Unique patterns of tumor growth related with the risk of lymph node metastasis in papillary thyroid carcinoma

Multifocal Papillary Thyroid Carcinomas With Discordant Molecular Drivers: Emphasizing the Morphology and Collision Tumors

Multifocal papillary thyroid carcinomas (PTCs) are common and the majority of the tumors harbor mutual BRAF p.V600E mutation. This study aimed to investigate a contemporary series of multifocal PTCs with discordant molecular drivers. Consecutive thyroidectomies diagnosed with multifocal PTCs ≥0.5 cm between 2019 and 2023 were reviewed. Immunohistochemistry (IHC) for BRAF VE1 was performed for all tumors. Cases with discordant BRAF IHC results or morphologic discrepancy were identified, and BRAF IHC-negative tumors were subjected to RAS Q61R IHC and/or targeted RNA next-generation sequencing. A total of 770 patients with a main PTC ≥0.5 cm were identified; 255 (33.1%) had multifocal disease, and 142 (18.4%) had at least another PTC ≥0.5 cm. Among them, 13 cases (9.2%, 13/142) had discordant molecular drivers. Twelve cases had one or more BRAF-positive PTCs accompanied by a BRAF-negative PTC (3 with CCDC6::RET fusion, 1 with NCOA4::RET fusion, 1 with ACBD5::RET fusion, 2 with ETV6::NTRK3 fusion, 1 with TG::FGFR1 fusion, 1 with LMTK2::BRAF fusion, 1 with AGK::BRAF fusion and RAS p.Q61R mutation, 1 with RAS p.Q61R mutation, and 1 without detectable molecular drivers). The last case had tumors with discordant fusion drivers (VIM::NTRK3 and TNS1::BRAF). Most cases showed tumors that were morphologically distinct (92.3%, 12/13) and occurred in the contralateral lobes (76.9%, 10/13). Notably, we identified 4 cases (30.8%) that presented as collision tumors and 6 cases (46.2%) that showed lymph node metastases, including 2 with simultaneous involvement by tumors with discordant molecular drivers, as novel findings. In summary, a subset (9.2%) of multifocal PTCs had discordant molecular drivers and 84.6% of them were a combination of BRAF-positive and kinase gene fusion-associated PTCs, most with distinct morphologies. Almost half of the cases had nodal metastasis and a third of them showed simultaneous involvement by tumors with discordant molecular drivers. The results highlight the clinical importance of identifying such cases, given the potentially different treatments.

Diagnostic utilities of washout CYFRA 21-1 combined with washout thyroglobulin for metastatic lymph nodes in thyroid cancer: a prospective study

Cervical lymph node (LN) metastasis is common in differentiated thyroid cancer (DTC). This study evaluated the utility of the washout CYFRA 21-1 level, combined with the thyroglobulin (Tg) concentration, in terms of diagnosis of LN metastasis. We prospectively enrolled 53 patients who underwent thyroid surgery to treat DTC with lateral cervical LN metastases. Preoperative ultrasound guided needle localization was used to surgical sampling of specific LNs during the operation. The intraoperative washout Tg and CYFRA 21-1 levels were measured in such LNs. The Tg and CYFRA 21-1 levels differed significantly between metastatic and benign LNs. The cutoff values were 2.63 ng/mL for washout CYFRA 21-1 and 22.62 ng/mL for Tg. Combined use of the washout Tg and CYFRA 21-1 levels afforded the highest diagnostic accuracy (92.5%), better than that of individual markers. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) were 94.6%, 90.0%, 91.4%, 93.8%, respectively. The conjunction of the washout CYFRA21-1 and Tg levels enhances the diagnostic accuracy of LN metastasis in DTC patients. The washout CYFRA 21-1 level may be useful when malignancy is suspected, especially in cases where the cytology and washout Tg findings do not provide definitive results.

BRAFV600E Positivity-Dependent Effect of Age on Papillary Thyroid Cancer Recurrence Risk

BRAFV600E positivity is associated with increased aggressiveness of papillary thyroid cancer (PTC), and age is an important prognostic factor. However, the association between age and BRAFV600E positivity and the recurrence risk has not been investigated. This study aimed to investigate the impact of age on recurrence between patients with BRAFV600E-positive and -negative PTC. Patients with PTC who underwent initial thyroid surgery between January 2010 and December 2018 at Seoul St. Mary's Hospital (Seoul, Republic of Korea) were retrospectively reviewed. The BRAFV600E-positive (n = 1768) and BRAFV600E-negative groups (n = 428) were divided into two subgroups: younger (<35 years) and older groups (≥55 years). In the BRAFV600E-positive group, the younger group exhibited higher lymphatic and vascular invasion rates, more positive lymph nodes, higher lymph node ratios, and higher recurrence rates than the older group (5.9% vs. 2.1%). Multivariate analysis revealed that age, lymphatic invasion, and N category were significant risk factors in the BRAFV600E-positive group. In the BRAFV600E-positive group, the younger group had a higher recurrence risk than the older group (OR, 2.528; 95% confidence interval, 1.443-4.430; p = 0.001). In the BRAFV600E-negative group, age had no impact on recurrence risk. These results contribute to tailored treatment strategies and informed patient management.

Clinical Significance of Tumor Size in Gross Extrathyroidal Extension to Strap Muscles (T3b) in Papillary Thyroid Carcinoma: Comparison with T2

The purpose of the present study was to compare the risk of recurrence between T2 and T3b papillary thyroid carcinoma (PTC) and the effect of tumor size on survival in T3b disease. A total of 634 patients with PTC who underwent thyroid surgery at a single center were retrospectively analyzed. Clinicopathological characteristics were compared according to the T category in the TNM staging system, with T3b divided into T3b-1 (tumor size, ≤2 cm) and T3b-2 (tumor size, 2–4 cm). Disease-free survival (DFS) and recurrence risk were compared between T2, T3b, T3b-1, and T3b-2. Tumor size was significantly larger in T2 than in T3b. A significant difference in recurrence was observed between T2 and T3b-2 but not between T2 and T3b-1. T3b-2 was identified as a significant risk factor for PTC recurrence. A significant difference in the DFS curve was observed between T2 and T3b-2. However, no significant differences in survival were observed between T2 and T3b or T3b-1. These results indicate that the prognostic impact of T3b may vary depending on tumor size. Further studies are required to determine the need for T classifications that account for tumor size and gETE invasion of the strap muscles.

Infiltration pattern predicts metastasis and progression better than the T-stage and grade in pancreatic neuroendocrine tumors: a proposal for a novel infiltration-based morphologic grading

The advancing edge profile is a powerful determinant of tumor behavior in many organs. In this study, a grading system assessing the tumor-host interface was developed and tested in 181 pancreatic neuroendocrine tumors (PanNETs), 63 of which were <=2 cm. Three tumor slides representative of the spectrum (least, medium, and most) of invasiveness at the advancing edge of the tumor were selected, and then each slide was scored as follows. Well-demarcated/encapsulated, 1 point; Mildly irregular borders and/or minimal infiltration into adjacent tissue, 2 points; Infiltrative edges with several clusters beyond the main tumor but still relatively close, and/or satellite demarcated nodules, 3 points; No demarcation, several cellular clusters away from the tumor, 4 points; Exuberantly infiltrative pattern, scirrhous growth, dissecting the normal parenchymal elements, 5 points. The sum of the rankings on the three slides was obtained. Cases with scores of 3-6 were defined as "non/minimally infiltrative" (NI; n = 77), 7-9 as "moderately infiltrative" (MI; n = 68), and 10-15 as "highly infiltrative" (HI; n = 36). In addition to showing a statistically significant correlation with all the established signs of aggressiveness (grade, size, T-stage), this grading system was found to be the most significant predictor of adverse outcomes (metastasis, progression, and death) on multivariate analysis, more strongly than T-stage, while Ki-67 index did not stand the multivariate test. As importantly, cases <=2 cm were also stratified by this grading system rendering it applicable also to this group that is currently placed in "watchful waiting" protocols. In conclusion, the proposed grading system has a strong, independent prognostic value and therefore should be considered for integration into routine pathology practice after being evaluated in validation studies with larger series.

Periostin expression and its supposed roles in benign and malignant thyroid nodules: an immunohistochemical study of 105 cases

BACKGROUND

Thyroid tumors are often difficult to histopathologically diagnose, particularly follicular adenoma (FA) and follicular carcinoma (FC). Papillary carcinoma (PAC) has several histological subtypes. Periostin (PON), which is a non-collagenous extracellular matrix molecule, has been implicated in tumor invasiveness. We herein aimed to elucidate the expression status and localization of PON in thyroid tumors.

METHOD

We collected 105 cases of thyroid nodules, which included cases of adenomatous goiter, FA, microcarcinoma (MIC), PAC, FC, poorly differentiated carcinoma (PDCa), and undifferentiated carcinoma (UCa), and immunohistochemically examined the PON expression patterns of these lesions.

RESULTS

Stromal PON deposition was detected in PAC and MIC, particularly in the solid/sclerosing subtype, whereas FA and FC showed weak deposition on the fibrous capsule. However, the invasive and/or extracapsular regions of microinvasive FC showed quite strong PON expression. Except for it, we could not find any significant histopathological differences between FA and FC. There were no other significant histopathological differences between FA and FC. Although PDCa showed a similar PON expression pattern to PAC, UCa exhibited stromal PON deposition in its invasive portions and cytoplasmic expression in its carcinoma cells. Although there was only one case of UCa, it showed strong PON immunopositivity. PAC and MIC showed similar patterns of stromal PON deposition, particularly at the invasive front.

CONCLUSIONS

PON may play a role in the invasion of thyroid carcinomas, particularly PAC and UCa, whereas it may act as a barrier to the growth of tumor cells in FA and minimally invasive FC.

Diffuse intrathyroidal dissemination of papillary thyroid carcinoma with no stromal fibrosis at presentation: A pattern of aggressive differentiated thyroid carcinoma

BACKGROUND

Multifocal Papillary thyroid carcinoma (PTC) is a very common condition. In certain cases, it is possible to find tens to hundreds of foci with a diffuse intrathyroidal spread in the whole thyroid with no stromal fibrosis. Herein, PTC with such features was nominated as diffuse disseminate variant (DDV) PTC. The aim of the present study was to investigate the histopathological characteristics, molecular features, and biological behavior of DDV and compare the characteristics of DDV to diffuse sclerosing variant (DSV) PTC.

MATERIALS AND METHODS

Thirty-four DDV and 23 DSV cases were identified from consecutive surgical specimens diagnosed with PTC between 2014 and 2019. Targeted next-generation sequencing (NGS) was applied to investigate the mutation spectrum of DDV and DSV.

RESULTS

DDV was commonly diagnosed in young patients and exhibited high rates of LNM (100 %), ETE (61.8 %), and LVI (44.1 %); however, they did not differ from DSV (P >  0.05). Male patients were more frequently diagnosed with DDV than with DSV (P <  0.001). The size of the largest tumor was significantly greater in DDV than in DSV patients (P =  0.008). In addition, BRAF^V600E mutation was significantly higher in the DDV than in the DSV group (P <  0.001). The RET/PTC rearrangement was more frequent in DSV than in DDV patients; however, the difference was not statistically significant (P =  0.106). Moreover, DDV had a higher rate of recurrence compared to DSV treated with the same protocol (total thyroidectomy followed by radioactive iodine (RAI) treatment) (47.1 % and 8.7 %, P =  0.002).

CONCLUSIONS

DDV should be regarded as a novel aggressive variant of PTC with distinct clinicopathological characteristics, aggressive biological behaviors, and a high recurrence.

Ultrasound Echogenicity of Papillary Thyroid Cancer Is Affected by Tumor Growth Patterns and Tumor Fibrosis

BACKGROUND/AIM

The association between preoperative ultrasound (US) echogenicity and histopathological characteristics of papillary thyroid cancer (PTC) has been rarely investigated is not well characterized. This study evaluated a relationship between the clinical characteristics of PTC, histopathological phenomena including tumor growth patterns (TGPs) and tumor fibrosis (TF), and US echogenicity.

PATIENTS AND METHODS

In total, 170 patients with PTC (<2 cm) underwent total thyroidectomy with central neck dissection. Demographics, US echogenicity, tumor size, extra-thyroidal extension (ETE), lymph node metastasis (LNM) within the central and lateral neck, TGPs, and TF percentage were reviewed.

RESULTS

Patients with TGP II (encapsulated growth with partial pericapsular extension) and III (infiltrative growth) were more frequently burdened by ETE and lateral neck LNM compared to patients with TGP I (encapsulated growth with a well-defined cystic or solid characteristic). Older age was significantly deterministic of TGP III, and male gender and higher TF percentage were independent risk factors for lateral neck LNM. TGP III and TF were independent determining factors for marked hypoechogenicity on US.

CONCLUSION

PTC with TGP II and III and higher tumor fibrosis exhibited more aggressive clinicopathologic behaviors. TGP III and TF were determinants for marked hypoechogenicity.

Prognostic Assessment of BRAF Mutation in Preoperative Thyroid Fine-Needle Aspiration Specimens

OBJECTIVES

We investigate the potential role of BRAF testing in guiding surgical intervention in papillary thyroid carcinoma (PTC).

METHODS

Thyroid fine-needle aspiration (FNA) cases with available BRAF result and follow-up thyroidectomy for PTC were included in the study. Cytology and surgical diagnoses were correlated with BRAF status.

RESULTS

There were 151 cases of thyroid FNA specimens with BRAF testing (70 mutant and 81 wild-type BRAF) and histologically confirmed unilateral, unifocal PTCs. There were no differences in age, sex, tumor size, or lymphovascular invasion on thyroidectomy specimens between mutant and wild-type BRAF cases. BRAF mutation was significantly associated with cytology diagnosis (P < .001), PTC subtype (P < .001), extrathyroidal extension (ETE) (P = .006), and higher tumor (T) stage (P = .04). However, an analysis within the histologic subtypes of PTC revealed no significant association between BRAF mutation and ETE or higher T stage. There was also no difference in central (P = .847) or lateral (p = 1) neck lymph node (LN) metastasis.

CONCLUSIONS

BRAF mutation identified in thyroid FNA specimens correlates with histologic subtypes but is not an independent factor for predicting PTC biological behavior and should not be used to guide the extent of LN dissection.

Unilateral Multifocality and Bilaterality Could Be Two Different Multifocal Entities in Patients with Papillary Thyroid Microcarcinoma

OBJECTIVE

Multifocality within an affected lobe (unilateral multifocality) or two lobes (bilaterality) is commonly denoted as multifocality without differentiation. Recently, there has been molecular evidence indicating that unilateral multifocality and bilaterality could be two different entities. However, few studies concerning the comparison between these two different multifocality entities have been reported.

DESIGN

A retrospective cohort study.

METHODS

From 2010 to 2013, in total, 949 consecutive patients with papillary thyroid microcarcinoma (PTMC) were enrolled and further divided into four groups based on multifocality status. Unilateral multifocality and bilaterality were analyzed by binary logistic regression along with other clinicopathological factors.

RESULTS

Unilateral multifocality, instead of bilaterality, was correlated with central neck metastasis (CNM) in both univariate and multivariate analyses. Group IV (unilateral multifocality and bilaterality coexist) had the highest CNM rate. Group III (unilateral multifocality) had a higher CNM rate than group II (bilaterality, single lesion in each lobe), with a significant difference (p = 0.032). Similar lateral neck metastasis tendency was observed among the four groups. In the multivariate analysis, only unilateral multifocality and bilaterality which coexisted were correlated with CNM. Moreover, 9 cases had a recurrence, with the recurrence rate ranking top in group IV (3.6%), second in group III (2.8%), and third in group II (1.2%). The difference was significant (p = 0.021).

CONCLUSION

Unilateral multifocality and bilaterality could be two different multifocal entities in patients with PTMC. Unilateral multifocality serving as a prognostic factor indicated a worse prognosis than bilaterality on neck metastasis. When the two factors coexisted in PTMC, patients had the highest risk of CNM and possibly local recurrence compared with those with either risk factor alone.

Predictive factors for central lymph node metastases in papillary thyroid microcarcinoma

Papillary thyroid microcarcinoma (PTMC) measures 1 cm or less in its longest dimension. The incidence of PTMC is increasing worldwide. Surgery is the primary treatment; however, prophylactic central lymph node dissection is controversial, and discrepancies between different guidelines have been noted. Routine prophylactic central lymph node dissection may result in hypoparathyroidism and recurrent laryngeal nerve injury in some patients without lymph node metastasis, while simple thyroidectomy may leave metastatic lymph nodes in high-risk patients. To selectively perform prophylactic lymph node dissections in high-risk patients, it is important to identify predictive factors for lymph node metastases in patients with PTMC. Several studies have reported on this, but their conclusions are not entirely consistent. Several clinicopathologic characteristics have been identified as risk factors for central lymph node metastases, and the most commonly reported factors include age, gender, tumor size and location, multifocality, bilaterality, extrathyroidal extension, and abnormal lymph node found using ultrasound. Here, we provide an overview of previous studies along with a favorable opinion on or against these factors, with the aim of increasing the understanding of this topic among the medical community. In addition, current opinions about prophylactic central lymph node dissection are reviewed and discussed.

A meta-analysis evaluating the relationship between B-type Raf kinase mutation and cervical lymphatic metastasis in papillary thyroid cancer

BACKGROUND

B-type Raf kinase (BRAF) mutation is proved to be a critical predictive factor in papillary thyroid cancer (PTC) with aggressive characteristics. However, the association between BRAF mutation and cervical lymphatic metastasis in PTC is controversial.

METHODS

We searched papers on the study of BRAF mutation and cervical lymphatic metastasis in PTC patients through PubMed, Web of Science, Embase, and Cochranelibrary. The BRAF (+) cases, BRAF (-) cases, and cervical lymphphatic metastatic cases in both BRAF (+) and BRAF (-) groups were collected. After Quality assessment, statistical Analysis (funnel plot and Harbord evaluation, Random-effect model, heterogeneity, subgroup analysis, sensitivity analysis, and metacum analysis) were done by the Review Manager (RevMan) 5.3 and stata14 statistical software.

RESULTS

There were 78 cross-section studies which met our inclusion criteria. And all of them had no selection bias, publication bias, or any other bias. A significant association existed between BRAF mutation and cervical lymph node metastasis (LNM) (odds ratio [OR] = 1.63; 95% confidence interval [CI]: 1.44-1.84; P < .05). Overall, 46 studies were conducted among East Asians. Twenty four articles had provided the data of central lymph node metastasis (CLNM), 11 articles with the data of lateral lymph node metastasis (LLNM), and classic/conventional PTC (CPTC) was analyzed in 10 studies. Subgroup analyses were performed based on ethnicity, metastatic site, and subtype of PTC. Significant association between BRAF (+) mutation and cervical LNM were indicated in East Asians (OR = 1.73; 95% CI: 1.49-2.02; P < .05), in non-East Asians (OR = 1.57; 95% CI: 1.26-1.96; P < .05), and in CLNM (OR = 1.80; 95% CI: 1.56-2.07; P < .05). While no significant association was found in LLNM (OR = 1.37; 95% CI: 0.76-2.48; P = .29 > .05) and in CPTC (OR = 1.32; 95% CI: 0.97-1.80; P = .08 > .05). We did not find any other major changes when sensitivity analysis was performed. The metacum analysis showed no significant association existed before 2012. While a significant association began to exist between BRAF mutation and LNM from 2012, and this association became stable from 2017.

CONCLUSIONS

We consider that a significant association exists between BRAF mutation and cervical LNM. Further meta-analysis on subgroup may reveal some valuable factors between BRAF gene mutation and LNM. And we do not recommend that BRAF (+) as the biomarker for LNM in PTC.

Predicting factors for central or lateral lymph node metastasis in conventional papillary thyroid microcarcinoma

BACKGROUND

Optimal management for papillary thyroid microcarcinoma (PTMC) remains controversial. The purpose of this study was to explore risk factors predictive of cervical lymph node metastasis in conventional PTMCs.

METHODS

Conventional PTMC patients (n = 2,404) undergoing surgery between 2010 and 2017 were grouped and analyzed according to the positivity of cervical lymph node.

RESULTS

Central lymph node (CLN) metastases and lateral lymph node (LLN) metastases were observed in 915 (38.1%) and 184 (7.7%) cases, respectively. Multivariate analysis found that male (odds ratio [OR] = 1.974, p < 0.001), younger age (OR = 1.601, p < 0.001), tumor size (OR = 1.935, p < 0.001), extrathyroidal extension (ETE) (OR = 1.647, p < 0.001), multifocality (OR = 1.416, p < 0.001), and intrathyroidal spreading (OR = 3.355, p < 0.001) predicted increased CLN metastasis. In particular, younger age, multifocality, and intrathyroidal spreading were significantly associated with a high number of CLN metastases (n ≥ 5). The presence of CLN metastasis was strongly associated with LLN metastasis (OR = 5.426, p < 0.001).

CONCLUSION

Male, younger age, tumor size, ETE, multifocality, and intrathyroidal spreading predict increased CLN metastasis in PTMCs. In patients with suspicious lateral lymphadenopathy, the presence of CLN metastasis is independently associated with LLN metastasis.

Association Between Preoperative US, Elastography Features and Prognostic Factors of Papillary Thyroid Cancer With BRAFV600E Mutation

Purpose: To investigate the value of US and elastography for predicting prognostic factors of papillary thyroid cancer (PTC) in the positive BRAF^V600E Mutation group. Materials and Methods: A total of 116 BRAF^V600E Mutation patients with PTCs were enrolled in this prospective study, who were preoperatively evaluated by US, US elasticity imaging (EI), and Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ) of acoustic radiation force impulse (ARFI) imaging. Multivariate logistic regression analysis was performed to assess 23 independent variables for predicting prognostic factors. Diagnostic performance was evaluated with receiver operating characteristic (ROC) curve analysis. Results: Forty-two (36.2%) of 116 PTC patients with BRAF^V600E Mutation had central lymph node metastasis (LNM). Nine (7.8%) and fifty-six (48.3%) had lateral LNM and extra-thyroidal extension (ETE), respectively. In multivariate logistic regression analyses, rich internal flow [odds ratio [OR]: 6.66] was the best predictor for central LNM, followed by male sex (OR: 4.22), halo sign absence (OR: 2.78) (all P < 0.05). VTQ ratio (OR: 1.57) was the only predictor for lateral LNM (P = 0.02). Rich internal flow (OR: 6.33) was the strongest predictor for ETE, followed by male sex (OR: 3.29), halo sign absence (OR: 2.90), and VTQ ratio (OR: 1.63) (all P < 0.05). Conclusion: VTQ ratio on ARFI imaging, rich internal flow and halo sign absence on US are the predicting prognostic factors in PTC patients with BRAF^V600E Mutation. The specificities were significantly increased by combining ARFI imaging and US features, which has a potential to avoid unnecessary therapeutic neck dissection in the high-risk PTC patients.

CCND1 Splice Variant as A Novel Diagnostic and Predictive Biomarker for Thyroid Cancer

Cyclin D1 protein is aberrantly overexpressed in thyroid cancers, but mutations of the CCND1 gene are rare in these tumors. We investigated the CCND1 rs9344 (G870A) polymorphism and the expression profiles of wild-type CCND1a and shortened oncogenic isoform CCND1b at the mRNA and protein levels in 286 thyroid tumors. Genotype AA of rs9344 was associated with high expression of CCND1b mRNA and was more frequently found in thyroid cancer than in benign tumors. The mRNA expression levels of CCND1b were higher in papillary thyroid carcinoma (PTC) than in benign or other malignant tumors. However, the expression of CCND1a mRNA showed no association with the parameters. Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was distinguished from PTC by low expression of CCND1b at mRNA and protein levels. We further observed that cyclin D1b immunostaining helped to avoid the misdiagnosis of classic PTC with predominant follicular pattern as NIFTP in a separate cohort. Nuclear cyclin D1b expression was associated with aggressive clinicopathologic features in PTC. These findings suggest that cyclin D1b overexpression can be used as a diagnostic and predictive biomarker in thyroid tumors and may be functionally involved in the development and progression of the disease.

Predictors for central lymph node metastases in CN0 papillary thyroid microcarcinoma (mPTC): A retrospective analysis of 1304 cases

BACKGROUND

Presence of lymph node metastases increases the risk of recurrence, but prophylactic central neck node dissection for patients with micropapillary thyroid cancer (mPTC) is controversial. We aim to find the clinical predictors of central lymph node metastases (CLNM) in patients with cN0 mPTC.

METHODS

We retrospectively reviewed the clinicopathological and molecular genetic characteristics of 1304 patients with cN0 mPTC operated at the First Hospital of Jilin University between January 1, 2013 and May 31, 2016, all underwent thyroid lobectomy or total thyroidectomy with unilateral or bilateral prophylactic central neck dissection. Univariate and multivariate analysis were used to identify the predictors of CLNM.

RESULTS

30.7% of cN0 mPTC patients had CLNM. Univariate analysis found CLNM to be associated with younger age (≤45), male gender, larger tumor (>0.5 cm), multifocality, bilaterality, capsular invasion, lymphovascular invasion and extrathyroidal infiltration, but not associated with BRAF mutation, tumor location, preoperative TSH and anti-thyroglobulin antibody level. Multivariate logistic regression showed age ≤45 years (p < 0.001, OR = 2.05), male gender (p < 0.001, OR = 1.94), tumor size >0.5 cm (p < 0.001, OR = 1.87), bilaterality (p = 0.003, OR = 1.86) and capsular invasion (p = 0.013, OR = 1.49) to be independent predictors for CLNM in cN0 mPTC patients.

CONCLUSIONS

Prophylactic central neck dissection has higher yield for cN0 mPTC patients with age ≤45 years, male gender, tumor size>0.5 cm, bilaterality and capsular invasion. BRAF mutation is not a predictor for CLNM in cN0 mPTC patients.

Skip metastasis in papillary thyroid carcinoma is difficult to predict in clinical practice

BACKGROUND

Cervical lymph node metastases are very common in papillary thyroid cancer (PTC), and typically spread in a predictable stepwise fashion in clinical practice. However, lateral lymph node metastasis (LLNM) without central lymph node metastasis (CLNM) as skip metastasis is not rare in PTC. The aim of this study was to investigate the incidence, risk factors and pattern of skip metastasis in PTC.

METHODS

A total of 271 patients with PTC and suspicious LLN diagnosed by pre-operation examinations who underwent total thyroidectomy and central lymph node dissection plus lateral lymph node dissection between January 2008 and December 2011 were enrolled in this study. Clinicopathological features were collected, and the pattern of cervical lymph node metastasis and skip metastasis were analyzed.

RESULTS

The LLNM rate was 74.9% (203/271, diagnosed by postoperative pathology examination) and significantly associated with extrathyroid extension (ETE), primary tumor located at the upper pole, and CLNM (p < 0.05). The skip metastasis rate was 14.8% (30/203) and was more frequently found in microcarcinoma patients, especially when the primary tumor size was ≤0.5 cm (p = 0.001 OR = 12.9). However, skip metastasis was unrelated to the remaining factors examined.

CONCLUSION

Small cancers with a pre-operation diagnosis of LLNM are more likely to have skip metastases, especially when the primary tumor size is less than 0.5 cm in diameter; however, this type of metastasis appears to develop in a random fashion. Thus, additional research is needed to identify potential predictive factors, such as a primary tumor located at the upper pole.

Prognostic implication of histological features associated with EHD2 expression in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is a heterogeneous tumor with various histological and molecular subtypes. EHD2 is involved in endocytosis and endosomal recycling. This study aimed to investigate the prognostic significance of EHD2 expression in PTC and develop a new model for predicting persistent/recurrent disease after thyroidectomy. Pathologic slides of 512 consecutive patients with PTC ≥ 1 cm were retrospectively reviewed. BRAF mutation analysis and immunohistochemistry for EHD2 were performed. Clinical significance of EHD2 mRNA expression was analyzed in 388 PTC patients using The Cancer Genome Atlas dataset. The presence of dyscohesive cells and psammoma bodies were found have significant association with persistent/recurrent disease (p = 0.049 and p = 0.038, respectively). The best discrimination of disease-free survival was found by dividing patients into three prognostic groups based on the following two risk factors according to the size category: psammoma bodies ≥ 4 and dyscohesive cells (≥ 1% and ≥ 20% in PTCs of < 2.0 cm and ≥ 2.0 cm, respectively). In PTCs of ≥ 2.0 cm, patients with the two risk factors had a hazard ratio of 13.303 (p = 0.005) compared to those without risk factors. High expression level of EHD2 was associated with BRAF V600E (p < 0.001), presence of dyscohesive cells (p = 0.010), and absence of psammoma bodies (p = 0.001). Increased EHD2 mRNA expression level was associated with extrathyroidal extension (p < 0.001), pT3-4 (p < 0.001), lymph node metastasis (p < 0.001), higher risk of recurrence (p < 0.001), and BRAF V600E (p < 0.001). Our prognostic model is useful for predicting persistent/recurrent disease after surgery of PTC. EHD2 mRNA expression could be a novel prognostic marker for PTC patients.

Bidirectional Approach of Video-Assisted Neck Surgery (BAVANS): Endoscopic complete central node dissection with craniocaudal view for treatment of thyroid cancer

INTRODUCTION

Endoscopic thyroidectomy is a well-established surgical technique that is mainly performed for benign thyroid disease. We considered that endoscopic surgery could also be widely indicated for the treatment of thyroid cancer. We herein describe our new bidirectional approach of video-assisted neck surgery (BAVANS) for complete central node dissection in endoscopic thyroid cancer surgery.

METHODS

BAVANS involves two different directional pathways to the cervical lesion. Before lymph node dissection, we perform endoscopic thyroidectomy via a conventional gasless precordial or axillary approach. After thyroidectomy, the surgeon repositions by the head of the patient and inserts three ports in front of the upper neck lesion in the submandibular area to approach the paratracheal lesion from an overhead-to-caudal direction.

RESULTS

BAVANS allows for an excellent craniocaudal view and easy access to the peritracheal lymph nodes. Sixteen patients with papillary thyroid cancer underwent BAVANS and progressed satisfactorily after surgery. Of those patients, eight underwent total or near total thyroidectomy, and five patients underwent bilateral central node dissection. The average number of retrieved lymph nodes with unilateral central node dissection was nine, which was higher than that achieved with conventional open surgery. All patients began oral intake within 5 h after surgery. Postoperative Horner syndrome occurred in one patient. No other complications were noted.

CONCLUSIONS

BAVANS is a very effective surgical procedure that many endoscopic surgeons can perform safely and easily. It has both a cosmetic advantage and excellent curability in endoscopic thyroid cancer surgery.

Cervical intraepithelial neoplasia (CIN) 3-like squamous cell carcinoma of the cervix: a review of 14 cases with comparison of E-cadherin and cyclin D1 expression in the CIN 3-like and infiltrative tumour elements

AIMS

To review the clinicopathological features of 14 cases of CIN 3-like squamous cell carcinoma (SCC) of the cervix and to investigate possible mechanisms of tumour invasion in the CIN 3-like and 'conventional' (infiltrative) tumour components.

METHODS AND RESULTS

The median patient age was 43.4 years. Of the 12 cases with known stage, eight were stage IB and four were stage II. Initial biopsies were often misinterpreted as CIN 3 alone or CIN 3 with only superficial stromal invasion, and eight patients underwent multiple biopsy procedures prior to definitive diagnosis: upon review, an earlier diagnosis was possible in six of these cases. Nine tumours exhibited both CIN 3-like and conventional tumour components. The former usually demonstrated an E-cadherin-positive and cyclin D1-negative immunophenotype, whereas conventional SCC more often showed loss of E-cadherin and cyclin D1 staining at the margin of larger tumour nests and in smaller invasive clusters.

CONCLUSION

Cervical SCCs demonstrating a CIN 3-like growth pattern continue to present diagnostic difficulty and are often misinterpreted as non-invasive/minimally invasive disease. The morphology and immunophenotype suggest a process of collective cellular invasion in CIN 3-like SCC, whereas corresponding conventional SCC elements show features consistent with epithelial-mesenchymal transition.

The incidence and risk factors for central lymph node metastasis in cN0 papillary thyroid microcarcinoma: a meta-analysis

Although there have been many studies identifying clinical and pathologic factors that may predict central lymph node metastases (CLNM) in papillary thyroid microcarcinoma (PTMC) patients without clinically cervical lymph node metastasis (cN0), the results were inconsistent. And whether prophylactic central lymph node dissection (pCLND) should be performed in cN0 PTMC remains controversial. The EMBASE, PubMed, MEDLINE and the Cochrane Library were searched until Oct 2015 to identify relevant studies. Primary outcomes were clinical and pathologic factors for CLNM. Secondary outcomes included CLNM rate, surgical complications of hypocalcaemia and recurrent laryngeal nerve(RLN) injury and neck recurrences. Statistical analysis was performed using Stata 12.0. Fourteen eligible studies enrolling 4573 patients were included in this meta-analysis. The overall incidence of CLNM was 33 % (95 % CI 29-37). An elevated risk of CLNM was significantly associated with male gender (OR 2.33, 95 % CI 1.71-3.17), age <45 years (OR 1.27, 95 % CI 1.08-1.48), tumor size >5 mm (OR 2.16, 95 % CI 1.87-2.50), multifocality (OR 1.73, 95 % CI 1.45-2.05), extrathyroidal extension (OR 1.99, 95 % CI 1.66-2.37) and lymphovascular invasion (OR 3.87, 95 % CI 1.64-9.10), but not with thyroid bilaterality (OR 1.41, 95 % CI 0.89-2.22) and chronic lymphocytic thyroiditis (OR 0.98, 95 % CI 0.66-1.47). The pooled frequency of permanent hypocalcaemia, permanent RLN injury and neck recurrences was 1.1, 0.5 and 2.8 %, respectively. cN0 PTMC patients have a considerable CLNM rate and have a low pooled incident of surgical complications and neck recurrences with pCLND. Six unfavorable clinical and pathologic factors, which were significantly associated with CLNM, were identified. These findings may help guide the application of pCLND or subsequent treatment in cN0 PTMC.

Associations between BRAF(V600E) and prognostic factors and poor outcomes in papillary thyroid carcinoma: a meta-analysis

Background

The objective of this study is to perform a meta-analysis to evaluate the associations between the BRAF^V600E mutation status and aggressive clinicopathological features and poor prognostic factors in papillary thyroid cancer.

Methods

A literature search was performed within the PubMed, MEDLINE, Web of Science databases, and EMBASE databases using the Medical Subject Headings and keywords from January 2003 to July 2015. Individual study-specific odds ratios and confidence intervals were calculated, as were the Mantel-Haenszel pooled odds ratios for the combined studies.

Results

Sixty-three studies of 20,764 patients were included in the final analysis. Compared with wild-type BRAF, the BRAF^V600E mutation was associated with aggressive clinicopathological factors, including extrathyroidal extension, higher TNM stage, lymph node metastasis, and recurrence, and was associated with reduced overall survival; however, there was no significant association between the presence of BRAF mutation and distant metastasis.

Conclusions

BRAF mutations are closely associated with aggressive clinicopathological characteristics and poorer prognosis in papillary thyroid cancer. Accordingly, aggressive treatment should be considered for papillary thyroid cancer patients with BRAF mutation.

Prediction of cervical lymph node metastasis in patients with papillary thyroid cancer using combined conventional ultrasound, strain elastography, and acoustic radiation force impulse (ARFI) elastography

OBJECTIVES

To investigate the value of combined conventional ultrasound (US), strain elastography (SE) and acoustic radiation force impulse (ARFI) elastography for prediction of cervical lymph node metastasis (CLNM) in papillary thyroid cancer (PTC).

METHODS

A consecutive series of 203 patients with 222 PTCs were preoperatively evaluated by US, SE, and ARFI including virtual touch tissue imaging (VTI) and virtual touch tissue quantification (VTQ). A multivariate analysis was performed to predict CLNM by 22 independent variables. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance.

RESULTS

Multivariate analysis demonstrated that VTI area ratio (VAR) > 1 was the best predictor for CLNM, followed by abnormal cervical lymph node (ACLN), capsule contact, microcalcification, capsule involvement, and multiple nodules (all P < 0.05). ROC analyses of these characteristics showed the areas under the curve (Az), sensitivity, and specificity were 0.600-0.630, 47.7 %-93.2 %, and 26.9 %-78.4 % for US, respectively; and they were 0.784, 83.0 %, and 73.9 %, respectively, for VAR > 1. As combination of US characteristics with and without VAR, the Az, sensitivity, and specificity were 0.803 and 0.556, 83.0 % and 100.0 %, and 77.6 % and 11.2 %, respectively (P < 0.001).

CONCLUSIONS

ARFI elastography shows superior performance over conventional US, particularly when combined with US, in predicting CLNM in PTC patients.

KEY POINTS

• Conventional ultrasound is useful in predicting cervical lymph node metastasis preoperatively. • Virtual touch tissue imaging area ratio is the strongest predicting factor. • Predictive performance is markedly improved by combining ultrasound characteristics with VAR. • Acoustic radiation force impulse elastography may be a promising complementary tool.

BRAF(V⁶⁰⁰E) mutation and its association with clinicopathological features of papillary thyroid microcarcinoma: A meta-analysis

Recent studies have demonstrated that the BRAF(V600E) mutation is associated with aggressive clinicopathological features of papillary thyroid carcinoma (PTC). However, the BRAF mutation as a prognostic biomarker in papillary thyroid microcarcinoma (PTMC) is unclear. A systematic search of the electronic databases, including Medline, Scopus, CNKI and the Cochrane Library was performed up to July 1, 2014. Outcomes of interest included age, gender, concomitant hashimoto thyroiditis or nodular goiter, tumor size, pathological stage, tall cell variant of PTMC (TCVPTMC), multifocality, extrathyroidal extension (ETE) and lymph node metastasis (LNM). A total of 19 studies published from 2008 to 2014 comprising 2253 patients fulfilled the inclusion criteria and were included in the meta-analysis, and 1143 (50.7%) of these patients were BRAF mutation positive. BRAF mutation was associated with larger tumor size (OR: 1.64; 95% CI: 1.16-2.32), multifocality (OR: 1.58; 95% CI: 1.25-2.00), ETE (OR: 2.59; 95% CI: 2.03-3.29), LNM (OR: 1.73; 95% CI: 1.14-2.62), advanced stage (OR: 2.03; 95% CI: 1.14-3.64) and TCVPTMC (OR: 5.07; 95% CI: 1.49-17.27; P=0.009). Additionally, the BRAF mutation was found to be not associated with age, gender, concomitant hashimoto thyroiditis or nodular goiter (P>0.05 for all). This meta-analysis revealed that in patients with PTMC, BRAF mutation is associated with tumor size, multifocality, ETE, LNM, advanced stage and TCVPTMC, and it may be used as a predictive factor for prognosis of PTMC.

Prophylactic central lymph node dissection in cN0 patients with papillary thyroid carcinoma: A retrospective study in China

OBJECTIVE

The objective of the study was to assess the patterns of central cervical lymph node metastasis (CLNM) and evaluate the prophylactic central lymph node dissection (CLND) in papillary thyroid carcinoma (PTC) patients without clinical positive lymph nodes.

METHODS

We retrospectively reviewed 1555 patients with PTC between 2003 and 2008. Lymph node metastatic risk factors and the pattern of lymph node metastasis in PTC were studied using multivariate analysis.

RESULTS

Male patients, aged ≤ 45 years, the presence of extrathyroidal extension, and a primary tumor size > 10 mm were identified as risk factors for CLNM with odds ratios of 2.089, 2.417, 1.534, and 3.079, respectively. Among 1555 patients, 97 cases (6.24%) had transient hypoparathyroidism, and only two patients (0.13%) had permanent hypoparathyroidism. Recurrent laryngeal nerve injury after thyroidectomy occurred in 14 patients (0.9%). In this group, nine cases were transient injury and the remaining five were permanent. During the period of follow-up, ranging from 5 years to 10 years, 18 patients (1.16%) were found with locoregional recurrence.

CONCLUSION

Taken together, in terms of the high incidence rate of CLNM in cN0 PTC patients, we believe that routine prophylactic CLND is optimal for clinically negative PTC patients, during their first treatment, especially for those with risk factors for CLNM.

BRAFV600E mutation in papillary thyroid microcarcinoma: a meta-analysis

The prognostic value of the BRAFV600E mutation, resulting in poor clinical outcomes of papillary thyroid carcinoma, has been generally confirmed. However, the association of BRAFV600E with aggressive clinical behaviors of papillary thyroid microcarcinoma (PTMC) has not been firmly established in individual studies. We performed this meta-analysis to examine the relationship between BRAFV600E mutation and the clinicopathological features of PTMC. We conducted a systematic search in PubMed, EMBASE, and the Cochrane library for relevant studies. We selected all the studies that reported clinicopathological features of PTMC patients with information available on BRAFV600E mutation status. Nineteen studies involving a total of 3437 patients met these selection criteria and were included in the analyses. The average prevalence of the BRAFV600E mutation was 47.48%, with no significant difference with respect to patient sex (male versus female) and age (younger than 45 years versus 45 years or older). Compared with the WT BRAF gene, the BRAFV600E mutation was associated with tumor multifocality (odds ratio (OR) 1.38; 95% CI, 1.04-1.82), extrathyroidal extension (OR 3.09; 95% CI, 2.24-4.26), lymph node metastases (OR 2.43; 95% CI, 1.28-4.60), and advanced stage (OR 2.39; 95% CI, 1.38-4.15) of PTMC. Thus, our findings from this large meta-analysis definitively demonstrate that BRAFV600E-mutation-positive PTMC are more likely to manifest with aggressive clinicopathological characteristics. In appropriate clinical settings, testing for the BRAFV600E mutation is likely to be useful in assisting the risk stratification and management of PTMC.

Investigating the association between polymorphisms in connective tissue growth factor and susceptibility to colon carcinoma

There have been numerous studies on the gene expression of connective tissue growth factor (CTGF) in colorectal cancer, however very few have investigated polymorphisms in this gene. The present study aimed to determine whether single nucleotide polymorphisms (SNPs) in the CTGF gene are associated with a higher susceptibility to colon cancer and/or an invasive tumor growth pattern. The CTGF gene was genotyped for seven SNPs (rs6918698, rs1931002, rs9493150, rs12526196, rs12527705, rs9399005 and rs12527379) by pyrosequencing. Formalin-fixed paraffin-embedded tissue samples (n=112) from patients diagnosed with colon carcinoma, and an equal number of blood samples from healthy controls, were selected for genomic DNA extraction. The complexity index was measured using images of tumor samples (n=64) stained for cytokeratin-8. The images were analyzed and correlated with the identified CTGF SNPs and clinicopathological parameters of the patients, including age, gender, tumor penetration, lymph node metastasis, systemic metastasis, differentiation and localization of tumor. It was demonstrated that the frequency of the SNP rs6918698 GG genotype was significantly associated (P=0.05) with an increased risk of colon cancer, as compared with the GC and CC genotypes. The other six SNPs (rs1931002, rs9493150, rs12526196, rs12527705, rs9399005 and rs12527379) exhibited no significant difference in the genotype and allele frequencies between patients diagnosed with colon carcinoma and the normal healthy population. A trend was observed between genotype variation at rs6918698 and the complexity index (P=0.052). The complexity index and genotypes for any of the studied SNPs were not significantly correlated with clinical or pathological parameters of the patients. These results indicate that the rs6918698 GG genotype is associated with an increased risk of developing colon carcinoma, and genetic variations at the rs6918698 are associated with the growth pattern of the tumor. The present results may facilitate the identification of potential biomarkers of the disease in addition to drug targets.

Quantification of BRAF V600E alleles predicts papillary thyroid cancer progression

The BRAF V600E mutation is the most common genetic alteration in thyroid cancer. However, its clinicopathological significance and clonal mutation frequency remain unclear. To clarify the inconsistent results, we investigated the association between the allelic frequency of BRAF V600E and the clinicopathological features of classic papillary thyroid carcinoma (PTC). Tumour tissues from two independent sets of patients with classic PTC were manually microdissected and analysed for the presence or absence of the BRAF mutation and the mutant allelic frequency using quantitative pyrosequencing. For external validation, the Cancer Genome Atlas (TCGA) data were analysed. The BRAF V600E mutation was found in 264 (82.2%) out of 321 classic PTCs in the training set. The presence of BRAF V600E was only associated with extrathyroidal extension and the absence of thyroiditis. In BRAF V600E-positive tumours, the mutant allelic frequency varied from 8 to 41% of the total BRAF alleles (median, 20%) and directly correlated with tumour size and the number of metastatic lymph nodes. Lymph node metastases were more frequent in PTCs with a high (≥20%) abundance of mutant alleles than in those with a low abundance of mutant alleles (P=0.010). These results were reinforced by validation dataset (n=348) analysis but were not reproduced in the TCGA dataset. In a population with prevalent BRAF mutations, quantitative analysis of the BRAF mutation could provide additional information regarding tumour behaviour, which is not reflected by qualitative analysis. Nonetheless, prospective studies are needed before the mutated allele percentage can be considered as a prognostic factor.

Fascin and cyclin D1 immunoreactivity in non-neoplastic vulvar squamous epithelium, vulvar intraepithelial neoplasia and invasive squamous carcinoma: correlation with Ki67 and p16 protein expression

AIMS

To investigate cyclin D1 and fascin immunoreactivity in normal, reactive and neoplastic vulvar skin correlating the findings with p16 protein and Ki67 expression.

METHODS

66 vulvar biopsy or resection specimens demonstrating normal appearances, reactive epidermal changes, usual-type vulvar intraepithelial neoplasia (uVIN), differentiated-type VIN (dVIN), p16-positive squamous cell carcinoma (SCC) and p16-negative SCC were examined immunohistochemically for cyclin D1, fascin, Ki67 and p16 protein. Where applicable, expression patterns were compared in microanatomically distinct areas, particularly at the invasive front (deep tumour margin) of SCC.

RESULTS

Normal epidermis showed parabasal Ki67 and cyclin D1 staining while fascin labelled cells in the lower one-third of the epithelium. Reactive and dVIN specimens demonstrated mildly increased Ki67 and cyclin D1 expression that maintained parabasal polarity, whereas uVIN and p16-positive SCC were characterised by loss of cyclin D1 staining. However, in 14 of 20 p16-positive SCC small infiltrative tumour groups and single infiltrating cells at the invasive front showed a cyclin D1-positive/ Ki67-negative phenotype. In contrast, p16-negative SCC generally showed diffuse and concordant cyclin D1 and Ki67 labelling, including at the invasive margin. Fascin expression was increased in all VIN and SCC lesions.

CONCLUSIONS

Variations in cyclin D1 and Ki67 expression between p16-positive and p16-negative vulvar SCCs suggest different mechanisms of invasion in these tumour subgroups. Fascin is upregulated in vulvar squamous neoplasia but immunostaining does not discriminate in situ from invasive lesions nor putative human papilloma virus (HPV)-associated and HPV-independent SCCs.

Characteristic tumor growth patterns as novel histomorphologic predictors for lymph node metastasis in papillary thyroid carcinoma

The aim of this study was to investigate the efficaciousness of histological tumor growth patterns in the prediction of lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC). All combinations of infiltrative tumor border, lateral tubular growth, and intraglandular dissemination were assessed for their ability to predict LNM in 229 patients. In addition, we analyzed their predictive value within subgroups based on the tumor size and number of tumor nodules. Each tumor growth pattern was significantly associated with LNM, as 11 of the 12 combinations of these 3 patterns were found to be independently predictive of LNM (P < .05). Similar results were observed in both univariate and multivariate logistic regression analyses of PTCs, grouped according to the tumor size and number of tumor nodules. This study has shown that histological features suggestive of invasive tumor growth, including infiltrative tumor border and lateral tubular growth, may be used as independent predictive factors of LNM in PTC, and can improve treatment and follow-up strategies for PTC.

Cyclin D1, E-cadherin and beta-catenin expression in FIGO Stage IA cervical squamous carcinoma: diagnostic value and evidence for epithelial-mesenchymal transition

AIMS

Immunohistochemistry is helpful in distinguishing cervical neoplastic lesions from their histological mimics, but has contributed less towards the sometimes problematic distinction of in-situ and superficially invasive tumours. Epithelial-mesenchymal transition (EMT) may be a mechanism of invasion in cervical neoplasia and expression of EMT-associated proteins could prove useful in this diagnostic setting.

METHODS AND RESULTS

Immunohistochemical expression of cyclin D1, E-cadherin and beta-catenin was assessed in 22 biopsy specimens from FIGO Stage IA cervical squamous carcinomas, all of which also included foci of cervical intraepithelial neoplasia (CIN) 3, nine biopsies of CIN 3 adjacent to carcinoma, and 10 cases of CIN 3 only. Most invasive tumour cells expressed cyclin D1 and showed a reduction in E-cadherin and beta-catenin staining. Nuclear beta-catenin expression was not observed. Cyclin D1 staining was reduced or showed altered distribution in most cases of CIN 3, while adhesion protein expression generally was preserved. However, altered protein expression similar to that of invasion was seen in some CIN lesions.

CONCLUSIONS

Most superficially invasive cervical squamous carcinomas show immunophenotypical changes consistent with EMT. These alterations, particularly cyclin D1 expression, may be useful diagnostically. Similar changes in CIN 3 lesions may indicate the acquisition of increased invasive potential.

BRAF V600E mutation and its association with clinicopathological features of papillary thyroid cancer: a meta-analysis

BACKGROUND

There is conflicting literature regarding the association of the BRAF V600E mutation and aggressive clinicopathological features of papillary thyroid cancer (PTC). Nevertheless, some propose that BRAF status be incorporated into the management of patients with PTC, specifically recommendations regarding lymph node dissection. We therefore performed a meta-analysis to examine the relationship between BRAF and clinicopathological features of PTC.

METHODS

A literature search was performed within PubMed and EMBASE databases using the following Medical Subject Headings (MeSH) and keywords: "braf," "mutation," "thyroid," "neoplasm(s)," "tumor," "cancer," and "carcinoma." Individual study-specific odds ratios and confidence intervals were calculated, as were Mantel-Haenszel pooled odds ratios for the combined studies.

RESULTS

Thirty-two studies including 6372 patients were reviewed. BRAF mutation was associated with lymph node metastases (LNM), advanced stage, extrathyroidal extension, tumor size, male gender, multifocality, absence of capsule, classic PTC, and tall-cell variant PTC. There was no association with age or vascular invasion. Only two studies were prospective; nine included consecutive patients, whereas one included randomly selected patients; and only two included patients who had undergone routine central lymph node dissection and were thus evaluable for the presence of LNM.

CONCLUSION

Meta-analysis found that BRAF mutation is associated with LNM, stage, extrathyroidal extension, tumor size, male gender, multifocality, absence of capsule, classic PTC, and tall-cell variant PTC in PTC. However, almost all studies were retrospective and only two of 32 included patients who had undergone routine central lymph node dissection, emphasizing the need for well-designed studies to appropriately examine this association before making important clinical decisions.

BRAF mutation in papillary thyroid cancer and its value in tailoring initial treatment: a systematic review and meta-analysis

Clinicians have long sought to characterize biological markers of neoplasia as objective indicators of tumor presence, pathogenicity, and prognosis. Armed with data that correlate biomarker activity with disease presence and progression, clinicians can develop treatment strategies that address risks of disease recurrence or persistence and progression. The B-type Raf kinase (BRAF V600E) mutation in exon 15 of the BRAF gene has been noted to be a putative prognostic marker of the most prevalent form of thyroid cancer, papillary thyroid cancer (PTC)--a tumor type with high proclivity for recurrence or persistence. There has been a remarkable interest in determining the association of BRAF mutation with PTC recurrence or persistence. Using many new studies that have been published recently, we performed a meta-analysis to investigate correlations of BRAF mutation status with PTC prognosis, focusing on the recurrence or persistence of the disease after initial treatment. The study was based on published studies included in the PubMed and Embase databases addressing the BRAF mutation and the frequency of recurrence of PTC. We selected studies with data that enabled measurement of the risk ratio for recurrent disease. We also analyzed the factors that are classically known to be associated with recurrence. These factors included lymph node metastasis, extrathyroidal extension, distant metastasis, and American Joint Committee on Cancer (AJCC) stages III/IV. We used 14 articles that included an analysis of these factors as well as PTC recurrence data, with a total of 2470 patients from 9 different countries. The overall prevalence of the BRAF mutation was 45%. The risk ratios in BRAF mutation-positive patients were 1.93 (95% confidence interval [CI], 1.61-2.32; Z = 7.01; p < 0.00001) for PTC recurrence, 1.32 (95% CI, 1.20-1.45; Z = 5.73; p < 0.00001) for lymph node metastasis, 1.71 (95% CI, 1.50-1.94; Z = 8.09; p < 0.00001) for extrathyroidal extension, 0.95 (95% CI, 0.63-1.44; Z = 0.23; p = 0.82) for distant metastasis, and 1.70 (95% CI, 1.45-1.99; Z = 6.46; p < 0.00001) for advanced stage AJCC III/IV. Thus, in this meta-analysis, the BRAF mutation in PTC was significantly associated with PTC recurrence, lymph node metastasis, extrathyroidal extension, and advanced stage AJCC III/IV. Patients with PTC harboring mutated BRAF are likely to demonstrate factors that are associated with an increased risk for recurrence of the disease, offering new prospects for optimizing and tailoring initial treatment strategies to prevent recurrence.

BRAF mutation detection in indeterminate thyroid cytology specimens: underlying cytologic, molecular, and pathologic characteristics of papillary thyroid carcinoma

BACKGROUND

BRAF mutations are highly specific for papillary thyroid carcinoma (PTC) and many cytology specimens with BRAF mutations are expected to demonstrate cytologic features typical of PTC. However, indeterminate thyroid cytology cases are inevitable and understanding the significance of the BRAF mutation within the context of the Bethesda System for Reporting Thyroid Cytopathology would be valuable.

METHODS

Thyroid cytology cases submitted for conventional cytomorphologic evaluation and BRAF mutational analyses were selected from the authors' cytopathology files from April 2007 to October 2011. From this group, the diagnostic usefulness of BRAF mutations in indeterminate and malignant cases was assessed and analyses of cytologic and histopathologic features associated with the mutations in this gene were performed.

RESULTS

A total of 131 cases with a BRAF mutation were identified. Of these, 119 underwent surgical pathology resection follow-up and demonstrated PTC. Approximately 75% of the cases were cytologically diagnosed as being positive for malignancy and these cases were associated with both the classic and tall cell variants of PTC at the time of resection, a greater likelihood of extrathyroidal extension, and the V600E type of BRAF mutation. In contrast, BRAF-mutated cases with diagnoses of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) and follicular neoplasm/suspicious for follicular neoplasm were found to be more strongly associated with the follicular variant of PTC, a K601E BRAF mutation, and a lower likelihood of extrathyroidal extension. However, a subset of AUS/FLUS cases with the V600E BRAF mutation appeared to represent sampling variability of the classic or tall cell variants of PTC.

CONCLUSIONS

Bethesda thyroid diagnoses in the setting of a BRAF mutation reflect differences in PTC subtypes, the nature of cytology specimens, and molecular characteristics.

Mutational patterns and novel mutations of the BRAF gene in a large cohort of Korean patients with papillary thyroid carcinoma

BACKGROUND

BRAF mutation is the most common genetic event in papillary thyroid carcinoma (PTC); however, the prevalence and patterns of the mutation vary worldwide. We investigated the frequency and type of BRAF mutations based on the histologic subtypes in a large cohort of Korean patients with PTC.

METHODS

A total of 1041 consecutive PTCs were classified according to histologic subtypes. BRAF mutations were examined by denaturing high-performance liquid chromatography and direct sequencing. Rare complex mutations were confirmed by molecular cloning of polymerase chain reaction amplicons and sequencing of the products.

RESULTS

BRAF mutations were found in 839 (80.6%) of 1041 patients with PTC. The histologic subtype-specific prevalence of BRAF mutation was as follows: 85.3% (249/292) were classic, 45.8% (11/24) were follicular, 79.9% (576/721) were microcarcinoma, and 75.0% (3/4) were other variants. In addition to the usual c.1799T>A mutation, we identified other four mutation types: c.[1795_1796insA;1770_1795dup26], c.[1742-10T>C;1799T>A] and c.[1796C>G;1799T>A], and c.1799_1800TG>AA, respectively. The former three were novel mutations in thyroid tumors. Within the series of microcarcinoma variants, the BRAF mutation rate was lower in tumors with follicular morphology than those with nonfollicular types (66.7% vs. 80.9%, p=0.0145).

CONCLUSION

Out of 1041 Korean patients with PTC, 0.4% had rare types of BRAF mutation and three new somatic mutations were identified. The BRAF mutation rate was quite low in PTC with follicular morphology regardless of tumor size. However, the prevalence of BRAF mutation in microcarcinoma and follicular variants of PTC is relatively high in Korea and its analysis may be clinically useful for managing the patients.

Papillary thyroid carcinomas with cervical lymph node metastases can be stratified into clinically relevant prognostic categories using oncogenic BRAF, the number of nodal metastases, and extra-nodal extension

BACKGROUND

Papillary thyroid carcinoma (PTC) patients presenting with cervical lymph nodes (LN) metastases (M) have a variable outcome. The objective of this study is to assess the value of meticulous histopathologic examination and genotyping in stratifying these patients into clinically relevant prognostic subgroups.

METHODS

This was a retrospective clinical and histopathological review of PTC patients with lymph node metastases at presentation identified between 1980 and 2002 in a single institution. Primary tumors from patients who later recurred were matched to a group of patients who did not recur and subjected to mass spectrometry genotyping encompassing the most significant oncogenes in thyroid carcinomas.

RESULTS

There were 246 patients who satisfied the inclusion criteria. The median follow-up was 10.8 years. The presence of >3 metastatic nodes was an independent predictor of decreased recurrence free survival (p=0.03). In patients <45 years, none of 45 with 1-2 metastatic LN recurred, including 26 patients followed for a median of 13 years without radioactive iodine (RAI) therapy. BRAF mutations were found in 28 (78%) of 36 genotyped tumors. Combined positivity for BRAF and extra-nodal extension was much stronger in predicting disease specific survival (DSS) (p=0.004) than the single analysis of BRAF (p=0.12) or extra-nodal extension (p=0.02).

CONCLUSIONS

(i) The number of metastatic LN is an independent predictor of recurrence in all age groups and identifies a subset of young patients with excellent prognosis who may not benefit from RAI therapy. (ii) Combined positivity for BRAF and extra-nodal extension has additive prognostic value in predicting DSS. (iii) Classification systems that assign the same magnitude of risk for recurrence or death to all patients with N1 disease should be revisited.

American Thyroid Association consensus review and statement regarding the anatomy, terminology, and rationale for lateral neck dissection in differentiated thyroid cancer

BACKGROUND

Cervical lymph node metastases from differentiated thyroid cancer (DTC) are common. Thirty to eighty percent of patients with papillary thyroid cancer harbor lymph node metastases, with the central neck being the most common compartment involved. The goals of this study were to: (1) identify appropriate methods for determining metastatic DTC in the lateral neck and (2) address the extent of lymph node dissection for the lateral neck necessary to control nodal disease balanced against known risks of surgery.

METHODS

A literature review followed by formulation of a consensus statement was performed.

RESULTS

Four proposals regarding management of the lateral neck are made for consideration by organizations developing management guidelines for patients with thyroid nodules and DTC including the next iteration of management guidelines developed by the American Thyroid Association (ATA). Metastases to lateral neck nodes must be considered in the evaluation of the newly diagnosed thyroid cancer patient and for surveillance of the previously treated DTC patient.

CONCLUSIONS

Lateral neck lymph nodes are a significant consideration in the surgical management of patients with DTC. When current guidelines formulated by the ATA and by other international medical societies are followed, initial evaluation of the DTC patient with ultrasound (or other modalities when indicated) will help to identify lateral neck lymph nodes of concern. These findings should be addressed using fine-needle aspiration biopsy. A comprehensive neck dissection of at least nodal levels IIa, III, IV, and Vb should be performed when indicated to optimize disease control.

The Wnt/β-catenin pathway drives increased cyclin D1 levels in lymph node metastasis in papillary thyroid cancer

We examined the expression of cyclin D1 in conjunction with β-catenin and the phosphorylated inactive form of glycogen synthase kinase 3β (GSK-3β) in benign, nonneoplastic thyroid tissue as well as papillary thyroid carcinoma primary tumors and nodal metastases. We aim to unravel the regulation of cyclin D1 and determine if this cell cycle protein is a useful biomarker for metastatic disease. It is clear that expression of cyclin D1 (P < .0001), β-catenin (P < .0001), and inactive form of GSK-3β (P < .0001) are significantly higher in papillary thyroid carcinoma primary tumors than in corresponding benign, nonneoplastic tissue thyroid specimens. Interestingly, β-catenin and cyclin D1 expressions in papillary thyroid carcinoma are correlated (P = .025), implying that β-catenin is a factor driving higher levels of cyclin D1 consistent with previous cell models linking Wnt/β-catenin signaling and cyclin D1 expression. Conversely, inactive form of GSK-3β expression does not correlate with cyclin D1 (P = .52) or β-catenin expression (P = .54). We also did not observe any relationship between tumor size and marker expression. Comparing papillary thyroid carcinoma primary tumors with or without nodal metastases, we did not see any differences in expression of inactive form of GSK-3β (P = .95), β-catenin (P = .14), or cyclin D1 (P = .46). However, in papillary thyroid carcinoma lymph node specimens, the up-regulation of cyclin D1 (P = .0083) was highly significant compared with primary tumors. pGSK-3β and β-catenin expression did not vary between primary tumors and nodal specimens. In conclusion, we have demonstrated that expression of cyclin D1 is linked to nodal metastases and that cyclin D1 levels are regulated by Wnt/β-catenin signaling. GSK pathway-mediated regulation of β-catenin or cyclin D1 expression does not appear operative in papillary thyroid carcinoma.

K-ras mutations are correlated to lymph node metastasis and tumor stage, but not to the growth pattern of colon carcinoma

In colorectal carcinoma, pathological assessment of tumors is essential for determining therapy and prognosis of the disease. Molecular associations of tumor complexity index and genetic alternations can be helpful to understand the tumor progression mechanism. Oncogenic K-ras is one of the major colorectal cancer associated genes, and is mutated in up to 50% of colorectal cancers. In this current study, we correlated tumor complexity index with mutations in K-ras codon 12, 13, and 61 in association with different clinicopathological parameters such as TNM stage, localization, sex, and age. Formalin-fixed paraffin embedded tissue blocks from colon cancer samples was selected from 88 patients diagnosed with adenocarcinoma. Mutations in the K-ras gene were detected using pyrosequencing technique. Tumor complexity index was calculated using immunohistochemically stained images of the tumor outline of the specimens and then analyzing these pictures using Photoshop CS, Fovea Pro, and Image J computer programs. Statistical analysis was performed with SPSS. K-ras mutations were detected in 17 (19.3%) colon cancer samples. Most of the samples were at a lower complexity index. No correlation was observed between K-ras mutations and complexity index. However, K-ras mutations were correlated with regional lymph node metastasis and tumor stages and complexity index with tumor wall penetration. In conclusion, complexity index and K-ras mutations are independent events; however, both correlate with tumor progression and are important in the biologic development of colon carcinoma.