Prospective multicenter study of thyroiscarcinoma treatment: initial analysis of staging and outcome. National Thyroid Cancer Treatment Cooperative Study Registry Group

A pilot study of serum selenium, vitamin D, and thyrotropin concentrations in patients with thyroid cancer

BACKGROUND

Low serum selenium concentrations have been associated with a diagnosis of differentiated thyroid cancer in small studies in selenium deficient areas. We conducted a pilot study to explore associations between selenium concentrations and the diagnosis of thyroid cancer in an area of selenium sufficiency in the United States. As low 25-hydroxyvitamin D concentrations have been associated with several malignancies, we also examined 25-hydroxyvitamin D levels.

METHODS

This study was designed as a pilot study of prediagnostic selenium and 25-hydroxyvitamin D concentrations. We identified 65 euthyroid patients at an academic medical center who were scheduled for thyroidectomy for thyroid cancer, suspicion of thyroid cancer, or nodular disease. Blood samples were obtained two to four weeks prior to thyroidectomy. Samples were analyzed for thyrotropin (TSH), free thyroxine, total triiodothyronine, selenium, and 25 hydroxyvitamin D levels. Concentrations of these analytes were correlated with whether the patient was diagnosed with benign or malignant disease following their thyroidectomy. In patients with thyroid cancer, the concentrations of selenium and 25-hydroxyvitamin D were correlated with various prognostic features.

RESULTS

Although selenium concentrations were not significantly lower in patients with thyroid cancer, serum selenium concentrations were inversely correlated with disease stage (p = 0.011). There were no associations between vitamin D concentration and a diagnosis of thyroid cancer. Within the thyroid cancer patients, vitamin D concentrations were not associated with disease stage or any other prognostic features. In contrast, TSH concentrations were significantly higher in patients with thyroid cancer, and were positively correlated with the number of involved lymph nodes (p = 0.011) and disease stage (p = 0.022).

CONCLUSION

These data confirm the association between serum TSH and advanced thyroid cancer. In addition, they also suggest a potential association between selenium concentrations and higher thyroid cancer stage. No such association was seen for 25-hydroxyvitamin D concentrations. Larger prospective studies will be required to confirm this association. If confirmed, future studies would need to determine if the association is causative in nature. If causation exists, it seems likely that selenium concentrations would influence thyroid cancer development via an independent mechanism from that of TSH.

BRAF mutation and RASSF1A expression in thyroid carcinoma of southern Italy

Aim of this work is to provide a detailed comparison of clinical-pathologic features between well-differentiated and poorly differentiated tumors according to their BRAF and RASSF1A status. We analyzed RASSF1A methylation by MSP and BRAF mutation by LCRT-PCR with LightMix® kit BRAF V600E in neoplastic thyroid tissues. Immunohistochemical evaluation of RASSF1A expression was also performed by standard automated LSAB-HRP technique. An overall higher degree of RASSF1A over-expression than normal thyroid parenchyma surrounding tumors (P < 0.05) has been found in all malignant well-differentiated lesions. Moreover, statistically significant higher levels of RASSF1A expression were observed in differentiated cancers associated to an inflammatory autoimmune background (P = 0.01). Amplifiable DNA for LC PCR with LightMix® kit BRAF V600E was obtained in nine PTCs, four FVPTCs, five ATCs, and one control. The V600E mutation was found in 13 of 18 (72%) tumors. BRAF was mutated in 6 of 9 (66%) classical PTC, in 2 of 4 (50%) follicular variant PTC and in all ACs (100%). The overall frequency of RASSF1A promoter methylation observed was 20.5% (9 cases out 44). Hypermethylation of RASSF1A in primary tumors was variable according to histotypes ranging from100% (5/5) in ACs to only 12.5% (4/32) in PTCs. We show a correlation between RASSF1A methylation status and RASSF1A protein expression. Finally, we conclude that BRAF V600E mutation and RASSF1A methylation were pathogenetic event restricted to a subgroup of PTC/FVPTCs in early stage and to clinically aggressive ATCs.

Results of the Thyroid Cancer Alliance international patient/survivor survey: Psychosocial/informational support needs, treatment side effects and international differences in care

OBJECTIVE

To comprehensively assess the experience of a large, diverse cohort and identify potential care improvements, the Thyroid Cancer Alliance, an international patient/survivor group coalition, surveyed thyroid cancer patients/survivors worldwide.

DESIGN

English, German, French or Spanish versions of a self-developed 43-item questionnaire were completed, predominantly online, by 2398 respondents from the US (37.9%), Germany (21.3%), the UK (11.5%), Canada (11.4%), France (9%), and 35 other countries. Females and differentiated thyroid carcinoma patients each comprised ~87% of respondents. Diagnosis occurred at age 30-59 years in 71.8%, within <1 (1-5) year(s) before survey completion in 16.4% (55%).

RESULTS

At diagnosis, no psychological (or other professional) support was offered to 92.6% (76.9%) of respondents, no patient organization referral was made to 84.1%, and no clear written disease/treatment information was given to 63%. The five leading care improvement suggestions involved increased informational/psychosocial support. Among respondents undergoing neck surgery pre-survey completion (n = 2380), 72.5% reported at least transient complications, including hypocalcemia (38.8%), voice problems (36.2%), numbness (28.7%), or restricted neck/shoulder movement (27.6%).

CONCLUSIONS

This large, multinational, patient/survivor-initiated cross-sectional survey suggests that thyroid cancer patients/survivors have substantial unmet informational/psychosocial support needs and suffer frequent treatment morbidity; disease management and some patient/survivor experience differ appreciably among countries.

RAC1b overexpression in papillary thyroid carcinoma: a role to unravel

CONTEXT

The BRAF V600E mutation is the most frequent genetic alteration in papillary thyroid carcinoma (PTC). In colorectal cancer, BRAF V600E was described to functionally cooperate with RAC1b, a hyperactive splice variant of the small GTPase RAC1, to sustain cell survival. This interplay has never been investigated in PTCs.

OBJECTIVE

We aimed to analyze the expression of RAC1b in PTC and correlate its expression with BRAF V600E mutational status, histopathological features, and clinical outcome.

PATIENTS AND METHODS

Sixty-one patients and 87 samples (61 PTCs and 26 normal thyroid tissues) were included. Patients were divided into two groups based on longitudinal evolution and final outcome. RAC1b expression levels were determined by quantitative RT-PCR and western blotting.

RESULTS

RAC1b was expressed in thyroid and overexpressed in 46% of PTCs. Neither RAC1b overexpression nor V600E mutation correlated with histopathological features classically associated with worse prognosis. RAC1b overexpression was significantly associated with both V600E mutation (P=0.0008) and poor clinical outcome (P=0.0029). Whereas BRAF V600E alone did not associate with patient outcome (P=0.2865), the association of RAC1b overexpression with BRAF V600E was overrepresented in the group with poorer clinical outcome (P=0.0044).

CONCLUSIONS

Present results document, for the first time, expression of RAC1b in normal thyroid cells as well as overexpression in a subset of PTCs. Furthermore, they suggest a possible interplay between BRAF V600E and RAC1b contributing to poor clinical outcome. Future studies are needed to clarify the oncogenic potential of RAC1b in thyroid carcinogenesis.

Pitfalls in the staging of cancer of thyroid

Thyroid cancer includes several neoplasms originating from the thyroid gland-from indolent and curable histologies of differentiated thyroid carcinoma to aggressive anaplastic thyroid carcinoma. Differentiation of thyroid nodules is problematic on CT and MR imaging unless there is evidence of extrathyroidal extension. Evaluation of regional lymph nodes is often performed clinically or with ultrasound. The retropharyngeal and mediastinal lymph nodes are better evaluated by CT and MR imaging. Nuclear scintigraphy is useful for staging and treatment of distant metastasis in differentiated thyroid carcinoma. PET may have a role in aggressive cancers. Accurate staging affects surgical management and subsequent therapy.

Comparison with published systems of a new staging system for papillary and follicular thyroid carcinoma

BACKGROUND

Several staging systems exist to estimate the prognosis for patients with thyroid carcinoma. Our goal was to develop a new staging system to predict cancer-specific survival (CSS) and evaluate it against published systems.

METHODS

The Cedars-Sinai Medical Center (CSMC)'s staging system was derived using data from an adjusted analysis of 1622 patients with differentiated thyroid carcinomas (DTCs) from the CSMC Thyroid Cancer Center. Mean follow-up time was 11.8 years. There were 1180 female and 442 male patients with a mean age of 46. Staging systems reviewed include University of Alabama (Birmingham) and M.D. Anderson Cancer Center (UAB-MDACC); the Tumor-Node-Metastasis (TNM) 5th and 7th editions; Memorial Sloan-Kettering (MSK); the National Thyroid Cancer Treatment Cooperative Study (NTCTCS); Ohio State; Clinical Class; Metastases, Age, Completeness of resection, Invasion, and tumor Size (MACIS); Noguchi; and the Yildirim model for predicting outcomes. The proportion of variance explained (PVE) and the C-index were computed to rank and compare each staging system's ability to predict CSS with this patient population.

RESULTS

Adjusted hazard ratios revealed that age at surgery of >45 years, the presence of distant metastases, capsular invasion, and vascular invasion were the most significant predictors of CSS in this patient population. The final CSMC risk score consists of low-, moderate-, and high-risk groups. Among the well-differentiated thyroid carcinoma staging systems, the CSMC and NTCTCS ranked highest with PVE values of 5% and 4.3%, respectively, while the NTCTCS and CSMC staging systems were reversed using the C-index (0.77 and 0.76, respectively).

CONCLUSION

The PVE and C-index values were relatively low across all applicable staging systems and varied in each study reviewed. This suggests that no one staging system has been shown to be superior to another across different patient populations with DTC. In the future, additional factors, such as biological markers, added to the clinical and pathological characteristics may lead to the development of superior staging systems.

Pathological characteristics and clinical perspectives of papillary thyroid cancer: study of 714 patients

Papillary thyroid cancer belongs to most commonly diagnosed well-differentiated malignant tumor of the thyroid gland, with only minority of cases being more aggressive, recurring locoregionally and developing distant metastatic foci. The aim of this study was to determine the clinical relationship between parameters of age, gender, size of primary tumor, intraglandular dissemination and regional metastatic spread and evaluate the importance of each parameter; analyze other major aggressive factors (tumor border, thyroid capsule invasion, perivascular, perilymphatic spread) on prevalence and extent of intraglandular dissemination and relation to metastatic spread in neck. This study is a retrospective analysis of clinical and pathological data from 714 patients with papillary thyroid cancer, presented and operated at the Department of ENT/Head and Neck surgery, Sisters of Charity University Hospital, Zagreb, in the period from 1980 to 2008. All patients were operated upon with total thyroidectomy and some type of neck lymphonode dissection (paratracheal or lateral). In results, we found 46.9% tumors were aggressive; 34.7% tumors were multicentric, with foci in the contralateral lobe nearly twice as often as in the ipsilateral lobe; 27.8% were regionally metastatic, with equal distribution between paratracheal and lateral regions. In conclusion, we revealed contralateral lobe multicentricity and male gender as independent risk factors for regional metastatic dissemination. Nodular goiter has been identified as a protective parameter.

Lymph node ratio predicts recurrence in papillary thyroid cancer

BACKGROUND

Lymph node metastasis occurs in 20%-50% of patients presenting for initial treatment of papillary thyroid cancer (PTC). The significance of lymph node metastases remains controversial, and the aim of this study is to determine how the lymph node ratio (LNR) may predict the likelihood of disease recurrence.

METHODS

We conducted a retrospective review of patients undergoing total thyroidectomy for PTC at our institution from 2005 to 2010. A total LNR (positive nodes to total nodes) and central lymph node ratio (cLNR) was calculated. Regression was used to determine a threshold LNR that best predicted recurrence. Multivariate logistic regression then determined the influence of LNR on recurrence while accounting for other known predictors of recurrence. Kaplan-Meier analysis and the log-rank test were used to compare differences in disease-free survival.

RESULTS

Of the 217 patients undergoing total thyroidectomy for PTC, 69 patients had concomitant neck dissections. Sixteen (23.2%) patients developed disease recurrence. When disease-free survival functions were compared, we found that patients with a total LNR ≥0.7 (p < .01) or a cLNR ≥0.86 (p = .04) had significantly worse disease-free survival rates than patients with ratios below these threshold values. Considering other known predictors of recurrence, we found that LNR was significantly associated with recurrence (odds ratio: 19.5, 95% confidence interval: 4.1-22.9; p < .01).

CONCLUSIONS

Elevated total LNR and cLNR are strongly associated with recurrence of PTC after initial operation. LNR in PTC is a tool that can be used to determine the likelihood of the patient developing recurrent disease and inform postoperative follow-up.

Clinical prognostic index for recurrence of papillary thyroid carcinoma including intraoperative findings

This study created a new staging system using a risk model that employed clinical factors that were associated with recurrence, verified by preoperative clinical information and intraoperative finding and was compared with other staging systems. A review was conducted of patients who have undergone thyroidectomy and followed-up between January 1, 1983 and September 31, 2007 at Yonsei University Wonju Christian Hospital. The final prognostic staging system was defined as University of Yonsei clinical staging system (Prognostic score = 0.03 × Age + 0.8 × (if male gender) + 0.5 × (if extrathyroidal tumor extension present) + 0.7 × (if clinically apparent lymph node metastasis present), Stage I, less than 1.50; Stage II, 1.50 to 2.29; Stage III, 2.30 to 3.29; Stage IV 4, 3.3 or more). Compared with the other staging systems, the proportion of variation explained (PVE %) was calculated for each. The University of Yonsei clinical staging system appeared to be first as an accurate prognosis predictor with 11.9%. New staging system can predict recurrence and has advantage can use preoperative clinical information and intraoperative finding. Those who are diagnosed as high risk patients using the new staging system should be treated with aggressive surgical treatment and close follow-up.

Impact of lymph node ratio on survival in papillary thyroid cancer

BACKGROUND

In papillary thyroid cancer, the role of lymph node dissection remains controversial, and staging systems consider metastatic lymph nodes as a binary entity. The purpose of this study was to determine a threshold lymph node ratio (LNR) that impacted disease-specific mortality (DSM).

METHODS

We utilized the surveillance, epidemiology, and end results (SEER) database to analyze adult patients who underwent thyroidectomy with lymph node dissection. A LNR (metastatic lymph nodes to total lymph nodes) was calculated after eliminating patients with less than three nodes collected. Kaplan-Meier estimates for DSM were plotted for LNRs and compared by the log rank test. The Cox proportional hazards model was used to evaluate LNR with other known clinical and pathologic determinants of prognosis.

RESULTS

A total of 10,955 cases contained data on lymph nodes. Median follow-up time was 25 months (range 0-59 months), and the mean LNR was 0.28 ± 0.37. After comparing Kaplan-Meier survival estimates and overall DSM rates, we found that a LNR ≥0.42 best divided those with lymph node metastasis based on DSM (p < 0.01). Those with a LNR ≥0.42 experienced a DSM rate of 1.72 % while those with a LNR <0.42 had a DSM rate of 0.65 % (p < 0.01). In addition, patients with a LNR ≥0.42 experienced a 77 % higher DSM rate compared to those with metastatic lymph nodes as a whole. When considered with other known determinants of prognosis, we found that LNR was strongly associated with DSM (hazard ratio 4.33, 95 % confidence interval 1.68-11.18, p < 0.01).

CONCLUSIONS

LNR is a strong determinant of DSM, and a threshold LNR of 0.42 can be used to risk-stratify patients with metastatic lymph nodes.

Absence of galectin-3 immunostaining in fine-needle aspiration cytology specimens from papillary thyroid carcinoma is associated with favorable pathological indices

BACKGROUND

Galectin-3 (G3) immunostaining of fine-needle aspiration (FNA) samples from thyroid nodules is very useful for the diagnosis of malignancy. The objective of the present study was to determine whether the absence of G3 immunostaining in preoperative FNA samples is associated with favorable clinicopathological parameters, including lymph node (LN) metastasis, in papillary thyroid carcinoma (PTC).

METHODS

The records of 868 patients with PTC who had prethyroidectomy ultrasonography-guided FNA with G3 immunostaining between January 2006 and December 2009 were retrospectively reviewed. G3 immunostaining was considered positive if the percentage of tumor cells showing definite cytoplasmic immunostaining exceeded 5%. Patients who had negative G3 immunostaining of FNA samples were assigned to the G3-negative (G3N) group; whereas those who had positive G3 immunostaining were assigned to the G3-positive (G3P) group.

RESULTS

There were 92 patients who were assigned to the G3N group (10.6%) because of the negative staining for G3 in the preoperative FNA samples from their thyroid nodules. The proportion of PTC subtypes in the G3N and G3P groups was similar (p=0.376). There was less frequent thyroid capsular invasion (46.7% vs. 66.5%, p<0.001), extrathyroidal extension (28.3% vs. 48.5%, p<0.001), and LN metastasis (22.2% vs. 48.7%, p<0.001) in the G3N group than the G3P group. In multivariate regression analysis, G3N expression predicted a lower risk of LN metastasis (odds ratio=0.37, 95% confidence interval 0.18-0.78) after adjustment for other clinicopathological parameters. Over a median follow-up of 33 months, no association was observed between G3N and disease-free survival.

CONCLUSION

The absence of G3 expression in FNA samples from PTC is associated with pathological parameters considered less aggressive than is the case for PTCs with G3 expression, including being a negative predictor of negative LN involvement. Long-term follow-up studies, however, are needed to verify whether G3N patients have lower recurrence and mortality rates.

Adequacy of pathology reports of specimens from patients with differentiated thyroid cancer

This study aims to investigate the adequacy of pathology reports of specimens from patients with differentiated thyroid cancer (DTC) operated in our institution. Retrospective analysis of the pathology reports of all patients diagnosed with DTC in our area, from 1 January 2006 through 30 June 2011, was done. Sixty-eight patients were diagnosed with DTC. All reports were descriptive. In all the reports, but one, one or more core data items (according to the Royal College of Pathologists) were missing. Information about 1 and 2 items was lacking in 7.4 and 42.6 % of the reports, respectively. The rest were missing three or more data. Lymphovascular invasion, histology subtype, and completeness of excision were, in this order, the three most frequently omitted data. Sometimes, the information in question was not explicitly expressed but could be extrapolated from the data available. The pathology reports of DTC specimens frequently miss some of the information considered necessary to provide a comprehensive patient care.

Surgical decision making in the management of well-differentiated thyroid cancer

The incidence of thyroid cancer in the United States has been increasing. The biologic behavior of well-differentiated thyroid cancer (WDTC) can vary from indolent tumor to an aggressive disease with invasion of critical structures and/or widespread distant metastasis. Therefore, the risk stratification is crucial in understanding the biology of thyroid cancer, its prognosis and appropriate therapeutic interventions. In fact, understanding the nuances of biological behavior of thyroid carcinomas lays the foundation for the idea of selective surgical management of this disease.

Radioactive iodine-refractory differentiated thyroid cancer: unmet needs and future directions

Approximately 90% of thyroid cancers are differentiated (DTCs) and have papillary, follicular or Hürthle cell morphology. Although treatment with surgery and radioactive iodine (I-131; RAI), as appropriate, is associated with significant cure rates and survival benefits, clonal disease progression with development of refractoriness to RAI poses a major therapeutic challenge in about 15% of patients. Traditional chemotherapeutic agents are relatively ineffective and are associated with significant toxicities. Molecular studies have demonstrated that the development and progression of DTC are associated with a series of consistent abnormalities in pathways such as MAPK/ERK and PI3/Akt, which govern cellular growth, proliferation, apoptosis and angiogenesis. Small molecular inhibitors that target these pathogenic pathways, without many of the impairments associated with cytotoxic chemotherapy, have demonstrated efficacy in a variety of malignancies, including renal cell carcinoma, hepatocellular carcinoma, non-small-cell lung cancer and chronic myelogenous leukemia. Several targeted therapeutic agents are in development for the treatment of RAI-refractory DTC. Sorafenib and lenvatinib are being studied in placebo-controlled Phase III trials based on encouraging efficacy results observed in single-arm Phase II studies.

Density of tumor-associated macrophages correlates with lymph node metastasis in papillary thyroid carcinoma

BACKGROUND

Tumor-associated macrophages (TAMs) have recently been recognized as being important players in the tumoriogenesis of many cancers, including advanced thyroid cancer. However, a role in papillary thyroid carcinoma (PTC), the most prevalent thyroid cancer, has not been established. We hypothesized that TAMs also facilitate tumor progression in PTC.

METHODS

We investigated TAMs density in both benign thyroid lesions and PTC tumors by CD68 immunostaining. CD68-positive cell density was further associated with the clinicopathological characteristics of PTC patients. Finally, TAMs were isolated from PTC tumors and phenotyped by cytokine and receptor profiling.

RESULTS

The overall density of TAMs was found to be significantly higher in PTC tumors, compared with thyroid goiter and follicular adenoma. The density of TAMs was positively associated with lymph node metastasis in TNM (tumor-node-metastasis) stages III/VI compared with stages I/II. No association was observed in other common tumor features, including the BRAF mutation. The isolated TAMs presented with high levels of M2-associated cytokine and receptors, making M2 the predominant TAM phenotype.

CONCLUSIONS

TAMs may play a functional role in the progression of PTC.

The impact of age and gender on papillary thyroid cancer survival

CONTEXT

Thyroid cancer predominately affects women, carries a worse prognosis in older age, and may have higher mortality in men. Superimposed on these observations is the fact that most women have attained menopause by age 55 yr.

OBJECTIVE

The objective of the study was to determine whether men contribute disproportionately to papillary thyroid cancer (PTC) mortality or whether menopause affects PTC prognosis.

DESIGN

Gender-specific mortality was normalized using age-matched subjects from the U.S. population. Multivariate Cox proportional hazard regression models incorporating gender, age, and National Thyroid Cancer Treatment Cooperative Study Group stage were used to model disease-specific survival (DSS).

PARTICIPANTS AND SETTING

Patients were followed in a prospective registry.

MAIN OUTCOME MEASURE

The relationships between gender, age, and PTC outcomes were analyzed.

RESULTS

The unadjusted hazard ratio (HR) for DSS for women was 0.40 [confidence interval (CI) 0.24-0.65]. This female advantage diminished when DSS was adjusted for age at diagnosis and stage with a HR encompassing unity (HR 0.72, CI 0.44-1.19). Additional multivariate models of DSS considering gender, disease stage, and various age groupings showed that the DSS for women diagnosed at under 55 yr was improved over men (HR 0.33, CI 0.13-0.81). However, the HR for DSS increased to become similar to men for women diagnosed at 55-69 yr (HR 1.01, CI 0.42-2.37) and at 70 yr or greater (HR 1.17, CI 0.48-2.85).

CONCLUSIONS

Although the overall outcome of women with PTC is similar to men, subgroup analysis showed that this composite outcome is composed of two periods with different outcomes. The first period is a period with better outcomes for women than men when the diagnosis occurs at younger than 55 yr; the second is a period with similar outcomes for both women and men diagnosed at ages greater than 55 yr. These data raise the question of whether an older age cutoff would improve current staging systems. We hypothesize that older age modifies the effect of gender on outcomes due to menopause-associated hormonal alterations.

BRAFV600E mutation in fine-needle aspiration aspirates: Association with poorer prognostic factors in larger papillary thyroid carcinomas

BACKGROUND

Recent studies have shown that BRAF(V600E) mutation is associated with poor prognostic factors in papillary thyroid carcinoma (PTC). However, there are no studies about the association of the BRAF(V600E) mutation with poor prognostic factors according to tumor size in PTC.

METHODS

We investigated the prevalence of the BRAF(V600E) mutation and its association with prognostic factors according to tumor size of PTC. BRAF(V600E) mutation status was assessed in thyroid fine-needle aspiration (FNA) specimens from 605 patients before thyroidectomy for PTC, and its association with postoperative clinicopathologic factors was evaluated.

RESULTS

The overall prevalence of the BRAF(V600E) mutation was 67%, and larger tumors more often had the BRAF(V600E) mutation (p for trend < .05). The BRAF(V600E) mutation was significantly associated with male sex, tumor size, extrathyroidal invasion, nodal metastasis, and advanced tumor stage (p < .05). There was a significant size-dependent relationship between the presence of the BRAF(V600E) mutation and extrathyroidal invasion, nodal metastasis, and advanced tumor stage (p for trend < .05).

CONCLUSION

The prevalence of the BRAF(V600E) mutation increased with increased tumor size. Preoperative FNA-detected BRAF(V600E) mutation was associated with poor prognostic factors, and the association was stronger in larger tumors.

The impact of microscopic extrathyroid extension on outcome in patients with clinical T1 and T2 well-differentiated thyroid cancer

OBJECTIVE

To report the impact of microscopic extrathyroid extension (ETE) on outcome in patients with cT1/cT2 well-differentiated thyroid cancer (WDTC), and to determine the effect of extent of surgery and adjuvant radioactive iodine (RAI) treatment on outcome in patients with microscopic ETE.

PATIENTS AND METHODS

From an institutional database, we identified 984 patients (54%) who underwent surgery for cT1/T2N0 disease. Of these, 869 patients were pT1/T2 and 115 were upstaged to pT3 based on the finding of microscopic ETE. Disease-specific survival (DSS) and recurrence-free survival (RFS) were analyzed for each group using the Kaplan-Meier method. In the pT3 group, factors predictive of outcome were analyzed by univariate and multivariate analyses.

RESULTS

There was no difference in the 10-year DSS (99% vs 100%; P = .733) or RFS (98% vs 95%; P = .188) on comparison of the pT1/pT2 and pT3 cohorts. Extent of surgery and administration of postoperative RAI were not significant for recurrence on univariate or multivariate analysis in the pT3 cohort.

CONCLUSION

Outcomes in patients with cT1T2N0 WDTC are excellent and not affected by microscopic ETE. The extent of resection and administration of postoperative RAI in patients with microscopic ETE does not impact survival or recurrence.

CXCR4 expression correlates with the degree of tumor infiltration and BRAF status in papillary thyroid carcinomas

Emerging evidence indicates that interactions between chemokine receptors and their ligands may have a critical role in several steps of tumor development, including tumor growth, progression, and metastasis. In this report, we retrospectively evaluated CXCR4 expression in a consecutive series of 200 papillary thyroid carcinomas. We investigated the relationship between the clinicopathological features of the tumors and mutations in the BRAF gene to verify whether overexpression of CXCR4 is linked to more aggressive behavior in thyroid tumors. CXCR4 protein expression was evaluated by immunohistochemical staining. A final staining score was calculated by adding the score representing the percentage of positive cells to the intensity score. The CXCR4 expression of each papillary thyroid carcinoma sample was normalized by calculating the z score for each final staining score. Univariate analysis was used to correlate CXCR4 expression with the papillary thyroid carcinoma variant, the degree of neoplastic infiltration, the American Joint Commission on Cancer stage, the presence of lymphocytic thyroiditis and the mutation status of the BRAF gene. Multiple regression analysis confirmed a strong association between CXCR4, BRAF mutation and the degree of neoplastic infiltration. These data clearly indicate that the chemokine receptor expression induced by oncogenic activation could be the major determinant of the local aggressiveness of neoplastic cells. In conclusion, our data indicate that CXCR4 expression and BRAF mutation status could cooperatively induce and promote a more aggressive phenotype in papillary thyroid carcinoma through several pathways and specifically increase the tumors' spread outside of the thyroid gland.

Amplification of thymosin beta 10 and AKAP13 genes in metastatic and aggressive papillary thyroid carcinomas

Papillary thyroid carcinoma (PTC) is the most common well-differentiated thyroid cancer. Although the great majority of the cases exhibit an indolent clinical course, some of them develop local invasion with distant metastasis, and a few cases transform into undifferentiated/anaplastic thyroid carcinoma with a rapidly lethal course. To identify gene copy number alterations predictive of metastatic potential or aggressive transformation, array-based comparative genomic hybridization (CGH-array) was performed in 43 PTC cases. Formalin-fixed and paraffin-embedded samples from primary tumours of 16 cases without metastasis, 14 cases with only regional lymph node metastasis, and 13 cases with distant metastasis, recurrence or extrathyroid extension were analysed. The CGH-array and confirmatory quantitative real-time PCR results identified the deletion of the EIF4EBP3 and TRAK2 gene loci, while amplification of thymosin beta 10 (TB10) and Tre-2 oncogene regions were observed as general markers for PTC. Although there have been several studies implicating TB10 as a specific marker based on gene expression data, our study is the first to report on genomic amplification. Although no significant difference could be detected between the good and bad prognosis cases in the A-kinase anchor protein 13 (AKAP13) gene region, it was discriminative markers for metastasis. Amplification in the AKAP13 region was demonstrated in 42.9% and 15.4% of the cases with local or with distant metastasis, respectively, while no amplification was detected in non-metastatic cases. AKAP13 and TB10 regions may represent potential new genomic markers for PTC and cancer progression.

Weight changes in euthyroid patients undergoing thyroidectomy

BACKGROUND

Thyroidectomized patients frequently report weight gain resistant to weight loss efforts, identifying their thyroidectomy as the event precipitating subsequent weight gain. We wished to determine whether recently thyroidectomized euthyroid patients gained more weight over 1 year than matched euthyroid patients with preexisting hypothyroidism.

METHODS

We performed a retrospective chart review of subjects receiving medical care at an academic medical center. One hundred twenty patients had their weight and thyroid status documented after thyroidectomy and achievement of euthyroidism on thyroid hormone replacement, and one year later. Three additional groups of 120 patients with preexisting hypothyroidism, no thyroid disease, and thyroid cancer were matched for age, gender, menopausal status, height, and weight. Anthropometric data were documented at two time points 1 year apart. We compared the weight changes and body mass index changes occurring over a 1-year period in the four groups.

RESULTS

Patients with recent postsurgical hypothyroidism gained 3.1 kg during the year, whereas matched patients with preexisting hypothyroidism gained 2.2 kg. The patients without thyroid disease and those with iatrogenic hyperthyroidism gained 1.3 and 1.2 kg, respectively. The weight gain in the thyroidectomized group was significantly greater than that in the matched hypothyroid group (p-value 0.004), the group without thyroid disease (p-value 0.001), and the patients with iatrogenic hyperthyroidism (p-value 0.001). Within the thyroidectomized group, the weight gain in menopausal women was greater than in either premenopausal women (4.4 vs. 2.3 kg, p-value 0.007) or men (4.4 vs. 2.5 kg, p-value 0.013).

CONCLUSION

Patients who had undergone thyroidectomy in the previous year did, in fact, gain more weight than their matched counterparts with preexisting hypothyroidism. In addition, all patients with hypothyroidism, even though treated to achieve euthyroidism, experienced more weight gain than both subjects without hypothyroidism and subjects with iatrogenic hyperthyroidism. The greatest weight gain in the thyroidectomized group was in menopausal women. These data raise the question of an unidentified factor related to taking thyroid hormone replacement that is associated with weight gain, with an additional intriguing effect of thyroidectomy itself. Menopausal status confers additional risk. These groups should be targeted for diligent weight loss efforts.

Successful management of differentiated thyroid cancer in a community-based endocrine practice

OBJECTIVE

To describe the range of differentiated thyroid cancer (DTC) cases, disease complexity, and treatment outcomes seen in our 3-physician community-based general endocrine practice during an 8-year period in order to make comparisons with published cohorts from university settings.

METHODS

Medical records of patients with DTC treated between 2002 and 2009 at Mountain Diabetes and Endocrine Center (Asheville, North Carolina) were reviewed. Pathologic features, staging, and disease status at last contact were determined. Multivariate analyses of adverse prognostic risk factors at diagnosis, recombinant human thyroid-stimulating hormone use, and radioiodine use were compared with the ultimate outcome of patients.

RESULTS

We treated a total of 167 patients with DTC during the study period (mean age at diagnosis, 44.4 years; mean duration of follow-up, 6.2 years). In our study cohort, 88.6% had papillary thyroid cancer, 74% had stage I disease, and 32.4% of those with papillary thyroid cancer had microscopic tumors (≤1 cm). Remission occurred in 67.1%, 17.1% had persistent disease, and 11.8% were indeterminate for remission; non-thyroid cancer death occurred in 2.6% and disease-specific death in 1.3%. The mean number of adverse prognostic risk factors per patient was 2.0 in those with remission and 4.7 in those with persistent disease.

CONCLUSION

Community-based endocrinologists evaluate the full spectrum of thyroid cancer disease complexity and can achieve excellent outcomes. In our current study group, disease persistence and disease-specific death occurred in 17.1% and 1.3%, respectively. Individualization of care based on prognostic variables guided our diagnostic and therapeutic decisions.

Thyroid carcinoma in children and adolescents-systematic review of the literature

Thyroid cancer in children and adolescents is usually a major concern for physicians, patients, and parents. Controversies regarding the aggressiveness of the clinical presentation and the ideal therapeutic approach remain among the scientific community. The current recommendations and staging systems are based on data generated by studies in adults, and this might lead to overtreating in some cases as well as undertreating in others. Understanding the differences in the biology, clinical course, and outcomes in this population is crucial for therapeutic decisions. This paper evaluates the biology, clinical presentation, recurrences, and overall survival as well as the staging systems in children and adolescents with differentiated thyroid cancer.

Sentinel lymph node biopsy is unsuitable for routine practice in younger female patients with unilateral low-risk papillary thyroid carcinoma

Background

Sentinel lymph node (SLN) biopsy has been used to assess patients with papillary thyroid carcinoma (PTC). To achieve its full potential the rate of SLN identification must be as close to 100 percent as possible. In the present study we compared the combination of preoperative lymphoscintigraphy scanning by sulfur colloid labeled with 99 m Technetium, gamma-probe guided surgery, and methylene blue with methylene blue, alone, for sentinel node identification in younger women with unilateral low-risk PTC.

Methods

From January 2004 to January 2007, 90 female patients, ages 23 to 44 (mean = 35), with unilateral low-risk PTC (T_1-2N₀M₀) were prospectively studied. Mean tumor size was 1.3 cm (range, 0.8-3.7 cm). All patients underwent unilateral modified neck dissection. Prior to surgery, patients had, by random assignment, identification and biopsy of SLNs by methylene blue, alone (Group 1), or by sulfur colloid labeled with 99 m Technetium, gamma-probe guided surgery and methylene blue (Group 2).

Results

In the methylene blue group, SLNs were identified in 39 of 45 patients (86.7%). Of the 39 patients, 28 (71.8%) had positive cervical lymph nodes (pN+), and 21 patients (53.8%) had pSLN+. In 7 of the 28 pN+ patients (25%), metastases were also detected in non-SLN, thus giving a false-negative rate (FNR of 38.9% (7/18), a negative predictive value (NPV) of 61.1% (11/18), and an accuracy of 82.1% (32/39). In the combined technique group, the identification rate (IR) of SLN was 100% (45/45). Of the 45 patients, 27 (60.0%) had pN+, 24 (53.3%) had pSLN+. There was a FNR of 14.3% (3/21), a NPV of 85.7% (18/21), and an accuracy of 93.3% (42/45). The combined techniques group was significantly superior to the methylene blue group in IR (p = 0.035). There were no significant differences between two groups in sensitivity, specificity, NPV, or accuracy. Location of pN+ (55 patients) in 84 patients was: level I and V, no patients; level II, 1 patient (1.2%); level III, 6 patients (7.2%); level III and IV, 8 patients (9.5%); level IV, alone, 8 patients (9.5%); level VI, 32 patients (38.1%). In all 90 patients, IR of SLN was 93.3%, FNR, 25.6%, NPV, 74.4%, and accuracy rate, 88.1 percent.

Conclusions

Compared to a single technique, there was a significantly higher SLN identification rate for the combined technique in younger female with ipsilateral, low-risk PTC (T_1-2N₀M₀). Thus, a combined SLN biopsy technique seems to more accurately stage lymph nodes, with better identification of SLN located out of the central compartment. Regardless of the procedure used, the high FNR renders the current SLN techniques unsuitable for routine practice. Based on these results, prophylactic node dissection of level VI might be considered because 38.1% of our patients had such node metastases.

Alternative surgical strategies in patients with sporadic medullary thyroid carcinoma: Long-term follow-up

The extent of surgical resection in patients with sporadic medullary thyroid carcinoma (SMTC) remains controversial. The aim of the present study was to discuss the prognosis of sporadic medullary thyroid carcinoma with different surgical treatments. Of 73 patients with SMTC (mean age of 43.78 years at diagnosis), 70 patients were followed up for 12.0-169.0 months (median 90.0). Having given their informed consent, 12 patients underwent total thyroidectomy with bilateral central neck dissection (group A), 40 underwent subtotal thyroidectomy preserving contralateral thyroid tissue on the entrance point of the recurrent laryngeal nerve into the larynx with ipsilateral modified radical neck dissection (group B), and 18 patients underwent subtotal thyroidectomy preserving contralateral thyroid tissue on the entrance point of the recurrent laryngeal nerve into the larynx with bilateral modified radical neck dissection (group C). The diagnosis was confirmed by a pathology examination. The incidences of hypoparathyroidism and recurrent laryngeal nerve injury, the cancer recurrence rates and survival time were investigated post-operatively. Significant differences were found between groups A, B and C in the incidence of hypoparathyroidism (χ(2)=40.9, P<0.01), as well as that of recurrent laryngeal nerve injury (χ(2)=32.9, P<0.01). The cancer recurrence rates in groups A, B and C were 75.0% (9/12), 2.5% (1/40) and 44.4% (8/18) respectively, (χ(2)=31.1, P<0.01) and the cure rates were 25, 97.5 and 55.6% respectively (χ(2)=31.1, P<0.01). The mean survival times in groups A, B and C were 77.8, 106.1 and 111.0 months respectively, but significant difference was noted (χ(2)=3.2, P>0.05). In conclusion, compared to total thyroidectomy with bilateral central neck dissection, subtotal thyroidectomy with ipsilateral/bilateral modified radical neck dissection showed a lower incidence of hypoparathyroidism, recurrent laryngeal nerve injury and lower rates of recurrence, along with a similar cumulative survival.

The association of the BRAF(V600E) mutation with prognostic factors and poor clinical outcome in papillary thyroid cancer: a meta-analysis

BACKGROUND

The effects of the BRAF(V600E) mutation on prognostic factors and poor clinical outcomes in papillary thyroid cancer (PTC) have not been fully quantified. The authors performed comprehensive meta-analysis to assess the strength of associations between these conditions and the BRAF(V600E) mutation.

METHODS

The authors identified the clinical studies that examined the association of the BRAF(V600E) mutation in surgical specimens with clinicopathologic outcomes between January 2003 and October 2010 using the Medline database. One hundred thirty-one relevant studies were hand-searched. The authors selected 27 studies that included 5655 PTC patients. They calculated the pooled odds ratios (ORs) or risk ratios with 95% confidence intervals (CIs) for each study using a random effect model.

RESULTS

The average prevalence rate of the BRAF(V600E) mutation was 49.4%. In 26 studies, compared with the patients who had the wild-type BRAF genes, the PTC patients with the BRAF(V600E) mutation had increased ORs of an extrathyroidal invasion (OR, 2.14; 95% CI, 1.68-2.73), a lymph node metastasis (OR, 1.54; 95% CI, 1.21-1.97), and an advanced TNM stage (OR, 2.00; 95% CI, 1.61-2.49). In 8 studies, patients with the mutation had 2.14-fold increased risk of recurrent and persistent disease (95% CI, 1.67-2.74). The associations were generally consistent across the different study populations.

CONCLUSIONS

This meta-analysis demonstrates that the BRAF(V600E) mutation is closely related to the high-risk clinicopathological factors and poorer outcome of PTC. The results obtained here suggest that the BRAF(V600E) mutation should be considered as a poor prognostic marker in PTC and may lead to better management for individual patients.

Aberrant promoter methylation in overexpression of CITED1 in papillary thyroid cancer

BACKGROUND

More than 80% of all thyroid cancers, the most common endocrine malignancy, are papillary thyroid cancer (PTC). It is well established that CITED1 (Cbp/p300 Interacting Transactivators with glutamic acid [E] and aspartic acid [D]-rich C-terminal domain) mRNA is characteristically overexpressed in PTC. Our previous study suggested a positive association of BRAF mutation with CITED1 overexpression. However, the mechanism of CITED1 expression in PTC remains to be elucidated. In the present study, we analyzed whether aberrant methylation of CITED1 gene promotes CITED1 overexpression in PTC.

METHOD

CITED1 mRNA expression levels were analyzed by quantitative polymerase chain reaction in three PTC-derived cell lines, TPC1, K1, and KTC-1, and in surgically dissected PTC and surrounding normal tissues from 19 patients. The BRAF mutation status of the cells and clinical specimens was determined by direct sequencing. The methylation status of the deoxycitidine-phosphate-deoxyguanosine dinucleotides (CpGs) in the CITED1 promoter was analyzed by the bisulfite-sequencing method using genomic DNA. Finally, the expression of CITED1 mRNA in TPC1 cells, when subjected to pharmacological inhibition of methylation, was analyzed.

RESULTS

CITED1 mRNA was expressed at lower levels in TPC1 than in K1 and KTC-1 cells. A BRAF mutation was present in K1 and KTC-1 cells, but not in TPC1 cells. CITED1 promoter was hypomethylated in K-1 and KTC-1 cells, but not in TPC1 cells. In surgically dissected specimens, the mean expression level of CITED1 mRNA was 30-fold higher in PTC tissues than in normal tissues. CpGs in the CITED1 promoter were more heavily methylated in normal tissues than in PTC tissues. In PTC specimens without a BRAF mutation, two CpGs were more heavily methylated than in PTC specimens with the BRAF V600E mutation. Pharmacological inhibition of methylation in TPC1 cells by 5'-aza-2'-deoxycitidine resulted in increased expression of CITED1 mRNA.

CONCLUSION

Hypomethylation of the CpGs in the promoter region of CITED1 is associated with higher expression of CITED1 mRNA in PTC tissues, consistent with the hypothesis that epigenetic regulation is involved in the overexpression of CITED1. This hypothesis is supported by pharmacologic inhibition studies in TPC1 cells.

Factors determining the persistence or recurrence of well-differentiated thyroid cancer treated by thyroidectomy and/or radioiodine in the Boston, Massachusetts area: A retrospective chart review

OBJECTIVE

To assess predictors of well-differentiated thyroid cancer (WDTC) persistence/recurrence.

DESIGN

This was a retrospective chart review of thyroid carcinoma patients seen 1979-2007 in a Boston, Massachusetts-area multispecialty group. Of 1,025 patients, 431 met eligibility criteria. Cox proportional hazards models were used to assess predictors (gender, age, ethnicity, tumor size, surgical histology) of WDTC persistence/recurrence (elevated thyroglobulin levels with negative thyroglobulin-antibodies; or positive imaging). Local extension of disease and lymph node involvement could not be assessed.

RESULTS

Mean age at initial surgery (n = 431, 74% women, 79% Caucasian) was 45.8 ± 13.5(SD) years. Mean tumor (papillary, 91%; follicular, 5%; Hurthle cell, 2%; ≥1 type, 2%) size was 2.5 ± 1.6(SD) cm. Most tumors were unifocal (57%) and ≥1 cm (89%). Over 2,600 person-years of follow-up, persistence/recurrence occurred in 52 patients (12%) 4.3 years (median; range 0.2-23.2 years) after surgery. Gender, ethnicity, tumor size, multifocality, and histology were not predictive of persistence/recurrence, while older age was predictive in some models.

CONCLUSIONS

In WDTC patients treated by total and near total thyroidectomy and radioiodine and analyzed without consideration of local, locoregional, and distant extent of disease, neither size of tumor nor male gender contribute to disease persistence/recurrence. Age at diagnosis seems to have some positive prognostic value even if only patients older than 21 years at diagnosis are considered. Due to the rare occurrence of follicular (also oxyphilic) histotype, this conclusion refers mainly to patients with papillary thyroid cancer.

Upregulation of endocrine gland-derived vascular endothelial growth factor in papillary thyroid cancers displaying infiltrative patterns, lymph node metastases, and BRAF mutation

BACKGROUND

Endocrine gland-derived vascular endothelial growth factor (Prok1) and prokineticin 2 (Prok2) are involved in the organ-specific regulation of angiogenesis, which is a crucial step toward cancer progression in most tumors, including those of thyroid gland. The oncogene BRAF V600E mutation is associated with poor clinical outcome of papillary thyroid cancer (PTC) and can independently predict its recurrence.

DESIGN

Our hypothesis was that Prok1 and Prok2 expression levels associated with BRAF mutations can be prognostic factors for PTC outcome. Prok1 and Prok2 were examined in PTC, a cell line derived from a human PTC (designated FB-2), euthyroid multinodular goiter (MNG), Graves' disease (GD), and contralateral normal thyroid (NT) tissues from PTC cases. We evaluated BRAF mutation and its relationship with Prok1 expression pattern in PTC.

METHODS

We studied Prok1 and Prok2 mRNAs by real-time polymerase chain reaction and BRAF mutation by mutant allele-specific polymerase chain reaction amplification. Formalin-fixed, paraffin-embedded blocks of PTC and NT were used for the immunohistochemical determination of Prok1 using anti-endocrine gland vascular endothelial growth factor primary antibody.

RESULTS

Prok1 and Prok2 transcripts were both present in thyroid tissues, and Prok1 was differentially expressed in PTC compared to MNG, GD, and NT. Prok1 mRNA levels were very low in NT and MNG and significantly higher in PTC, FB-2, and GD (p<0.05). Prok1 protein was almost undetectable in NT but was highly expressed in all PTC samples having an infiltrative pattern of growth and lymph node metastases ( p<0.05). Further, the expression of Prok1 in PTC was associated with 60% of the samples being positive for the BRAF mutation ( p<0.05).

CONCLUSIONS

We found that Prok1 is significantly increased in PTC, and its expression in PTC is related to BRAF mutation. These results suggest that Prok1 could be a new useful marker for thyroid cancer progression. Prok1 therefore could also be a potential target for novel therapeutic strategies, although the lack of functional data suggests caution against generalization of this assumption

Actin filament associated protein mediates c-Src related SRE/AP-1 transcriptional activation

AFAP is an adaptor protein involved in cytoskeletal organization and intracellular signaling. AFAP binds and activates c-Src; however, the downstream signals of this interaction remain unknown. Here we show that co-expression of AFAP and c-Src induce transcriptional activation of SRE and AP-1 in a c-Src activity dependent fashion. Structural-functional studies suggest that the proline-rich motif in the N-terminus of AFAP is critical for c-Src activation, and subsequent SRE/AP-1 transactivation and the actin-binding domain in the AFAP C-terminus is negatively involved in the regulation of AFAP/c-Src mediated SRE/AP-1 transactivation. Selective deletion of this domain enhances transactivation of SRE. We conclude that in addition to its role in the regulation of cytoskeletal structures, AFAP may also be involved in the c-Src related transcriptional activities.

XB130, a novel adaptor protein, promotes thyroid tumor growth

Adaptor proteins with multimodular structures can participate in the regulation of various cellular functions. We have cloned a novel adaptor protein, XB130, which binds the p85α subunit of phosphatidyl inositol 3-kinase and subsequently mediates signaling through RET/PTC in TPC-1 thyroid cancer cells. In the present study, we sought to determine the role of XB130 in the tumorigenesis in vivo and in related molecular mechanisms. In WRO thyroid cancer cells, knockdown of XB130 using small interfering RNA inhibited G(1)-S phase progression, induced spontaneous apoptosis, and enhanced intrinsic and extrinsic apoptotic stimulus-induced cell death. Growth of tumors in nude mice formed from XB130 shRNA stably transfected WRO cells were significantly reduced, with decreased cell proliferation and increased apoptosis. Microarray analysis identified 246 genes significantly changed in XB130 shRNA transfected cells. Among them, 57 genes are related to cell proliferation or survival, including many transcription regulators. Ingenuity Pathway Analysis showed that the top-ranked disease related to XB130 is cancer, and the top molecular and cellular functions are cellular growth and proliferation and cell cycle. A human thyroid tissue microarray study identified expression of XB130 in normal thyroid tissue as well as in human thyroid carcinomas. These observations suggest that the expression of XB130 in these cancer cells may affect cell proliferation and survival by controlling the expression of multiple genes, especially transcription regulators.

Estimating risk of recurrence in differentiated thyroid cancer after total thyroidectomy and radioactive iodine remnant ablation: using response to therapy variables to modify the initial risk estimates predicted by the new American Thyroid Association staging system

BACKGROUND

A risk-adapted approach to management of thyroid cancer requires risk estimates that change over time based on response to therapy and the course of the disease. The objective of this study was to validate the American Thyroid Association (ATA) risk of recurrence staging system and determine if an assessment of response to therapy during the first 2 years of follow-up can modify these initial risk estimates.

METHODS

This retrospective review identified 588 adult follicular cell-derived thyroid cancer patients followed for a median of 7 years (range 1-15 years) after total thyroidectomy and radioactive iodine remnant ablation. Patients were stratified according to ATA risk categories (low, intermediate, or high) as part of initial staging. Clinical data obtained during the first 2 years of follow-up (suppressed thyroglobulin [Tg], stimulated Tg, and imaging studies) were used to re-stage each patient based on response to initial therapy (excellent, acceptable, or incomplete). Clinical outcomes predicted by initial ATA risk categories were compared with revised risk estimates obtained after response to therapy variables were used to modify the initial ATA risk estimates.

RESULTS

Persistent structural disease or recurrence was identified in 3% of the low-risk, 21% of the intermediate-risk, and 68% of the high-risk patients (p < 0.001). Re-stratification during the first 2 years of follow-up reduced the likelihood of finding persistent structural disease or recurrence to 2% in low-risk, 2% in intermediate-risk, and 14% in high-risk patients, demonstrating an excellent response to therapy (stimulated Tg < 1 ng/mL without structural evidence of disease). Conversely, an incomplete response to initial therapy (suppressed Tg > 1 ng/mL, stimulated Tg > 10 ng/mL, rising Tg values, or structural disease identification within the first 2 years of follow-up) increased the likelihood of persistent structural disease or recurrence to 13% in low-risk, 41% in intermediate-risk, and 79% in high-risk patients.

CONCLUSIONS

Our data confirm that the newly proposed ATA recurrence staging system effectively predicts the risk of recurrence and persistent disease. Further, these initial ATA risk estimates can be significantly refined based on the assessment of response to initial therapy, thereby providing a dynamic risk assessment that can be used to more effectively tailor ongoing follow-up recommendations.

The BRAF mutation is predictive of aggressive clinicopathological characteristics in papillary thyroid microcarcinoma

BACKGROUND

This study analyzed the utility of BRAF mutation screening of ultrasonography-guided fine-needle aspiration biopsy (FNAB) specimens for predicting aggressive clinicopathological characteristics of papillary thyroid microcarcinoma (PTMC).

METHODS

We assessed the T1799A BRAF mutation status in FNAB specimens obtained from 61 PTMC patients before undergoing operations for PTMC. We examined whether the BRAF mutation was associated with clinicopathologic characteristics in PTMC. Additionally, we reviewed the BRAF mutation status, and clinical, ultrasound (US), hematological, and pathology records of the patients and analyzed the associations between these characteristics and lateral lymph node metastasis (LNM).

RESULTS

Analysis of the preoperative FNABs accurately reflected the BRAF status of the resected tissues in 19 of the 20 paired samples (95% concordance). We observed that the BRAF mutation was statistically significantly associated with multifocality, extrathyroidal invasion, lateral LNM, and advanced tumor stages III and IV. The BRAF mutation, pathologic features (central LNM), and US features (upper pole location) were independent predictive factors for lateral LNM in a multivariate analysis with odds ratios of 18.144 (95% confidence interval [95% CI], 1.999-164.664; P = 0.01), 8.582 (95% CI, 1.014-76.662; P = 0.049) and 9.576 (95% CI, 1.374-66.728; P = 0.023), respectively.

CONCLUSIONS

BRAF mutation-positive PTMCs were more likely to manifest aggressive characteristics (extrathyroidal extension and LNM). The BRAF mutation screening of FNAB specimens can be used to predict aggressive clinicopathological characteristics of PTMC. Lateral neck nodes should be meticulously analyzed for cases of PTMC demonstrating the following three characteristics: BRAF mutation, central LNM, and US features in the upper pole location.

Primary tumour size is a prognostic parameter in patients suffering from differentiated thyroid carcinoma with extrathyroidal growth: results of the MSDS trial

OBJECTIVE

The Multicentre Study Differentiated Thyroid Cancer (MSDS) collective represents a well-defined group of patients with thyroid carcinomas with extrathyroidal extension. The aim of the present study was to evaluate the relationship of the primary tumour size with clinicopathological features as well as the outcome of patients with minimum and extensive extrathyroidal growth (pT3b- and pT4a-tumours; UICC 2002/2003, 6th ed).

METHODS

The tumour diameter was available in 324 out of 351 MSDS patients (244 females, 80 males). Mean age of patients was 47.7±12.0 years (range, 20.1-69.8 years), and the median follow-up was 6.2 years. The relationship between primary tumour size and the following clinicopathological data was investigated: age, gender, histological tumour type (papillary thyroid carcinomas (PTC) versus follicular thyroid carcinomas (FTC)) and UICC/AJCC TNM classification. In addition, the correlation between primary tumour size and event-free and overall survival was assessed.

RESULTS

The FTC of our series were significantly larger than PTC (3.46 vs 1.84 cm; P<0.001). Patients suffering from pT3b-tumours presented with significantly smaller tumour size than those with extensive extrathyroidal growth (pT4a-tumours) (1.9 vs 3.0 cm; P<0.01). All patients with distant metastases suffered from tumours >2 cm. Furthermore, event-free and overall survival were significantly correlated with increasing tumour size (P<0.05). Using multivariate analysis, a pT4a-category and a tumour diameter >2 cm remained independent predictors of survival.

CONCLUSIONS

In patients suffering from differentiated thyroid carcinoma with extrathyroidal growth (pT3b and pT4a), the tumour size is an independent predictor of event-free and overall survival.

Inhibition of uPAR and uPA reduces invasion in papillary thyroid carcinoma cells

OBJECTIVES/HYPOTHESIS

We analyzed the expression of urokinase plasminogen activator (uPA) and its receptor (uPAR) in papillary thyroid carcinoma (PTC) and normal thyroid tissue and examined in vitro how uPA and uPAR contribute to an invasive/metastatic phenotype, and the functional consequences of inhibiting this system.

STUDY DESIGN

Retrospective chart review of PTC patients, followed by prospective study using previously obtained patient tissue and PTC cellular models.

METHODS

uPA and uPAR RNA and protein levels were analyzed in PTC patient tissue samples, PTC and normal thyroid tissue culture cells, and conditioned media (CM) using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and/or Western blotting. The plasminogen-activating ability of CM was examined using dark-quenched casein fluorimetry and casein-plasminogen gel zymography. The invasive potentials of the PTC and normal thyroid epithelial cell lines were assessed using an in vitro cellular invasion/migration system.

RESULTS

uPA and uPAR RNA and protein levels were increased in PTC patient samples and PTC cells relative to controls. uPA and uPAR RNA were also significantly higher in patients with metastatic disease. Casein-plasminogen zymography and Western blotting demonstrated increased active uPA secreted by PTC cells compared with normal thyroid cells. Fluorimetric assays revealed that the PTC cells' CM was able to activate plasminogen, resulting in measurable casein hydrolysis. This casein hydrolysis was prevented by the addition of several specific uPA inhibitors. Finally, the in vitro invasion phenotypes of PTC cells were augmented by the addition of plasminogen, and this augmentation was reversed by inhibitory anti-uPA and anti-uPAR antibodies.

CONCLUSIONS

These data provide new functional evidence of the uPA/uPAR system's role in PTC invasion/metastasis and demonstrate the attractiveness of uPA and uPAR as molecular biomarkers and therapeutic targets.

Thyroid cancer epidemiology and prognostic variables

Thyroid cancer comprises a broad spectrum of diseases with variable prognoses. Although most patients with this disease have excellent overall survival, there are some who do not fare so well. With the worldwide increase in incidence, the need to identify which tumours pose the greatest risk to patients is more acute than ever. This paper will discuss this rising trend in incidence with an analysis of the possible reasons for the increase. In addition, the paper will explore the factors that portend a worse prognosis for the individual patient. Finally, the limitations of the current staging systems will be discussed, with particular emphasis on why they are not as informative in the management of patients with thyroid cancer.

A comparison of prognostic classification systems for differentiated thyroid carcinoma

OBJECTIVE

To identify and compare prognostic classification systems based on basic tumour characteristics that were developed and/or validated for differentiated thyroid carcinoma (DTC).

DESIGN

Retrospective chart study.

METHODS

Literature was studied using PubMed. Fifteen different prognostic classification systems were identified, of which seven were developed or validated for DTC patients and were based on basic tumour characteristics. These systems were applied to 1225 DTC patients who were treated in our hospital between 1978 and 2002.

RESULTS

Log-rank analysis of Kaplan-Meier cancer-specific survival curves showed that the curve of the Tumor, Lymph-Node, Metastasis (TNM) system had the greatest discriminatory power (log-rank test, log P = -84.9). Cox-regression analysis showed that the TNM system was the most powerful determinant of cancer-specific survival curves. Proportion of variance explained (PVE) analysis showed that the TNM system had the highest PVE.

CONCLUSION

Of the prognostic classification systems analysed in this study, the TNM system performs best in all the three analyses, and is therefore the most suitable for predicting outcome in DTC-patients.

Old and new insights in the treatment of thyroid carcinoma

Thyroid cancer is the endocrine tumor that bears the highest incidence with 33 550 new cases per year. It bears an excellent prognosis with a mortality of 1530 patients per year (Jemal et al.; 2007). We have been treating patients with thyroid carcinoma during many years without many innovations. Recently, we have assisted to the development of new agents for the treatment of this disease with unexpected good results. Here we present a review with the old and new methods for the treatment of this disease.

Inhibition of mTORC1 signaling reduces tumor growth but does not prevent cancer progression in a mouse model of thyroid cancer

Selective drugs targeting dysregulated oncogenic pathways are promising cancer therapies. Because the mammalian target of rapamycin complex 1 (mTORC1) pathway is hyperactivated in human follicular thyroid cancer (FTC), we hypothesized that its inhibition could block cancer development and progression. We, therefore, analyzed the effect of a treatment with a specific mTORC1 inhibitor (RAD001) in a faithful mouse model of FTC with constitutive mTORC1 activation (TRbeta(PV/PV)Pten(+/-) mice). The treatment did not prevent capsular and vascular invasion of the thyroid and the occurrence of lung metastasis. However, it substantially decelerated thyroid tumor growth, thereby prolonging TRbeta(PV/PV)Pten(+/-) mouse life span. RAD001 efficiently inhibited mTORC1 activity, as shown by the reduced phosphorylation of its downstream targets involved in the activity of the translation machinery, such as ribosomal S6 kinase (p70(S6K)), eukaryotic translation initiation factor 4E binding protein (4E-BP1) and the eukaryotic translation initiation factors eIF-4B and eIF-4G. Whereas mTORC1 signaling inhibition did not alter cell apoptosis, it induced a significant decrease in cell proliferation that was associated with the reduced abundance and altered activity of key regulators of cell cycle progression. Altogether, our data indicate that mTORC1 signaling plays a major role in the integration of the mitogenic signal in FTC. Therefore, our preclinical study with a relevant mouse model of FTC demonstrates for the first time that RAD001 efficaciously stabilizes cancer growth although it does not prevent its fatal outcome. In conclusion, our work underscores that in the treatment of FTC patients, RAD001 can only be used in combination with drugs and therapies inducing tumor shrinkage and blocking metastasis.

Approach to the thyroid cancer patient with extracervical metastases

Patients with distant, or extracervical, metastases from differentiated thyroid cancer require multimodality diagnostic, therapeutic, and monitoring approaches. Whereas cure is the initial goal, especially in those with small, radioiodine-avid pulmonary metastases, improved survival and management of symptoms become the primary objective in many patients with persistent disease, especially those with bone metastases. Levothyroxine therapy with suppression of serum TSH is a primary therapy in all patients with advanced differentiated thyroid cancer, and this therapy has been shown to improve overall survival and slow disease progression. Radioiodine is also an important systemic therapy for those patients with radioiodine-avid disease who respond to this targeted therapy. In this review, we compare standard fixed-dose radioiodine therapy vs. the dosimetric approach. Directed therapy such as external beam radiotherapy, surgery, and embolization is generally considered for large or painful lesions. Careful collaborations with multiple specialties through tumor boards or other mechanisms help to optimize complex management decisions in these patients with advanced thyroid cancer. Multimodality monitoring focused on the organ of interest such as pulmonary [computed tomography (CT)], bone (magnetic resonance imaging, CT, bone scan), and brain (CT, magnetic resonance imaging) metastases as well as general metastatic surveillance (bone scan, (18)F-fluorodeoxyglucose-positron emission tomography) aid decision making about careful monitoring vs. directed or systemic therapy. (18)F-fluorodeoxyglucose-positron emission tomography imaging has an additional role in patient prognosis and guiding directed therapy for fluorodeoxyglucose-avid lesions. Patients with asymptomatic, stable, radioiodine-resistant metastases may be carefully monitored for disease progression. Patients with symptomatic disease should receive directed therapy with the goal of symptom relief. Patients with progressive metastatic disease should be considered for clinical trials or targeted systemic therapy (sorafenib or sunitinib), although these agents are not Food and Drug Administration (FDA) approved for patients with thyroid cancer. The goals of therapy for patients with extracervical metastases should be to improve survival, relieve symptoms, and decrease the morbidity of disease progression and limit the morbidity associated with therapy.