Prognosis of multifocal papillary thyroid carcinoma

Survival benefits of extensive surgery in patients with papillary thyroid microcarcinoma

BACKGROUND

Despite the guidelines recommending thyroid lobectomy, many papillary thyroid microcarcinoma (PTMC) patients still undergo total thyroidectomy. PTMC's optimal treatment remains unclear. We aimed to determine whether total thyroidectomy improves outcomes compared to less extensive surgery.

METHODS

We analyzed 6064 PTMC adult patients from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2019) who underwent either total thyroidectomy (n ​= ​3652) or less extensive surgery (n ​= ​2412). Endpoints were overall survival, cancer-specific survival, and recurrence.

RESULTS

Total thyroidectomy patients had a 5.2 ​% mortality rate versus 8.1 ​% with less extensive surgery. Recurrence occurred in 1 (0.03 ​%) total thyroidectomy patient compared to 24 (1.0 ​%) less extensive surgery patients (HR 0.07, p ​= ​0.01). Median survival was 8.1 years for total thyroidectomy versus 8.8 years for less extensive surgery. Overall survival favored total thyroidectomy (p ​= ​0.001) but cancer-specific survival did not differ.

CONCLUSION

Although total thyroidectomy may not improve cancer-specific survival, it lowers recurrence risk and confers an overall survival advantage for PTMC patients. These findings may help guide surgical decisions.

The Impact of Total Tumor Diameter on Lymph Node Metastasis and Tumor Recurrence in Papillary Thyroid Carcinomas

(1) Introduction: The impact of multifocality/bilaterality on the prognosis of papillary thyroid carcinoma (PTC) is a matter of debate. In order to clarify this debate, several studies have attempted to identify additional parameters associated with poor prognosis, including total tumor diameter (TTD), in the context of multifocal PTCs. In this context, this study was carried out to investigate the impact of TTD on tumor recurrence and lymph node metastasis (LNM) in PTCs. (2) Materials and Methods: The sample of this single-center retrospective study consisted of 706 patients diagnosed with PTC. TTD was calculated as the sum of the largest diameters of tumor foci in multifocal tumors. The resulting TTDs were grouped into TTDs ≤ 10 mm, TTDs > 10 mm, TTDs ≤ 20 mm, and TTDs > 20 mm, using 10 mm and 20 mm as cutoff values. (3) Results: There was no significant difference between multifocal papillary microcarcinomas (PTMCs) with a TTD of >10 mm and unifocal PTCs with a primary tumor diameter (PTD) of >10 mm except for advanced age and lymphovascular invasion (LVI). In addition, perineural invasion (PNI) and TTD > 10 mm were found to be significant risk factors for LNM, and PNI, TTD > 10 mm, TTD > 20 mm, and bilaterality were found to be significant risk factors for recurrence. LVI, and TTD > 10 mm were found to be independent significant predictors for recurrence, and LVI and extrathyroidal extension (ETE) were found to be independent significant predictors for LNM. (4) Conclusions: Considering TTD > 10 mm in recurrence risk categorization models and adopting a clinical approach that takes into account multifocal PTMCs with TTD > 10 mm along with unifocal PTCs with PTD > 10 mm may be more useful in terms of clinical management of the disease.

Preoperative risk stratification for patients with ≤ 1 cm papillary thyroid carcinomas based on preoperative blood inflammatory markers: construction of a dynamic predictive model

Objective

The aim of this study was to investigate the relationships and predictive value of preoperative peripheral blood inflammatory markers as a means by which to assess risk for patients with ≤ 1 cm papillary thyroid carcinomas (PTCs). In addition, a preoperative risk stratification predictive model was constructed and validated.

Methods

Clinical and pathologic data, as well as preoperative blood specimens, were collected from patients who underwent initial thyroid cancer surgery at the Hangzhou First People's Hospital, from January 2014 to January 2023. Risk assessment was performed based on postoperative pathology according to the 2015 ATA guidelines for recurrence risk stratification. Using univariate analysis and multivariate logistic regression, we identified independent risk factors associated with risk stratification. A predictive model was established and its discriminative and calibration abilities were validated. An independent validation dataset was used to verify the model, and the model was deployed as an online calculator.

Results

A total of 1326 patients were included in the study, with 1047 cases (79.0%) classified as low risk and 279 cases (21.0%) classified as intermediate to high risk. The modeling group consisted of 981 cases, through univariate analysis and multivariate logistic regression analysis, preoperative blood Neutrophil/Lymphocyte Ratio (NLR), gender, tumor diameter, and multifocality were identified as independent risk factors that distinguished between low and intermediate to high risk patients with ≤ 1 cm PTCs. The clinical predictive model exhibited an AUC of 0.785, specificity of 70.6%, and sensitivity of 75.8%. For the independent validation group of 345 patients, the AUC was 0.813, specificity was 83.8%, and sensitivity was 70.4%. The calibration curve and clinical decision curve indicate that the model demonstrates excellent calibration performance.

Conclusion

A dynamic clinical predictive model based on preoperative blood NLR and clinical information for patients with ≤ 1 cm PTCs was established. The model is useful for preoperative risk assessment of patients with ≤ 1 cm PTCs.

Multifocal papillary thyroid cancer in Graves' disease: A case report

BACKGROUND

Thyroid cancer is not commonly observed in patients with Graves' disease (GD). The presence of thyroid nodules in GD is not uncommon. However, a link between these two entities has been reported. Herein, we report the case of a patient with GD and thyroid cancer in Saudi Arabia, which has not been reported previously in our region.

CASE SUMMARY

A 26-year-old male patient with GD, receiving carbimazole for 2 years, presented to our hospital. His hyperthyroidism was controlled clinically and biochemically. On clinical examination, he was found to have a left-sided thyroid nodule. Ultrasound revealed a 2.6 cm hypoechoic nodule with high vascularity. He was then referred for fine needle aspiration which showed that the nodule was highly suspicious for malignancy. The patient underwent total thyroidectomy and was diagnosed with multifocal classical micropapillary thyroid cancer. Post thyroidectomy he received radioactive iodine ablation along with levothyroxine replacement therapy.

CONCLUSION

Careful preoperative assessment and thyroid gland ultrasound might assist in screening and diagnosing thyroid cancer in patients with GD.

Association between papillary thyroid carcinoma and lymphocytic thyroiditis: A retrospective study

The aim of the present study was to evaluate the association between coexisting lymphocytic thyroiditis (LT) and the clinicopathological features of papillary thyroid carcinoma (PTC). The records of 458 patients with PTC who underwent a total thyroidectomy and lymph node dissection in Sir Run Run Shaw Hospital (Hangzhou, China) were analyzed. In accordance with the histopathology of thyroid parenchyma, the cases were divided into three groups, including Hashimoto's thyroiditis (HT), non-Hashimoto's type LT (NHLT) and no LT. Based on the histopathology, data on age, sex, maximum diameter of tumor, multifocality, extrathyroidal extension, metastatic lymph node size, extranodal extension and tumor grades in the different groups were analyzed and compared. The prevalence of coexisting LT was 29.0% (133/458), of which 7.6% (35/458) was HT and 21.4% (98/458) was NHLT. PTC concomitant with LT was significantly associated with female patients (95.5 vs. 70.2%; P<0.001), a lower rate of extrathyroidal extension and/or capsular invasion (25.6 vs. 39.7%; P=0.004), central lymph node metastasis (CLNM) ratio (10.71 vs. 17.37; P=0.014), higher number of dissected central lymph nodes (16.83 vs. 11.7; P<0.001), larger metastatic lymph nodes (0.66 vs. 0.46 cm; P<0.001), higher occurrence of multifocality (61.7 vs. 50.5%; P=0.029) and earlier pT stage (57.9 vs. 38.8%; P<0.001), regardless of the combined or separate consideration of HT and NHLT. Besides, LT was associated with multifocality [odds ratio (OR), 1.578; 95% confidence interval (CI), 1.046-2.382; P=0.030]. Furthermore, in patients with PTC, CLNM had a significant association with the male sex (OR, 2.000; 95% CI, 1.216-3.288; P=0.006), an age of <45 years (OR, 0.592; 95% CI, 0.398-0.879; P=0.009) and a tumor size of >1 cm (OR, 3.913; 95% CI, 2.431-5.734; P<0.001). In conclusion, patients with PTC and LT showed a greater female preponderance, multifocality, a lower extrathyroidal extension and a lower CLNM ratio. LT was associated with an increased risk of multifocality in PTC.

Risk factor score for the prediction of central compartment lymph node metastasis in papillary thyroid carcinoma and its clinical significance

Objective

To establish the criteria for a risk factor score (RFS) for predicting the probability of central compartment lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) and to explore the clinical significance of the RFS.

Methods

The data of 412 patients with PTC who underwent surgical resection between May 2013 and July 2016 were retrospectively analysed and divided into two groups: a central LNM group and a non-central LNM group. In each group, the frequency of six risk factors was documented: sex, age, tumour size, extracapsular spread (ECS), tumour multifocality, and tumour location. The maximum likelihood method of discriminant analysis was adopted to calculate patient scores for the six risk indicators. In addition, the data of 104 patients with PTC admitted between July 2016 and December 2016 were prospectively analysed using this method and these six risk factors. A higher score represented one certain possibility that was the more appropriate for one patient.

Results

In the retrospective group, the result was as follows: 129 patients with positive (+) lymph nodes in the central compartment and 168 patients with negative (−) lymph nodes in the central compartment, which was in line with the actual results. In the prospective group, there were 28 patients with positive lymph nodes in the central compartment and 48 patients with negative lymph nodes in the central compartment. The coincidence rates using the RFS were 71.9% for the retrospective group and 73.1% for the prospective group.

Conclusion

By simple and quantitative analyses of the presence of central LNM, the RFS is of great significance when choosing surgical approaches and postoperative individual-based treatment plans, as well as when determining the prognosis of central compartment LNM in patients with PTC.

SPTBN2 Promotes the Progression of Thyroid Cancer by Accelerating G1/S Transition and Inhibiting Apoptosis

Background. Thyroid carcinoma (TC) is an increasingly common malignancy of endocrine organs, and its most frequently encountered histotype is papillary thyroid cancer (PTC). Identifying new potential gene alterations is important for completely elucidating the mechanism of PTC initiation and progression. Thus, we performed whole transcriptome sequence analysis (RNA-seq) on 79 PTC tissue samples and paired adjacent nontumor tissue samples to study the molecular mechanism of TC tumorigenesis and progression further. The results of RNA-seq analysis showed that spectrin beta, nonerythrocytic 2 (SPTBN2), was markedly overexpressed in PTC tissues relative to that in the paired nontumor tissues. Additionally, the analysis results for 502 PTC samples and 58 nontumor thyroid samples from The Cancer Genome Atlas dataset were consistent with our RNA-seq results. However, the molecular mechanisms and function of SPTBN2 in TC progression remain unknown. Methods. We examined SPTBN2 gene expression in 48 papillary thyroid tumor tissues and paired adjacent normal thyroid tissues by using qRT-PCR. SPTBN2 expression in the TC cell lines was silenced by small interfering RNA. Then, the transfected TC cells were used to investigate the in vitro function of SPTBN2. Result. The expression of SPTBN2 was significantly upregulated in our RNA-seq cohort, our local validated cohort, and TCGA RNA-seq cohort. The results of the in vitro experiment revealed that in TC cell lines, SPTBN2 downregulation considerably suppressed tumor cell proliferation, the cell cycle, migration, colony formation, and invasion and induced cell apoptosis. Furthermore, the protein levels of CCNE2, CDK2, CDK4, and Bcl-2 were downregulated, and those of P21, Bax, cleaved caspase-8, and cleaved caspase-3 had increased in transfected TC cells relative to in control TC cells. Conclusion. The downregulation of SPTBN2 caused apoptosis and retarded G1/S cell cycle transition in TC cells. Thus, SPTBN2 may be a good candidate gene for TC diagnosis and therapy.

Validation of Ultrasound Risk Stratification Systems for Cervical Lymph Node Metastasis in Patients with Thyroid Cancer

Simple Summary

Ultrasound (US) malignancy risk stratification systems (RSS) for cervical lymph nodes (LNs) have not been fully established in patients with thyroid cancer. In this study, we assessed the malignancy risks of each US feature and risk category from the Korean Society of Thyroid Radiology (KSThR) and the European Thyroid Association (ETA). Both systems effectively classified malignancy risks; however, 15.1% of LNs were unclassifiable in ETA RSS. Suspicious US features of hyperechogenicity, cystic change, echogenic foci, and abnormal vascularity were independently associated with metastasis. When the primary tumor characteristics were assessed, tumor multiplicity was associated with metastasis in the indeterminate LN group. We refined this system and proposed an RSS based on the KSThR system for cervical LNs in patients with thyroid cancer.

Abstract

A malignancy risk stratification system (RSS) for cervical lymph nodes (LNs) has not been fully established. This study aimed to validate the current RSS for the diagnosis of cervical LN metastasis in thyroid cancer. In total, 346 LNs from 282 consecutive patients between December 2006 and June 2015 were included. We determined the malignancy risk of each ultrasound (US) feature and performed univariable and multivariable logistic regression analyses. Each risk category from the Korean Society of Thyroid Radiology (KSThR) and the European Thyroid Association (ETA) was applied to calculate malignancy risks. The effects of size, number of suspicious features, and primary tumor characteristics were analyzed to refine the current RSS. Suspicious features including echogenic foci, cystic change, hyperechogenicity, and abnormal vascularity were independently predictive of malignancy (p ≤ 0.045). The malignancy risks of probably benign, indeterminate, and suspicious categories were 2.2–2.5%, 26.8–29.0%, and 85.8–87.4%, respectively, according to the KSThR and ETA criteria. According to the ETA criteria, 15.1% of LNs were unclassifiable. In indeterminate LNs, multiplicity of the primary tumor was significantly associated with malignancy (odds ratio, 6.53; p = 0.004). We refined the KSThR system and proposed a US RSS for LNs in patients with thyroid cancer.

Utility and significance of clinical risk factor scoring model in predicting central compartment lymph node metastasis (CLNM) in patients with papillary thyroid cancer (PTC)

Objectives

To establish and discuss the significance of a clinical risk factor scoring model in predicting central compartment lymph node metastasis (CLNM) (level VI) in patients with papillary thyroid cancer (PTC).

Methods

A retrospective analysis was performed on 412 patients who underwent surgical treatment for PTC who were admitted to the Second Hospital of Hebei Medical University between July 2016 and May 2017, with the patients being divided into a CLNM group and a non-metastasis (NM) group. Risk factors such as sex, age, tumor diameter, capsular invasion, multifocality, and tumor location were recorded for scoring via maximum likelihood estimation (MLE)-based discriminant analysis. The scoring model was used for prospective analysis of CLNM in another 104 patients. Besides, the discriminant function that was developed using the risk factors based on the retrospective data derived from the 412 patients was evaluated by plugging the retrospective data in for specified variables, with a higher score indicating a greater risk of developing CLNM. Clinical diagnosis of CLNM was based on postoperative paraffin section pathology, which was adopted as the criterion to assess discriminative accuracy in the prospective and retrospective groups.

Results

The discriminative accuracy of the scoring model was 71.8% in the retrospective group and 72.2% in the prospective group.

Conclusions

The scoring model enables simplified, quantitative analysis of CLNM in PTC patients. The scoring model has clinical significance in that it provides a basis for the choice of operation, personalized postoperative treatment, and prognosis of PTC.

Outcomes of nonsuspicious contralateral nodules with active surveillance after lobectomy in patients with papillary thyroid carcinoma

OBJECTIVE

To observe the outcomes of nonsuspicious contralateral nodules with active surveillance in patients with papillary thyroid carcinoma (PTC).

METHODS

4pt?>Consecutive patients who underwent lobectomy for PTC were retrospectively reviewed. Patients with one or more nodules with nonsuspicious ultrasonography (US) features in the contralateral lobe were included.

RESULTS

Two hundred and eighty-three patients were included. All patients underwent thyroid lobectomy with ipsilateral prophylactic central neck dissection. A total of 123 patients (43.5%) were classified as ATA low-risk, and 160 patients (56.5%) were classified as intermediate-risk. The median size of the contralateral nodules was 3 mm (range, 2 to 16 mm). After a period of follow-up, the median size change of contralateral nodules was 0 mm (range, -7 to 8 mm). Eight patients (2.8%) had nodule growth >3 mm, 223 patients (78.8%) had stable or decreased nodules, and 52 patients (18.4%) had no detectable nodules. Nodules in 24 patients had suspicious US features, 16 of which were diagnosed with PTMC by either cytology after FNA (in 7 patients) or histopathology after completion thyroidectomy (in 9 patients). Another four patients received completion thyroidectomy for ipsilateral cervical lymph node metastasis. The 5-year residual lobe recurrence (RLR) rate and recurrence-free survival (RFS) rate were 7.4% and 89.8%, respectively. Multivariate analysis showed that multifocality and ATA intermediate-risk were independent predictors for RLR (HR4.083, 95%CI 1.480-11.261, P = 0.007; HR 6.045, 95%CI 1.370-26.662, P = 0.017, respectively) and RFS (HR 5.240, 95%CI 2.114-12.991, P < 0.001; HR 5.223, 95%CI 1.353-17.765, P = 0.008, respectively).

CONCLUSIONS

Active surveillance for nonsuspicious contralateral nodules in patients with low-risk and selected intermediate-risk PTC is safe. Multifocality and ATA intermediate-risk are predicters for recurrence. Early detection and salvage surgery are effective.

Does Multifocal Papillary Thyroid Microcarcinoma With a Total Tumor Diameter >1 cm Indicate Poor Biological Behavior? The Evidence is Insufficient

OBJECTIVE

Multifocal cancer is common in papillary thyroid microcarcinoma (PTMC). Our aim was to investigate the correlation between multifocal PTMC, total tumor diameter (TTD), and clinicopathologic features.

METHODS

In total, 206 patients were included and grouped as stage cT1a or cT1b. The primary tumor diameter and TTD (the sum of the maximal diameter of each focus) were calculated. These patients were further subgrouped as TTD ≤1 cm or 1 cm < TTD ≤ 2 cm. The relationships of clinicopathological features between these groups were analyzed.

RESULTS

Multifocal cancer was more likely to occur with stage cT1a than stage cT1b (P = .028). Stage cT1b papillary thyroid carcinoma was more prone to central lymph node metastasis (CLNM) and capsular invasion than stage cT1a. There was no difference in clinicopathological factors, such as sex, age, CLNM, number of CLNMs, capsular invasion, BRAF mutation, or recurrence between the multifocal PTMC and TTD >1 cm and primary tumor diameter + TTD ≤1 cm groups. Comparing stage cT1a and cT1b tumors with a 1 cm < TTD ≤ 2 cm using a multivariate analysis, stage cT1b tumors were more prone to capsular invasion than stage cT1a tumors, with an odds ratio of 19.013 (95% confidence interval, 2.295-157.478), but there was no significant correlation with CLNM.

CONCLUSION

Stage cT1b tumors are more prone to capsular invasion and CLNM than than stage cT1a tumors. For multifocal PTMC, calculating the TTD to evaluate adverse biological behavior is insufficient and limited, and further research is needed.

Risk Factors for Contralateral Occult Carcinoma in Patients With Unilateral Papillary Thyroid Carcinoma: A Retrospective Study and Meta-Analysis

BACKGROUND

Bilateral lesions are common in papillary thyroid carcinoma (PTC). For patients with unilateral PTC, occult carcinoma that is not detected preoperatively, but pathologically after surgery, might remain in the contralateral lobe. In this situation, inadequate surgical extent could cause relapse and even lead to re-operation. Here, we explore the frequency and investigate the risk factors of contralateral occult PTC in unilateral PTC through a retrospective study conducted by our team and published articles online, respectively.

METHODS

We collected the patients' clinical data in our hospital, whose cancer was determined to be confined to the unilateral lobe by preoperative image examination (N = 204). These patients underwent initially total or near-total thyroidectomy and included their clinical data in the meta-analysis. We searched related literature in the PubMed, Embase, MEDLINE, Cochrane, and Web of Science databases until December 7, 2020, in order to perform a meta-analysis. The relevant articles were examined and the eligible studies were included to assess the association between clinicopathologic factors and contralateral occult PTC.

RESULTS

The meta-analysis included nine studies (involving 4347 patients). Of these, eight studies were from the databases, and one study was our retrospective data. The meta-analysis showed that the prevalence of contralateral occult PTC was 26.6% in all patients. A tumor size > 1 cm, ipsilateral multifocality, contralateral benign nodule, and central lymph node metastasis were significantly associated with contralateral occult PTC. In contrast, sex, age, ETE, capsular invasion, BRAF mutation, Hashimoto thyroiditis, and lateral lymph node metastasis were insignificantly associated with contralateral occult PTC.

CONCLUSION

The meta-analysis identified a tumor size > 1 cm, ipsilateral multifocality, contralateral benign nodule, and CLNM as being significant risk factors for contralateral occult PTC. These findings may guide the extent of surgery in unilateral PTC patients.

Influence of Tumor Number on Clinicopathologic Features and Outcomes of Patients With Papillary Thyroid Carcinoma

OBJECTIVES

The purpose of this study was to investigate the significance of tumor number on clinicopathologic factors and outcomes of patients with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively analyzed 667 patients with PTC. We compared clinicopathologic features of patients with a different tumor number. Cox proportional hazards model was used to analyze risk factors of recurrence.

RESULTS

In papillary thyroid microcarcinoma (PTMC), the increase in the number of tumor foci was related to a higher risk of minimal extrathyroidal extension (ETE) and lymphovascular invasion (P < .05). Patients with PTMC with four or more foci had a significantly higher risk of central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) than patients with solitary tumors (P < .05). Patients with macro-PTC with four or more foci and with three foci had a higher risk of gross ETE and lymphovascular invasion than patients with solitary tumors (P < .05). The increase in the tumor number was related to a higher risk of CLNM in macro-PTC (P < .05). The number of foci was the independent predictor of recurrence in patients with macro-PTC (P < .05).

CONCLUSIONS

An increase in the number of tumors was associated with an increased risk of aggressive clinicopathologic features in PTMC and macro-PTC. The number of tumor foci could influence risk of recurrence in macro-PTC.

Hemithyroidectomy for Thyroid Cancer: A Review

Thyroid cancer incidence is on the rise; however, fortunately, the death rate is stable. Most persons with well-differentiated thyroid cancer have a low risk of recurrence at the time of diagnosis and can expect a normal life expectancy. Over the last two decades, guidelines have recommended less aggressive therapy for low-risk cancer and a more personalized approach to treatment of thyroid cancer overall. The American Thyroid Association (ATA) and National Comprehensive Cancer Network (NCCN) thyroid cancer guidelines recommend hemithyroidectomy as an acceptable surgical treatment option for low-risk thyroid cancer. Given this change in treatment paradigms, an increasing number of people are undergoing hemithyroidectomy rather than total or near-total thyroidectomy as their primary surgical treatment of thyroid cancer. The postoperative follow-up of hemithyroidectomy patients differs from those who have undergone total or near-total thyroidectomy, and the long-term monitoring with imaging and biomarkers can also be different. This article reviews indications for hemithyroidectomy, as well as postoperative considerations and management recommendations for those who have undergone hemithyroidectomy.

Predictive factors of lateral lymph node metastasis in conventional papillary thyroid carcinoma

BACKGROUND

Lymph node metastasis (LNM) has been a significant predictor for local recurrence and distant metastasis in papillary thyroid carcinoma (PTC). However, the clinical predictors for conventional papillary thyroid carcinoma (CPTC) with lateral lymph node metastasis (LLNM) have yet to be established. Our work aimed to effectively identify the risk factors of LLNM in CPTC, helping surgeons to devise better individualized therapy strategies.

METHODS

We retrospectively analyzed 652 patients who were diagnosed with CPTC in the Department of General Surgery at Guangdong Provincial People's Hospital between October 2015 and June 2019. Univariate and multivariate logistic regression was used to analyze the correlation between clinicopathological characteristics and the LLNM of CPTC.

RESULTS

The incidence of LLNM in CPTC was 29.75% (194 of 652 patients). Univariate analysis found that LLNM was significantly associated with gender, age, number of central lymph nodes (CLNs), primary tumor location, multifocality, maximum tumor diameter, and BRAF V600E mutation. Independent risk factors for LLNM were multifocality (P=0.017, OR =4.325, 95% CI: 1.298-14.408), maximum tumor diameter (P<0.001, OR =4.076, 95% CI: 1.945-8.540), primary tumor location (P=0.037, OR =2.127, 95% CI: 1.046-4.328), number of CLNs (P<0.001, OR =8.604, 95% CI: 3.630-20.390), and BRAF V600E mutation (P=0.001, OR =3.913, 95% CI: 1.803-8.496) by multivariate analysis.

CONCLUSIONS

LLNM in CPTC was related to the large volume of central lymph node metastasis (CLNM), tumor located in the upper lobe, multifocality, tumor diameter >2 cm, and BRAF V600E mutation-negative, which should be considered when examining patients with suspected metastasis in the lateral compartment.

Thyroid cancer and thyroid autoimmune disease: A review of molecular aspects and clinical outcomes

Thyroid cancer (TC) is the most prevalent malignant neoplasm that affects the endocrine system. Hashimoto's thyroiditis (HT), also known as chronic lymphocytic thyroiditis, is the most common autoimmune thyroid disease (AITD) that, together with Graves' disease (GD), represent the main autoimmune diseases that affect the thyroid gland. Some studies suggest a greater risk of AITD and the development of TC, while others, investigate its relationship with TC progression and patient prognosis. In this review, we have analyzed published data on the molecular aspects related to the association between AITD and TC, addressing their influence on TC progression, diagnosis, and prognosis of the patients. MEDLINE database (PubMed) platform was used as a search engine and the original articles related to the topic were selected using the keywords combination "thyroid cancer and Hashimoto thyroiditis" or "thyroid carcinoma and thyroid autoimmune disease". After the selection, we categorized the main findings of the papers into four topics: antitumor immunity, tumor progression, diagnosis, and prognosis. Although most of the studies have pointed out the presence of AITD as a factor that increases the risk of TC, few molecular mechanisms to support this conclusion have been described. Additionally, little information is available to explain, pathophysiologically, the effects of autoimmunity in TC diagnosis, progression, and prognosis.

Proto-oncogene RTL4 promotes tumorigenesis and invasiveness of papillary thyroid cancer

BACKGROUND

Although the prognosis of papillary thyroid carcinoma (PTC) is good, its widespread prevalence still degrades the quality of life of tens of thousands of patients. PTC can even be life-threatening as a result of its aggressiveness and metastasis.

METHODS

Using complete transcriptome sequence analysis, cutting-edge research has revealed many tumor-associated genes. These related genes help us better understand the tumorigenesis and progression of PTC. We discovered that retrotransposon Gag like 4 (RTL4) is a novel potential PTC-associated gene. By Quantitative real-time polymerase chain reaction (qRT-PCR), we observed an obvious upregulation of RTL4 in PTC tissue. And, we validated the expression characteristics of RTL4 using data from the Cancer Genome Atlas (TCGA). Furthermore, we down-regulated RTL4 expression levels in relevant cell lines and studied the biological function of the RTL4 line in PTC by cell proliferation, colony formation, migration and invasion assays.

RESULTS

In the present study, high expression of RTL4 suggested lymph node metastasis (P = 0.028) and was associated with the pathological type (P = 0.001). RTL4 had the validity of distinguishing PTC tissues and normal tissues showed an AUC of 87.53% for the TCGA data set. The downregulation of RTL4 in the PTC cell lines distinctly inhibited cell colony formation, proliferation, migration, and invasion.

CONCLUSIONS

The result revealed RTL4 is closely related to the occurrence and development of PTC. RTL4 may participate in the HOTAIR-miR-206-ZCCHC16 ceRNA regulatory network and be regulated and play a role in the ceRNA regulatory network. It may be used as a target or indicator for the treatment and prognosis of PTC.

Total tumor diameter: the neglected value in papillary thyroid microcarcinoma

BACKGROUND

Tumor multifocality is not uncommon in papillary thyroid carcinoma (PTC), especially in micro-PTC. However, assessing the size of the largest tumor may underestimate effect of additional foci. We aimed to investigate the effect of total tumor diameter (TTD) on clinicopathological features of micro-PTC.

METHODS

Data from 442 patients who underwent thyroidectomy with cervical lymph node dissection for PTC were retrospectively analyzed. Patients were classified into subgroups according to multifocality and TTD. The relationships of clinicopathological features among these groups were analyzed.

RESULTS

Multifocality was observed in 119 patients (26.9%). TTD > 1 cm and presence of extrathyroidal extension (ETE) were significantly higher in multifocal tumors compared to unifocal tumor (P < 0.001, P = 0.016, respectively). When comparing multifocal micro-PTC with TTD > 1 cm to those with unifocal micro-PTC or multifocal micro-PTC with TTD ≤ 1 cm, the proportions of cases with ETE, central lymph node metastasis (CLNM), and lateral lymph node metastasis (LLNM) were significantly higher (all P < 0.05). There was no significant difference in terms of these parameters between multifocal micro-PTC with TTD > 1 cm and macro-PTC or multifocal macro-PTC. The risk of CLNM was 2.056 (P = 0.044) times higher in multifocal micro-PTC with TTD > 1 cm than in unifocal micro-PTC.

CONCLUSION

For multifocal micro-PTC, TTD can better assess the aggressiveness of the tumor. Multifocal micro-PTC with TTD > 1 cm was more aggressive than unifocal micro-PTC or multifocal micro-PTC with TTD ≤ 1 cm.

Management of Clinically Solitary Papillary Thyroid Carcinoma Patients According to Risk-Scoring Model for Contralateral Occult Carcinoma

OBJECTIVE

The aim of this study was to investigate risk factors of occult carcinoma in clinically solitary papillary thyroid carcinoma (PTC) patients, and to put emphasis on the predictive value of risk-scoring model to determine the optimal scope of surgery.

METHODS

A total of 573 clinically solitary PTC patients who underwent total thyroidectomy (TT) from two hospitals were retrospectively analyzed. Clinicopathological features were collected, univariate and multivariate analyses were performed to determine risk factors of occult carcinoma. The Cox proportional hazards model was used to analyze the risk factors of recurrence. A scoring model was constructed according to independent risk factors of contralateral occult carcinoma.

RESULTS

19.2% of clinically solitary PTC patients had occult carcinoma, among which 3.7% patients had ipsilateral occult carcinoma and 15.5% patients had contralateral occult carcinoma. Factors such as male, the presence of benign nodule, and vascular invasion increase the risk of ipsilateral occult carcinoma. Tumor size >1 cm, the presence of benign nodule, extrathyroidal extension, central lymph node metastasis, lateral lymph node metastasis are independent predictors of contralateral occult carcinoma. Contralateral occult carcinoma is the independent predictor of recurrence. A 10-point risk-scoring model was established to predict the contralateral occult carcinoma in clinically solitary PTC patients.

CONCLUSION

Lobectomy is sufficient for clinically solitary PTC patients with risk factors of ipsilateral occult carcinoma. For clinically solitary PTC patients with score ≥4, careful preoperative evaluations are required to rule out the contralateral occult carcinoma. Even if contralateral occult carcinoma is not detected preoperatively, TT is recommended for high-risk patients.

Altered expression of DLG1-AS1 distinguished papillary thyroid carcinoma from benign thyroid nodules

BACKGROUND

Benign thyroid nodules (BTN) are frequently diagnosed as papillary thyroid carcinoma (PTC), leading to unnecessary treatment. We found that plasma lncRNA DLG1-AS1 was upregulated in PTC patients but not in BTN patients and healthy controls.

METHODS

In this study DLG1-AS1 and miR-199a-3p in plasma of both PTC patients and BTN patients were detected by qPCR. ROC curve analysis was performed for diagnostic analysis. Overexpression experiments were performed to analyze the interaction between DLG1-AS1 and miR-199a-3p. CCK-8 assay was performed to analyze cell proliferation.

RESULTS

In this study, upregulation of DLG1-AS1 distinguished PTC patients from BTN patients and healthy controls. Plasma miR-199a-3p was downregulated in PTC patients compared with healthy controls and BTN patients. Plasma levels of miR-199a-3p were inversely correlated in PTC patients, but not in BTN patients and healthy controls. miR-199a-3p overexpression failed to significantly affect DLG1-AS1, while DLG1-AS1 overexpression resulted in downregulated miR-199a-3p, In addition, DLG1-AS1 overexpression promoted the proliferation of PTC cells. miR-199a-3p overexpression played an opposite role and attenuated the effects of DLG1-AS1 overexpression.

CONCLUSIONS

Therefore, DLG1-AS1 may promote PTC by downregulating miR-199a-3p.

Should multifocality be an indication for completion thyroidectomy in papillary thyroid carcinoma?

BACKGROUND

Multifocality in papillary thyroid carcinoma is common. The aim of this study is to determine whether patients with multifocal disease, treated with lobectomy alone, have an increased risk of contralateral lobe papillary thyroid carcinoma, regional recurrence, and poorer survival.

METHODS

After institutional review board approval, papillary thyroid carcinoma patients managed from 1986 to 2015 with lobectomy alone were identified from an institutional database. Papillary thyroid carcinoma patients with pT3 to T4 classification, nodal disease, or distant metastases were excluded. After excluding 40 patients who underwent an immediate completion thyroidectomy, 849 were included in the analysis; 619 (72.9%) had unifocal disease and 230 (27.1%) had multifocal disease. Contralateral lobe papillary thyroid carcinoma-free probability, regional recurrence-free probability, disease-specific survival, and overall survival were calculated using the Kaplan-Meier method.

RESULTS

With a median follow-up of 58 months, unifocal disease and multifocal disease patients had similar rates of contralateral lobe papillary thyroid carcinoma, regional recurrence, and overall survival (10-year contralateral lobe papillary thyroid carcinoma-free probability 98.6% vs 97.8%; regional recurrence-free probability 99.5% vs 99.4%; overall survival 91.6% vs 93.1%, respectively). There were no disease-related deaths.

CONCLUSION

Select multifocal disease patients, managed with lobectomy alone, have rates of contralateral lobe papillary thyroid carcinoma, regional recurrence, and overall survival comparable to unifocal disease patients. Multifocal disease should not be an indication for completion thyroidectomy.

CITED1 gene promotes proliferation, migration and invasion in papillary thyroid cancer

Thyroid cancer is the most common malignancy of the endocrine organs. In order to further understand the tumorigenesis and progression of papillary thyroid carcinoma (PTC), the present study performed whole transcriptome sequence analysis. It was found that Cbp/p300-interacting transactivators with glutamic acid [E] and aspartic acid [D]-rich C-terminal domain 1 (CITED1) was a novel potential PTC-associated gene in thyroid cancer. The expression level and clinicopathological features of CITED1 were then assessed in The Cancer Genome Atlas (TCGA) database. The expression of CITED1 was knocked down and the biological function of CITED1 in PTC cell lines was examined. The results showed that upregulated CITED1 was associated with lymph node metastasis (P=0.006) and clinical stage (P=0.003). In order to differentiate PTC tissues and normal tissues, an area under the curve was constructed of a receiver operating characteristic of 91.3% for the TCGA cohort and 85.3% for a validated cohort. The downregulated expression of CITED1 significantly inhibited cell proliferation, colony formation, migration and invasion in the PTC cell lines. The present study demonstrated that CITED1 is important in the tumorigenesis and metastasis of PTC and may be a potential therapeutic target in PTC.

Risk factors of central lymph node metastasis in papillary thyroid carcinoma: A retrospective cohort study

OBJECTIVE

The aim of this study was to explore the risk factors that were associated with central lymph node metastases (CLNM) in papillary thyroid carcinoma (PTC) patients.

METHODS

A total of 180 patients with PTC who underwent surgery in our hospital between January 2014 and December 2016 were identified retrospectively. The relationship between clinicopathological factors and CLNM were analyzed by univariate and multivariate logistic regression.

RESULTS

The incidence of CLNM was 67.8% (122/180) in PTC patients. Univariate analysis showed that multifocality (p = 0.002), HT (p < 0.001) and LVI (p < 0.001) were significant associated with CLNM. No significant associations were found between factors and CLNM, including age, gender, tumor size and ETE. Multivariate logistic regression analysis showed that multifocality (p = 0.011), HT (p < 0.001) and LVI (p < 0.001) were independent predictors of CLNM in PTC patients.

CONCLUSIONS

Our study identified several independent risk factors predicting CLNM in PTC patients, such as multifocality, HT and LVI. The CLNM is very common in PTC patients, and routine prophylactic central neck dissection (PCND) may recommended in PTC patients with those risk factors of CLNM.

Independent predictors and lymph node metastasis characteristics of multifocal papillary thyroid cancer

The multifocal papillary thyroid cancer (PTC), with more aggressive and poorer prognosis, is not rare in papillary histotype. Few studies evaluated risk factors and lymph node metastasis in multifocal PTC. The aim of this present study focusing on risk factors and lymph node metastasis characteristics in multifocal PTC was excepted to assist clinical decisions regarding surgery.It was a retrospective study. The 1249 consecutive patients with PTC were reviewed. Of these, 570 patients who met the criteria were selected: 285 with solitary papillary thyroid cancer and 285 with multifocal PTC. The risk factors and lymph node metastasis in multifocal PTC were investigated by univariate and multivariate analysis.Multifocal PTC showed a higher positive rate of capsular invasion, extrathyroidal extension, tumor size >10 mm, pathological T classification, N+ stage, local recurrence, and radioactive iodine ablation (RAI). Capsular invasion (hazard ratio [HR], 1.589; 95% confidence interval [CI],1.352-1.984), advanced pathological T classification (HR, 3.582; 95% CI, 2.184-5.870), and pathological N+ stage (HR, 1.872; 95% CI, 1.278-2.742) were related to increased risk of multifocality and there was a significant increased HR for central neck compartment involvement in male sex (HR, 2.694; 95% CI, 1.740-4.169), advanced pathological T classification (HR, 2.403; 95% CI, 1.479-3.907) and multifocality (HR, 1.988; 95% CI, 1.361-2.906).There is a significant association between capsular invasion, advanced pathological T classification, N+ stage, and multifocal PTC. Total thyroidectomy plus prophylactic bilateral central lymph node dissection should be recommended during surgery due to a stronger predilection for level VI lymph node metastasis in multifocal PTC.

Gender-Specific Risk of Central Compartment Lymph Node Metastasis in Papillary Thyroid Carcinoma

Our aim was to evaluate the impact of gender on the predictive factors of central compartment lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC). A retrospective study of 590 patients treated for PTC was performed. Univariate and multivariate analyses showed that gender (female; P = 0.001), age (≥45 y; P < 0.001), tumor size (>1 cm; P < 0.001), and multifocality (P = 0.004) were independent predictive factors of CLNM in PTC patients. Patients were divided into male group (n = 152) and female group (n = 438). Age (≥45 y; P = 0.001), T4 (P = 0.006) and multifocality (P = 0.024) were independent predictive risk factors of CLNM in male patients. As for female patients, age (≥45 y; P < 0.001), tumor size (>1 cm; P < 0.001), multifocality (P = 0.002), and microcalcification (P = 0.027) were independently correlated with CLNM. The sensitivity of the multivariate model for predicting CLNM in male patients was 64.9%, specificity was 82.9%, and area under the ROC curve (AUC) was 0.764. As for female patients, the sensitivity was 55.7%, specificity was 77.9%, and AUC was 0.73. This study showed that the predictive factors of CLNM indeed varied according to gender. To have a more accurate evaluation of CLNM, different predictive systems should be used for male and female patients.

Clinical predictors of lymph node metastasis and survival rate in papillary thyroid microcarcinoma: analysis of 3607 patients at a single institution

BACKGROUND

The treatment of papillary thyroid microcarcinoma (PTMC) patients is controversial, as PTMC is often found incidentally and its prognosis is quite good. Because lymph node metastasis (LNM) is one of the main predictors of recurrence and impacts the survival rate of PTMC patients, this study aims to retrospectively identify the clinical factors that increase the risk of LNM and/or recurrence and can then be used to separate clinically unfavorable PTMCs from the rest and to help guide their treatment accordingly.

METHODS

Clinical and pathologic data were collected from 3607 patients diagnosed with PTMC at Shanghai Renji Hospital between 2005 and 2015. Univariate and multivariate analyses were performed to identify the clinical predictors of LNM and survival rates were calculated by using the Kaplan-Meier method.

RESULTS

Our univariate and multivariate analyses show that age of <45 y (P < 0.01), gender of male (P < 0.01), tumor diameter >0.7 cm (P < 0.01), and multifocality (P < 0.01) significantly increase the risk of central LNM. However, clinical factors, such as LNM, age, gender, multifocality, and operation range, do not affect the 10-y disease-free survival rate (P > 0.05).

CONCLUSIONS

Clinical factors, such as gender of male, age of <45 y, multifocality, and tumor size >0.7 cm, suggest a higher risk of LNM; however, they do not affect PTMC patients' 10-y disease-free survival rate. We recommend ipsilateral lobectomy to PTMC patients. For PTMC patients with higher LNM risk, preoperative central and lateral cervical lymph node imaging examination should be emphasized, and lymph node dissection is recommended. The range of dissection should be determined based on the imaging results.

Association of tumor size and focality with recurrence/persistence in papillary thyroid cancer patients treated with total thyroidectomy along with radioactive-iodine ablation and TSH suppression

Locoregional recurrence is common in papillary thyroid cancer PTC and an optimal surgical treatment with respect to the multifocal nature of the disease stays controversial. It is a retrospective analytical study design. 209 diagnosed PTCs managed at our institute were grouped into macro-PTC with a size of dominant focus >1 cm (unifocal n = 106 and multifocal n = 64) and micro-PTMC if size of all foci was <1 cm; (unifocal n = 16 and multifocal PTMC n = 23). The primary endpoint is recurrence and tumor free survival in each of the four groups. Secondary endpoint is an assessment of a benefit of completion total thyroidectomy in terms of assignment of true focal status to an individual's PTC. The median follow-up was 4.1 years. Upon completion thyroidectomy, the tumor focality changed to multifocal in 31.4% of macro-PTC and 60% of micro-PTMC. Multifocality was an independent risk factor for recurrence, OR 2.41 for macro (CI 1.14-5.11), and 3.48 for micro-multifocal PTMC (CI 1.19-10.2). Disease free survival patterns on Kaplan-Meier's plots were alike for micro- and macro-unifocal groups, and similarly stayed comparable among the two multifocal groups. Our analysis showed that tumor multifocality rather than size is the significant factor determining prognosis; hence, total thyroidectomy is indicated for an optimal assessment of true focality in micro-PTC.

Therapeutic Outcomes of Patients with Multifocal Papillary Thyroid Microcarcinomas and Larger Tumors

A retrospective review of 626 patients with multifocal papillary thyroid carcinoma (PTC) including 147 patients (23.5%) with multifocal papillary thyroid microcarcinoma (PTMC) from a total of 2,536 patients with PTC who visited the Chang Gung Medical Center in Linkou, Taiwan, was performed. A comparison of the clinical features between 626 multifocal and 1,910 solitary PTC cases showed that patients in the multifocal PTC group were older and had a smaller mean tumor size, a more advanced tumor-node-metastasis (TNM) stage, and a higher percentage of nonremission status compared to patients in the solitary PTC group. Of the 626 patients with multifocal PTC, the group with larger tumors showed a more advanced TNM stage, a higher percentage of lymph node metastasis and soft tissue invasion, and a higher nonremission rate compared to the multifocal PTMC group. Of the 626 patients with multifocal PTC, 25 patients (4%) died during a mean follow-up period of 7.1 ± 5.3 years. Kaplan-Meier survival curves showed a significantly lower survival rate associated with multifocal PTMC compared to that with solitary PTMC.

Association of multifocality, tumor number, and total tumor diameter with clinicopathological features in papillary thyroid cancer

Tumor multifocality is not an unusual finding in papillary thyroid carcinoma (PTC), but its clinical significance is controversial. In this study, we aimed to evaluate impact of multifocality, tumor number, and total tumor diameter on clinicopathological features of PTC. Medical records of 912 patients who underwent thyroidectomy and diagnosed with PTC were reviewed retrospectively. Patients were grouped into four according to number of tumoral foci: N1 (1 focus), N2 (2 foci), N3 (3 foci), and N4 (≥4 foci). The diameter of the largest tumor was considered the primary tumor diameter (PTD), and total tumor diameter (TTD) was calculated as the sum of the maximal diameter of each lesion in multicentric tumors. Patients were further classified into subgroups according to PTD and TTD. Multifocal PTC was found in 308 (33.8 %) patients. Capsular invasion, extrathyroidal extension, and lymph node metastasis were significantly higher in patients with multifocal tumors compared to patients with unifocal PTC. As the number of tumor increased, extrathyroidal extension and lymph node metastasis also increased (p = 0.034 and p = 0.004, respectively). The risk of lymph node metastasis was 2.287 (OR = 2.287, p = 0.036) times higher in N3 and 3.449 (OR = 3.449, p = 0.001) times higher in N4 compared to N1. Capsular invasion, extrathyroidal extension, and lymph node metastasis were significantly higher in multifocal patients with PTD ≤10 mm and TTD >10 mm than unifocal patients with tumor diameter ≤10 mm (p < 0.001, p < 0.001 and p = 0.001, respectively). There was no significant difference in terms of these parameters in multifocal patients with PTD ≤10 mm and TTD >10 mm and unifocal patients with tumor diameter >10 mm. In this study, increased tumor number was associated with higher rates of capsular invasion, extrathyroidal extension, and lymph node metastasis. In a patient with multifocal papillary microcarcinoma, TTD >10 mm confers a similar risk of aggressive histopathological behavior with unifocal PTC greater than 10 mm.

Papillary Thyroid Carcinoma: Association Between Germline DNA Variant Markers and Clinical Parameters

BACKGROUND

Papillary thyroid cancer (PTC) is reported to be highly heritable in epidemiological studies. Genome-wide association studies (GWAS) have uncovered several variants associated with PTC predisposition. It remains unknown whether these variants might contribute to better clinical stratification of PTC patients.

METHODS

In order to assess the usefulness of germline genetic analyses in the management of PTC patients, the genotypes of five variants (rs965513, rs944289, rs116909374, rs2439302, and rs966423) were determined in 1216 PTC patients and 1416 controls. Additionally, the expression of seven genes located close to GWAS variants (PTCSC3, MBIP, NKX2-1, FOXE1, DIRC3, PTCSC2, and NRG1) were measured in 73 PTC paired tumor/normal tissues, respectively. Next, the association was analyzed between the genotypes of the germline variants and the levels of gene expression with clinical/pathological features such as age, sex, TNM staging, multifocality status, extrathyroidal expansion, and MACIS score.

RESULTS

The risk allele of rs965513 was associated with larger tumor size (p = 0.025) and extrathyroidal expansion (odd ratio [OR] = 1.29, p = 0.045). The variant rs2439302 showed association with lymph node metastasis (OR = 1.24, p = 0.016), and multifocality status of the tumor (OR = 1.24, p = 0.012). The expression of MBIP was associated with T stage (p = 0.010). MBIP and PTCSC3 displayed lower expression in PTC tissue in males than in females (p = 0.025 and p = 0.036, respectively). NKX2-1 displayed lower expression in patients with N1 stage (p = 0.040).

CONCLUSIONS

The studied germline risk alleles predisposing to PTC were associated with a more aggressive course of the disease reflected by larger tumor diameter, higher multifocality rate, and more advanced N stage at the time of diagnosis. These results show that germline variants not only predispose to PTC but also might impact its clinical course. However, these associations were only moderate, and further large multi-ethnic studies are required to evaluate the usefulness of these germline variants in the clinical stratification of PTC patients.

Detection of Tumor Multifocality Is Important for Prediction of Tumor Recurrence in Papillary Thyroid Microcarcinoma: A Retrospective Study and Meta-Analysis

Background:

The clinicopathological characteristics and conclusive treatment modality for multifocal papillary thyroid microcarcinoma (mPTMC) have not been fully established.

Methods:

A retrospective study, systematic review, and meta-analysis were conducted to elucidate the clinicopathological significance of mPTMC. We investigated the multiplicity of 383 classical papillary thyroid microcarcinomas (PTMCs) and the clinicopathological significance of incidental mPTMCs. Correlation between tumor recurrence and multifocality in PTMCs was evaluated through a systematic review and meta-analysis.

Results:

Tumor multifocality was identified in 103 of 383 PTMCs (26.9%). On linear regression analysis, primary tumor diameter was significantly correlated with tumor number (R²=0.014, p=.021) and supplemental tumor diameter (R²=0.117, p=.023). Of 103 mPTMCs, 61 (59.2%) were non-incidental, with tumor detected on preoperative ultrasonography, and 42 (40.8%) were diagnosed (incidental mPTMCs) on pathological examination. Lymph node metastasis and higher tumor stage were significantly correlated with tumor multifocality. However, there was no difference in nodal metastasis or tumor stage between incidental and non-incidental mPTMCs. On meta-analysis, tumor multifocality was significantly correlated with tumor recurrence in PTMCs (odds ratio, 2.002; 95% confidence interval, 1.475 to 2.719, p<.001).

Conclusions:

Our results show that tumor multifocality in PTMC, regardless of manner of detection, is significantly correlated with aggressive tumor behavior.

Clinical and Pathologic Predictors of Lymph Node Metastasis and Recurrence in Papillary Thyroid Microcarcinoma

BACKGROUND

The treatment for patients with papillary thyroid microcarcinoma (PTMC) is controversial because PTMC is often found incidentally and its prognosis is very good. Lymph node metastasis (LNM) is one of the main predictors of recurrence and survival. This retrospective study aimed to identify clinical and pathologic factors that increase the risk of metastasis or recurrence, in order to isolate clinically unfavorable PTMCs to help guide therapy.

METHODS

Clinical and pathologic data were collected from 273 patients diagnosed with PTMC at The University of Chicago Medical Center between 2000 and 2011. Data points included age, sex, race/ethnicity, tumor size, multifocality, thyroiditis, extrathyroidal extension (ETE), surgical margins, preoperative clinical suspicion of cancer, central/lateral lymph nodes removed and lymph nodes with metastatic carcinoma, treatment, local recurrence, distant recurrence, and survival.

RESULTS

Multivariate logistic regression showed that age <45 years (odds ratio [OR] = 3.565 [confidence interval (CI) 1.137-11.177]), multifocality (OR = 3.556 [CI 1.066-11.855]), and ETE (OR = 4.622 [CI = 1.068-20.011]) significantly increased the risk of central LNM (CLNM). However, sex, size of tumor, thyroiditis, positive margins, and clinical suspicion were not correlated with an increased risk for CLNM. Multivariate logistic regression showed that only ETE (OR = 16.066 [CI 1.850-139.488]) significantly increased the risk of lateral LNM. In the cohort of 202 patients with follow-up data, only six recurred. Median time to recurrence was approximately 12 months (range 3.5-120 months), and median follow-up was 42 months. No patient had distant metastasis, and no patients died.

CONCLUSIONS

PTMC is an indolent disease, but does pose a risk for LNM and local recurrence. More aggressive treatment or more frequent follow-up could be considered for patients with unfavorable features (age <45 years, multifocality, ETE), especially in the setting of involved lymph nodes at the time of surgical resection, as these patients may be at an increased risk for recurrence.

Bilaterality weighs more than unilateral multifocality in predicting prognosis in papillary thyroid cancer

Papillary thyroid cancer (PTC) often presents as multifocal tumor;, however, whether multifocality is associated with poor prognosis remains controversial. The aims of this retrospective study were to identify the characteristics of PTC with multifocal tumors and evaluate the association between the location and prognosis. We reviewed the medical records of 496 patients who underwent total thyroidectomy for PTC. Patients were classified as three groups: N1 (solitary tumor), N2 (2 or more foci within unilateral lobe of thyroid), and N3 (bilateral tumors, at least one tumor focus for each lobe of thyroid). We analyzed the differences of clinicopathologic features and clinical outcomes among the three groups. Cox regression model was used to assess the relation between the different locations of multifocal tumors and prognosis. Although the differences of clinicopathologic features such as the size of tumor, extrathyroidal extension, and cervical lymph node metastasis were not significant among the three groups, the bilateral-multifocality was proved to be an independent risk factor for neck recurrence (hazard ratio (HR) = 4.052, 95 % confidence interval (CI) 2.070-7.933), distant metastasis (HR = 3.860, 95 % CI 1.507-9.884), and cancer death (HR = 7.252, 95 % 2.189-24.025). In addition, extrathyroidal extension (HR = 2.291, 95 % CI 1.185-4.427) and older age >45 years (HR = 6.721, 95 % CI 2.300-19.637) were also significant predictors for neck recurrence and cancer death, respectively. Therefore, bilateral-multifocality as an indicator for more extensive tumor location could be used to assess the risk of recurrence and mortality in PTC. Given the poor prognosis associated with bilateral-multifocality and other risk factors, aggressive therapy and intensive follow-up were recommended for PTC patients with them.

CLINICALLY UNDETECTABLE OCCULT THYROID PAPILLARY CARCINOMA PRESENTING WITH CERVICAL LYMPH NODE METASTASIS

Background

Occult papillary thyroid carcinoma presented as isolated cervical lymphadenopathy without clinical and radiologic findings has been rarely reported.

Case report

A 47 years old female patient admitted to otorhinolaryngology clinic with 4X3 cm sized cervical mass. Physical examination of the patient was noted as a nontender, firm, mobile lymph node at right lateral cervical region. There was no inflammatory or infection disease in the history of patients anamnesis and no abnormal value on laboratory tests. Ultrasound screening of the neck detected a lymph node with suspicious features for malignancy. Head and neck examination was normal and there is no evidence of a tumoral mass or nodule in the thyroid gland. Whole body scan of MRI showed no pathologic sign both in the neck and body. Excisional biopsy was performed and revealed a carcinoma with papillary morphology. Immunohistochemical staining features of the tumor confirmed a papillary carcinoma derived from the thyroid gland. Second look USG of the neck and thyroid was performed but it revealed no tumoral mass. The patient underwent total thyroidectomy with right functional and central lymph node dissection. Histological examination of the thyroid gland showed multicentric 2 mm sized, three foci of papillary carcinoma located in bilateral thyroid lobes and metastatic lymph nodes in the right side of the neck.

Conclusion

A metastatic cervical lymph node can be evidence of a clinically undetected occult papillary thyroid carcinoma. Specific immunohistochemistry staining of specimen may lead to appropriate surgery and progression of carcinoma may be hindered by application of additional RAI therapy.

Multifocal Papillary Thyroid Cancer Increases the Risk of Central Lymph Node Metastasis

BACKGROUND

Papillary thyroid cancer (PTC) is the most common thyroid malignancy, with a strong predilection for lymph node metastasis, most commonly to the central neck compartment (level VI). Few studies have evaluated lymph node metastasis in multifocal PTC, and the role of level VI dissection in the management of PTC remains controversial. This retrospective analysis evaluated the rate of level VI lymph node positivity in multifocal PTC, as compared with unifocal disease, in order to inform surgical decision making better.

METHODS

Patients with PTC who underwent total or hemi-thyroidectomy plus level VI lymph node dissection at the authors' institution between January 2008 and June 2014 were included (N=227). The number and laterality of PTC foci, lymphovascular invasion (LVI), extrathyroidal extension (ETE), and positive/total number of level VI lymph nodes were recorded. Fisher's exact test was used to determine univariate associations, and multivariate analysis was done by logistical regression.

RESULTS

There was an association between the number of PTC foci and level VI node positivity (p<0.001), with an odds ratio (OR) of 2.355 in patients with three or more tumor foci (p=0.026). The OR for central neck metastasis was 1.088 with each additional focus of PTC (p=0.018). The risk of level VI node positivity in the presence of one or two foci was only 19%, with no appreciable difference between one and two foci. This risk increased in the presence of between three and nine foci (38%), and 10 or more foci (88%). Level VI node positivity was associated with ETE (p<0.001), LVI (p<0.001), and size of the largest focus (p<0.001). There was no association between level VI lymph node positivity and male sex (p=0.089), bilaterality (p=0.276), or age (p=0.076).

CONCLUSIONS

There is a significant association between multifocal PTC and level VI lymph node positivity, increasing proportionally with the number of foci. These findings recognize multifocality as a sign of tumor aggressiveness, as evidenced by a higher propensity for lymph node metastasis.

Clinical characteristics and surgical resection of multifocal papillary thyroid carcinoma: 168 cases

PURPOSE

To investigate clinical characteristics and surgical treatment of multifocal papillary thyroid carcinoma.

METHODS

A total of 648 patients diagnosed with papillary thyroid carcinoma were enrolled, 168 with multifocal papillary thyroid carcinoma. Clinicopathological factors including gender, age at diagnosis, family history of thyroid tumor, multiplicity and bilaterality of tumor, extra-thyroidal extension, lymph node involvement and other factors were statistically compared.

RESULTS

The incidence of multifocal papillary thyroid carcinoma was 25.9% and 117 presented with bilateral thyroid gland lesions. In multifocal group, patients had a higher ratio of male subjects, family history of thyroidal tumor, neck lymph node metastasis and extra-thyroidal extension by B-ultrasound. Solitary papillary thyroid carcinoma tended to be with a higher rate of benign goiters. In multifocal group, males with neck lymphadenectasis, ≥ 3 tumor masses or bilaterality of tumors tended to present with larger tumors, a higher incidence of neck lymph node metastasis and extra-thyroidal extension. 164 cases completed the follow-up, 5 died, 1 suspected with lung metastasis and still survived, 6 underwent repeated surgery due to lymph node recurrence at 3-41 months postoperatively and 2 surgically treated with recurrent gland tumor. Overall 1-, 2-, 5-, and 10-year survival rate was 98.2%, 97.4%, 96.5% and 96.5%, respectively.

CONCLUSION

Multifocal papillary thyroid carcinoma is more malignant and highly differentiated than solitary lesions. Total thyroidectomy combined with neck dissection of central compartment could be utilized as standard treatment. Lateral nodular dissection should be considered for the patients with lymph node metastasis.

Ultrasonic features of papillary thyroid microcarcinoma and non-microcarcinoma

The present study analyzed the ultrasonic features of papillary thyroid microcarcinoma (PTMC) and papillary thyroid non-microcarcinoma (non-PTMC) with the aim of improving the diagnostic value of ultrasonography. The ultrasonic features of 328 patients with papillary thyroid carcinoma (PTC), as confirmed by pathology, were retrospectively analyzed. Patients were diagnosed with PTMC if the tumor size was ≤10 mm in diameter or non-PTMC if the tumor size was >10 mm in diameter. The shape, ratio of length/width, boundary, echo, peripheral halo ring, calcification, cystic changes, blood flow, lymph node metastasis and additional accompanying thyroid diseases were compared between the patients with PTMC and non-PTMC. In total, 389 nodules were identified in the 328 patients, including 209 PTMC nodules and 180 non-PTMC nodules. The multifocality rate was 15.9% (52/328). Ultrasound scans detected a total of 371 nodules, while 18 PMTC nodules were missed diagnosed and 57 nodules were misdiagnosed as benign nodules. Statistically significant differences in the boundary, ratio of length/width, cystic changes, blood flow and lymph node metastasis were observed between the PTMC and non-PTMC groups (P<0.05). However, no statistically significant differences were observed with regard to the shape, calcification, peripheral halo rings and additional accompanying thyroid diseases between the two groups (P>0.05). Therefore, ultrasound plays an important role in the diagnosis of PTC, with PTMC and non-PTMC exhibiting different ultrasonic performances.