAF V600E mutation. Comprehensive analysis of T cells revealed that the proportion of CD8⁺ tissue-resident memory T cells expressing IFNG decreased in tumor samples with advanced N stage. Within the myeloid compartment, the ratio of suppressive M2-like to pro-inflammatory M1-like macrophages increased with advanced disease stage, which was confirmed in the bulk dataset using transcriptomic profiles. In addition, we also identified numerous biologically critical interactions among myeloid cells, T cells, and follicular cells, which were related to T-cell recruitment, M2-like macrophage polarization, malignant follicular cell progression, and T-cell inhibitory signaling.

Conclusion

Our integrative analyses revealed great inter-tumor heterogeneity within the TME in bilateral PTC, which will offer assistance for precise diagnosis and treatment.

Preoperative Prediction of Central Cervical Lymph Node Metastasis in Fine-Needle Aspiration Reporting Suspicious Papillary Thyroid Cancer or Papillary Thyroid Cancer Without Lateral Neck Metastasis

Purpose

No non-invasive method can accurately determine the presence of central cervical lymph node (CCLN) metastasis in papillary thyroid cancer (PTC) until now. This study aimed to investigate factors significantly associated with CCLN metastasis and then develop a model to preoperatively predict CCLN metastasis in fine-needle aspiration (FNA) reporting suspicious papillary thyroid cancer (PTC) or PTC without lateral neck metastasis.

Patients and Methods

Consecutive inpatients who were diagnosed as suspicious PTC or PTC in FNA and underwent partial or total thyroidectomy and CCLN dissection between May 1^st, 2016 and June 30^th, 2018 were included. The total eligible patients were randomly divided into a training set and an internal validation set with the ratio of 7:3. Univariate analysis and multivariate analysis were conducted in the training set to investigate factors associated with CCLN metastasis. The predicting model was built with factors significantly correlated with CCLN metastasis and validated in the validation set.

Results

A total of 770 patients were eligible in this study. Among them, 268 patients had histologically confirmed CCLN metastasis, while the remaining patients did not. Factors including age, BRAF mutation, multifocality, size, and capsule involvement were found to be significantly correlated with the CCLN metastasis in univariate and multivariate analysis. A model used to predict the presence CCLN metastasis based on these factors and US CCLN status yielded AUC, sensitivity, specificity and accuracy of 0.933 (95%CI: 0.905-0.960, p < 0.001), 0.816, 0.966 and 0.914 in the training set and 0.967 (95%CI: 0.943-0.991, p < 0.001), 0.897, 0.959 and 0.936 in the internal validation set.

Conclusion

Age, BRAF mutation, multifocality, size, and capsule involvement were independent predictors of CCLN metastasis in FNA reporting suspicious PTC or PTC without lateral neck metastasis. A simple model was successfully built and showed excellent discrimination to distinguish patients with or without CCLN metastasis.

Clinicopathological Findings Associated With Cervical Lymph Node Metastasis in Papillary Thyroid Microcarcinoma: A Retrospective Study in China

Objective

The incidence of papillary thyroid microcarcinoma (PTMC) has increased sharply during the past decades. Yet, whether or not nodal dissection should be performed remains controversial. This article aims to assess the high-risk factors associated with cervical lymph node metastasis (LNM) in patients with PTMC, which may potentially guide clinical management decision-making.

Methods

Medical records of 449 PTMC patients who underwent thyroidectomy in our hospital from August 2016 to July 2017 were retrospectively reviewed. Clinical and pathological factors of the patients were anonymously extracted from the charts and analyzed.

Result

The patients were classified into two subgroups according to maximum tumor size measured through post-surgical pathology: smaller PTMC group (≤5 mm) and larger PTMC group (>5 mm). Larger tumor size was found to be associated with a higher rate of LNM (P = .001), particularly central lymph node metastasis (CLNM) (P = .001). Tumor size was also associated with extrathyroidal tumor extension (ETE) (P < .001), bilateral lesions (P = .015), and BRAF^v600e mutation (P = .004). LNM was found to be more common in older patients (>55 y) (P = .030), and those with multifocal cancer (P < .001). In PTMC patients with unilateral lesions without ETE, tumor size was not significantly associated with LNM (P = .121).

Conclusions

For the PTMC population, tumor size was an independent risk factor for LNM, particularly for patients of old age (>55 y), and multifocality. However, in PTMC patients with unilateral lesions without extrathyroidal extension, tumor size was not related to the risk of LNM. These findings may potentially guide clinical decision-making in terms of cervical nodal dissection.

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.

Washout DNA copy number analysis by low-coverage whole genome sequencing for assessment of thyroid FNAs

BACKGROUND

Papillary thyroid microcarcinoma (PTMC) is defined as a papillary carcinoma measuring ≤ 10 mm. The current management of PTMC has become more conservative; however, there are high-risk tumor features that can be revealed only postoperatively. For thyroid cancer, BRAF mutations and somatic copy number variation (CNV) are the most common genetic events. Molecular testing may contribute to clinical decision-making by molecular risk stratification, for example predicting lymph node (LN) metastasis. Here, we build a risk stratification model based on molecular profiling of thyroid fine needle aspiration (FNA) washout DNA (wDNA) for the differential diagnosis of thyroid nodules.

METHODS

Fifty-eight patients were recruited, FNA wDNA samples were analyzed using CNV profiling through low-coverage whole genome sequencing (LC-WGS) and BRAF mutation was analyzed using quantitative PCR. FNA pathology was reported as a Bethesda System for Reporting Thyroid Cytopathology (BSRTC) score. Ultrasound examination produced a Thyroid Imaging Reporting and Data System (TIRADS) score.

RESULTS

In total, 37 (63.8%) patients with a TIRADS score of 4A, 13 (22.4%) patients with a TIRADS score of 4B, and 8 (13.8%) patients with a TIRADS score of 4C were recruited after ultrasound examination. All patients underwent FNA with wDNA profiling. CNVs were identified in 17 (29.3%) patients. CNVs were frequent in patients with a BSRTC score of V or VI, including eight (47.1%) patients with a score of VI and five (29.4%) with a score of V, but not in patients with a score of III, II, or I (0%). BRAF mutation was not significantly correlated with BSRTC score. LN metastasis was found more frequently in CNV-positive (CNV+) than in CNV-negative (CNV-) patients (85.7% vs. 34.6%, odds ratio = 11.33, p = 0.002). In total, three molecular subtypes of thyroid nodules were identified in this study: 1) CNV+, 2) CNV- and BRAF positive (BRAF+), and 3) CNV- and BRAF negative (BRAF-). For the CNV+ subtype, 10 (83.3%) lesions with LN metastasis were found, including four (100%) small lesions (i.e. ≤ 5 mm). For the CNV- and BRAF+ nodules, LN metastases were detected in only seven (60.0%) larger tumors (i.e. > 5 mm). For CNV- and BRAF- tumors, LN metastasis was also frequently found in larger tumors only.

CONCLUSIONS

It is feasible to identify high-risk LN metastasis thyroid cancer from FNA washout samples preoperatively using wDNA CNV profiling using LC-WGS.

Expression Profiles of Circular RNAs in Human Papillary Thyroid Carcinoma Based on RNA Deep Sequencing

Background

Papillary thyroid carcinoma (PTC) is the most prevalent type of thyroid cancer. Herein, we purposed to explore the expression patterns of circRNAs in PTC with the overarching goal of improving early diagnosis rates for individuals with PTC.

Methods

We used RNA deep sequencing to determine the expression patterns of circRNAs in PTC. Besides, RT-qPCR was employed to confirm circRNAs. The diagnostic potential of the circRNAs was explored by constructing ROC curves. GO along with KEGG pathway analyses were utilized to elucidate the potential biological roles of differentially expressed circRNAs. Moreover, we predicted cross talks among circRNAs, miRNAs, and mRNAs, followed by establishment of a ceRNA network.

Results

Deep sequencing of four PTC pairs and neighboring nontumor tissues identified 16569 circRNAs, of which, 301 were upregulated and 419 were downregulated. The RT-qPCR data demonstrated that the expression of chr5: 38481299-38530666-, chr2: 159932176-159945082-, chr10: 179994-249088+, chr3: 121378716-121381532+, and chr1: 237423092-237445522+ was downregulated, while the expression of chr4: 25665378-25667298+, chr5: 161330883-161336769-, chr1: 12578718-12579412-, chr7: 116695750-116700284+, and chr7: 116699071-116700284+ was upregulated. The stability test exhibited that circRNAs were more tolerant to temperature, RNase R, and time. On the other hand, ROC curves illustrated that chr4: 25665378-25667298+, chr1: 12578718-12579412-, chr7: 116699071-116700284+, chr7: 116695750-116700284+, chr5: 161330883-161336769-, and chr10: 179994-249088+ were effective as diagnostic indicators. However, a logistic regression model combining the six indicators achieved a better combined prediction index, with 97.7% sensitivity and 95.3% specificity. Moreover, GO along with KEGG pathway analyses illustrated that differentially expressed circRNAs were linked to tumorigenesis. Furthermore, bioinformatics analyses established a promising ceRNAs network among mRNAs, circRNAs, and miRNAs.

Conclusion

Herein, we demonstrated that several circRNAs are promising PTC diagnostic biomarkers. Further study on the functions and mechanisms of these circRNAs may contribute to the understanding of PTC.

Magnetic nanoparticles for cancer theranostics: Advances and prospects

Cancer is one of the leading causes of mortality worldwide. Nanoparticles have been broadly studied and emerged as a novel approach in diagnosis and treatment of tumors. Over the last decade, researches have significantly improved magnetic nanoparticle (MNP)'s theranostic potential as nanomedicine for cancer. Newer MNPs have various advantages such as wider operating temperatures, smaller sizes, lower toxicity, simpler preparations and lower production costs. With a series of unique and superior physical and chemical properties, MNPs have great potential in medical applications. In particular, using MNPs as probes for medical imaging and carriers for targeted drug delivery systems. While MNPs are expected to be the future of cancer diagnosis and precision drug delivery, more research is still required to minimize their toxicity and improve their efficacy. An ideal MNP for clinical applications should be precisely engineered to be stable to act as tracers or deliver drugs to the targeted sites, release drug components only at the targeted sites and have minimal health risks. Our review aims to consolidate the recent improvements in MNPs for clinical applications as well as discuss the future research prospects and potential of MNPs in cancer theranostics.

Influence Factors for Lymph Node Metastasis in Papillary Thyroid Carcinoma: Hashimoto's Thyroiditis Has a Weak Effect on Central or Lateral Lymph Node Metastasis

Purpose

To analyze the effect of Hashimoto’s thyroiditis (HT) concurrent with papillary thyroid cancer (PTC) on cervical lymph node metastasis (LNM).

Methods

Two thousand nine hundred twenty-six patients who underwent thyroidectomy and lymph node dissection between January 2015 and December 2018 were enrolled in this study. Patient demographics and clinicopathologic features were analyzed.

Results

Of the total enrolled patients, 598 (20.4%) had concurrent HT. There were 1482 PTC cases with N0, 1033 cases with N1a, and 411 cases with N1b. Patients with HT had lower frequency of extrathyroidal extension (ETE), lymphatic vascular (LV) invasion, high pathological T stage (III+IV) and central LNM rate. Stratifying central LNM by non-ETE or without intrathyroidal spreading, it was further found that central LNM rate in patients with HT was lower than that of patients without HT. However, there was no significant difference in the central LNM rate in patients with PTC stratified by ETE or intrathyroidal spreading. HT with PTC played a weak protective role in N1a, reducing the risk of N1a by 16.4%. Conversely, HT is a risk factor for N1b, increasing the risk by 1.336 times compared to patients without HT. TgAb is an independent risk factor for N1b, which appears related to the promotion of N1b by HT.

Conclusion

In PTC, HT has a protective effect on central LNM and a risk effect on lateral LNM, although the difference was not significant. This weak protective effect on N1a is more obvious in PTC with less aggressive clinicopathologic characteristics. The risk effect of HT on N1b may be associated with TgAb.

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.

Risk Factors and Prediction Model for Lateral Lymph Node Metastasis of Papillary Thyroid Carcinoma in Children and Adolescents

Purpose

Papillary thyroid carcinoma (PTC) in children and adolescents is prone to lateral lymph node metastasis (LNM), which is a high-risk factor for recurrence. However, few studies focused on identifying risk factors and establishing prediction models for lateral LNM of PTC in children and adolescents.

Patients and Methods

We retrospectively reviewed consecutive cases of children and adolescents with PTC undergoing thyroidectomy and cervical lymph node dissection between January 2009 and December 2019. The demographics and clinicopathologic features were collected and analyzed.

Results

A total of 102 children and adolescents with PTC were enrolled in our study; 51 of whom had lateral LNM (50%). After adjusting for other risk factors, the independent risk factors for lateral LNM were multifocality (odds ratio [OR]: 6.04; 95% confidence interval [CI]: 1.653–22.092; p=0.007), tumor size (OR: 1.752; 95% CI: 1.043–2.945; p=0.034), and the number of central LNM (OR: 1.23; 95% CI: 1.028–1.472; p=0.023). The formula of the combined predictor is: Multifocality + 0.31 × Tumor size + 0.115 × Number of central LNM. The area under the receiver operating characteristic curve of multifocality, tumor size, number of central LNM, and the combined predictor was 0.706, 0.762, 0.748, and 0.855, respectively. When the value of the combined predictor was ≥2.2744, lateral LNM could be predicted. The sensitivity and specificity of the predicted value were 82.4% and 74.5%, respectively.

Conclusion

The independent risk factors for lateral LNM in children and adolescents with PTC were multifocality, tumor size, and the number of central LNM. The prediction model can better predict the presence of lateral LNM.

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.

The clinical importance of multifocality on tumor recurrence in papillary thyroid carcinoma

Background

Although the origin of the multifocality of papillary thyroid carcinoma (PTC) is unclear, it is not unusual and has not been considered as an independent prognostic factor from several tumor staging systems. This study aims to evaluate whether the presence of multifocality is associated with PTC recurrence.

Methods

We reviewed retrospectively detailed histological reports of PTC patients who underwent thyroidectomy from January 2000 through December 2010 at a single institution. We assessed the relationship between multifocality and other possible prognostic factors using binary logistic regression analysis. We compared recurrence by the Kaplan-Meier method (the log-rank test). We analyzed a prognostic factor for recurrence using Cox's proportional hazard model (the stepwise forward method).

Results

We enrolled a total of 434 PTC patients (380 women and 54 men; mean age, 48 years). The median follow-up period was 10.2 years. Of all PTC patients enrolled, 135 patients (31%) had multifocal PTC. There was a significant association between multifocality and cervical lymph node (CLN) metastasis (P=0.01). Multivariate analyses showed a significant association between multifocality and CLN metastasis (P<0.001). Multifocal PTC patients had higher CLN metastasis and tumor recurrence than those with single PTC. There was a significant association between multifocality and tumor recurrence (P=0.03 by log-rank test), but it disappeared in multivariate analysis.

Conclusions

Multifocality of PTC might be related to CLN metastasis and tumor recurrence.

Positive Thyroid Peroxidase Antibody and Thyroglobulin Antibody are Associated With Better Clinicopathologic Features of Papillary Thyroid Cancer

OBJECTIVE

To compare the thyroid autoantibody status of patients with papillary thyroid cancer (PTC) and benign nodular goiter as well as possible associations between thyroid autoantibodies and clinicopathologic features of PTC.

METHODS

A total of 3934 participants who underwent thyroidectomy were enrolled in this retrospective study. Patients were divided into PTC and benign nodule groups according to pathological diagnosis. Based on the preoperative serum antibody results, PTC patients were divided into thyroid peroxidase antibody (TPOAb)-positive, thyroglobulin antibody (TgAb)-positive, dual TPOAb- and TgAb-positive, or antibody-negative groups.

RESULTS

Of the 3934 enrolled patients, 2926 (74.4%) were diagnosed with PTC. Multivariate regression analyses suggested that high thyroid-stimulating hormone levels (adjusted odds ratio [OR] = 1.732, 95% CI [1.485-2.021], P < .001), positive TgAb (adjusted OR = 1.768, 95% CI [1.436-2.178], P < .001), and positive TPOAb (adjusted OR = 1.452, 95% CI [1.148-1.836], P = .002) were independent risk factors for predicting malignancy of thyroid nodules. Multinomial multiple logistic regression analyses indicated that positive TPOAb alone was an independent predictor of less central lymph node metastasis in PTC patients (adjusted OR = 0.643, 95% CI [0.448-0.923], P = .017), whereas positive TgAb alone was significantly associated with less extrathyroidal extension (adjusted OR = 0.778, 95% CI [0.622-0.974], P = .028). PTC patients with dual-positive TPOAb and TgAb displayed a decreased incidence of extrathyroidal extension (adjusted OR = 0.767, 95% CI [0.623-0.944], P = .012) and central lymph node metastasis (adjusted OR = 0.784, 95% CI [0.624-0.986], P = .037).

CONCLUSION

Although preoperative positive TPOAb and TgAb are independent predictive markers for PTC, they are also associated with better clinicopathologic features of PTC.

The Extent of Therapeutic Central Compartment Neck Dissection in Unilateral cT1N1a or cT2N1a Papillary Thyroid Carcinoma

Purpose

Papillary thyroid carcinomas (PTCs) frequently metastasize to the central neck compartment. Therapeutic central compartment neck dissection (CCND) is a well-established treatment for PTC nodal metastases; however, the extent to which therapeutic CCND should be performed remains controversial. In this study, we investigated the predictive risk factors for contralateral paratracheal lymph node metastasis (LNM) in unilateral cT1N1a or cT2N1a PTC.

Patients and Methods

In this case–control study, which was conducted at a single center, demographic and pathological data from unilateral cT1N1a or cT2N1a PTC patients were collected from January 2017 to March 2019. All patients were treated with total thyroidectomy and bilateral CCND.

Results

Two hundred thirty-seven patients met the inclusion criteria. Forty-nine patients (20.7%) were diagnosed with positive lymph nodes in the contralateral paratracheal region. Male sex (p=0.003), T2 disease (21–40 mm) (p<0.001), inferior pole tumor (p=0.011), near isthmus tumor (p<0.001), aggressive pathology (p<0.001), intraglandular dissemination (p=0.009), pretracheal LNM (p<0.001), >5 metastatic lymph nodes (p<0.001) and extranodal invasion (p=0.003) were significantly associated with contralateral paratracheal LNM in univariate analysis. Multivariate analysis showed that male sex (p=0.005, OR=17.545), T2 disease (p=0.003, OR=34.317), inferior pole tumor (p=0.022, OR=8.289), near isthmus tumor (p=0.001, OR=40.229), aggressive pathology (p=0.027, OR=48.063), pretracheal LNM (p=0.002, OR=14.235) and >5 metastatic lymph nodes (p=0.025, OR=23.426) were independent risk factors for contralateral paratracheal LNM.

Conclusion

Male sex, T2 disease, a tumor located near the isthmus or inferior pole, aggressive pathology, pretracheal LNM and >5 metastatic lymph nodes were predictive factors for contralateral paratracheal LNM in unilateral cT1N1a or cT2N1a PTC. These data may be useful to identify targets for surveillance or develop therapeutic interventions for patients with CCND.

High-risk factors for lymph node metastasis in contralateral central compartment in unilateral papillary thyroid carcinoma（cT1N0）

OBJECTIVE

The incidence of papillary thyroid carcinoma (PTC) increases yearly. Central lymph node metastasis (CLNM) is common in PTC. Many studies have addressed ipsilateral CLNM; however, few studies have evaluated contralateral CLNM. The purpose of this study is to investigate the high-risk factors of lymph node metastasis in the contralateral central compartment of cT1 stage in PTC.

METHODS

In total, 369 unilateral PTC (cT1N0) patients who underwent total-thyroidectomy with bilateral central lymph node dissection (CLND) between 2013 and 2016 in our hospital were retrospectively enrolled. Univariate and multivariate analyses identified the high-risk factors for contralateral CLNM of PTC.

RESULTS

The total metastasis rate of the ipsilateral central neck compartment was 31.71% (117/369). The total metastasis rate of the contralateral central neck compartment was 8.13% (30/369). The multivariate analysis showed that multifocality (p = 0.009), ipsilateral CLNM (p＜0.001), number of ipsilateral CLNM ＞2 (p = 0.006), tumor located at the inferior pole (p = 0.032) and tumor diameter ＞ 1 cm (p = 0.029) were independent risk factors for contralateral CLNM at cT1 stage in PTC, with odds ratios (ORs) of,4.132 (95% confidence intervals (CI): 1.430-11.936) ，8.591 (95% CI: 3.200-23.061) ，0.174 (95% CI: 0.050-0.601) ，0.353 (95% CI: 0.136-0.917)and 0.235 (95% CI: 0.064-0863), respectively.

CONCLUSION

The combinational use of these risk factors will help surgeons devise an appropriate surgical plan preoperatively. This information could provide reference for the readers who are interested and help to determine the optimal extent of CLND in patients with PTC, especially for cT1b patients.

Completion Total Thyroidectomy Is Not Necessary for Papillary Thyroid Microcarcinoma with Occult Central Lymph Node Metastasis: A Long-Term Serial Follow-Up

Simple Summary

The necessity of completion total thyroidectomy is unclear in patients with papillary thyroid microcarcinoma (PTMC) with only pathological central lymph node metastasis (pCLNM). The aim of our study was to determine the necessity of completion total thyroidectomy after an initial surgery by comparing the prognosis according to the presence of pCLNM during a long-term follow-up. We retrospectively compared the pathological central lymph node (pCLN)-positive group of 165 patients who underwent thyroid lobectomy with the pCLN-negative group of 711 patients and found no difference between the two groups in the recurrence rate and disease-free survival rates. Therefore, PTMC patients who underwent thyroid lobectomy with prophylactic central compartment neck dissection and were diagnosed with pCLNM after surgery do not require completion total thyroidectomy.

Abstract

The necessity of completion total thyroidectomy in patients with papillary thyroid microcarcinoma (PTMC) and pathological central lymph node metastasis (pCLNM) who underwent thyroid lobectomy with central compartment neck dissection (CCND) is unclear. We determined the necessity of completion total thyroidectomy by retrospectively comparing the prognosis according to the presence of pCLNM during a long-term follow-up. We enrolled 876 patients with PTMC who underwent thyroid lobectomy with prophylactic CCND from January 1986 to December 2009. Patients were divided according to central lymph node (CLN) metastasis: 165 (18.8%) and 711 (81.2%) in the CLN-positive and CLN-negative groups, respectively. Medical records were reviewed retrospectively, and clinicopathologic characteristics and recurrence rates were analyzed. The CLN-positive group was associated with male sex (p = 0.001), larger tumor size (p < 0.001), and more microscopic capsular invasion (p < 0.001) compared with the CLN-negative group. There was no significant difference between the two groups’ recurrence (p = 0.133) or disease-free (p = 0.065) survival rates. Univariate and multivariate analyses showed no factors associated with tumor recurrence except male sex (hazard ratio = 3.043, confidence interval 1.117–8.288, p = 0.030). Patients who were diagnosed with pCLNM after undergoing thyroid lobectomy with prophylactic CCND do not require completion total thyroidectomy; however, frequent follow-up is necessary for patients with PTMC and pCLNM.

Management of Lateral Multiple-Level Metastasis in N1b Papillary Thyroid Microcarcinoma

Background: The optimal extent of therapeutic lateral neck dissection (LND) in the management of N1b papillary thyroid microcarcinoma (PTMC) is still under debate in clinical practice. In this light, our study aims to explore the incidence, patterns, and predictive factors of the lateral multiple-level metastasis in N1b PTMC patients.

Methods: The clinical records of 142 patients diagnosed with N1b PTMC who underwent therapeutic LND from July 2015 to November 2018 at our institution were retrospectively reviewed. Univariate and multivariate analyses were conducted to examine the predictive factors associated with lateral multiple-level metastasis. The recurrence-free survival was analyzed and confirmed by Kaplan–Meier plots and log-rank test.

Results: The overall frequency of lateral multiple-level metastasis was 50.7% in N1b PTMC patients, and two-level to four-level simultaneous metastasis were present in 26.8, 17.6, and 6.3% patients, respectively. Extrathyroidal extension (ETE) (OR = 5.79, 95% CI, 1.36–24.59; P = 0.017) and the central metastatic lymph node ratio (CLNR) with values equal or higher than 0.61 (OR = 6.18, 95% CI, 2.53–15.09; P < 0.001) served as independent predictors of multiple-level metastasis in N1b PTMC patients. Moreover, locoregional recurrence was significantly higher in the selective neck dissection (SND) group compared to the modified radical neck dissection (MRND) one (HR = 3.65, 95% CI, 1.11–12.00; P = 0.03).

Conclusion: Our results show that the lateral multiple-level metastasis was relatively common, and we suggest MRND to be considered for N1b PTMC patients with ETE or CLNR equal or higher than 0.61.

Predictive Factors of Lymph Node Metastasis in Patients With Papillary Microcarcinoma of the Thyroid: Retrospective Analysis on 293 Cases

Introduction: Papillary thyroid microcarcinoma (PTMC) is defined as a tumor with a larger diameter ≤ 1 cm and is considered having an indolent course and an excellent prognosis. Nevertheless, the incidence of lymph node metastasis in PTMC is not negligible, reaching up to 65% in some series. The aim of this study was to assess the incidence of lymph node metastasis in patients with PTMC and to evaluate predictive factors for lymph node metastasis. Methods: We included in this retrospective observational study patients who underwent thyroidectomy with pathological diagnosis of PTMC at our department from January 2003 to June 2019. Results: Two hundred ninety-three patients were included in the study. The incidence of lymph node metastasis was 13.7%. Multivariate analysis revealed as independent risk factors for lymph node metastasis age <45 years, nodule size ≥6 mm, tall cell variant of PTC, extrathyroidal extension, and angioinvasion. Conversely, autoimmune thyroiditis was found as a protective factor for lymph node metastasis. A subgroup of patients, with nodule size ≤ 5 mm, presented non-aggressive features. Conclusion: The incidence of lymph node metastasis in PTMC is considerable; the size of the tumor appears to be the most significant predictive factor for lymph node metastasis. The traditional cut-off value used for definition of microcarcinoma could be reconsidered to identify patients with an indolent course of the tumor, where active surveillance could be the appropriate treatment, and on the other hand, patients with potentially aggressive tumors requiring an adequate surgical intervention. Clinical Trial Registration: The trial was registered at ClinicalTrials.gov (ID: NCT04274829).