Predictors for papillary thyroid cancer persistence and recurrence: a retrospective analysis with a 10-year follow-up cohort study

Recurrent Middle Eastern Differentiated Thyroid Carcinoma Has Worse Outcomes Than Persistent Disease

Background: Despite the excellent prognosis of differentiated thyroid carcinoma (DTC), recurrent and persistent disease remain major challenges. Emerging studies to differentiate between recurrent and persistent disease are controversial, with studies from the Middle East lacking. Methods: We retrospectively analyzed 1691 patients who underwent surgery ± I131 treatment for DTC, with a median age of 38.7 years and median follow-up of 95.3 months. Results: We found a similar prevalence rate for persistent and recurrent disease (17.7% vs. 17.9%) in Middle Eastern DTC patients. Relative to patients with persistent disease, patients with recurrent disease were significantly older (median age: 36.1 vs. 45.8 years; p < 0.0001) and were more likely to have ATA high-risk tumors (61.5% vs. 75.2%; p = 0.0003). On multivariate logistic regression analysis, both T and N status were independent predictors for recurrent as well as structural persistent disease. However, older age, bilaterality and extrathyroidal extension were independent predictors of recurrent disease alone. In addition, patients with recurrent disease had significantly worse cancer-specific survival (p < 0.0001), which remained significant in multivariate analysis. Conclusions: Although persistent and recurrent disease in Middle Eastern DTC have similar frequencies, recurrent disease has worse outcomes compared to persistent disease. Hence, differentiating recurrence from persistence has great potential clinical relevance for therapeutic and follow-up approaches, contributing to improving the outcomes of DTC patients of Middle Eastern ethnicity.

Nomogram incorporating preoperative clinical and ultrasound indicators to predict aggressiveness of solitary papillary thyroid carcinoma

Objective

To construct a nomogram based on preoperative clinical and ultrasound indicators to predict aggressiveness of solitary papillary thyroid carcinoma (PTC).

Methods

Preoperative clinical and ultrasound data from 709 patients diagnosed with solitary PTC between January 2017 and December 2020 were analyzed retrospectively. Univariate and multivariate logistic regression analyses were performed to identify the factors associated with PTC aggressiveness, and these factors were used to construct a predictive nomogram. The nomogram's performance was evaluated in the primary and validation cohorts.

Results

The 709 patients were separated into a primary cohort (n = 424) and a validation cohort (n = 285). Univariate analysis in the primary cohort showed 13 variables to be associated with aggressive PTC. In multivariate logistic regression analysis, the independent predictors of aggressive behavior were age (OR, 2.08; 95% CI, 1.30-3.35), tumor size (OR, 4.0; 95% CI, 2.17-7.37), capsule abutment (OR, 2.53; 95% CI, 1.50-4.26), and suspected cervical lymph nodes metastasis (OR, 2.50; 95% CI, 1.20-5.21). The nomogram incorporating these four predictors showed good discrimination and calibration in both the primary cohort (area under the curve, 0.77; 95% CI, 0.72-0.81; Hosmer-Lemeshow test, P = 0.967 and the validation cohort (area under the curve, 0.72; 95% CI, 0.66-0.78; Hosmer-Lemeshow test, P = 0.251).

Conclusion

The proposed nomogram shows good ability to predict PTC aggressiveness and could be useful during treatment decision making.

Advances in knowledge

Our nomogram-based on four indicators-provides comprehensive assessment of aggressive behavior of PTC and could be a useful tool in the clinic.

Coexisting CLT in PTC is an independent predictor of tumor aggressiveness for patients aged under 55: a retrospective analysis of 635 patients

BACKGROUND

The study was aimed at investigating the potential role of chronic lymphocytic thyroiditis (CLT) in papillary thyroid cancer (PTC) aggressiveness for patients aged below 55, as well as to figure out factors influencing potential recurrence risk in different age groups.

METHODS

A total of 635 adult patients were retrospectively analyzed. 188 patients were diagnosed with coexistent CLT and the remaining 447 were classified as non-CLT. Then the characteristics of CLT-coexisted patients and non-CLT ones were compared respectively when patients were aged ≥ 55 years or below. The association among postoperative clinicopathological features were also analyzed using multivariate regression. In addition, the prognostic value of several variables relating to high-risk recurrence were estimated within different age groups.

RESULTS

When divided in two age groups (55 years as the borderline), non-CLT group (aged below 55 years) had a remarkable frequency of small size lesion (D_max ≤ 1 cm) compared with CLT-coexisted patients (54.6% to 43.0%, p = 0.02). In addition, non-CLT patients tended to have intrathyroidal extension as opposed to those with coexistent CLT (20.2% to 28.2%, p = 0.05). In multivariate analysis, CLT still significantly acted as an independent risk factor of greater lesion size (D_min > 1 cm) (OR = 1.7, p = 0.02) and mildly promoted gross extrathyroidal extension (ETE) (OR = 1.4, p = 0.06). However, associations didn't emerge in the characteristics mentioned above with CLT when patients were ≥ 55 years old. The prognostic value of CLT in high-risk recurrence was evident only in patients aged 35-44 years. (OR = 2.4, 95%CI:1.2-5.4, p = 0.02). Greater lesion size independently promoted gross ETE, no matter patients were aged above 55 years or not. Its prognostic value of high-risk recurrence was significant throughout all age groups.

CONCLUSION

These findings revealed that CLT coexistence might be the unfavorable factor of PTC aggressiveness in patients aged below 55 years. Its role as well as greater tumor size may potentially predict higher recurrence risk according to results figured out in the prediction model.

Papillary Thyroid Cancer Prognosis: An Evolving Field

Simple Summary

Over the last couple of decades, the prognostic stratification systems of differentiated thyroid cancer (DTC) patients have been revised several times in an attempt to achieve a tailored clinical management reflecting the single patients’ needs. Such revisions are likely to continue in the near future, since the prognostic value of a number of promising clinicopathological features and new molecular biomarkers are being evaluated. Here, we will review the current staging systems of thyroid cancer patients and discuss the most relevant clinicopathological parameters and new molecular markers that are potentially capable of refining the prognosis.

Abstract

Over the last few years, a great advance has been made in the comprehension of the molecular pathogenesis underlying thyroid cancer progression, particularly for the papillary thyroid cancer (PTC), which represents the most common thyroid malignancy. Putative cancer driver mutations have been identified in more than 98% of PTC, and a new PTC classification into molecular subtypes has been proposed in order to resolve clinical uncertainties still present in the clinical management of patients. Additionally, the prognostic stratification systems have been profoundly modified over the last decade, with a view to refine patients’ staging and being able to choose a clinical approach tailored on single patient’s needs. Here, we will briefly discuss the recent changes in the clinical management of thyroid nodules, and review the current staging systems of thyroid cancer patients by analyzing promising clinicopathological features (i.e., gender, thyroid auto-immunity, multifocality, PTC histological variants, and vascular invasion) as well as new molecular markers (i.e., BRAF/TERT promoter mutations, miRNAs, and components of the plasminogen activating system) potentially capable of ameliorating the prognosis of PTC patients.

The age threshold of the 8th edition AJCC classification is useful for indicating patients with aggressive papillary thyroid cancer in clinical practice

BACKGROUND

Papillary thyroid cancer (PTC) is unique among cancers in that patient age is a consideration in staging. One of the most important modifications in the 8th Edition of the American Joint Committee on Cancer (AJCC) classification is to increase the age cut off for risk stratification in PTC from 45 to 55 years. However, whether this cut off is useful in clinical practice remains controversial. In the present study, we assessed how well this new age threshold stratifies patients with aggressive PTC.

METHODS

We retrospectively analyzed the clinicopathological features and overall survival rate of patients with PTC admitted to and surgically treated at a single surgical center. The study protocol was divided into two series. In each series all patients (n = 523) were divided in 2 groups according to age cut off. In the first series (cut off 45) patients < 45 (n = 193) vs. ≥45 (n = 330) were compared, and in the second series (cut off 55) patients < 55 (n = 306) vs. ≥55 (n = 217) were compared.

RESULTS

The rate of the prevalence of locally advanced disease (pT3 and pT4) was significantly higher in the patients above 55 years old than in those below 55 years old (p = 0.013). No significant differences were found for this parameter in series with cut off point 45 years old. A significantly higher risk of locally advanced disease T3 + T4 (OR = 4.87) and presence of LNM (N1) (OR = 3.78) was observed in ≥45 years old group (p = 0.021 and p < 0.0001, respectively). More expressive results were found for the patients ≥55 years old group, where the risk of locally advanced disease (T3 + T4) was higher (OR = 5.21) and LNM presence was OR = 4.76 (p < 0.001 and p < 0.0001, respectively). None of the patients below 55 years old showed distant metastasis, but 19 patients above 55 years old showed M1 (p < 0.0001). In older patients group (≥55 years old) we observed deaths related thyroid cancer in 11 individuals.

CONCLUSIONS

The age cut off of 55 years old for risk stratification proposed by the 8th Edition of AJCC effectively stratifies PTC patients with a poor prognosis, indicating it is likely to be useful in clinical practice.

NF-κB-Activated miR-574 Promotes Multiple Malignant and Metastatic Phenotypes by Targeting BNIP3 in Thyroid Carcinoma

Thyroid cancer is the most common endocrine malignancy, and miR-574 is significantly upregulated in thyroid cancer. However, the role and underlying mechanism of miR-574 in thyroid cancer development are poorly understood. In this study, we showed that NF-κB/p65 signaling pathway was activated and miR-574 was upregulated in thyroid cancer cells. p65 directly bound to the promoter of miR-574 and activated miR-574 transcription. Functionally, miR-574 inhibited apoptosis, promoted proliferation and migration of thyroid cancer cells, and stimulated thyroid cancer-induced tube formation of endothelial cells. On the molecular level, miR-574 inhibited the expression of BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3) by binding to 3'-UTR of BNIP3. miR-574 also downregulated the expression of apoptosis-inducing factor (AIF), while elevated the levels of MMP2, MMP9, and VEGFA. In vivo, miR-574 promoted xenograft growth, which was associated with reduced apoptosis and enhanced angiogenesis. NF-κB/miR-574 signaling presents multiple oncogenic activities on thyroid cancer development by directly regulating the BNIP3/AIF pathway. Therefore, targeting NF-κB/miR-574 signaling may reduce the aggressiveness of thyroid cancer. IMPLICATIONS: miR-574, directly regulated by NF-κB/p65, promotes tumorigenesis of thyroid cancer via inhibiting BNIP3/AIF pathway.

Microscopic Positive Tumor Margin Increases Risk for Disease Persistence but Not Recurrence in Patients with Stage T1-T2 Differentiated Thyroid Cancer

Introduction

Differentiated thyroid cancer (DTC) has an overall excellent prognosis. Patients who develop recurrent disease have a more unfavorable disease course than those with no recurrence. Higher recurrence rates are seen with incomplete surgical resection and gross positive margins. It is unclear whether microscopic positive margin affects disease recurrence rates as much as grossly positive margin. Aim of the Study. To assess whether microscopic positive margin is an independent predictor of disease recurrence in patients with overall low-risk DTC. Patients and Methods. We conducted a retrospective single-center institutional review of 1,583 consecutive patients' charts from 1995–2013 using the Canadian Thyroid Cancer Consortium Registry. We included adult patients with nonmetastasizing T1 and T2 DTC with a minimum of three years follow-up. Univariate and multivariate analyses were used to study factors that may influence the risk of persistent/recurrent disease. Strict definitions of persistent versus recurrent disease were applied.

Results

963 patients (152 men and 811 women) were included in the study with a mean age of 46 years. Microscopic positive margins were present in 12% of the specimens and were associated with an increased rate of persistent disease (8% versus 2% in the controls) but not with an increased risk of recurrent disease (1% in both groups). T2 tumors had a significantly higher incidence of positive margins than T1 tumors (48% versus 36%) and significantly higher nodal staging.

Conclusions

Microscopic positive margin in the histopathology report in patients with low-risk DTC was associated with a higher rate of persistent disease but did not increase the risk of disease recurrence. A close follow-up of biomarkers and occult residual cancerous lesions is needed, especially in the first year. Further studies are needed to determine whether additional therapeutic measures to prevent recurrence are indicated in T1 and T2 DTC with positive microscopic surgical margins.

Performance of ATA Risk Stratification Systems, Response to Therapy, and Outcome in an Indian Cohort of Differentiated Thyroid Carcinoma Patients: A Retrospective Study

INTRODUCTION

For better individualized management of differentiated thyroid carcinoma (DTC), ATA risk stratification systems (RSS) of 2009 and 2015 as well as a response to therapy re-classification (ATA RTR-2015) are used worldwide for assessing risk of recurrence. But there are no validation studies of these systems from the Indian subcontinent.

OBJECTIVES

To compare ATA RSS-2009, ATA RSS-2015, and ATA RTR-2015 for their accuracy in predicting outcome in DTC patients.

METHODS

This was a retrospective review of 236 adult patients with DTC >1 cm attending the Thyroid Cancer Clinic at our Institute who had undergone total thyroidectomy and radioactive iodine ablation. Initial risk stratification using ATA RSS-2009 and RSS-2015, clinical response at 1 year and outcome at last follow-up measured by clinical end points were collected and analyzed.

RESULTS

ATA RSS-2015 could not be applied to this cohort due to lack of histopathology details. While 77.3% of low-risk ATA RSS-2009 had disease-free status (NED, no evidence of disease) on follow-up, 96.1% of patients, in excellent response in ATA RTR-2015, showed NED. Whereas persistent structural disease was predicted by the high-risk group in ATA RSS-2009 (61.9%) and by the incomplete structural response group in ATA RTR-2015 (57.1%) equally well, the best predictor for NED at 1 year in this cohort was ATA RTR-2015 (p < 0.001).

CONCLUSION

This study found that both ATA RSS-2009 and ATA RTR-2015 are reliable in predicting outcome in DTC patients after initial treatment. However, the response to initial therapy at 1 year predicted outcome more accurately than the initial risk status.

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.

microRNA-510-5p promotes thyroid cancer cell proliferation, migration, and invasion through suppressing SNHG15

SNHG15 has been suggested to be correlated with clinical progression and prognosis, and function as tumor suppressive long noncoding RNA in thyroid cancer at our previous study. SNHG15 was proposed to be a potential target for miR-510-5p at LncBase Predicted database. Thus, the aim of this study was to explore the relationship between miR-510-5p and SNHG15 in thyroid cancer, and the clinical significance of miR-510-5p in patients with thyroid cancer. In our results, levels of miR-510-5p expression were increased in thyroid cancer tissues and cell lines compared with adjacent normal thyroid tissues and normal thyroid cell line, respectively. There was a statistically negative correlation between SNHG15 expression and miR-510-5p expression in thyroid cancer tissues. Moreover, miR-510-5p directly bound to SNHG15, and negatively regulated SNHG15 expression in thyroid cancer cells. Furthermore, miR-510-5p promoted thyroid cancer cell proliferation, migration, and invasion through suppressing SNHG15. Finally, high miR-510-5p expression was observed in tumor tissues with advanced clinical stage or lymph node metastasis. In conclusion, we provide evidence to support a pivotal role for miR-510-5p in regulating thyroid cancer cell proliferation, migration, and invasion.

Loss of nuclear localization of thyroid transcription factor 1 and adverse outcomes in papillary thyroid cancer

Function of the thyroid follicular cell depends on nuclear expression of thyroid transcription factor 1 (TTF1). Regulation of this key protein regulating iodide transport is not well known, but its loss is linked to the most lethal of thyroid malignancies. We examined TTF1 nuclear expression in the context of adverse pathological features, disease recurrence, and BRAF status in papillary thyroid carcinomas with (n = 182) and without (n = 303) nodal metastases. Overall nuclear expression level of TTF1 was strong and diffuse in approximately 73%, whereas 27% exhibited lower levels or a paucity of nuclear staining. In the same cohort, approximately 59% exhibited the BRAF mutation. On univariate analysis, low levels of TTF1 nuclear expression was linked to vascular invasion, extrathyroidal extension, and nodal metastases. Multivariate analysis indicated that low levels of TTF1 were most strongly linked to nodal metastases and vascular invasion. Interestingly, TTF1 levels were not linked to the BRAF mutation. TTF1 staining alone predicted disease recurrence, but when combined with BRAF status, the 2 markers exhibited a more marked influence. Patients lacking the BRAF mutation and exhibiting normal levels of TTF1 exhibited very low levels of disease recurrence (11% at 10 years). Conversely, patient tumors with low levels of TTF1 and the BRAF mutation recurred in 31% of cases in the same time frame. The mixed expression of BRAF under varying levels of differentiation may explain, in part, the contradictory studies regarding the impact of BRAF mutations on patient prognosis and also indicates a complex genomic signature for dedifferentiated thyroid cancer.

Time to Separate Persistent From Recurrent Differentiated Thyroid Cancer: Different Conditions With Different Outcomes

CONTEXT

Differentiated thyroid cancer (DTC) has an excellent prognosis, but up to 20% of patients with DTC have disease events after initial treatment, indistinctly defined as persistent/recurrent disease.

OBJECTIVE

To evaluate the prevalence and outcome of "recurrent" disease (relapse after being 12 months disease-free) compared with "persistent" disease (present ab initio since diagnosis).

DESIGN

Retrospective analysis of persistent/recurrent disease in patients with DTC (1990 to 2016) with 6.5 years of mean follow-up.

SETTING

Tertiary referral center for thyroid cancer.

PATIENTS

In total, 4292 patients all underwent surgery ± 131I treatment of DTC.

MAIN OUTCOME MEASURES

DTC cure of disease persistence or recurrence.

RESULTS

A total of 639 of 4292 (14.9%) patients had disease events after initial treatment, most (498/639, 78%) with persistent disease and 141 (22%) with recurrent disease. Relative to patients with recurrent disease, patients with persistent disease were significantly older (mean age 46.9 vs 45.7 years) and with a lower female to male ratio (1.9/1 vs 4.8/1). Moreover, in this group, structured disease was more frequent (65.7% vs 41.1%), and more important, distant metastases were significantly more frequent (38.4% vs 17.0%). At multivariate analysis, male sex (OR = 1.7), age (OR = 1.02), follicular histotype (OR = 1.5), T status (T3; OR = 3), and N status (N1b; OR = 7.7) were independently associated with persistent disease. Only the N status was associated with recurrent disease (N1b; OR = 2.5).

CONCLUSIONS

In patients with DTC not cured after initial treatment, persistent disease is more common and has a worse outcome than recurrent disease. Postoperative status evaluated during first-year follow-up may have important clinical implications for planning tailored treatment strategies and long-term follow-up procedures.

Expression of activator protein-1 in papillary thyroid carcinoma and its clinical significance

Background

The abnormal expression of activator protein-1(AP-1) has recently been investigated in a variety of tumors. While the relationship between AP-1 and thyroid cancer is poorly studied, our study was to evaluate the protein expression and clinical value of AP-1 in papillary thyroid carcinoma (PTC).

Methods

The expression of AP-1 was examined by immunohistochemistry on paraffin-embedded tissues obtained from PTC and correspondent paracancerous tissues of 82 patients.

Results

Compared with paracancerous tissues, AP-1 expression was significantly elevated in PTC tissues and the positive rate was 79.3% (65/82). Our study found a linear trend relationship between the expression of AP-1 and tumor size. However, the differences in AP-1 expression among gender, age, lymph node metastasis, number of lesions, location of the lesion, and extrathyroid invasion are not statistically significant.

Conclusions

The expression of AP-1 plays an important role in the proliferation process of PTC.

Molecular Predictors for Advanced Papillary Thyroid Carcinoma Recurrence

Despite its indolent course, one-third of the papillary thyroid carcinoma (PTC) cases relapses, which directly impact on the quality of patients' lives. The molecular predictors of recurrence of PTC are poorly defined. We aimed at evaluating the long-term (10-20 years) prognostic value of aggressiveness markers in advanced PTC. To this end, immunohistochemistry for BRAF^V600E, Estrogen receptor α, Progesterone receptor, Ki-67, and E-cadherin were performed in 53 primary advanced PTC from an up to 20 years follow-up patients from a well-characterized Brazilian cohort. Categorical data were summarized using frequencies and groups were compared using Chi-squared and Fisher's exact tests. The expressions of the aggressiveness markers were associated with clinical-pathological data using the single-covariate logistic regression analysis. The Kaplan-Meier method with the Log-rank and Peto tests was used to estimate the probability of PTC-free survival. Persistence and recurrence (active disease) were associated with age (≥55 years), tumor size (>2 cm), extrathyroidal extension, local aggressiveness, macroscopic lymph node metastasis, and TNM stage at initial treatment. The BRAF^V600E mutation status was associated with extrathyroidal extension, local aggressiveness, and inversely associated with distant metastasis at initial treatment. All progesterone receptor-positive patients had active disease and displayed a shorter time of PTC-free survival than the negative ones using the Kaplan-Meir analysis (p = 0.001, Log Rank; p = 0.005, Peto). Loss of E-cadherin expression was associated with an increase in the probability of active disease (OR = 3.75). BRAF^V600E could be useful as a biomarker of local aggressiveness, while PR positive and E-cadherin loss of expression could predict the recurrence of advanced PTC.

A cancer of undetermined significance: Incidental thyroid carcinoma

INTRODUCTION

The incidence of thyroid cancer is increasing which can be attributed in part to improved ultrasonography (US) methods and increased detection of incidental thyroid carcinomas (ITC). We aimed to compare ITC with nonincidental thyroid carcinomas (NITC) in this study.

METHODS

Retrospective analyses of 906 individual patients who were operated for benign and malignant thyroid disease and had a final histopathological diagnosis of thyroid carcinoma were enrolled in this study. Preoperative US examination and fine needle aspiration (FNA) biopsy results were evaluated. The tumor foci in thyroidectomy specimens that were not represented in preoperative US or FNA reports were classified as ITC. The tumor foci that match with the lesions defined in US or FNA results were classified as NITC.

RESULTS

Final histology revealed ITC in 326 patients (36%) and NITC in 580 patients (64% Mean age was 51.7 ± 11.11 in ITC group and 48.15 ± 13.1 in NITC group (P < .001). In NITC group 322 (55.5%) of the patients were operated for suspicious cytology while only 29 (8.9%) of the patients in the ITC group were operated because of this indication (P < .001). There were 1301 cancer foci in histopathology specimens. Among all these cancer foci, 434 (33.3%) were detected incidentally and 867 (66.7%) were detected non-incidentally. About 779 (89.9%) of nonincidental cancer foci were papillary cancer (PTC), while all of the incidental cancer foci were PTC. Mean size was 13 mm in NITC group and it was 3 mm in the ITC group and differed significantly between the groups (P < .001). Tumor size was ≤1 cm in 35.2% of the patients with NITC while 98.5% of patients with ITC had tumor ≤1 cm. The occurrence of multinodularity was higher in ITC than the NITC group (P < 001). Median TSH level was higher in patients with NITC than ITC while both were in the reference range (1.53 vs 1.03 μIU/mL, P < .001). The frequency of thyroiditis detected by US, and thyroid peroxidase antibody and thyroglobulin antibody positivities were similar in patients with ITC and NITC (P = .2, P = .86, and P = .26, respectively). The frequencies of capsular invasion (29.1% vs 7.9%), extrathyroidal extension (13% vs 4.2%), multifocality (35.8% vs 24.2%), non-complete resection (9.2% vs 1.8%), and lymph node metastasis (9.5% vs 1.8%) were significantly higher in the NITC group (P < .001, for each). Persistent/recurrent disease in patients with NITC was more frequent than patients with ITC (P = .004). This outcome was similar for cancers measuring ≤1 cm (P = .001).

CONCLUSION

ITC is often encountered in older patients and frequently determined in early stages with more favorable histopathological features and better prognosis.

Low-Activity Radioactive Iodine Therapy for Thyroid Carcinomas Exhibiting Nodal Metastases and Extrathyroidal Extension May Lead to Early Disease Recurrence

BACKGROUND

The application of radioactive iodine in differentiated thyroid carcinomas has become more selective in an attempt to decrease morbidity. While ablative success has been documented, it is less clear how changes in radioactive iodine treatment strategies will influence long-term recurrence rates for patients with larger tumors and adverse pathological features, including extrathyroidal extension and nodal metastases.

METHODS

Patients diagnosed between 1995 and 2008 with differentiated thyroid carcinoma treated with thyroidectomy followed by radioactive iodine treatment were eligible. All patients were followed for a minimum of five years using a standardized follow-up protocol requiring both biochemical and imaging assessments for recurrent disease (n = 219). Patients were stratified by initial radioactive iodine activity, and disease-free survival was calculated using the Kaplan-Meier method, with significant differences defined by the log-rank test.

RESULTS

In this cohort, 46% of patients had clinical metastases and 74% had primary tumors >1.5 cm. Patients who had recurrences were more likely to present with extrathyroidal extension (p = 0.002) and lymph node metastases at diagnosis (p < 0.001). Patients presenting with both extrathyroidal extension and lymph node metastases had a significantly worse time to progression if treated with <1850 MBq radioactive iodine compared to those patients treated with >1850 MBq (25 months vs. 121 months; p = 0.004). The use of lower-activity radioactive iodine ablative therapy was associated with more early recurrences (p = 0.003). Being aged younger or older than 45 years did not impact the time to recurrence nor did the use of level 6 dissection. On multivariate analysis, lymph node metastases at diagnosis and multiple applications of radioactive iodine were linked to increased risk of recurrence. Patients with neither, or only one, adverse pathologic feature had excellent outcomes, regardless of initial ablative activity, with <10% of patients recurring over a 10-year time span.

CONCLUSIONS

Recurrent disease in differentiated thyroid carcinoma is more common in patients treated with low-activity radioactive iodine in patients with lymph node metastases and extrathyroidal extension. These recurrences typically occur within four years of initial treatment. Patients lacking both of these risk factors treated with low radioactive iodine activity (<1850 MBq) have excellent outcomes, even after 10 years.

NKX2.5 is expressed in papillary thyroid carcinomas and regulates differentiation in thyroid cells

BACKGROUND

NKX2.5 is a transcription factor transiently expressed during thyroid organogenesis. Recently, several works have pointed out the oncogenic role of NKX2.5 in a variety of tumors. We therefore hypothesized that NKX2.5 could also play a role in thyroid cancer.

METHODS

The validation of NKX2.5 expression was assessed by immunohistochemistry analysis in a Brazilian case series of 10 papillary thyroid carcinoma (PTC) patients. Then, the long-term prognostic value of NKX2.5 and its correlation with clinicopathologic features of 51 PTC patients was evaluated in a cohort with 10-years follow-up (1990-1999). Besides, the effect of NKX2.5 overexpression on thyroid differentiation markers and function was also investigated in a non-tumor thyroid cell line (PCCL3).

RESULTS

NKX2.5 was shown to be expressed in most PTC samples (8/10, case series; 27/51, cohort). Patients who had tumors expressing NKX2.5 showed lower rates of persistence/recurrence (p = 0.013). Overexpression of NKX2.5 in PCCL3 cells led to: 1) downregulation of thyroid differentiation markers (thyrotropin receptor, thyroperoxidase and sodium-iodide symporter); 2) reduced iodide uptake; 3) increased extracellular H₂O₂ generation, dual oxidase 1 mRNA levels and activity of DuOx1 promoter.

CONCLUSIONS

In summary, NKX2.5 is expressed in most PTC samples analyzed and its presence correlates to better prognosis of PTC. In vitro, NKX2.5 overexpression reduces the expression of thyroid differentiation markers and increases ROS production. Thus, our data suggests that NKX2.5 could play a role in thyroid carcinogenesis.

Rationality in prophylactic central neck dissection in clinically node-negative (cN0) papillary thyroid carcinoma: Is there anything more to say? A decade experience in a single-center

AIM

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Despite its extremely favorable prognosis, cervical lymph node metastases are a common feature of PTC and a known independent risk factor for local recurrence. However, the role of prophylactic central neck dissection (PCND) remains a matter of debate in patients with clinically node-negative (cN0) PTC. To better clarify the current role of PCND in the surgical treatment of PTC, evaluating advantages and disadvantages of PCND and outcome of cN0 PTC patients who have been treated with either total thyroidectomy alone or in combination with PCND. A review of recent literature data is performed.

METHODS

Between January 2000 and December 2015, 186 consecutive patients with cN0 PTC were identified to be included in the present study. 74 of these underwent total thyroidectomy associated with PCND, while 112 patients underwent total thyroidectomy alone. The epidemiological and clinical-pathological data of all patients included were collected at diagnosis and during follow-up.

RESULTS

Overall complication rate was significantly higher in the group of patients undergoing PCND (39.2% vs. 17.8%, p = 0.0006). To be specific, they presented a considerably increased risk of temporary recurrent laryngeal nerve injury (p = 0.009) and of permanent hypothyroidism (p = 0.016). Overall survival and recurrence rates did not differ between those undergoing PCND and those undergoing total thyroidectomy alone (p = 1.000 and p = 0.715, respectively).

CONCLUSIONS

The results of the present study do not support the routine use of PCND in the treatment of cN0 PTC patients.

Clinical features of recently diagnosed papillary thyroid carcinoma in elderly patients aged 65 and older based on 10 years of sonographic experience at a single institution in Korea

Purpose

The aim of this study was to assess the characteristics of papillary thyroid carcinoma (PTC) in patients aged 65 and older in order to predict postoperative recurrence based on the results of ultrasonographic surveillance.

Methods

Among 1,494 patients (200 male and 1,294 female; mean age, 46.6±11.3 years) who underwent surgery for thyroid cancer at our institution between 2006 and 2015, we retrospectively enrolled 150 PTC patients (29 male and 121 female; mean age, 69.4±4.2 years). To identify the risk factors for recurrence, we analyzed age, gender, multiplicity, size, number, extrathyroidal extension (ETE) of the tumor, lymph node metastasis (LNM), type of surgery, and the dose of radioactive ablation using a Cox regression model to identify hazard ratios (HRs).

Results

Among the 115 asymptomatic patients with PTCs detected by screening ultrasonography (n=86), other cross-sectional imaging modalities (computed tomography or positron emission tomography-computed tomography, n=13), or incidentally through a surgical specimen (n=16), 78 patients were confirmed to have papillary thyroid microcarcinomas (PTMCs). The other 35 patients presented with palpable neck masses (n=25), vocal cord palsy (n=9) or blood-tinged sputum (n=1). During the follow-up period (mean, 43.6 months), 17 patients (12.5%) experienced recurrence in the neck. None of the patients died due to PTC-related recurrence or distant metastasis during the follow-up period. Cox regression analysis demonstrated that tumor size (HR, 2.12; P<0.001) and LNM (central LNM: HR, 9.08; P=0.004; lateral LNM: HR, 14.71; P=0.002; both central and lateral LNM: HR, 58.41; P<0.001) significantly increased the recurrence rate. ETE, LNM, and recurrence were significantly less frequent in PTMCs than in non-PTMC (all P<0.001).

Conclusion

PTCs of small size and absent LNM showed significantly better prognoses in patients 65 years and older.