Iodine-131: An Effective Method for Treating Lymph Node Metastases of Differentiated Thyroid Cancer

Exploration and validation of key genes associated with early lymph node metastasis in thyroid carcinoma using weighted gene co-expression network analysis and machine learning

Background

Thyroid carcinoma (THCA), the most common endocrine neoplasm, typically exhibits an indolent behavior. However, in some instances, lymph node metastasis (LNM) may occur in the early stages, with the underlying mechanisms not yet fully understood.

Materials and methods

LNM potential was defined as the tumor's capability to metastasize to lymph nodes at an early stage, even when the tumor volume is small. We performed differential expression analysis using the 'Limma' R package and conducted enrichment analyses using the Metascape tool. Co-expression networks were established using the 'WGCNA' R package, with the soft threshold power determined by the 'pickSoftThreshold' algorithm. For unsupervised clustering, we utilized the 'ConsensusCluster Plus' R package. To determine the topological features and degree centralities of each node (protein) within the Protein-Protein Interaction (PPI) network, we used the CytoNCA plugin integrated with the Cytoscape tool. Immune cell infiltration was assessed using the Immune Cell Abundance Identifier (ImmuCellAI) database. We applied the Least Absolute Shrinkage and Selection Operator (LASSO), Support Vector Machine (SVM), and Random Forest (RF) algorithms individually, with the 'glmnet,' 'e1071,' and 'randomForest' R packages, respectively. Ridge regression was performed using the 'oncoPredict' algorithm, and all the predictions were based on data from the Genomics of Drug Sensitivity in Cancer (GDSC) database. To ascertain the protein expression levels and subcellular localization of genes, we consulted the Human Protein Atlas (HPA) database. Molecular docking was carried out using the mcule 1-click Docking server online. Experimental validation of gene and protein expression levels was conducted through Real-Time Quantitative PCR (RT-qPCR) and immunohistochemistry (IHC) assays.

Results

Through WGCNA and PPI network analysis, we identified twelve hub genes as the most relevant to LNM potential from these two modules. These 12 hub genes displayed differential expression in THCA and exhibited significant correlations with the downregulation of neutrophil infiltration, as well as the upregulation of dendritic cell and macrophage infiltration, along with activation of the EMT pathway in THCA. We propose a novel molecular classification approach and provide an online web-based nomogram for evaluating the LNM potential of THCA (http://www.empowerstats.net/pmodel/?m=17617_LNM). Machine learning algorithms have identified ERBB3 as the most critical gene associated with LNM potential in THCA. ERBB3 exhibits high expression in patients with THCA who have experienced LNM or have advanced-stage disease. The differential methylation levels partially explain this differential expression of ERBB3. ROC analysis has identified ERBB3 as a diagnostic marker for THCA (AUC=0.89), THCA with high LNM potential (AUC=0.75), and lymph nodes with tumor metastasis (AUC=0.86). We have presented a comprehensive review of endocrine disruptor chemical (EDC) exposures, environmental toxins, and pharmacological agents that may potentially impact LNM potential. Molecular docking revealed a docking score of -10.1 kcal/mol for Lapatinib and ERBB3, indicating a strong binding affinity.

Conclusion

In conclusion, our study, utilizing bioinformatics analysis techniques, identified gene modules and hub genes influencing LNM potential in THCA patients. ERBB3 was identified as a key gene with therapeutic implications. We have also developed a novel molecular classification approach and a user-friendly web-based nomogram tool for assessing LNM potential. These findings pave the way for investigations into the mechanisms underlying differences in LNM potential and provide guidance for personalized clinical treatment plans.

Do radioiodine-avid lymph nodes from differentiated thyroid cancer on the initial posttherapy scan need repeated 131I therapy?

Background

Residual/recurrent lymph node metastase (LNM) is often found after differentiated thyroid cancer (DTC) surgery. This study aimed to investigate whether patients complicated with radioiodine-avid (131I+) lymph nodes from DTC on the initial posttherapy scan (PTS) need repeated 131I therapy.

Methods

From June 2013 to August 2022, DTC patients with 131I+ lymph nodes on the initial PTS who received at least two cycles of 131I therapy were retrospectively enrolled. They were divided into a complete response (CR) group and an incomplete response (IR) group according to their response to the initial 131I therapy based on the 2015 American Thyroid Association (ATA) guidelines.

Results

A total of 170 DTC patients with 131I+ lymph nodes on the initial PTS were included; 42/170 (24.7%) patients were classified into the CR group and 128/170 (75.9%) were classified into the IR group according to their response to the initial 131I therapy. None of the 42 CR patients had disease progression at the subsequent follow-up, and 37/170 (21.8%) IR patients improved after repeated therapy. Univariate analysis showed that N stage (P=0.002), stimulated thyroglobulin (sTg) level before initial 131I therapy (P<0.001), LNM size (P<0.001), number of total residual/recurrent LNM (P=0.021), radioiodine-nonavid (131I-) LNM (P=0.002) and ultrasound features (P<0.001) were related to the initial treatment response. On multivariate analysis, sTg level (OR=1.186, P<0.001) and LNM size (OR=1.533, P=0.004) were independent risk factors for IR after initial 131I therapy. The optimal sTg level and LNM size cutoff value for predicting the treatment response after initial 131I therapy were 18.2 µg/l and 5mm.

Conclusion

This study suggested that approximately one-quarter of patients with 131I+ lymph nodes on initial PTS, especially those with N0 or N1a stage, lower sTg level, smaller LNM size, ≤2 residual/recurrent LNMs, negative ultrasound features and no 131I- LNM, remain stable after one cycle of 131I therapy and do not need repeated therapy.

Clinical outcomes of a conservative approach in cervical lymph node metastases of thyroid cancer

CONTEXT

Lymph node metastases (LNM) can be present in 35% of patients with differentiated thyroid cancer (DTC), and the management of persistent/recurrent nodal disease has been controversial. Watchful waiting may be a reasonable approach in selected patients, but uncertainty about clinical outcomes remains a concern.

OBJECTIVE

To investigate the outcomes of patients with DTC with recurrent/persistent confirmed LNM under surveillance.

METHODS

Patients with LNM from DTC were selected from databases of needle washout thyroglobulin measurements and fine-needle aspiration biopsies performed in our institution. Patients with confirmed metastases, in whom active surveillance was initially proposed, were selected. Main clinical outcomes were analysed.

RESULTS

We found 89 patients with LNM under surveillance. Classic papillary was the most frequent variant (44%). During a median follow-up of 3 (0.5-17.2) years, different treatments were needed in 35 (39.3%) patients: radioactive iodine (RAI) in 23 (25.8%), surgery in 9 (10.1%) and radiotherapy (RT) in 3 (3.4%). From those submitted initially to RAI, progression of disease was observed in 8 patients, 4 requiring other treatment modalities: surgery (n = 2), RT (n = 1) and RAI (n = 1). The remaining 54 (60.7%) patients maintained surveillance. In this group, progression of disease was observed in 26 (48.1%), due to increase in the number and/or volume of metastases, but further treatments were not required.

CONCLUSION

In a group of patients with cervical LNM under active surveillance, only 16.9% (n = 15) required invasive intervention (surgery or RT).

Predictive Value of Thyroglobulin Changes for the Curative Effect of Radioiodine Therapy in Patients With Metastatic Differentiated Thyroid Carcinoma

BACKGROUND

Serum thyroglobulin (Tg) serves as a sensitive and easily available tumor marker for patients with metastatic differentiated thyroid carcinoma (m-DTC). The aim of the present study was to evaluate the predictive value of suppressed Tg changes (Δsup-Tg) and/or stimulated Tg changes (Δsti-Tg) to evaluate the efficacy of radioiodine therapy (RT).

METHODS

We studied 117 patients with m-DTC who received RT. Δsup-Tg and Δsti-Tg were compared after the first RT in different therapeutic response groups and a receiver-operating characteristic (ROC) curve was used to determine the cut-off values to predict non-remission. Univariate and multivariate analyses were used to investigate the effects of 17 observed factors on the efficacy of RT.

RESULTS

A total of 218 RT events in 117 patients with m-DTC were analyzed. After the last RT, the remission rate was 70.94% (83/117), and the proportion of remission events accounted for 74.77% (163/218). ROC curve analysis showed that the cut-off values for Δsup-Tg and Δsti-Tg after the first RT to predict the non-remission of RT were 21.54% and 27.63%, respectively. Age, the size of the metastasis, the maximum count of target metastatic lesions and the average count of contralateral non-target tissue on tomographic imaging (T_max/NT_mean) of the first RT, and Δsup-Tg after the first RT were identified as independent factors associated with RT efficacy.

CONCLUSIONS

Tg response was valuable to predict RT efficacy for patients with m-DTC. Age, the size of the metastasis, T_max/NT_mean, and Δsup-Tg after the first RT were verified as independent predictive factors of RT efficacy.

Unilateral Tnm T1 And T2 Papillary Thyroid Carcinoma With Lateral Cervical Lymph Node Metastasis: Total Thyroidectomy or Lobectomy?

OBJECTIVE

The aim of this study was to explore the effect of total thyroidectomy (TT) and lobectomy (LT) on the prognosis of unilateral papillary thyroid carcinoma (PTC) with lateral cervical lymph node metastasis.

METHODS

Patients with PTC and lateral cervical lymph node metastasis who underwent lateral cervical lymph node dissection between January 2007 and December 2016 were retrospectively reviewed. To investigate the effect of surgical procedure on the prognosis of lymph node metastasis patients, other high-risk factors such as extrathyroidal invasion and large tumor size were excluded. All patients were in Tumor-Node-Metastasis (TNM) stage T1 and T2. Primary end point was recurrence-free survival (RFS).

RESULTS

Among 264 PTC patients, 104 (39.4%) patients received TT and 160 (60.6%) patients received LT. With a median follow-up of 50 months (interquartile range, 34 to 74 months), 7 patients (2.65%) experienced recurrence. The 5-year RFS in the TT and LT groups was 96.1% and 97.7%, respectively, and was not significantly different (P = .765). Similar results were found when excluding patients who received radioiodine ablation, which were 97.7% and 97.4%, respectively (P = .752). Age ≥55 years (hazard ratio, 7.368; P = .018) and multifocality in the ispi-lateral lobe (hazard ratio, 10.059; P =.006) were identified as independent risk factors of recurrence.

CONCLUSION

For unilateral TNM T1 and T2 PTC patients with lateral lymph node metastasis, there was no significant difference in the effect of TT and LT for RFS in the absence of other risk factors during the follow-up period. Patient age ≥55 years with multifocality in the unilateral lobe might be independent risk factors for prognosis.

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 BRAF V600E mutation is a predictor of the effect of radioiodine therapy in papillary thyroid cancer

Objective: To investigate the correlation between the BRAF V600E gene mutation and clinicopathological features and thyroid function after iodine-131 treatment in patients with papillary thyroid cancer (PTC). Methods: A total of 128 PTC patients who underwent iodine-131 treatment after a total thyroidectomy from February 2015 to November 2016 at Hunan Cancer Hospital, China, were recruited. There were 25 males and 103 females. The age range was 11 to 73 years old. The BRAF V600E mutation in tumor tissues was detected by amplification-restriction mutation system polymerase chain reaction (ARMS-PCR), and the serum levels of Tg, TSH, Tg-Ab, and Tpo-Ab were measured by chemiluminescence after iodine-131 treatment. The BRAF V600E mutation was shown to be associated with clinicopathological characteristics and thyroid function indicators after iodine-131 treatment. Results: BRAF V600E mutation was detected in 75 of the 128 patients (58.6%) and was observed more frequently in cases with elevated Tg levels (Tg>1.00) at 3, 6, 12, and 18 months after treatment compared with patients without any BRAF mutations (P<0.05). Patients with BRAF V600E mutation had significant lower level of Tg-Ab at 3 and 12 months after treatment with iodine-131 than patients without BRAF V600E mutation (P<0.05). Among the 75 BRAF V600E patients, no significant association was found between the levels of TSH and Tpo-Ab after iodine-131 treatment (P>0.05). The BRAF V600E mutation was closely associated with the high-risk and age of the patient (≥45 years old) (P<0.05), but there was no significant correlation with gender, clinical stage, and distant metastasis. Conclusion: The BRAF V600E mutation is closely related to serum Tg elevation after treatment with iodine-131 in papillary thyroid cancer. These findings suggest that this BRAF mutation may be a predictor of the efficacy of iodine-131 treatment for papillary thyroid cancer.

Predictive value of LN metastasis detected by 18F-FDG PET/CT in patients with papillary thyroid cancer receiving iodine-131 radiotherapy

The aim of the present study was to predict the prognostic value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the metastatic lymph nodes (mLNs) of patients with papillary thyroid carcinoma (PTC) with a negative iodine-131 (¹³¹I) whole-body scan (WBS). The present retrospective study included 32 patients with PTC undergoing standard surgery and radioiodine treatment. All patients received ¹⁸F-FDG PET/CT imaging prior to and following therapy. All mLNs were divided into an effective treatment group (group A) and ineffective treatment group (group B) based on the PET Response Criteria in Solid Tumors 1.0 guidelines. All the patients were followed up for ≥9 months. A significant difference was identified in the peak standardized uptake value (SULpeak) between group B (7.85±3.20) and group A (5.36±2.19). A cut-off value of 5.85 was used to distinguish ineffective treatment of lesions from mLNs receiving radioactive ablation based on receiver operating characteristic (ROC) curve analysis with an area under the ROC curve of 0.755. Patients with a high SULpeak (P=0.003) and extrathyroidal extension (P=0.030), confirmed by pathology, more frequently exhibited a poor prognosis. In conclusion, tracer uptake of ¹⁸F-FDG for cervical metastatic nodes was revealed as a predictor for the clinical outcome of patients with PTC treated with radioiodine therapy. The present results also indicated that high SULpeak and extrathyroidal extension are poor predictors for patients with mLNs receiving ¹³¹I therapy.

Usefulness of Stereotactic Radiotherapy Using the CyberKnife for Patients with Inoperable Locoregional Recurrences of Differentiated Thyroid Cancer

BACKGROUND

Surgical resection is the preferred treatment for locoregional recurrence of differentiated thyroid cancer (DTC). However, some recurrences are unresectable because of their aggressive invasion or severe adhesions. On the other hand, stereotactic radiotherapy (SRT) enables high-dose irradiation to target lesions, and its usefulness for various cancers has been reported. The objective of the present study was to investigate the feasibility and efficacy of SRT as salvage treatment for locoregional recurrence of DTC.

METHODS

Between August 2011 and December 2017, 52 locoregional recurrent lesions in 31 patients with recurrent DTC were treated by SRT using the CyberKnife system. Information on the adverse events associated with SRT was retrospectively collected from the patients' medical records. Of the 52 lesions, 33 could be evaluated for therapeutic effectiveness by follow-up CT, and response was assessed using the RECIST criteria.

RESULTS

Twenty-five patients had papillary carcinoma, 5 had follicular carcinoma, and 1 had poorly differentiated cancer. SRT was delivered in one to 20 fractions, and the median dose was 30 Gy (range 15-60 Gy). Adverse events were not frequent, but 1 patient developed bilateral vocal cord palsy that required emergent tracheostomy. The median follow-up period of 33 lesions was 14 months (range 1-54 months). Complete response, partial response, stable disease, and progressive disease were seen in 10, 11, 9, and 3 patients, respectively. The 3-year local control rate was 84.6%.

CONCLUSION

SRT using the CyberKnife system was found to be a feasible and effective treatment to suppress the growth of locoregional recurrence of DTC.

Correlations of lncRNAs with cervical lymph node metastasis and prognosis of papillary thyroid carcinoma

Background

Cervical lymph node metastasis is an important prognostic indicator for papillary thyroid carcinoma (PTC) and affects treatment strategies for PTC. lncRNAs essentially contribute to the biological functions of tumors. This study aimed to identify the lncRNAs associated with cervical lymph node metastasis and prognosis of PTC and their potential pathophysiological mechanisms.

Materials and methods

PTC-associated lncRNAs were selected from The Cancer Genome Atlas database, and correlations among lncRNAs, lymph node metastasis, tumor staging, and prognosis of PTC were analyzed in silico. These correlations were then validated through quantitative reverse transcription PCR (qRT-PCR) and immunohistochemistry (IHC).

Results

In silico analysis showed that FAM95B1 and UCA1 were significantly correlated with cervical lymph node metastasis, tumor staging, and PTC prognosis (P<0.05). qRT-PCR analysis revealed high UCA1 expression in PTC tissues and correlations between UCA1 expression levels and cervical lymph node metastasis and tumor staging in PTC, that is, higher UCA1 expression resulted in poorer PTC prognosis. IHC analysis revealed that a high expression of UCA1 was accompanied by a high expression of metastasis-related proteins (MMP-2 and MMP-9), thereby validating the correlation of UCA1 expression with metastasis.

Conclusion

FAM95B1 and UCA1 expression was significantly correlated with the occurrence and progression of PTC. The expression levels of UCA1 significantly affected the prognosis of PTC patients and were significantly correlated with tumor staging and cervical lymph node metastasis.

Differentiated thyroid cancer theranostics: radioiodine and beyond

The term theranostics is the combination of a diagnostic tool that helps to define the right therapeutic tool for specific disease. It signifies the "we know which sites require treatment (diagnostic scan) and confirm that those sites have been treated (post-therapy scan)" demonstrating the achievable tumor dose concept. This term was first used by John Funkhouser at the beginning of the 90s, at the same time the concept of personalized medicine appeared. In nuclear medicine, theranostics is easy to apply and understand because of an easy switch from diagnosis to therapy with the same vector. It helps in maximizing tumor dose and sparing normal tissue with high specific and rapid uptake in metastasis. The oldest application of this concept is radioactive iodine I-131 (RAI). The first treatment based on the theranostic concept was performed on thyroid cancer patients with RAI in 1946. From then on management of differentiated thyroid cancer (DTC) has evolved on the multimodality concept. We now use the term "our" patient instead of "my" patient to signify this. However, the initial surgical management followed by RAI as per the theranostics has remained the mainstay in achieving a cure in most of DTC patients. The normal thyroid cells metabolise iodine, the principle of which is utilized in imaging of the thyroid gland with isotopes of iodine. RAI treatment of DTC is based on the principle of sodium iodide symporter (NIS) expressing thyroid cells with DTC cells having the ability of trapping circulating RAI successfully helping in treatment of residual and metastatic disease. NIS is usually negative in poorly differentiated cells and is inversely proportional to Glucose transporter receptor Type 1 expression. Both positive and negative NIS are the key components of the theranostic approach in treatment of DTC. Presence or absence of NIS is documented by either whole body iodine scintigraphy (WBS) or 2-deoxy-2(18F) fludeoxyglucose (FDG) positron emission tomography computed tomography (PET-CT). Currently, single photon emission CT and CT (SPECT-CT) has significantly improved the precision and sensitivity of whole body iodine scintigraphy with its capability of accurate localization of disease foci whether iodine avid or non-avid. This has helped in a more personalized approach in treatment. This review will give an overview of the role of NIS in the theranostic approach to management with RAI, its current status and also the molecular approach to treatment in RAI refractory disease.

Regional Node Distribution in Papillary Thyroid Cancer with Microscopic Metastasis

Background

Optimal neck lymphadenectomy in patients with papillary thyroid cancer (PTC) and microscopic lymph node metastasis needs to be defined in order to aid surgeons in their decision about the best way to proceed in these cases.

Methods

Patients who underwent total thyroidectomy and lymphadenectomy at levels IIa to VI were divided into two groups: Group 1 (G1) with macroscopic metastasis detected before surgery and Group 2 (G2) with microscopic metastasis detected in sentinel node during surgery. Odds ratio (OR) was computed for age, sex, tumor size, multicentricity, capsular invasion, vascular/lymphatic permeation, and nodes with metastasis.

Results

Primary tumor size was (G1 versus G2, respectively) 3.8 cm versus 1.98 cm (P<0.001); only lymphatic permeation was correlated to an increase in metastasis in lymph nodes 65.4% versus 25% (OR=5.6, p<0.001); metastatic frequency by region was IIa 18.5% versus 1.5%, III 24.3% versus 9.9%, IV 17.4% versus 18.1%, and VI 25.9% versus 71,2%. Metastasis to level V was found only in G1.

Conclusion

Selective lymphadenectomy at levels III, IV, and VI is optimal for PTC patients without preoperative evidence of lymph node disease, but who present with lymph node microscopic metastasis in an intraoperative assessment.

RNA-sequencing investigation identifies an effective risk score generated by three novel lncRNAs for the survival of papillary thyroid cancer patients

Scholars are striving to apply molecular biology involving long non-coding RNA (lncRNA) in the prognostication of papillary thyroid cancer (PTC). However, the clinical role of lncRNAs in the prognostic setting of PTC is still unclear. Herein, a comprehensive inquiry was performed to screen lncRNA expression profiling with 507 PTC patients from The Cancer Genome Atlas RNA-sequencing datasets. A total of 734 lncRNAs were detected to be aberrantly expressed, among which three novel lncRNAs including AC079630.2, CRNDE and CTD-2171N6.1 were markedly related to the progression and survival of PTC. Furthermore, the aberrant expression of these lncRNAs could be verified by other cohorts from gene expression omnibus (GEO) as detected by microarrays. Next, we established a three-lncRNA signature and divided the PTC patients into two subgroups of high- and low-risk. Interestingly, patients with high-risk tended to gain obviously poorer outcome. Most importantly, this three-lncRNA signature was an independent biomarker to predict the patient survival of PTC. The accurate molecular roles of these three lncRNAs remains unclarified and warrants further characterization, but our current data propose that they might play pivotal roles in PTC tumorigenesis and more importantly, these novel lncRNAs are closely related to patients' survival. These discoveries will have far-reaching consequences with respect to molecular prediction of PTC.