Differences in the Recurrence and Survival of Patients with Symptomatic and Asymptomatic Papillary Thyroid Carcinoma: An Observational Study of 11,265 Person-Years of Follow-Up

Papillary Thyroid Carcinoma: Correlation Between Molecular and Clinical Features

BACKGROUND

Thyroid cancer is prevalent worldwide, including in China, where its incidence is on the rise. Papillary thyroid carcinoma (PTC) is the predominant subtype. Investigating the relationship between clinical data associated with PTC and gene mutations is crucial for improving detection and treatment.

PATIENTS AND METHODS

We collected samples and associated clinical data from 700 PTC patients at Shanxi Provincial People's Hospital. Using a panel of 57 genes linked to thyroid cancer, we sequenced the samples to determine the mutation frequency of thyroid cancer-associated genes in PTC. We further analyzed the correlation between gene variants and clinical information.

RESULTS

The mean age of patients in this study was 42.5 years. Females predominated, comprising 507 of the total patient population, resulting in a female-to-male ratio of 2.63 (507:193). Tumor distribution revealed 198, 257, and 142 cases on the left, right, and both sides, respectively. Among the 57 thyroid cancer-related genes analyzed, we identified at least one driver gene in 83.6% of patients. Notably, 76.4% had BRAF mutations, mainly BRAFV600E, which constituted 90.9% of all BRAF mutations, with 535 cases exhibiting these mutations. Other significant driver genes included CHEK2 (n = 84), RET (n = 42), PIK3CA (n = 7), and EGFR (n = 7). RET fusions (n = 28) were also identified. Notably, patients under 55 years old exhibit a higher tendency towards advanced N staging, suggesting that younger individuals may be more prone to lymph node metastasis. Additionally, male patients were more likely to have advanced N stages. Importantly, a positive correlation was observed between higher BRAF allele frequencies and more advanced T and N stages. Similarly, correlation analysis revealed that a greater frequency of RET fusions correlated with later T and N stages.

CONCLUSION

This study uncovered several significant insights. Younger PTC patients exhibited a higher propensity for lymph node metastasis. An elevated mutation frequency of BRAF was correlated with a higher occurrence of RET fusions, predisposing individuals to lymph node metastasis and potentially indicating a poorer prognosis.

The Not-So-Good Cancer: Psychosocial Challenges for YA Thyroid Cancer Patients and Survivors and the Creation of a YA Thyroid Cancer Support Group

Thyroid cancer (TC) has been deemed "the good cancer" owing to its slow growth, availability of targeted treatment, and low mortality rates. Inconsistent with this name, survivors of TC have similar or poorer quality of life than individuals with other types of cancer. Furthermore, young adults (YAs; age 18-35) with TC are at risk for additional psychosocial challenges. Support groups have been identified as a mechanism for improving quality of life among other YAs with cancer. A YA TC group is warranted given the unique experiences of TC survivors. Discussion points from a newly developed YA TC support group are reviewed.

Cost-Utility Analysis of Early Detection with Ultrasonography of Differentiated Thyroid Cancer: A Retrospective Study on a Korean Population

BACKGRUOUND

There is debate about ultrasonography screening for thyroid cancer and its cost-effectiveness. This study aimed to evaluate the cost-effectiveness of early screening (ES) versus symptomatic detection (SD) for differentiated thyroid cancer (DTC) in Korea.

METHODS

A Markov decision analysis model was constructed to compare the cost-effectiveness of ES and SD. The model considered direct medical costs, health outcomes, and different diagnostic and treatment pathways. Input data were derived from literature and Korean population studies. Incremental cost-effectiveness ratio (ICER) was calculated. Willingness-to-pay (WTP) threshold was set at USD 100,000 or 20,000 per quality-adjusted life year (QALY) gained. Sensitivity analyses were conducted to address uncertainties of the model's variables.

RESULTS

In a base case scenario with 50 years of follow-up, ES was found to be cost-effective compared to SD, with an ICER of $2,852 per QALY. With WTP set at $100,000, in the case with follow-up less than 10 years, the SD was cost-effective. Sensitivity analysis showed that variables such as lobectomy probability, age, mortality, and utility scores significantly influenced the ICER. Despite variations in costs and other factors, all ICER values remained below the WTP threshold.

CONCLUSION

Findings of this study indicate that ES is a cost-effective strategy for DTC screening in the Korean medical system. Early detection and subsequent lobectomy contribute to the cost-effectiveness of ES, while SD at an advanced stage makes ES more cost-effective. Expected follow-up duration should be considered to determine an optimal strategy for DTC screening.

Correlation analysis of risk factors for cervical lymphatic metastasis in papillary thyroid carcinoma

OBJECTIVE

This study aims to identify and analyze the risk factors associated with Cervical Lymph Node Metastasis (CNM) in Papillary Thyroid Carcinoma (PTC) patients.

METHODS

We conducted a retrospective study involving the clinicopathological data of 2384 PTC patients admitted to our hospital between January 2016 and December 2020. All relevant data were statistically processed and analyzed.

RESULTS

The related risk factors for Central Lymph Node Metastasis (CLNM) were gender (male), age (≤ 30 years old), tumor lesion size (> 0.855 cm), and multifocal tumor foci. The ROC curve revealed that the critical value for predicting CLNM based on tumor lesion size was 0.855 (sensitivity = 57.9%, specificity = 69%, AUC = 0.269, and P < 0.05). Lateral Lymph Node Metastasis (LLNM) was positively correlated with tumor diameter. Specifically, the LLNM rate increased with the tumor diameter. LLNM occurrence was significantly higher in zones II, III, and IV than in zones I and V. Although the BRAF gene mutation detection assay has certain clinical benefits in diagnosing PTC and LLNM, no statistically significant difference was found in its relationship with central and lateral neck lymph node metastases (P = 0.741).

CONCLUSION

Our findings revealed that CLNM is associated with gender (male), age (≤ 30 years old), tumor lesion size (> 0.855 cm), and multiple tumor lesions in PTC patients. Central Lymph Node Dissection (CLND) is recommended for patients with these risk factors. On the other hand, preoperative ultrasound examination, fine-needle pathological examination, and genetic testing should be used to determine whether Lateral Cervical Lymph Node Dissection (LLND) is needed.

Factors influencing extrathyroidal extension of papillary thyroid cancer and evaluation of ultrasonography for its diagnosis: a retrospective analysis

Pathologists usually explore extrathyroidal extensions (ETEs) in thyroid cancer; however, sonographers are often not concerned with ETEs. We investigated factors influencing ETEs and the efficacy of ultrasound evaluation of thyroid capsule invasion. We retrospectively analysed 1933 papillary thyroid carcinoma patients who underwent thyroidectomy during 2018-2021. Patients were divided into three groups: no ETE, minor ETE (mETE), and gross ETE. Clinical characteristic differences were assessed using binary logistic regression analysis to identify ETE predictors, and the kappa test was performed to analyse consistency between ultrasonographic and pathological diagnoses of ETE. The mETE group was more likely to have larger tumour diameters and more extensive lymph node metastasis (LNM) than the no ETE group and more likely to be diagnosed in the isthmus. In the multivariate logistic regression analysis, longest tumour diameter, lesion site, LNM extent, and thyroglobulin concentration were significant mETE predictors. Minimal consistency existed between pathological and ultrasonographic examinations for neighbouring tissue invasion. Many clinical differences were observed between the no ETE and mETE groups, suggesting the importance of considering mETE. Therefore, sonographers should pay more attention to relationships between nodules and capsule and indicate these on ultrasound reports to provide more accurate preoperative ETE information for surgeons.

The value of total tumor diameter in unilateral multifocal papillary thyroid carcinoma: a propensity score matching analysis

Background

Tumor multifocality is frequently observed in papillary thyroid carcinoma (PTC). However, the maximum tumor diameter (MTD), currently utilized in various staging schemes, might not accurately indicate the level of aggressiveness exhibited by multifocal tumors. We aimed to investigate the relationship between total tumor diameter (TTD) and clinicopathological features of papillary thyroid carcinoma.

Methods

Retrospective data analysis was done on 1936 individuals who underwent complete thyroidectomy for PTC. Patients were classified into subgroups according to unilateral multifocality, central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM). The relationships of clinicopathological features among these groups were analyzed.

Results

Unilateral multifocality was observed in 117 patients. The clinicopathological features of the unilateral multifocal PTC were similar to the unifocal PTC with approximate TTD. The unilateral multifocality played no independent role in CLNM and LLNM. Moreover, the efficiency of TTD in predicting CLNM and LLNM was significantly higher than that of MTD.

Conclusion

In the case of unilateral multifocal PTC, TTD is a more accurate indicator of the biological characteristics of the tumor than MTD.

Patient decision aids for patients with differentiated thyroid carcinoma: development process and alpha and beta testing

Background

Patient decision aids (PtDAs) are structured clinical tools that facilitate shared decision-making. Two important treatment decisions for patients with differentiated thyroid cancer (DTC), which could benefit from PtDAs, are as follows (1): the extent of surgery decision in patients with low-risk DTC and (2) the decision to start or delay starting the treatment with tyrosine kinase inhibitors (TKIs) in patients with advanced tumors.

Material and methods

PtDAs for these two decisions were developed using the International Patient Decision Aids Standards (IPDAS) quality criteria in an iterative process of prototype development via alpha and beta testing by patients and physicians. The information content of the PtDAs was based on the available literature, current guidelines, and patient's needs, preferences, and values.

Results

The web-based PtDAs underwent two rounds of alpha testing, revisions, and beta testing. The PtDAs have the same structure, consisting of six steps: a general introduction, information about the treatment options, comparing the treatment options, knowledge questions, a values clarification exercise, and saving the information. The alpha testing (n = 8 patients, n = 10 physicians) showed that the PtDAs were highly acceptable and usable for decision-making. Results of the beta testing in 20 patients showed that two patients did not use the PtDA; the other 18 patients found that the PtDAs were readable (n = 17) and helpful (n = 14) for decision-making. All patients recommend using the PtDAs.

Conclusions

Evidence-based PtDAs were created for patients with DTC for two different treatment decisions. Our final version was judged to be clear, balanced, and helpful in decision-making.

Comparison of clinicopathological characteristics and survival between symptomatic and asymptomatic anaplastic thyroid carcinoma

Although anaplastic thyroid carcinoma (ATC) is a fatal form of thyroid cancer with an overall survival of only a few months, there are some factors associated with longer survival. However, it remains unknown whether asymptomatic ATC differs from symptomatic ATC in terms of characteristics and overall prognosis. Therefore, we aimed to examine the clinicopathological characteristics and prognosis of asymptomatic ATC compared with those of symptomatic ATC. We retrospectively reviewed the medical records of 113 patients with ATC who were registered at our institution between November 1994 and July 2020. A total of 86 patients (59 women and 27 men; mean age, 66.9 ± 11.1 years) were enrolled for analysis. The clinicopathological characteristics of the ATC cohort were evaluated, and prognostic factors associated with disease-specific mortality were assessed. Of the 86 patients with ATC, 78 were symptomatic and eight were asymptomatic. Compared with the symptomatic group, the asymptomatic group had a younger age at diagnosis (59.3 ± 10.3 vs. 67.7 ± 11.0 years, p = 0.045), smaller tumor size (2.8 ± 1.2 vs. 5.8 ± 2.0 cm, p < 0.001), and longer survival period (37.5 ± 46.4, 9.5 ± 16.8 months, p < 0.001). However, the ATC component (%) of the tumor, sex, ultrasonographic risk category, and distant metastasis at diagnosis did not differ significantly between the two groups. In the multivariate Cox regression analysis, asymptomatic ATC (HR: 0.33, 95% CI 0.11-0.99, p = 0.045) and absence of distant metastasis (hazard ratio (HR): 0.56, 95% Confidence interval (CI) 0.35-0.88, p = 0.012) were associated with longer survival. Patients with asymptomatic ATC have a smaller tumor size, a longer survival period, and a younger age than those with symptomatic ATC. Being asymptomatic and having no distant metastasis were associated with longer survival in patients with ATC in a clinical setting.

Genetic and clinical profiles of 160 papillary thyroid cancers with lateral neck lymph node metastasis

Background

Lymph node metastasis is widespread in papillary thyroid cancer (PTC). Patients are more vulnerable than those with central lymph node metastasis if they have lateral neck lymph node metastasis (LLNM). There are few researches focus on the correlation between clinical characteristics and genetic profile of PTC with LLNM. In this study, we aimed to analyze the clinical and genetic features of PTC with LLNM.

Methods

A total of 160 primary tumor samples derived from PTC patients with LLNM were involved. Targeted next-generation sequencing was carried out on all samples with 57 known thyroid-cancer-related genes. The associations between genomic alternations and clinical characteristics of PTC with LLNM were statistically evaluated.

Results

The median age of patients was 37 years, ranging from 5 to 77 years and the female/male ratio was 1.86. The most frequently altered genes in our series were BRAF mutation (68%), followed by RET fusion (17%), TERT promoter mutation (5%) and PIK3CA mutation (2%). To be noted, all PTC patients with LLNM of TERT promoter mutations appeared along with BRAF mutations (8/8) and half of them experienced a relapse. Intriguingly, we found more metastatic lymph nodes in patients with RET fusion, but there was no statistically significant difference in metastatic lymph node ratio than those with BRAF mutation or without mutation. A high rate of gene fusion (70%) was found in the pediatric population, with aggressive late-onset disease.

Conclusions

PTC patients with LLNM is characterized by a high rate of BRAF mutation. Due to the observed clinicopathological differences in those patients among different alterations, further prospective studies are needed to verify our results and to evaluate the most suitable treatment strategies.

Differential diagnosis of diffuse sclerotic thyroid papillary carcinoma and Hashimoto's thyroiditis using fine-needle aspiration cytology, BRAFV600E , and ultrasound elastography

BACKGROUND

The diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) has ultrasound findings that are similar to Hashimoto's thyroiditis (HT), resulting in under-diagnosis. DSV-PTC combined with HT is also common, so early and accurate diagnosis of DSV-PTC using a variety of diagnostic techniques, including FNAC, BRAF^V600E mutation detection, and ultrasound elastography, is critical.

OBJECTIVE

To assess the diagnostic value of fine-needle aspiration cytology (FNAC) and BRAF^V600E detection in combination with ultrasound elastography in the diagnosis of DSV-PTC.

METHODS

We performed a retrospective analysis of 40 patients with pathologically confirmed DSV-PTC and 43 patients with HT admitted to our hospital's ultrasound department between January 2015 and December 2020. Preoperative FNAC, BRAF^V600E mutation detection, and ultrasound elastography imaging were all performed on all patients. For a definitive diagnosis, the results of these tests were compared to postoperative pathological findings. The diagnostic value of FNAC, BRAF^V600E mutation detection, ultrasound elasticity imaging, and their combination for DSV-PTC diagnosis was assessed.

RESULTS

The mean elastic strain rate ratio (E1/E2) of the 40 DSV-PTC cases was 5.75 ± 2.14, while that of the 43 HT cases was 2.81 ± 1.20. The receiver operating characteristic (ROC) curve was generated using the average value of E2/E1. The area under the ROC curve was 0.910, and the optimal E2/E1 cut-off value was 4.500. When FNAC, BRAF^V600E mutation detection, and ultrasound elasticity imaging detection were combined, the diagnostic sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of DSV-PTC diagnosis were 92.5%, 95.3%, 93.2%, 94.9%, and 94.0%, respectively, which were significantly higher than the single technique (p < 0.05).

CONCLUSIONS

The use of FNAC, BRAF^V600E mutation detection, and ultrasound elastography in combination is more helpful in establishing an accurate diagnosis of DSV-PTC than using a single diagnostic technique alone.

The influence of incidental detection of thyroid nodule on thyroid cancer risk and prognosis-A systematic review

BACKGROUND

Clinically inapparent thyroid nodules discovered serendipitously on imaging for nonthyroid indications are termed as thyroid incidentalomas. It is unclear whether these incidentalomas have a lower prevalence of malignancy or slower tumour progression compared to symptomatic nodules. The aims of this systematic review were to determine the impact of incidental detection of thyroid nodules on both the risk of malignancy and on prognosis in patients with thyroid cancer.

METHOD

PubMed and MEDLINE® on Web of Science databases were searched from inception to March 2020 for English language articles reporting on human studies of thyroid cancer risk and/or prognosis in incidental and nonincidental nodules.

RESULTS

Eighteen observational studies published between 1998 and 2020 were eligible for analysis; four studies reported on risk, nine on prognosis and five studies reported on both risk and prognosis. When comparing the incidental and nonincidental groups in the risk study, the odds of incidental detection in the cancer and benign groups ranged from 0.16 to 0.5 and 0.06 to 0.38, respectively (odds ratio [OR] = 0.64-2.86) in case-control studies (n = 6); the risk of malignancy for thyroid nodules ranged from 4% to 23.5% in the incidental and 3.8% to 28.7% in the nonincidental groups (relative risk = 0.13-6.27) in the cohort studies (n = 3). A meta-analysis of the eligible case-control studies (n = 3) showed a nonsignificant summated OR of 1.04 (95% confidence interval = 0.63-1.70; p = .88). In the prognosis study, five direct and thirteen indirect markers of prognosis were compared between the incidental and nonincidental groups. A meta-analysis was not possible but incidentally detected thyroid cancer had better progression-free and overall survival.

CONCLUSION

Current evidence suggests that investigation and management of thyroid nodules should not be influenced by the mode of detection.

Needs, Preferences, and Values during Different Treatment Decisions of Patients with Differentiated Thyroid Cancer

Background: The purpose of this study was to identify the needs, preferences, and values of patients with differentiated thyroid cancer (DTC) and the physicians treating patients with DTC regarding two different treatment decisions, namely: the extent of primary surgery (low-risk patients) and the tyrosine kinase inhibitor (TKI) treatment (high-risk patients). Methods: A qualitative study was conducted. There were two physician focus groups discussing the extent of primary surgery. One included endocrinologists (n = 4) and surgeons (n = 5), and the other included nuclear medicine physicians (n = 3) treating patients with low-risk DTC. The physicians focus group discussing waiting or starting TKIs included endocrinologists (n = 2) and oncologists (n = 5) treating patients with advanced radioactive iodide (RAI) refractory DTC. Moreover, one patient focus group per treatment decision took place. In total 13 patients and 19 physicians participated. Interviews were audio-taped, fully transcribed verbatim, and analyzed. Results: Several themes were identified. Patients, but not physicians, mentioned the importance of a strong doctor–patient relationship. Patients in both treatment decision groups wanted to receive more detailed information, whereas physicians preferred providing more general information. Patients in the TKI decision group focused on palliative care, whereas physicians focused more on the effect and benefit of TKIs. Conclusions: Considering the identified themes in DTC, based on the patients’ needs, preferences, and values, enables us to improve doctor–patient communication and to develop decision support tools.

Extra-Thyroid Extension Prediction by Ultrasound Quantitative Method Based on Thyroid Capsule Response Evaluation

Background

The aim of this study was to assess the interaction between thyroid malignancies and thyroid anterior capsule by ultrasound quantification to determine extra-capsular invasion.

Material/Methods

A total of 145 patients preoperatively diagnosed with malignant nodules under the thyroid anterior capsule were selected and routinely examined by ultrasound. The length of the nodules (from the junction of the nodule capsule to the deepest point of the nodule, vertical diameter, V) and the distance between the nodule protruding from thyroid capsule and the highest protruding (ledge length, L) nodule were used to obtain the L/V ratio. These parameters where then used to compare the efficacy of predicting extra-thyroid extension (ETE) between L/V, the aspect ratio of the tumor, and manual judgment.

Results

Out of 145 nodules, there were 63 ETEs and 82 non-ETEs determined by ultrasound. Extra-capsular invasion was associated with L//V ratio, but there was no significant correlation between capsular invasion and AR (aspect ratio), age, location, or presence of clustered calcification. The ability of the ratio of L/V to predict extra-capsular invasion was superior to the predictive ability of the AR ratio. With a Youden index of 0.593, the L/V ratio was 0.2325. The use of the L/V ratio to determine the presence of ETE was superior to subjective visual judgment.

Conclusions

The calculation of L/V ratio by ultrasound could more precisely predict the ETE compared with manual judgment, which indirectly reflects the interaction between thyroid capsule and malignant nodules. The above conclusions need to be confirmed by a range of cases.

A double mutation of BRAF L597Q and V600E in situ and solitary brain metastasis of occult papillary thyroid carcinoma: A case report

RATIONALE

The rare BRAF L597Q (c.T1790A) point mutation has been previously reported in childhood acute lymphoblastic leukemia. We present the first rare case of occult papillary thyroid carcinoma with BRAF L597Q mutation in a Tibetan patient.

PATIENT CONCERNS

A 57-year-old male patient presented with a protruding mass on the left forehead for 2 years and numbness in the right limb for 3 weeks.

DIAGNOSES

The patient had a double mutation of BRAF L597Q and V600E in 2 separate lesions at thyroid and brain, the immunohistochemical staining showed that the cytokeratin (CK), thyroglobulin (Tg) and thyroid transforming factor-1 (TTF-1) were immunoreactive. All the findings supported the diagnosis of solitary brain metastasis of occult papillary thyroid carcinoma.

INTERVENTIONS

The patient underwent left frontal lobe metastasis (thyroid cancer) resection that involved craniectomy and artificial skull repair.

OUTCOMES

During the 24-month follow-up, no postoperative complications or recurrence and metastasis were found.

LESSONS

This is the first case of solitary brain metastasis of occult papillary thyroid carcinoma with double mutation of BRAF L597Q and V600E in 2 separate lesions reported in the literature. Our study extends the disease spectrum of occult papillary thyroid carcinoma and suggests that the BRAF L597Q mutation might play a specific role in inducing the solitary brain metastasis of occult papillary thyroid carcinoma in a Chinese Tibetan patient, but the detailed molecular mechanism remains to be confirmed by a large number of functional experiments and clinical research.

Surgical Management of Diffuse Sclerosing Variant of Papillary Thyroid Carcinoma. Experience in 25 Patients

PURPOSE

To delineate the clinicopathologic features and biologic behavior of the diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) and to report its outcome.

METHODS

The clinical records of 25 patients who had surgery for DSV-PTC from 2004 to 2017 were retrospectively analyzed. Comparisons were made to similar studies in the literature reporting ≥8 cases and a cohort of classical PTC.

RESULTS

There were 20 females and 5 males with an average age of 23 years (range 10-39 years). Bilateral disease occurred in 80% of cases. The mean size of the dominant mass was 4.2 ± 1.92 cm. In 92% of cases, therapeutic neck dissection was performed. Male sex significantly correlated with a higher yield of positive lymphadenopathy (p = 0.045). 62% of patients had recurrent disease. Recurrence significantly correlated with male sex, the number of metastatic lymph nodes (cutoff: 22 lymph nodes), and multifocality (p = 0.044, p ˂ 0.008, p ˂ 0.003, respectively). However, it did not correlate with the age at presentation. No disease-specific mortality occurred after an average follow-up of 77 months (range 12-168 months). The two comparisons made demonstrated a statistically significant greater tendency of the current series of DSV-PTC toward more aggressive clinicopathologic features and biologic behavior. No differences in overall survival were observed.

CONCLUSION

The DSV-PTC should be considered a high-risk PTC that mandates an aggressive therapeutic strategy with the intent of optimizing disease-free survival.

The Impact of the Extent of Surgery on the Long-Term Outcomes of Patients with Low-Risk Differentiated Non-Medullary Thyroid Cancer: A Systematic Meta-Analysis

Recently, the management of patients with low-risk differentiated non-medullary thyroid cancer (DTC), including papillary and follicular thyroid carcinoma subtypes, has been critically appraised, questioning whether these patients might be overtreated without a clear clinical benefit. The American Thyroid Association (ATA) guideline suggests that thyroid lobectomy (TL) could be a safe alternative for total thyroidectomy (TT) in patients with DTC up to 4 cm limited to the thyroid, without metastases. We conducted a meta-analysis to assess the clinical outcomes in patients with low-risk DTC based on the extent of surgery. The risk ratio (RR) of recurrence rate, overall survival (OS), disease-free survival (DFS) and disease specific survival (DSS) were estimated. In total 16 studies with 175,430 patients met the inclusion criteria. Overall, low recurrence rates were observed for both TL and TT groups (7 vs. 7%, RR 1.10, 95% CI 0.61-1.96, I² = 72%), and no statistically significant differences for OS (TL 94.1 vs. TT 94.4%, RR 0.99, CI 0.99-1.00, I² = 53%), DFS (TL 87 vs. TT 91%, RR 0.96, CI 0.89-1.03, I² = 85%), and DSS (TL 97.2 vs. TT 95.4%, RR 1.01, CI 1.00-1.01, I² = 74%). The high degree of heterogeneity of the studies is a notable limitation. Conservative management and appropriate follow-up instead of bilateral surgery would be justifiable in selected patients. These findings highlight the importance of shared-decision making in the management of patients with small, low-risk DTC.

Risk factors of skip lateral lymph node metastasis in papillary thyroid carcinoma

PURPOSE

Cervical lymph node metastasis is a prognostic factor of papillary thyroid carcinoma (PTC). This study aimed to investigate clinicopathological features and risk factors of skip lateral lymph node metastasis in PTC patients.

METHODS

We retrospectively reviewed medical records of patients who underwent simultaneous total thyroidectomy with therapeutic central compartment lymph node dissection (LND) and lateral LND for primary PTC from 2014 to 2019. Univariate and multivariate logistic regression analyses were performed to identify clinicopathologic risk factors for skip metastasis. Receiver-operating characteristic (ROC) curves were constructed using the results of the multiple logistic regression analysis to identify data points with the highest sensitivity and lowest false-negative rate.

RESULTS

The frequency of skip metastasis was approximately 12.8% (50/390). Multivariate logistic regression analysis showed that age (odds ratio [OR], 1.033; 95% confidence interval [CI], 1.008-1.059; P = 0.010), tumor size (OR 0.251; 95% CI 0.129-0.490; P < 0.001) and tumor located in the upper portion (OR 0.378; 95% CI 0.200-0.715; P = 0.003) were independent risk factors of skip metastasis (all P < 0.05). The ROC curves showed that the cut-off value of age for predicting skip metastasis was 44.5 years old (sensitivity = 0.620, specificity = 0.618, area under the curve [AUC] = 0.627, P = 0.004); the cut-off value of the tumor diameter for predicting skip metastasis was 1.05 cm (sensitivity = 0.503, specificity = 0.760, AUC = 0.682, P < 0.001).

CONCLUSIONS

Skip metastasis was common in PTC. The PTC patients with age > 44.5 years, tumor diameter < 1.05 cm and tumor located in the upper portion should be carefully evaluated for skip metastasis.

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.

A potential biomarker hsa-miR-200a-5p distinguishing between benign thyroid tumors with papillary hyperplasia and papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most common endocrine cancer with a significantly increase of the incidence recently. Several cytokines, such as thyroid peroxidase (TPO), cluster of differentiation 56 (CD56), Galectin-3, mesothelial cell (MC), cytokeratin 19 (CK19) and BRAF (B-raf) were recommended to be tested by immunohistochemistry (IHC) for a definitive diagnosis, but were still limited in clinical use because of their relative lower sensitivity and specificity. MicroRNA (miRNA), as a new molecular biomarkers, however, has not been reported yet so far. To address this, hsa-miR-200a-5p, a miRNA, was selected and detected in PTC patients by in situ hybrization with benign thyroid tumor with papillary hyperplasia as a control, and the differential expression of hsa-miR-200a-5p between fresh PTC tissues and control was detected by qRT-PCR. Expressive levels of cytokines of TPO, CD56, Galectin-3, MC, CK19 and B-raf were also detected by immunohistochemistry. The correlation was analyzed by SPSS software using Spearman methods. As expected, the hsa-miR-200a-5p expressive level was significantly increased in PTC patients, compared to that of control, and was consistent with that of TPO, CD56, Galectin-3, MC, CK19 and B-raf. In addition, expression of hsa-miR-200a-5p showed negative correlation to that of TPO (rs = - 0.734; **: P < 0.01) and CD56 (rs = - 0.570; **: P < 0.01), but positive correlation to that of Galectin-3 (rs = 0.601; **: P < 0.01), MC (rs = 0.508; **: P < 0.01), CK19 (rs = 0.712; **: P < 0.01) and B-raf (rs = 0.378; **: P < 0.01). PTC and papillary benign thyroid papillary hyperplasia are difficult to distinguish in morphology, so requiring immunohistochemistry to further differentiate the diagnosis, however, for the existing clinical common diagnostic marker for immunohistochemistry, the sensitivity and accuracy are low, it is easy to miss diagnosis. Therefore, there is an urgent need for a rapid and sensitive molecular marker. So miR-200a-5p can be used to assist in the diagnosis of PTC at the molecular level, and as a biomarker, can be effectively used to distinguish between PTC and benign thyroid tumor with papillary hyperplasia.

Mps1 is associated with the BRAFV600E mutation but does not rely on the classic RAS/RAF/MEK/ERK signaling pathway in thyroid carcinoma

In previous studies, the B-Raf proto-oncogene, serine/threonine kinase (BRAF)^V600E mutation has been identified in multiple malignant tumors. BRAF^V600E has been revealed to contribute to tumorigenesis by the activation of phospho-mitogen-activated protein kinases (MAPKs) and their downstream Monopolar spindle 1 (Mps1), leading to chromosome euploidy and tumor development. In the present study, the presence of phospho-MAPK and Mps1 in 161 thyroid carcinoma cases with complete clinical parameters was analyzed by immunohistochemistry, and the BRAF mutation was detected by polymerase chain reaction-direct sequencing. It was revealed that BRAF^V600E was present in ~34% of thyroid cancer cases and was associated with age, clinical tumor stage and lymph node stage. However, the association of BRAF^V600E with overall survival was not statistically significant. The expression of Mps1 was significantly increased in tumor tissues with BRAF^V600E, however, this did not affect the expression of phospho-MAPK in thyroid carcinomas. Collectively, the results of the present study suggested that BRAF^V600E may regulate the expression of Mps1 in MAP kinase independent ways in thyroid carcinoma. Therefore, Mps1 expression is associated with BRAF^V600E while the upstream signaling of phospho-MAPK has no relevance. The specific mechanisms of BRAF^V600E and the unknown pathway associated with Mps1 exhibit potential for further study, and provide a theoretical basis for the molecular treatment of thyroid carcinoma.