Identifying risk factors of lateral lymph node recurrence in clinically node-negative papillary thyroid cancer

Association of Lymphovascular Invasion with Lymph Node Metastases in Prostate Cancer-Lateralization Concept

BACKGROUND

Lymphovascular invasion (LVI) is a vital but often overlooked prognostic factor in prostate cancer. As debates on lymphadenectomy's overtreatment emerge, understanding LVI laterality gains importance. This study pioneers the investigation into PCa, aiming to uncover patterns that could influence tailored surgical strategies in the future.

METHODS

Data from 96 patients with both LVI and lymph node invasion (LNI) were retrospectively analyzed. All participants underwent radical prostatectomy (RP) with modified-extended pelvic lymph node dissection (mePLND). All specimens underwent histopathological examination. The assessment of LVI was conducted separately for the right and left lobes of the prostate. Associations within subgroups were assessed using U-Mann-Whitney and Kruskal-Wallis tests, as well as Kendall's tau-b coefficient, yielding p-values and odds ratios (ORs).

RESULTS

Out of the 96 patients, 61 (63.5%) exhibited exclusive left-sided lymphovascular invasion (LVI), 24 (25.0%) had exclusive right-sided LVI, and 11 (11.5%) showed bilateral LVI. Regarding nodal involvement, 23 patients (24.0%) had LNI solely on the left, 25 (26.0%) exclusively on the right, and 48 (50.0%) on both sides. A significant correlation was observed between lateralized LVI and lateralized LNI (p < 0.001), particularly in patients with right-sided LVI only. LN-positive patients with left-sided LVI tended to have higher pT stages (p = 0.047) and increased odds ratios (OR) of bilateral LNI (OR = 2.795; 95% confidence interval [CI]: 1.231-6.348) compared to those with exclusive right-sided LVI (OR = 0.692; 95% CI: 0.525-0.913).

CONCLUSIONS

Unilateral LVI correlates with ipsilateral LNI in PCa patients with positive LNs, notably in cases of exclusively right-sided LVI. Left-sided LVI associates with higher pT stages and a higher percentage of bilateral LNI cases.

Transglutaminase 2 expression is associated with increased risk of lymph node metastasis and recurrence in papillary thyroid cancer

PURPOSE

Transglutaminase 2 (TG2) is associated with mobilization, invasion, and chemoresistance of tumor cells. We aimed to determine whether the immunohistochemical staining with TG2 antibody differs between metastatic and non-metastatic papillary thyroid cancer patients.

METHODS

We included 76 patients with papillary thyroid cancer (72% female, median age 52 (24-81) years, follow-up time 107 (60-216) months). Thirty of them with no metastasis, 30 of them with only lymph node metastasis and 16 patients with distant ± lymph node metastasis. Immunohistochemical staining of TG2 antibody was evaluated in the primary tumor and extra-tumoral tissue. We also divided subjects into two groups according to their primary tumor TG2 staining score (group A, high risk group: ≥3, n = 43; group B, low risk group: <3, n = 33).

RESULTS

Vascular invasion (p < 0.001), thyroid capsule invasion (p < 0.001), extrathyroidal extension (p < 0.001), intrathyroidal dissemination (p = 0.001), lymph node metastasis (p < 0.001), presence of aggressive histology (p < 0.001) were significantly higher in group A. No significant difference was found between the groups in terms of distant metastasis. Based on ATA risk classification 95.5% of patients with low risk were in group B but 86.8% of intermediate risk and 56.3% of high risk were in group A. In regression analysis, lymph node metastasis increased by 1.9 times with each one point increase in TG2 staining score.

CONCLUSION

TG2 staining score of the primary tumor may be a predictive factor for lymph node metastasis. High or low TG2 scores may effect the frequency of follow-up and decision of treatment regimens.

Lateral neck dissection for the treatment of synchronous and metachronous lateral neck metastasis of N1b papillary thyroid cancer

Introduction

Metachronous lateral neck recurrence after thyroidectomy for N1b papillary thyroid cancer is accompanied by high morbidity and increased difficulty of reoperation. From the perspective of recurrence, the objective of this study was to compare patients who underwent metachronous lateral neck dissection (mLND) despite initial thyroidectomy and patients who underwent synchronous lateral neck dissection (sLND) for papillary thyroid cancer and analyze the risk factors for recurrence after mLND.

Method

This retrospective study involved 1,760 patients who underwent lateral neck dissection for papillary thyroid cancer at the Gangnam Severance Hospital, a tertiary medical center in Korea, from June 2005 to December 2016. The primary outcome was structural recurrence, and secondary outcome measures were risk factors of recurrence in the mLND group.

Result

A total of 1,613 patients underwent thyroidectomy and sLND at diagnosis. In 147 patients, thyroidectomy alone was performed at the time of diagnosis, and mLND was performed when recurrence to the lateral neck lymph node was confirmed. During a median follow-up of 102.1 months, 110 (6.3%) patients experienced a recurrence. There was no significant difference in the recurrence between the sLND and mLND groups (6.1% vs 8.2%, P=.32). The period from lateral neck dissection to recurrence was longer in the mLND group than in the sLND group (113.6 ± 39.4 months vs 87.0 ± 33.8 months, respectively, P<.001). Age ≥50 years (adjusted HR=5.209, 95% CI=1.359-19.964; P=.02), tumor size >1.45 cm (adjusted HR=4.022, 95% CI=1.036-15.611; P=.04), and lymph node ratio in the lateral compartment (adjusted HR=4.043, 95% CI=1.079-15.148; P=.04) were independent variables predictive of recurrence after mLND.

Conclusion

mLND is suitable for treating lateral neck recurrence in patients with N1b papillary thyroid cancer who previously underwent thyroidectomy. Lateral neck recurrence after treatment in patients who underwent mLND was predicted by age, tumor size, and lymph node ratio in the lateral compartment.

The risk of central nodal metastasis based on prognostic factors of the differentiated thyroid carcinoma: a systematic review and meta-analysis study

BACKGROUND AND AIM

Despite improving the 10-year disease-free-survival, prophylactic central neck dissection (pCND) in differentiated thyroid carcinoma (DTC) should only be considered in patients with high risk factors for lymph node (LN) metastasis due to the increases in the risk of postoperative complications. Our aim was to identify the risk factors for central lymph node metastasis (CLNM) in DTC.

METHOD

We searched PubMed, Scopus, Web of science, Cochrane library for eligible studies from inception to November 1, 2021 and a systematic review and meta-analysis were carried out to identify the risk factors for CLNM in DTC.

RESULTS

We included 41 studies with total of 27,741 patients in this study. The pooled results in this meta-analysis showed that these risk factors were significantly associated with CLNM: age < 45 years (odds ratio (OR) 1.64, 95% confidence interval (CI) 1.34-1.99, p < 0.00001), male sex (OR 1.73, 95% CI 1.54-1.93, p < 0.00001), multifocality (OR 1.87, 95% CI 1.59-2.19, p < 0.00001), bilateral disease (OR 1.43, 95% CI 1.15-1.78, p < 0.001), capsular invasion (OR 1.67, 95% CI 1.10-2.54, p < 0.02), lymphovascular invasion (OR 4.89, 95% CI 2.76-8.66, p < 0.00001) and extra-thyroidal extension (OR 2.43, 95% CI 1.97-3.00, p < 0.00001). In addition, young age (< 45 years), male sex, multifocality, and extra-thyroidal extension were significantly associated with large-volume CLNM in clinically N0 DTC patients. However, the presence of Hashimoto's thyroiditis was not a predictors of large-volume CLNM.

CONCLUSION

Young age (< 45 years), male sex, bilateral disease, multifocality, capsular invasion, lymphovascular invasion and extra-thyroidal extension are significantly associated with CLNM and pCND would be expected to have a higher yield in patients with these risk factors.

Risk stratification of lateral neck recurrence for patients with pN1a papillary thyroid cancer

BACKGROUND

Lateral neck is not recommended for dissection in patients with pN1a papillary thyroid cancer (PTC), but its recurrence risk has not been well stratified. We aimed to develop a risk stratification system for lateral neck recurrence in patients with pN1a PTC.

METHODS

Patients with pN1a PTC who underwent thyroidectomy and unilateral central compartment dissection from 2000-2016 were enrolled. The association between number of central lymph node metastases (CLNMs) and lateral neck recurrence was comprehensively assessed using a Cox proportional hazards model with restricted cubic spline. Stratification was then performed based on CLNMs and other significant risk factors selected by multivariate analysis. Lateral neck recurrent-free survival (LRFS) rate of each stratification was estimated with Kaplan-Meier curve and comparison was performed using log-rank test.

RESULTS

Ninety-six (3.8%) lateral neck recurrences were identified during a median follow-up of 62 months among a total of 2500 admitted cases. An increasing number of CLNMs was associated with compromised LRFS for up to 6 CLNMs (P < 0.001), and CLNMs > 3 indicated significantly worse 5-year LRFS than that of CLNM ≤ 3 (90.6% vs. 98.1%, P < 0.001). When stratification with CLNMs and primary tumor size (selected by multivariate analysis, HR (95%CI) = 4.225(2.460-7.256), P < 0.001), 5-year LRFS rates of high- (CLNMs > 3 and primary tumor size > 2 cm), intermediate- (CLNMs > 3 and primary tumor size 1-2 cm) and low-risk (primary tumor size ≤ 1 cm or CLNMs ≤ 3) groups were 78.5%, 90.0% and 97.9%, respectively (P < 0.05).

CONCLUSIONS

The number of CLNMs combined with primary tumor size seems to effectively stratify lateral neck recurrence risk for patients with pN1a PTC.

Magnetic resonance imaging (MRI) radiomics of papillary thyroid cancer (PTC): a comparison of predictive performance of multiple classifiers modeling to identify cervical lymph node metastases before surgery

PURPOSE

To compare predictive efficiency of multiple classifiers modeling and establish a combined magnetic resonance imaging (MRI) radiomics model for identifying lymph node (LN) metastases of papillary thyroid cancer (PTC) preoperatively.

MATERIALS AND METHODS

A retrospective analysis based on the preoperative MRI scans of 109 PTC patients including 77 patients with LN metastases and 32 patients without metastases was conducted, and we divided enroll cases into trained group and validation group. Radiomics signatures were selected from fat-suppressed T2-weighted MRI images, and the optimal characteristics were confirmed by spearman correlation test, hypothesis testing and random forest methods, and then, eight predictive models were constructed by eight classifiers. The receiver operating characteristic (ROC) curves analysis were performed to demonstrate the effectiveness of the models.

RESULTS

The area under the curve (AUC) of ROC based on MRI texture diagnosed LN status by naked eye was 0.739 (sensitivity = 0.571, specificity = 0.906). Based on the 5 optimal signatures, the best AUC of MRI radiomics model by logistics regression classifier had a considerable prediction performance with AUCs 0.805 in trained group and 0.760 in validation group, respectively, and a combination of best radiomics model with visual diagnosis of MRI texture had a high AUC as 0.969 (sensitivity = 0.938, specificity = 1.000), suggesting combined model had a preferable diagnostic efficiency in evaluating LN metastases of PTC.

CONCLUSION

Our combined radiomics model with visual diagnosis could be a potentially effective strategy to preoperatively predict LN metastases in PTC patients before clinical intervention.

A Set of Markers Related to Viral Infection Has a Sex-sensitive Prognostic Value in Papillary Thyroid Carcinoma

CONTEXT

Although the incidence of papillary thyroid carcinoma (PTC) is significantly higher in females than in males, the prognosis of male PTC is more unfavorable. However, the cause of higher malignancy of PTC in male patients remains unclear.

OBJECTIVE

We conducted our analysis on microarrays datasets, tissue samples from PTC patients and the RNAseq datasets from TCGA with survival data.

METHODS

We searched all publicly available microarray datasets and performed a genome-wide meta-analysis comparing PTC and normal samples. Gene Ontology analysis was then conducted. The candidate genes were tested by quantitative real-time polymerase chain reaction. The analysis of prognostic value of genes was performed with datasets from The Cancer Genome Atlas.

RESULTS

After meta-analyses, 150 significantly differentially expressed genes (DEGs) were specifically found in male subjects. Gene Ontology analysis of these 150 genes revealed that the viral process was activated. Seven genes involved in the viral process in male patients showed a significantly differential expression between PTC and normal tissue. Survival analysis exhibited that the 7 genes, used in combination, were prognostically valuable and, of them, PSMB1 possessed a conspicuous prognostic value, especially in males.

CONCLUSION

In this study, we searched all publicly available microarray datasets and conducted a comprehensive analysis to understand the male propensity for higher malignancy. We found that markers of viral infection showed significantly differential expression only in male patients compared with their female counterparts and had a sex-sensitive prognostic value in PTC.

Application of Carbon Nanoparticles in Neck Dissection of Clinically Node-Negative Papillary Thyroid Carcinoma

Purpose

The purpose of this retrospective study was to evaluate the advantages of carbon nanoparticles in neck dissection and to conclude its application in the treatment of clinically node-negative papillary thyroid carcinoma (CN0PTC).

Methods

As a retrospective cohort study, we divided the enrolled patients into two groups, the carbon nanoparticle (CN) group and the control group according to the usage of CN. In the CN group, CN was applied to reveal drainage lymph nodes and the picked LNs were sent for fast frozen testing. If metastasis exits, modified radical lateral lymph node dissection (LLND) was performed. For both groups, prophylactic central lymph node dissection was routinely done. Finally, the demographic information, tumor characteristics, postoperative pathological results, and laboratory data were collected for analysis.

Results

A total of 61 CN0PTC were enrolled in this study, 33 in the CN group and 28 in the control group. The black-stained rate for CN was 29/40 (72.5%) with a positive prediction rate of 34.5%. The mainly black-stained region in the lateral neck was level III and possesses the highest lymph node ratio (17.5%). The metastasis that occurred in level VI was 30% and 11.8% in the CN and control groups, respectively (p = 0.058). During the available follow-up, no one showed recurrence. Statistical analysis showed that the CN suspension can significantly reduce the risk of damage to the parathyroid gland (p = 0.001 for hypocalcemia, <0.05; p = 0.047 for hypoparathyroidism, <0.05).

Conclusion

The lateral neck metastasis in patients with papillary thyroid microcarcinoma in clinical stage cT1aN0 is not rare. CN can help surgeons to distinguish the real person who actually needs LLND. In prophylactic CLND, CN acts as a tracer which makes the parathyroid gland more identifiable and avoids risks of injuries to nerves and glands.

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.

MRI-based radiomics analysis to predict preoperative lymph node metastasis in papillary thyroid carcinoma

Background

The aim of the present study was to develop a magnetic resonance imaging (MRI) radiomics model and evaluate its clinical value in predicting preoperative lymph node metastasis (LNM) in patients with papillary thyroid carcinoma (PTC).

Methods

Data of 129 patients with histopathologically confirmed PTC were retrospectively reviewed in our study (90 in training group and 39 in testing group). 395 radiomics features were extracted from T2 weighted imaging (T2WI), diffusion weighted imaging (DWI) and T1 weighted multiphase contrast enhancement imaging (T1C+) respectively. Minimum redundancy maximum relevance (mRMR) was used to eliminate irrelevant and redundant features and least absolute shrinkage and selection operator (LASSO), to additionally select an optimized features' subset to construct the radiomics signature. Predictive performance was validated using receiver operating characteristic curve (ROC) analysis, while decision curve analyses (DCA) were conducted to evaluate the clinical worth of the four models according to different sequences. A radiomics nomogram was built using multivariate logistic regression model. The nomogram's performance was assessed and validated in the training and validation cohorts, respectively.

Results

Seven key features were selected from T2WI, five from DWI, ten from T1C+ and seven from the combined images. The scores (Rad-scores) of patients with LNM were significantly higher than patients with non-LNM in both the training cohort and the validation cohort. The combined model performed better than the T2WI, DWI, and T1C+ models alone in both cohorts. In the training cohort, the area under the ROC (AUC) values of T2WI, DWI, T1C+ and combined features were 0.819, 0.826, 0.808, and 0.835, respectively; corresponding values in the validation cohort were 0.798, 0.798, 0.789, and 0.830. The clinical utility of the combined model was confirmed using the radiomics nomogram and DCA.

Conclusions

MRI radiomic model based on anatomical and functional MRI images could be used as a non-invasive biomarker to identify PTC patients at high risk of LNM, which could help to develop individualized treatment strategies in clinical practice.

Prophylactic lymph node dissection in clinically N0 differentiated thyroid carcinoma: example of personalized treatment

Considering the 'differentiated thyroid carcinoma (DTC) epidemic', the indolent nature of DTC imposes a treatment paradigm shift toward elimination of recurrence. Lymph node metastases in cervical compartments, encountered in 20-90% of DTC, are the main culprit of recurrent disease, affecting 5-30% of patients. Personalized risk-stratified cervical prophylactic lymph node dissection (PLND) at initial thyroidectomy in DTC with no clinical, sonographic or intraoperative evidence of lymph node metastases (clinically N0) has been advocated, though not unanimously. The present review dissects the controversy over PLND. Weighing the benefit yielded from PLND up against the PLND-related morbidity is so far hampered by the inconsistent profit yielded by PLND and the challenging patient selection. Advances in tailoring PLND are anticipated to empower optimal patient care.

Total Thyroidectomy with Central Node Dissection is a Valuable Option in Papillary Thyroid Cancer Treatment

Introduction

Papillary thyroid cancer is one of the cancers with favorable prognosis, although the long-term recurrence rate in the paratracheal region is reported to be as high as 30%. The use of ¹³¹I is considered to be a reliable treatment option for lymph node metastases in the paratracheal region. According to the majority of internationally accepted guidelines, it is not recommended to perform central node dissection (CND) routinely. Total thyroidectomy (TT) remains an adequate treatment for these patients. According to many studies, CND is associated with higher rates of hypoparathyroidism. However, CND improves staging.

Methods

We performed a retrospective study. We included 248 patients treated for papillary thyroid cancer during a 20-year period. Data were collected on patient (age, sex) and tumor (size, focality) characteristics, presence of metastases in the central neck compartment, incidence of postoperative hypoparathyroidism, and locoregional failure. We divided patients into two groups based on pathological analysis: those without positive lymph nodes (N0) and those with positive paratracheal lymph nodes (N1). We compared patient and tumor characteristics and risk of recurrence between the two groups. Results: There were 39.5% patients with central neck metastases in our series. In the central neck dissection specimen, 5.5 nodes were found on average. Hypoparathyroidism was found in 23.4% of patients and remained permanent in 3.2% of patients. Female and older patients had a lower chance of central compartment metastases, as did patients with smaller and unifocal tumors. Recurrence risk was doubled for the N1 group. All tested differences between the groups reached statistical significance.

Discussion and conclusion

In our hands, CND was a safe and effective surgical procedure. It improved staging and postsurgical management. Efforts should be made to improve the preoperative work-up in order to more accurately identify high-risk patients.

The effectiveness of prophylactic ipsilateral central neck dissection in selected patients who underwent total thyroidectomy for clinically node-negative unilateral papillary thyroid carcinoma

Background

Prophylactic central neck dissection (CND) in clinically node-negative (cN0) papillary thyroid carcinoma (PTC) remains controversial. The purpose of this study was to evaluate the benefits of prophylactic ipsilateral CND compared with bilateral CND in total thyroidectomy for cN0 unilateral PTC.

Methods

We retrospectively enrolled 174 patients who underwent total thyroidectomies with prophylactic CND for cN0 unilateral PTC between January 2009 and May 2010. The prophylactic CND patients were divided into group 1, the ipsilateral CND group (n=74), and group 2, the bilateral CND group (n=100). The incidence of central lymph node metastasis (CLNM) and postoperative complications, such as hypoparathyroidism, recurrent laryngeal nerve injury, and recurrence were assessed.

Results

CLNM was found in 22 (29.8%) in group 1 and 69 (69%) in group 2. The incidence of postoperative severe hypocalcemia less than 7.0 was also significantly different (six patients [8.1%] in group 1 and 23 [23%] in group 2; p=0.009). Permanent hypoparathyroidism was significantly more frequent in group 2 (4.1% vs. 19%; p=0.005). However, the incidence of transient hypoparathyroidism, recurrence, and recurrent laryngeal nerve injury was not significantly different.

Conclusion

Prophylactic ipsilateral CND has advantage not only to reduce incidence of some complications but also to have similar recurrence rate compared with bilateral CND. We suggest that prophylactic ipsilateral CND may be safe and effective for selected patients undergoing total thyroidectomy for cN0 unilateral PTC.