Predicting recurrence of papillary thyroid cancer using the eighth edition of the AJCC/UICC staging system

Prognostic impact of lymph node characteristics after therapeutic neck dissection for classic N1 papillary thyroid cancer

BACKGROUND

The impact of lymph node characteristics on mortality and recurrence remains controversial. This study evaluated the prognostic impact of lymph node characteristics in a large, homogenous cohort of patients with therapeutic neck dissection for clinically N1 classic papillary thyroid cancer (PTC).

METHODS

All consecutive adult patients with therapeutic central and lateral neck dissection for PTC at a French referral centre were prospectively enrolled from January 2000 until June 2021. The primary outcome was the impact of lymph node characteristics in predicting a disease event (persistence or recurrence), using univariable and multivariable logistic regression modelling.

RESULTS

A total of 462 patients were included. Lymph node capsular rupture was seen in 260 patients (56.3 per cent). Median maximum lymph node size was 15 (i.q.r. 9-23) mm. The median central, lateral, and total lymph node ratio (LNR) was 0.50 (i.q.r. 0.22-0.75), 0.15 (i.q.r. 0.07-0.29), and 0.26 (i.q.r. 0.14-0.41), respectively. After a median follow-up of 93 (i.q.r. 50-149) months, 182 (39.4 per cent) patients had a disease event. After multivariable analysis, the number of harvested lymph node >35 (OR 2.33 (95 per cent c.i. 1.10-4.95)), presence of lymph node capsular rupture (OR 1.92 (1.17-3.14)), and total LNR >0.20 (OR 2.37 (1.08-5.19)) and >0.40 (OR 4.92 (1.61-15.03)) predicted a disease event. An LNR of 0.20 predicted a disease event with a sensitivity of 80.8 per cent and a specificity of 50.4 per cent.

CONCLUSION

Disease persistence or recurrence after thyroidectomy with therapeutic neck dissection for classic PTC with preoperative nodal disease appears to depend on number of harvested lymph node, presence of lymph node capsular rupture, and total LNR.

Primary tumour iodine avidity in relation to uptake in persistent metastatic disease in papillary and poorly differentiated thyroid cancer

PURPOSE

Patients with persistent or recurrent papillary and poorly differentiated thyroid cancer can be effectively treated with radioiodine, if the tumour tissue is iodine-avid. However, iodine-avidity status is often unknown at the time of initial radioiodine treatment, limiting any adaptive approach. This study aimed to clarify the relationship between pre-therapeutic iodine avidity in primary tumour tissue, initial lymph node metastases and iodine uptake in subsequent metastases.

METHODS

Iodine avidity was prospectively assessed pre-therapeutically in 35 patients by injection of tracer amounts of iodine-131 two days prior to surgery. Iodine concentrations in resected tissue samples were measured, enabling accurate and histologically verifiable iodine avidity data for both primary tumour and initial lymph node metastases. Iodine uptake in persistent metastatic disease was assessed by review of radiology, and treatment response was examined through journal studies.

RESULTS

Out of data from 35 patients, 10 had persistent disease at presentation or during follow-up (range 19-46 months). Four patients had non-avid persistent metastatic disease, all with low iodine avidity in their primary tumours and initial lymph node metastases. Patients with low pre-therapeutic iodine avidity did not appear to have greater risk of persistent disease.

CONCLUSION

The results indicate a close link between pre-therapeutically measured iodine concentrations in primary tumours with iodine avidity of any subsequent metastases.

Predictive value of systemic inflammatory markers for recurrence of papillary thyroid cancer

BACKGROUND

Papillary thyroid cancer (PTC) is the most common type of differentiated thyroid cancer. Early identification of patients at higher risk of recurrence may allow to improve relevant follow-up strategies and plan tailored treatment. Inflammation play an important role in the prognosis of cancer. We aimed to explore the predictive value of systemic inflammatory markers in PTC recurrence.

METHODS

We retrospectively enrolled 200 consecutive patients who were diagnosed with PTC and underwent curative resection at Lianyungang Oriental Hospital between January 2006 and December 2018. Clinicopathological characteristics, preoperative hematologic results were analyzed. The optimal cutoff values were calculated using x-tile software. The multivariate logistic regression and univariable survival analysis were performed by SPSS.

RESULTS

Multivariable analysis showed that lymph node metastases (odds ratio [OR] = 2.506, 95% confidence interval [CI]: 1.226-5.119, p = 0.012) and higher monocyte-to-lymphocyte ratio (MLR) (OR = 2.100, 95% CI: 1.042-4.233, p = 0.038) were independent prognostic factors for tumor recurrence. The cutoff value 0.22 of MLR significantly predicted recurrence at 53.3% sensitivity and 67.9% specificity. Patients with MLR ≥ 0.22 exhibited significantly poor long-term prognosis (46.8%) compared to the counterpart (76.8%, p = 0.0004).

CONCLUSIONS

Preoperative MLR significantly predicted PTC recurrence after curative resection, which may provide clues for early identification of patients at higher risk of PTC recurrence.

Comparison of staging and recurrence predictors in patients with differentiated thyroid cancer between the 7th and 8th editions of the American Joint Committee on Cancer staging systems

BACKGROUND

The predictive value of American Joint Committee on Cancer (AJCC) 8 for recurrence in differentiated thyroid cancer (DTC) is not known. We aimed to compare AJCC 7 and 8 regarding the differences in staging and recurrence predictors in DTC.

METHODS

Demographic, clinical (duration of disease and follow-up, the extent of surgery), laboratory (TSH, fT4, thyroglobulin, and antithyroglobulin), pathological (type of thyroid cancer, localization, multifocality, diameter, extrathyroidal extension [ETE], and lymph node [LN] metastasis), and imaging findings (sonography, and whole-body scan), and follow-up features (metastases, recurrence and/or persistence, and RAI need) were retrospectively analyzed in adult patients with DTC followed-up for at least six months. Staging was determined in accordance with AJCC 7 and AJCC 8, prediction of recurrence and persistence by ATA risk stratification, and death risk by AMES systems. The alterations in staging and recurrence predictors were analyzed.

RESULTS

A majority of study patients (N.=524) were female (N.=424) and diagnosed with papillary cancer (N.=511), the median age at diagnosis was 44. 97.89% (N.=93) of stage 2-4 patients (N.=95) in AJCC 7 were down-staged in AJCC 8. We down-staged 41 patients of 45-55 years of age into stage 1 in AJCC 8 independent of LN status. A percentage of 26.71% of patients (N.=140) did have persistence, 9.54% (N.=50) persistence at the last follow-up, and 9.54% (N.=50) had recurrence. According to AJCC 8, T4 and AMES high risk were predictors for recurrence (hazard ratio: 3.053, P=0.023; hazard ratio:2.465, and P=0.005; respectively). Both AJCC 7 and 8 were associated with recurrence (P=0.008 and P<0.001, respectively). Stage 4 in AJCC 7, and stages 3 and 4 in AJCC 8 better predicted the probability of recurrence.

CONCLUSIONS

Our findings suggest that AJCC 8 better predicted the recurrence in DTC than AJCC 7. In AJCC 8, T4 tumor, AMES high risk, stages 3 and 4 predicted recurrence. The vast majority of patients with stages 2-4 in AJCC 7 were down-staged in AJCC 8.

The proposed modification of TNM staging and therapeutic strategy for skip metastasis in papillary thyroid carcinoma: A multicenter retrospective cohort study

BACKGROUND

Skip metastasis is a special type of lateral lymph node metastasis, which is not classified definitely by the eighth edition of the AJCC TNM staging system. The aim of the research was to study the prognosis of skip metastasis in PTC patients, and carry out a more appropriate N staging for skip metastasis.

METHODS

Study subjects were 3167 patients with papillary thyroid carcinoma (PTC), who underwent thyroidectomy at three clinical centers from 2016 to 2019. We identified two well-balanced cohorts matched on the basis of propensity score.

RESULTS

During a median follow-up of 42 months, recurrence occurred in 68 (4.3%) patients with lymph node metastasis. 34 cases recurred in 1120 patients with central lymph node metastasis (N1a), and 34 recurred in 461 patients with lateral lymph node metastasis (N1b), among which 73 patients were diagnosis with skip metastasis. The RFS of N1a was significantly lower than that of N1b (p < 0.001). After propensity-score matching, recurrence rate was significantly lower in the skip metastasis group than in the LLNM group (p = 0.039), whereas the rate was similar in the skip metastasis groups and the CLNM group (p = 0.29).

CONCLUSIONS

In conclusion, our study indicated that, among patients with LLNM, those with positive skip metastasis showed significantly lower recurrence, exhibiting a similar rucurrence tendency as patients with CLNM. Thus, skip metastasis could be categorized into N1a stage rather than N1b stage based on the AJCC TNM staging system. The downstaging of skip metastasis may reveal more conservative treatment strategy.

Surgical outcomes of different approaches to dissection of lymph nodes posterior to right recurrent laryngeal nerve: a retrospective comparative cohort study of endoscopic thyroidectomy via the areolar approach and via the axillo-breast approach

Background

The American Thyroid Association (ATA) points out that lymph nodes posterior to right recurrent laryngeal nerve (LN-prRLN) should be routinely dissected. Due to the high risk of nerve injury, the lymph nodes in this area are difficult to dissect thoroughly. Although there are many approaches to endoscopic thyroidectomy, no study has been conducted on which one is more suitable. The purpose of this study was to evaluate the safety, thoroughness, related trauma, and feasibility of two widely used endoscopic thyroidectomy approaches, so as to provide a basis for the surgeon to select a better surgical approach.

Methods

This retrospective study included patients who underwent ETA (n=26) and ETAB (n=36). All patients had a pathological diagnosis of papillary thyroid carcinoma (PTC) and underwent endoscopic right thyroidectomy from May 2015 to February 2022 in the Affiliated Hospital of Nantong University. The basic clinical data and surgical outcomes of the two groups were compared.

Results

There was no statistical difference between the two groups in basic clinical data and oncological characteristics, which meant that the baseline data of the two groups of patients were comparable. Significant statistical significance was observed in the operation duration (149.38±44.15 vs. 119.22±45.48 min, P=0.011), drainage volume 24 h after operation (95.54±16.79 vs. 54.46±15.11 mL, P<0.001), visual analog score (VAS) 24 h after operation (3.69±1.44 vs. 2.25±1.32, P<0.001), hospitalization duration after the operation (3.19±0.75 vs. 2.25±0.44 days, P<0.001), number of lymph node dissections after right recurrent laryngeal nerve resection (0.96±1.08 vs. 2.06±1.77, P=0.007), and number of lymph node metastases after right recurrent laryngeal nerve resection (0.12±0.33 vs. 0.58±1.00, P=0.025). Besides, there was no significant difference in the numbers of central lymph node dissections and central lymph node metastases.

Conclusions

Our study indicated that compared with ETA, ETAB may perform a more efficient dissection of the LN-prRLN based on less surgical trauma, which could provide a basis for the surgeon to select a better surgical approach.

Significance of interstitial fibrosis and p16 in papillary thyroid carcinoma

We enrolled 264 patients with papillary thyroid carcinoma (PTC). We performed immunohistochemical detection of p16 and determined the degree of interstitial fibrosis (IF). The expression of p16 was associated with pathological tumor-node-metastasis (pTNM) stage and age (p < 0.05). The cancer-specific survival (CSS) was longer in p16-negative patients (195.73 vs. 181.78 months, p = 0.007). p16 was significantly related to the degree of IF (r = 0.130, p = 0.035). PTC patients with no or mild fibrosis tended to have a larger tumor (p = 0.045). The degree of fibrosis was related to the proportion of papillary structure components (p = 0.025). Univariate and multivariate survival analyses showed that relapse-free survival (RFS) was longer in patients with moderate/severe IF (p < 0.05). In summary, p16 was correlated with prognosis and IF of PTC. Patients with moderate/severe IF tend to have better prognosis in RFS.

Comprehensive analysis of lncRNA-mediated ceRNA regulatory networks and key genes associated with papillary thyroid cancer coexistent with Hashimoto's thyroiditis

OBJECTIVE

The incidence of papillary thyroid cancer (PTC) concomitant with Hashimoto's thyroiditis (HT) is gradually increasing over the past decades. This study aims to identify differentially expressed lncRNAs between tumor tissues of PTC with or without HT and further to confer a better understanding of lncRNA-based competing endogenous RNA (ceRNA) network in PTC with HT.

METHODS

GSE138198 containing tissue mRNA data and GSE192560 containing lncRNA data were utilized to perform differentially expression analysis. The ceRNA network was constructed based on miRNA-mRNA interactions merging with lncRNA-microRNA interactions. Functional enrichment analysis and protein-protein interaction (PPI) analysis were performed. The mRNA levels of core genes in the PPI analysis in tumor tissues collected from 112 PTC patients including 35 cases coexistent with HT were determined by quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

A total of 57 genes and 40 lncRNAs, with value of |log2 fold change (FC)|≥ 1 and the adjusted P-value < 0.05, were deemed as differentially expressed genes and lncRNAs between PTC with and without HT. The pathways most significantly enriched by differentially expressed genes between PTC with and without HT were viral protein interaction with cytokine and cytokine receptor and cytokine-cytokine receptor interaction. CXCL10, CXCL9, CCL5, FCGR3A, and CCR2 owned degree values not less than 10 were deemed as core genes differentially expressed between PTC with and without HT. A total of 76 pairs of lncRNA-miRNA-mRNA ceRNA were obtained. Results of qRT-PCR partially demonstrated the bioinformatics results that the mRNA levels of CXCL10, CXCL9, CCL5, and CCR2 were remarkably elevated in tumor tissues collected from PTC patients coexistent with HT than those without HT (P < 0.001).

CONCLUSION

Our study offers a better understanding of the lncRNA-related ceRNA network involved in PTC with HT, providing novel key genes associated with PTC coexistent with HT.

Lymph Node Metastases Identified at the Post-Ablation 131I SPECT/CT Scan Is a Prognostic Factor of Intermediate-Risk Papillary Thyroid Cancer

The intermediate-risk category of papillary thyroid cancer (PTC) comprises heterogeneous patients within a wide range of stages and varied care management. Understanding the risk features of recurrence observed after the initial therapy should be emphasized. We aimed to evaluate the prognostic significance of radioactive iodine-avid lymph nodes observed during the initial treatment of patients with PTC that were considered to be at intermediate risk. Data on patients with intermediate-risk PTC treated from 2012 to 2018 were retrospectively reviewed. Post-therapeutic SPECT/CT (Rx SPECT/CT) was evaluated in the enrolled patients. The clinical, pathologic, and incidence of radioiodine-avid (RAI-avid) lymph node metastasis (mLN) on Rx SPECT/CT were reviewed, and risk factors related to recurrent disease were analyzed. After a median follow-up of 37.26 (30.90, 46.33) months, structural persistent/recurrent disease was detected in 9.81% (36/367) of patients with intermediate-risk tumors. The incidence of recurrence was higher in patients who demonstrated RAI-avid mLN after the initial therapy than in those who did not (p < 0.001). In a multivariate Cox proportional hazard regression analysis, RAI-avid mLN appeared to be a robust risk factor for recurrent disease after the initial therapy (HR: 8.967, 95% CI: 3.433−23.421, p = 0.000). RAI-avid mLN is a significant risk factor for recurrent intermediate-risk PTC after the initial treatment.

A seven-autophagy-related gene signature for predicting the prognosis of differentiated thyroid carcinoma

Background

Numerous studies have implicated autophagy in the pathogenesis of thyroid carcinoma. This investigation aimed to establish an autophagy-related gene model and nomogram that can help predict the overall survival (OS) of patients with differentiated thyroid carcinoma (DTHCA).

Methods

Clinical characteristics and RNA-seq expression data from TCGA (The Cancer Genome Atlas) were used in the study. We also downloaded autophagy-related genes (ARGs) from the Gene Set Enrichment Analysis website and the Human Autophagy Database. First, we assigned patients into training and testing groups. R software was applied to identify differentially expressed ARGs for further construction of a protein-protein interaction (PPI) network for gene functional analyses. A risk score-based prognostic risk model was subsequently developed using univariate Cox regression and LASSO-penalized Cox regression analyses. The model’s performance was verified using Kaplan-Meier (KM) survival analysis and ROC curve. Finally, a nomogram was constructed for clinical application in evaluating the patients with DTHCA. Finally, a 7-gene prognostic risk model was developed based on gene set enrichment analysis.

Results

Overall, we identified 54 differentially expressed ARGs in patients with DTHCA. A new gene risk model based on 7-ARGs (CDKN2A, FGF7, CTSB, HAP1, DAPK2, DNAJB1, and ITPR1) was developed in the training group and validated in the testing group. The predictive accuracy of the model was reflected by the area under the ROC curve (AUC) values. Univariate and multivariate Cox regression analysis indicated that the model could independently predict the prognosis of patients with THCA. The constrained nomogram derived from the risk score and age also showed high prediction accuracy.

Conclusions

Here, we developed a 7-ARG prognostic risk model and nomogram for differentiated thyroid carcinoma patients that can guide clinical decisions and individualized therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02590-6.

Prophylactic bilateral central neck dissection should be evaluated based on prospective randomized study of 581 PTC patients

BACKGROUND

Prophylactic central lymph node dissection (PCND) was a basic consensus for patients with papillary thyroid carcinoma (PTC) in China. However, unilateral or bilateral central lymph node dissection (CND) was still controversial. This study aimed at investigating the safety and long-term benefit for the patients undergone with bilateral central lymph node dissection (BCCD).

METHODS

581 patients were enrolled and divided randomly into the test and control groups according to range of CND. 285 patients were prospectively assigned to undergo thyroid lobectomy plus BCND in the test group, other 296 patients were assigned to undergo thyroid lobectomy plus ipsilateral central lymph node dissection (ICND) in the control group.

RESULTS

We found that the numbers of total LN and pN1a in the test group were more than that of the control group (p = 0.002,0.004), but there was no difference in the number of metastasized lymph nodes (p = 0.857) and tumor recurrence (p = 0.308). Additionally, in the aspect of postoperative complication (1 day after surgery), the serum levels of parathyroid hormone in the BCND group were lower than that in the ICND group (P = 0.010), and the numbers of transient laryngeal nerve palsy were more than that(p = 0.033). Meanwhile, we further found that pathological tumor size larger than 1 cm and tumor side lymph node metastasis were independent risk factors for contralateral central lymph node metastasis(p = 0.002,0.001).

CONCLUSION

BCND may be an alternative for patients with tumor sizes larger than 1 cm, but it would significantly increase the rate of transient vocal cord palsy, parathyroid auto transplantation and decreased PTH, but the risk of permanent complications was similar to the ICND group.

Serum Linkage-Specific Sialylation Changes Are Potential Biomarkers for Monitoring and Predicting the Recurrence of Papillary Thyroid Cancer Following Thyroidectomy

BACKGROUND

Although papillary thyroid cancer (PTC) could remain indolent, the recurrence rates after thyroidectomy are approximately 20%. There are currently no accurate serum biomarkers that can monitor and predict recurrence of PTC after thyroidectomy. This study aimed to explore novel serum biomarkers that are relevant to the monitoring and prediction of recurrence in PTC using N-glycomics.

METHODS

A high-throughput quantitative strategy based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to obtain serum protein N-glycomes of well-differentiated PTC, postoperative surveillance (PS), postoperative recurrence (PR), and matched healthy controls (HC) including linkage-specific sialylation information.

RESULTS

Serum N-glycan traits were found to differ among PTC, PS, PR, and HC. The differentially expressed N-glycan traits consisting of sixteen directly detected glycan traits and seven derived glycan traits indicated the response to surgical resection therapy and the potential for monitoring the PTC. Two glycan traits representing the levels of linkage-specific sialylation (H4N3F1L1 and H4N6F1E1) which were down-regulated in PS and up-regulated in PR showed high potential as biomarkers for predicting the recurrence after thyroidectomy.

CONCLUSIONS

To the best of our knowledge, this study provides comprehensive evaluations of the serum N-glycomic changes in patients with PS or PR for the first time. Several candidate serum N-glycan biomarkers including the linkage-specific sialylation have been determined, some of which have potential in the prediction of recurrence in PTC, and others of which can help to explore and monitor the response to initial surgical resection therapy. The findings enhanced the comprehension of PTC.

Concepts of Pathological Staging and Prognosis in Papillary Thyroid Carcinoma

American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (AJCC/UICC) staging and American Thyroid Association (ATA) risk predication system are the best predicators of mortality and cancer recurrence, respectively, in patients with differentiated thyroid carcinoma, including papillary thyroid carcinoma. In ATA risk stratification of differentiated thyroid carcinomas, clinical features, nodal features, and pathological features are assessed. Many of the features are also assessed in pathological staging. The prognostic stage grouping of papillary thyroid carcinoma in AJCC/UICC depends on the age of the patients as well as the standard parameters-extent of tumor (T), lymph node status (N), and presence of distant metastasis (M). Major changes noted in the current pathological staging protocol include the cut-off age from 45-year to 55-year in grouping of patients, use of gross invasion of strap muscles instead of minimal microscopic extrathyroidal extensions as T3b and downstage of many prognostic groups such as those with lymph node metastases (without distant metastases) from Stage III to Stage II. The staging protocol have moved many patients with papillary thyroid carcinoma into good prognostic groups for better predication of patients' survival rates and to avoid unnecessary treatment. This new approach has been verified by different groups globally, although modifications could be expected in the future for better prognostic assessment in patients with papillary thyroid carcinoma.

Microscopic Extrathyroidal Extension Results in Increased Rate of Tumor Recurrence and Is an Independent Predictor of Patient’s Outcome in Middle Eastern Papillary Thyroid Carcinoma

Background

Papillary Thyroid Cancer (PTC) is the most common endocrine malignancy, with recurrence rate as high as 30%. A great deal of controversy surrounds the significance of microscopic extrathyroidal extension (m-ETE) as a prognostic factor. The most recent edition (8^th) of American Joint Committee on Cancer (AJCC) staging system has removed m-ETE from the definition of pT3, which suggests that m-ETE may lack prognostic impact in PTC patients. Moreover, data about m-ETE prevalence and clinical impact on Middle Eastern PTC remains unknown. We therefore investigate the prevalence of m-ETE and its clinico-pathological correlation and prognostic impact in Middle Eastern PTC. We also compared the AJCC 7^th and 8^th staging systems and their prognostic performance.

Methods

PTCs from 1430 consecutive adult (> 18 years) patients from single tertiary care hospital were included in this study. A retrospective analysis of PTC patients’ survival and recurrence were compared between AJCC 8^th and AJCC 7^th staging systems using Proportion of Variation Explained (PVE) and Harrell’s C-index.

Results

Median follow up of the study cohort was 9.3 years. 31.2% (446/1430) of patients had m-ETE. In the overall cohort, m-ETE was associated with multiple adverse features such as older age (p < 0.0001), male sex (p = 0.0245), tall cell variant (p < 0.0001), bilateral tumors (p < 0.0001), multifocality (p < 0.0001), lymphovascular invasion (p < 0.0001), lymph node metastasis (p < 0.0001), distant metastasis (p = 0.0166), tumor recurrence (p < 0.0001), radioactive iodine refractoriness (p < 0.0001), BRAF mutation (p < 0.0001) and reduced recurrence-free survival (RFS; HR = 1.75; 95% CI = 1.30 – 2.35; p < 0.0001) irrespective of tumor size. Of the 611 patients with T3 disease based on AJCC 7^th edition, 359 (58.8%) were down-staged in AJCC 8^th edition classification. Overall, the prognostic performance of AJCC 8^th edition was inferior to AJCC 7^th on the basis of lower PVE (3.04% vs. 3.73%) and lower C-index (0.40 vs. 0.48).

Conclusions

In Middle Eastern PTC, m-ETE is significantly associated with compromised survival and acts as an independent predictor of RFS. Given these findings, m-ETE should be included in the thyroid cancer treatment guidelines.

Survival in differentiated thyroid carcinoma: Comparison between the 7th and 8th editions of the AJCC/UICC TNM staging system and the ATA initial risk stratification system

BACKGROUND

The AJCC/UICC TNM staging system evaluates the risk of death from cancer. Its 8th edition aimed to increase its accuracy. In turn, the American Thyroid Association proposed an initial risk stratification system (IRSS) focusing on the risk of recurrence in differentiated thyroid carcinoma. The present study intended to analyze their prediction abilities.

METHODS

Six hundred and eighty-five consecutive surgical patients (mean follow-up 71.6 months) were staged. Correlations with disease-free survival (DFS) and overall survival (OS) were carried out.

RESULTS

IRSS was discriminative for DFS but not for OS. Applying TNM 8th, 36.9% of the cohort was downstaged. Their DFS was shorter, compared with other patients in the same stage, but with no impact on OS. However, all those who died of the disease had been downstaged.

CONCLUSIONS

IRSS was more effective to predict DFS, but not OS. TNM 8th was more appropriate for OS analysis than TNM 7th and IRSS.

European Thyroid Association and Cardiovascular and Interventional Radiological Society of Europe 2021 Clinical Practice Guideline for the Use of Minimally Invasive Treatments in Malignant Thyroid Lesions

The growing detection of papillary thyroid microcarcinomas (PTMCs) is paralleled by an increase in surgical procedures. Due to the frequent indolent nature, cost, and risk of surgery, active surveillance (AS) and ultrasound-guided minimally invasive treatments (MITs) are in suitable cases of incidental PTMC proposed as alternatives to thyroidectomy. Surgery and radioiodine are the established treatments for relapsing cervical differentiated thyroid carcinoma (DTC) metastases. But radioiodine refractoriness, risk of surgical complications, adverse influence on quality of life, or declining repeat surgery have led to AS and MIT being considered as alternatives for slow-growing DTC nodal metastases. Also, for distant radioiodine-refractory metastases not amenable to surgery, MIT is proposed as part of a multimodality therapeutic approach. The European Thyroid Association and the Cardiovascular and Interventional Radiological Society of Europe commissioned these guidelines for the appropriate use of MIT. Based on a systematic PubMed search, an evidence-based approach was applied, and both knowledge and practical experience of the panelists were incorporated to develop the manuscript and the specific recommendations. We recommend that when weighing between surgery, radioiodine, AS, or MIT for DTC, a multidisciplinary team including members with expertise in interventional radiology assess the demographic, clinical, histological, and imaging characteristics for appropriate selection of patients eligible for MIT. Consider TA in low-risk PTMC patients who are at surgical risk, have short life expectancy, relevant comorbidities, or are unwilling to undergo surgery or AS. As laser ablation, radiofrequency ablation, and microwave ablation are similarly safe and effective thermal ablation (TA) techniques, the choice should be based on the specific competences and resources of the centers. Use of ethanol ablation and high-intensity focused ultrasound is not recommended for PTMC treatment. Consider MIT as an alternative to surgical neck dissection in patients with radioiodine refractory cervical recurrences who are at surgical risk or decline further surgery. Factors that favor MIT are previous neck dissection, presence of surgical complications, small size metastases, and <4 involved latero-cervical lymph nodes. Consider TA among treatment options in patients with unresectable oligometastatic or oligoprogressive distant metastases to achieve local tumor control or pain palliation. Consider TA, in combination with bone consolidation and external beam radiation therapy, as a treatment option for painful bone metastases not amenable to other established treatments.

Patient Perspectives on the Extent of Surgery and Radioactive Iodine Treatment for Low-Risk Differentiated Thyroid Cancer

OBJECTIVE

To understand patient perspective regarding recommended changes in the 2015 American Thyroid Association (ATA) guidelines. Specifically, in regard to active surveillance (AS) of some small differentiated thyroid cancer (DTC), performance of less extensive surgery for low-risk DTC, and more selective administration of radioactive iodine (RAI).

METHODS

An online survey was disseminated to thyroid cancer patient advocacy organizations and members of the ATA to distribute to the patients. Data were collected on demographic and treatment information, and patient experience with DTC. Patients were asked "what if" scenarios on core topics, including AS, extent of surgery, and indications for RAI.

RESULTS

Survey responses were analyzed from 1546 patients with DTC: 1478 (96%) had a total thyroidectomy, and 1167 (76%) underwent RAI. If there was no change in the overall cancer outcome, 606 (39%) of respondents would have considered lobectomy over total thyroidectomy, 536 (35%) would have opted for AS, and 638 (41%) would have chosen to forego RAI. Moreover, (774/1217) 64% of respondents wanted more time with their clinicians when making decisions about the extent of surgery. A total of 621/1167 of patients experienced significant side effects with RAI, and 351/1167 of patients felt that the risks of treatment were not well explained. 1237/1546 (80%) of patients felt that AS would not be overly burdensome, and quality of life was the main reason cited for choosing AS.

CONCLUSION

Patient perspective regarding choice in the management of low-risk DTC varies widely, and a large proportion of DTC patients would change aspects of their care if oncologic outcomes were equivalent.

Features of Lymph Node Metastasis and Structural Recurrence in Papillary Thyroid Carcinoma Located in the Upper Portion of the Thyroid: A Retrospective Cohort Study

BACKGROUND

This study aims to reveal the features of lymph node metastasis (LNM) and recurrence in papillary thyroid carcinoma (PTC) tumors located in the upper portion of the thyroid.

METHODS

A total of 1075 PTC patients were retrospectively reviewed, including 314 patients with a tumor in the upper portion of the thyroid. Another 103 PTC patients with upper portion diagonsis from three clinical centers were included for external validation.

RESULTS

The results showed no difference between the patients with a tumor in the upper portion of the thyroid and those with a tumor in the non-upper portion in terms of overall LNM rates. However, patients with a tumor in the upper portion were significantly more prone to LLNM and exhibited a significantly worse recurrence outcome than those with a tumor in other subregions. Multivariate analysis showed that four factors-age no more than 40, maximum tumor diameter no less than1.0 cm, the presence of thyroid capsular invasion, and tumor with ipsilateral nodular goiter-were independent risk factors for LLNM of the tumor in the upper thyroid. A predictive risk-scoring model was established based on these factors.

CONCLUSIONS

Patients with PTC located in the upper portion may have an exclusive lymphatic drainage pathway to the lateral neck region and are more prone to suffer from LLNM and tumor recurrence than those with a tumor located in other subregions. A new postoperative strategy selection flow chart was established based on our newly created risk-scoring model that can effectively predict the individualized possibility of LLNM for PTC patients with a tumor in the upper portion.

Evaluation of Clinicopathological and Molecular Parameters on Disease Recurrence of Papillary Thyroid Cancer Patient: A Retrospective Observational Study

Simple Summary

Papillary thyroid cancer (PTC) patients are staged according to the Tumor-Node-Metastasis staging system (TNM). This work was aimed at comparing the usefulness of the 8th edition of TNM (TNM-8), currently used, and that of the previous one (TNM-7) for predicting disease-free interval (DFI) in a cohort of 1148 patients. Moreover, clinicopathological and molecular factors were statistically evaluated in order to determine which of these was/were the best predictor(s) of DFI. Results obtained from the multivariate analysis indicated that advanced tumor stages were independent risk factors for a lower DFI regardless of TNM, but the statistical model created with the TNM-7 was most accurate. When stage-determining factors were included individually in the multivariate analysis, LN metastases, tall cell variant, and age emerged as independent risk factors for a shorter DFI, with lateral LN metastases being the most relevant. No molecular parameters could improve the prediction of DFI provided by LN metastases.

Abstract

The American Joint Committee on Cancer has revised the Tumor-Node-Metastasis (TNM) staging system for papillary thyroid cancer (PTC) patients. We examined the impact of this new classification (TNM-8) on patient stratification and estimated the prognostic value of clinicopathological features for the disease-free interval (DFI) in a cohort of 1148 PTC patients. Kaplan–Meier analyses showed that all clinicopathological parameters analyzed, except age and multifocality, were associated significantly with DFI. Cox regression identified tall cell PTC variant and stage as independent risk factors for DFI. When the stage was replaced with age, tumor size, and lymph node (LN) metastases in the set of covariates, the lateral LN metastases stood out as the strongest independent predictor of DFI, followed by tall cell variant and age. A noteworthy result emerging from these analyzes is that regression models had lower Akaike and Bayesian information criterions if variables were categorized based on the TNM-7. In addition, we examined data from a different PTC patient cohort, acquired from The Cancer Genome Atlas database, to verify whether the DFI prediction could be enhanced by further clinicopathological and molecular parameters. However, none of these was found to be a significant predictor of DFI in the Cox model.

5-Hydroxymethylcytosine as a potential epigenetic biomarker in papillary thyroid carcinoma

DNA methylation at the 5 position of cytosine (5-mC) is an epigenetic hallmark that is critical in various biological and pathological processes such as DNA methylation regulation, and initiation and development of cancers. 5-mC can be oxidized to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation family of DNA hydroxylases. Accumulating evidence has reported that loss of 5-hmC is associated with cancer development. However, its level in papillary thyroid carcinoma (PTC) remains unclear. The present study reports that the loss of 5-hmC is an epigenetic mark of PTCs, associated with their malignant biological behavior, providing diagnostic and predictive advantages over DNA hypomethylation (5-mC), an acknowledged epigenetic alteration in cancer. In addition, the 5-hmC staining levels were decreased in cases of micro-carcinoma with lymph node metastasis, which suggests that 5-hmC expression levels could be used as valuable biomarkers for predicting malignant potential and assist in the selection of therapeutic strategies in PTC; therefore, 5-hmC has the potential to provide a more precise direction for PTC therapy.