Extrathyroidal extension and cervical node infiltration are associated with recurrences and shorter recurrence-free survival in differentiated thyroid cancer: a cohort study

Background

Differentiated thyroid cancer has excellent overall survival. However, around 20% of patients experience recurrent diseases after a certain time of follow-up. Therefore, identification of risk factors for recurrence is necessary to adjust treatment and surveillance planning.

Methods

A retrospective study was conducted of 312 patients with differentiated thyroid cancer who received surgery with and without adjuvant treatment. Clinical and pathological risk factors were analyzed for recurrences.

Results

After median follow-up of 57 months, 109 of 312 patients (34.9%) developed recurrences. Extrathyroidal extension and positive cervical nodes were significantly associated with recurrences (OR = 2.449, 95%CI:1.260–4.760, P = 0.008 and OR = 3.511, 95%CI:1.860–6.626, P < 0.001; respectively). Lympho-vascular invasion (LVI) and tumor multifocality were also associated with increased risk of recurrence (OR = 2.577, 95%CI:1.380–4.812, P = 0.003 and OR = 1.602, 95%CI:1.001–2.495, P = 0.050; respectively). Using multivariable regression, only older age and tumor infiltration to the lymph nodes were significantly associated with recurrences (OR = 2.227, 95%CI:1.037–4.782, P = 0.040 and OR = 2.966, 95%CI:1.470–5.986, P = 0.002; respectively). In addition, T4, cervical lymph node infiltration, older age, and LVI were associated with shorter recurrence-free survival.

Conclusion

Recurrence rates in our study population are relatively high. Extrathyroidal extension, positive neck lymph node, and older age were associated with recurrence risks of well differentiated thyroid cancers.

E-cadherin on epithelial-mesenchymal transition in thyroid cancer

Thyroid carcinoma is a common malignant tumor of endocrine system and head and neck. Recurrence, metastasis and high malignant expression after routine treatment are serious clinical problems, so it is of great significance to explore its mechanism and find action targets. Epithelial-mesenchymal transition (EMT) is associated with tumor malignancy and invasion. One key change in tumour EMT is low expression of E-cadherin. Therefore, this article reviews the expression of E-cadherin in thyroid cancers (TC), discuss the potential mechanisms involved, and outline opportunities to exploit E-cadherin on regulating the occurrence of EMT as a critical factor in cancer therapeutics.

Peace of mind for patients with differentiated thyroid cancer?

Differentiated thyroid carcinomas (DTC) have an excellent prognosis, with 10-year overall survival rates over 90%. In addition, DTC patients benefit from their lifelong medical surveillance. The aim of the study was to compare the patients’ overall survival with that of a matched general population. Patients and methods: We have analyzed 1497 consecutive patients with DTC, who underwent radioiodine therapy in Münster, Germany, according to international standards. We classified our patients according to the current 7th edition of the UICC (Union Internationale Contre le Cancer) classification and we compared the overall survival of the patients with the expected survival based on age and sex of the general population as provided by the Federal Statistical Office, Germany. Results: There were no significant differences in overall survival rates between DTC patients of the cohort in stages I to IVa compared to the expected survival based on age and sex of the general population. However, patients in stage IVc showed a significantly worse overall survival rate using the log-rank test (p < 0.0001). Conclusion: Patients with DTC showed excellent overall survival rates in stages I, II, III and IVa. All patients, except for those in stage IVc (M1 ≥ 45 years), had overall survival rates similar to the general population.

A novel nonparametric measure of explained variation for survival data with an easy graphical interpretation

INTRODUCTION

For survival data the coefficient of determination cannot be used to describe how good a model fits to the data. Therefore, several measures of explained variation for survival data have been proposed in recent years.

METHODS

We analyse an existing measure of explained variation with regard to minimisation aspects and demonstrate that these are not fulfilled for the measure.

RESULTS

In analogy to the least squares method from linear regression analysis we develop a novel measure for categorical covariates which is based only on the Kaplan-Meier estimator. Hence, the novel measure is a completely nonparametric measure with an easy graphical interpretation. For the novel measure different weighting possibilities are available and a statistical test of significance can be performed. Eventually, we apply the novel measure and further measures of explained variation to a dataset comprising persons with a histopathological papillary thyroid carcinoma.

CONCLUSION

We propose a novel measure of explained variation with a comprehensible derivation as well as a graphical interpretation, which may be used in further analyses with survival data.

Papillary thyroid carcinoma in Denmark, 1996-2008: outcome and evaluation of established prognostic scoring systems in a prospective national cohort

BACKGROUND

Regional as well as national series show an increasing incidence of thyroid cancer largely small size papillary thyroid carcinoma (PTC). Prognostic scoring systems have been developed, but these do not take into account the rapidly changing case mix, and adjustments may be required. The purposes of this study were to evaluate treatment outcomes and to analyze the value of older prognostic scoring systems tested on a relatively new, unselected national cohort of PTC patients.

METHODS

This was a national prospective cohort study conducted in Denmark, which has a population of 5.5 million.

RESULTS

A total of 1350 patients were diagnosed with PTC during 1996-2008, and the median follow-up time was 7.9 years. The 10-year recurrence-free survival rate was 90.2%, and the 10-year crude and cause-specific survival (CSS) rates were 83.7% and 93.8% respectively. By multivariate Cox regression, it was possible to confirm age, metastases (distant and nodal), extrathyroidal extension, and tumor size as predictors of mortality, whereas only nodal metastases, extrathyroidal extension, and tumor size were predictors of recurrence. In analyses of older prognostic scoring systems, a significant correlation between the risk group ranks was found for survival as well as recurrence. The c-index for CSS was highest for MACIS (0.92) and lowest for AMES (0.80). In the TNM, MACIS, and EORTC systems, most patients were classified as stage 1, and for these patients, the 10-year CSS rate was approximately 99.5%, confirming the generally excellent survival.

CONCLUSION

This national study provides further evidence that a favorable prognosis is to be expected for patients diagnosed with PTC. Also, it was possible to confirm age, metastases, extrathyroidal extension, and tumor size as predictors of mortality, whereas only nodal metastases, extrathyroidal extension, and tumor size were predictors of recurrence. All the scoring systems evaluated were able to produce a highly significant risk group stratification, showing that in spite of the changes in the case mix of PTC, these systems are still applicable, and in fact contain valuable prognostic information useable for treatment planning.

Tissue transglutaminase: an emerging target for therapy and imaging

Tissue transglutaminase (transglutaminase 2) is a multifunctional enzyme with many interesting properties resulting in versatile roles in both physiology and pathophysiology. Herein, the particular involvement of the enzyme in human diseases will be outlined with special emphasis on its role in cancer and in tissue interactions with biomaterials. Despite recent progress in unraveling the different cellular functions of transglutaminase 2, several questions remain. Transglutaminase 2 features in both confirmed and some still ambiguous roles within pathological conditions, raising interest in developing inhibitors and imaging probes which target this enzyme. One important prerequisite for identifying and characterizing such molecular tools are reliable assay methods to measure the enzymatic activity. This digest Letter will provide clarification about the various assay methods described to date, accompanied by a discussion of recent progress in the development of inhibitors and imaging probes targeting transglutaminase 2.

No significant difference in the prognostic value of the 5th and 7th editions of AJCC staging for differentiated thyroid cancer

OBJECTIVE

The seventh edition of the American Joint Committee on Cancer (AJCC) has more detailed staging categories for differentiated thyroid cancer (DTC) than the fifth edition. The aim was to compare potential alterations in the disease-specific (DSS), event-free (EFS) and overall survival (OS), after reclassification from the fifth to the seventh edition.

METHODS

Data of 2460 patients with DTC referred to our centre were reclassified from the fifth to the seventh edition of AJCC. DSS, EFS and OS were calculated using the Kaplan-Meier method and compared by the log-rank test. The relative abilities of each edition to predict survival were calculated by the proportion of variance explained (PVE).

RESULTS

After reclassification to the seventh edition, there was an increase in stage I and IV patients from 58·1% to 65·0% and from 6·2% to 10·1%, respectively, and a corresponding decrease in stage II and III patients from 22·4% to 12·5% and 13·3% to 12·4%, respectively. As to DSS, the seventh edition had only a marginally higher PVE value than the fifth edition. With respect to EFS, the predictability of the seventh edition was even inferior to that of the fifth edition. Similarly, with regard to OS, the PVE value was slightly better for the older edition. Furthermore, a comparison only for those patients affected by the reclassification revealed no differences for DSS, EFS or OS between classifications.

CONCLUSION

When comparing the stages of the seventh with the fifth edition of the AJCC for DTC, there was no significant difference in predicting DSS, EFS and OS.