Resultados del tratamiento del cáncer de tiroides / Thyroid cancer treatment results

El cáncer de tiroides es la neoplasia maligna más frecuente del sistema endocrino, siendo el más frecuente el cáncer bien diferenciado (papilar y folicular). El propósito de este trabajo es recoger nuestra experiencia clínica en el manejo y resultados del cáncer diferenciado de tiroides. Material y métodos: Estudio retrospectivo de 50 casos de pacientes con tumores malignos tiroideos, intervenidos de tiroidectomía total por nuestro servicio durante el periodo de 2015 a 2018. Se han recogido variables clínico-epidemiológicas que han sido procesadas con el programa SPSS versión 25. Se realiza estudio descriptivo y de asociación entre las diferentes variables según el tipo anatomo-patológico de tumor. Se analiza la probabilidad de recidiva del cáncer de tiroides y se utiliza el modelo de Cox para ajustar los efectos sobre la recidiva de diferentes variables en un modelo predictivo. Resultados: El 84% eran carcinoma papilar y 16% eran carcinoma folicular. Al finalizar el periodo de seguimiento (72 meses), el 14% presentaba recidiva, y habían fallecido el 8%. El carcinoma folicular fue el que mostró menor supervivencia. El tiempo medio sin recaída, fue de 129 meses. Las variables que influían en la supervivencia fueron: existencia de complicaciones en el postoperatorio, valor de tiroglobulina y antitiroglobulina y TIRADS. Conclusión: Coincidimos con el resto de autores en los aspectos epidemiológicos y clínicos. El carcinoma papilar es el más frecuente y tiene mejor pronóstico. Entre los factores que influyen en la supervivencia destacan el sexo y el tipo anatomo-patológico. Otros factores a considerar son: la existencia de complicaciones en el postoperatorio, la categoría TIRADS previa al tratamiento, y los valores de tiroglobulina y antitiroglobulina en los controles postoperatorios. (AU)

Thyroid cancer is the most frequent malignant neoplasm of the endocrine system, with well-differentiated cancer (papillary and follicular) being the most frequent. The purpose of this work is to collect our clinical experience in the management and results of well-differentiated thyroid cancer. Material and methods: Retrospective study of 50 cases of patients with malignant thyroid tumors, who underwent total thyroidectomy by our service during the period from 2015 to 2018. Clinical-epidemiological variables were collected and processed using the SPSS version 25 program. We have conducted a descriptive and association study between different variables according to anatomo-pathological tumor type. The probability of recurrence of thyroid cancer is analyzed and Cox model is used to adjust the effects on recurrence of different variables in a predictive model. Results: 84% were papillary carcinoma, and 16% were follicular carcinoma. At the end of the follow-up period (72 months), 14% had recurrence, and 8% had died. Follicular carcinoma showed the lowest survival. The mean time without relapse was 129 months. The variables that influenced survival were existence of postoperative complications, thyroglobulin and antithyroglobulin value, and TIRADS. Conclusion: We agree with the rest of the authors in the epidemiological and clinical aspects. Papillary carcinoma is the most frequent and has a better prognosis. Among the factors that influence survival, sex and anatomo-pathological type stand out. Other factors to consider are the existence of complications in the postoperative period, TIRADS category prior to treatment, and thyroglobulin and antithyroglobulin values in postoperative controls. (AU)

Long-term follow-up of differentiated thyroid carcinoma in children and adolescents.

Objectives The aims were to analyze the clinical features, response to treatment, prognostic factors and long-term follow-up of children and adolescents with differentiated thyroid carcinoma (DTC). Methods Eighty patients with DTC were studied retrospectively. All underwent total or near-total thyroidectomy, and in 75 cases, ablative iodine therapy was recommended. Patients were assessed periodically by tests for serum thyroglobulin levels and whole-body iodine scans. Age, gender, initial clinical presentation, histology, tumor stage, postoperative complications, radioiodine treatment protocol, treatment response, thyroglobulin (Tg), recurrence and long-term disease progression were evaluated. Results Seventy patients completed >2 years of follow-up (23 males, 47 females; median age: 14 years; range: 3-18 years). Sixty-two patients showed papillary DTC and eight, follicular DTC. Sixty-five percent presented nodal metastasis and 16%, pulmonary metastasis at diagnosis. Six months after first radioiodine treatment, 36.2% of patients were free of disease. Seven recurrences were documented. At the end of follow-up, overall survival was 100%, and 87.2% of patients were in complete remission. Nine patients had persistent disease. We found a significant association between stage 4 and persistent disease. Hundred percent of patients with negative Tg values at 6 months posttreatment were documented free of disease at the end of the follow-up. The analysis of disease-free survival based on radioiodine treatment protocols used showed no statistically significant differences. Conclusions DTC in children and adolescents is frequently associated with presence of advanced disease at diagnosis. Despite this, complete remission was documented after treatment in most cases, with a good prognosis in the long-term follow-up. Negative posttreatment thyroglobulin and stage 4 at diagnosis were significant prognostic variables.

Outcome of classical (CVPTC) and follicular (FVPTC) variants of papillary thyroid cancer: 15 years of follow-up.

PURPOSE: To compare the epidemiological, clinical, and pathological features of follicular (FVPTC) and classical (CVPTC) variants of papillary thyroid cancer and to correlate their outcomes according to different features. METHODS: Retrospective analysis of FVPTC and CVPTC patients selected at the moment of surgical treatment from 1999 to 2004, with a median follow-up of 15 years. RESULTS: Several significant differences were found between FVPTC and CVPTC such as the mean age at diagnosis, the presence of tumor capsule, the presence of thyroid capsule invasion, the presence of perithyroid soft tissue invasion, the lymph node metastases, the multifocality and bilaterality. At the end of follow-up only 9% (77/879) patients were not cured. However, a statistically significant lower percentage of persistent disease was found in the FVPTC than in the CVPTC group (3% vs. 14.5%, respectively, p < 0.0001). In multivariate analysis, the absence of the tumor capsule (OR = 6.75) or its invasion (OR = 7.89), the tumor size ≥4 cm (OR = 4.29), the variant CVPTC (OR = 3.35), and the presence of lymph node metastases (OR = 3.16) were all independent risk factors for the persistence of the disease. CONCLUSIONS: Despite an overall excellent prognosis of both variants, a higher percentage of CVPTC than FVPTC patients had a persistent disease. The absence of tumor capsule or its invasion, the tumor size ≥4 cm and the presence of lymph node metastases are other prognostic factors for the persistence of the disease. In contrast, the presence of an intact tumor capsule is the only good prognostic factor for their outcome.

Systematic Review and Meta-analysis of the Impact of Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP) on Cytological Diagnosis and Thyroid Cancer Prevalence.

A re-named diagnosis of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) likely impacts the prevalence of thyroid cancer and risk of malignancy in populations based on the established Bethesda System of Reporting Thyroid Cytopathology (TBSRTC). This study was done to investigate the prevalence and cytological distribution of NIFTP. PRISMA guided systematic review was done from a database search of Pubmed, EMBASE, and Medline using the search terms "non-invasive follicular thyroid neoplasm with papillary-like nuclear features", "non-invasive follicular variant of papillary carcinoma", "niftp", and "Bethesda" until November 2018. Original articles with surgically proven diagnoses of NIFTP using strict NIFTP criteria were included. Twenty-nine studies with 1563 cases of NIFTP were included. The pooled prevalence of NIFTP in cases which would be classified previously as the follicular variant of papillary thyroid cancer (FVPTC) and papillary thyroid cancer (PTC) were 43.5% (95% CI 33.5-54.0%) and 4.4% (95% CI 2.0-9.0%) respectively. The pooled TBSRTC distribution of cases diagnosed as NIFTP was: from the non-diagnostic category 3.6% (95% CI 2.4-5.3%), benign 10.0% (95% CI 7.2-13.6%), AUS/FLUS 34.2% (95% CI 28.2-40.8%), FN/SFN 22.7% (95% CI 17.2-29.4%), suspicious for malignancy 22.4% (95% CI 17.7-27.9%), and malignant 7.5% (95% CI 4.2-12.9%). While a significant reduction in FVPTC prevalence is anticipated, a modest reduction of PTC prevalence is also expected with adoption of the NIFTP terminology that would be distributed mainly among lesions classified as indeterminate thyroid nodules. Further studies are needed to identify unique clinical characteristics of these lesions preoperatively.

Incidence of noninvasive follicular thyroid neoplasm with papillary-like nuclear features and change in risk of malignancy for "The Bethesda System for Reporting Thyroid Cytology".

INTRODUCTION: The second edition of The Bethesda System for Reporting Thyroid Cytopathology has incorporated the recent change in nomenclature, noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), with an anticipated change in the risk of malignancy (ROM). We examined our institutional experience in the incidence of NIFTP and the change in the ROM in The Bethesda System for Reporting Thyroid Cytopathology. MATERIALS AND METHODS: A computerized search was performed from January 2013 to August 2017 for all thyroid fine needle aspirations (FNAs), the corresponding surgical resection specimens, and clinical follow-up data. All thyroid specimens reported as follicular variant of papillary thyroid carcinoma were reviewed and reclassified, and all NIFTP diagnoses from April 2016 to August 2017 were identified. The ROM for each category was calculated before and after the change and analyzed for significance. RESULTS: A total of 4500 thyroid FNA cases were collected. Of these, 479 cases had surgical resection specimens available and 36 cases had been diagnosed as NIFTP. Of these, 22 had been previously diagnosed as FVPT. Of 27 cases of NIFTP, 14 and 13 were atypia of undetermined significance/follicular lesion of undetermined significance and follicular neoplasm/suspicious for follicular neoplasm, respectively. A reduction in the ROM was observed in these 2 categories (P = 0.03 and P = 0.04, respectively). CONCLUSIONS: In our institution, NIFTP has accounted for 13% of all malignant thyroid neoplasms since the change in nomenclature. Although the ROM was decreased in the affected categories, with absolute statistically significant decreases in ROM of 15% and 16.2% for category III and IV, respectively, the overall ROM change was marginal.

Clinical Safety of Renaming Encapsulated Follicular Variant of Papillary Thyroid Carcinoma: Is NIFTP Truly Benign?

BACKGROUND: Renaming encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC) to noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was recently suggested to prevent the overtreatment, cost and stigma associated with this low-risk entity. The purpose of this study is to document the incidence and further assess the clinical outcomes of reclassifying EFVPTC to NIFTP. METHODS: We searched synoptic pathologic reports from a high-volume academic endocrine surgery hospital from 2004 to 2013. The standard of surgical pathology practice was based on complete submission of malignant thyroid nodules along with the nontumorous thyroid parenchyma. Rigid morphological criteria were used for the diagnosis of noninvasive EFVPTC, currently known as NIFTP. A retrospective chart review was conducted looking for evidence of malignant behavior. RESULTS: One hundred and two patients met the strict inclusion criteria of NIFTP. The incidence of NIFTP in our cohort was 2.1% of papillary thyroid cancer cases during the studied time period. Mean follow-up was 5.7 years (range 0-11). Five patients were identified with nodal metastasis and one patient with distant metastasis. Overall, six patients showed evidence of malignant behavior representing 6% of patients with NIFTP. CONCLUSION: Our study demonstrates that the incidence of NIFTP is significantly lower than previously thought. Furthermore, evidence of malignant behavior was seen in a significant number of NIFTP patients. Although the authors fully support the de-escalation of aggressive treatment for low-risk thyroid cancers, NIFTP behaves as a low-risk thyroid cancer rather than a benign entity and ongoing surveillance is warranted.

Prevalence of Contralateral Tumors in Patients with Follicular Variant of Papillary Thyroid Cancer.

BACKGROUND: Thyroid lobectomy alone is being performed increasingly for patients with encapsulated follicular variant of papillary thyroid carcinoma (fvPTC). However, the prevalence of contralateral disease in these patients is unknown. We investigated the presence of synchronous disease in fvPTC to improve decision making about the extent of surgical resection and need for surveillance. STUDY DESIGN: We performed a retrospective review of patients who underwent thyroid surgery from October 2009 to February 2013 with a diagnosis of fvPTC as their primary lesion. We collected information on patient demographics, nodule size, multifocality, fine-needle aspiration results, lymphovascular invasion, extrathyroidal extension, and lymph node metastasis. Tumors were divided into noninvasive and invasive/infiltrative fvPTC categories. Characteristics of solitary and bilateral fvPTC were compared. RESULTS: We identified 124 patients with final pathology demonstrating fvPTC. The most common fine-needle aspiration diagnosis was "suspicious for malignancy" (n = 53). Sixty-five contralateral tumors were identified in 44 of 124 patients (35.5%) and included fvPTC (n = 40), classical PTC (n = 22), tall cell PTC (n = 2), and follicular carcinoma (n = 1). Fifty contralateral tumors were 1 to 5 mm, 10 measured 6 to 9 mm, and 5 were ≥10 mm. Contralateral disease correlated significantly with lymphovascular invasion (p = 0.037) and larger primary lesions (p = 0.020). There was no significant difference noted in extrathyroidal extension or lymph node metastasis. Both noninvasive and invasive/infiltrative fvPTC demonstrated similar rates of contralateral disease. CONCLUSIONS: Bilateral disease is common in fvPTC, primarily in the form of papillary microcarcinomas. Future monitoring of the contralateral lobe should be discussed with fvPTC patients who do not undergo completion thyroidectomy.

Morphological difference in adult thyroid papillary carcinoma between Japan and Ukraine.

Geographic differences have been reported to affect the morphological and molecular features of papillary thyroid carcinomas (PTCs). The area around Chernobyl is well-known to be iodine-deficient in contrast to Japan, an iodine-rich country. We reviewed histological differences in adult PTC between Ukraine and Japan. In total, 112 PTCs from age- and sex-matched adults (Ukraine 56, Japan 56) were evaluated histologically for several factors including tumor size, capsulation, tumor components (papillary, follicular, solid, trabecular), lymph node metastasis, extrathyroid invasion, lymphocytic infiltration, oxyphilic metaplasia, and MIB-1 index. We demonstrated that tumors were smaller (1.56 vs. 2.13 cm, p<0.05) and more solid and that lymph node metastasis was less frequent (14.3% vs. 48.2%, p<0.001) in Ukrainian cases. PTC subtype distribution was significantly different between the two groups. Solid variant (8.9% vs. 1.8%) and mixed subtypes with solid components were more frequent in Ukrainian patients. In contrast, classical papillary carcinomas were more frequent in Japanese cases (10.7% vs. 50.0%, p<0.001). Marked oxyphilic metaplasia was more common in Ukrainian cases (33.9 % vs. 8.9 %, p<0.001). MIB-1 index was significantly higher in Ukrainian cases (2.9% vs. 1.8%, p<0.001). However, the frequencies of tumor capsule formation and background lymphoid follicle formation around the tumor were similar between groups. Morphological differences in adult PTCs were similar to those in pediatric PTCs as reported previously, suggesting that morphogenesis of PTC is influenced by environmental factors, especially dietary iodine, as well as genetic factors.

The large majority of 1520 patients with indeterminate thyroid nodule at cytology have a favorable outcome, and a clinical risk score has a high negative predictive value for a more cumbersome cancer disease.

CONTEXT: Clinical management of patients with thyroid nodules indeterminate at fine-needle aspiration (FNA) cytology is still unsettled. OBJECTIVE: Our objective was to establish the clinical outcome of patients with thyroid nodules indeterminate at cytology and to identify the features associated with malignancy. DESIGN AND PATIENTS: This was a retrospective evaluation of 1520 consecutive patients with indeterminate cytology among 100 065 patients who underwent FNA between January 2000 and December 2010. RESULTS: Of 1520 patients, 371 (24.4 %) had thyroid cancer at histology, the follicular variant of papillary cancer being the most frequent histotype, and 342 patients with cancer were free of disease after thyroidectomy and (131)I remnant ablation, whereas 29 needed further treatment because of persistent disease. Among them, only 12 had persistence of disease at the end of follow-up. Atypias at cytology (P = .001), blurred nodule margins (P = .005), and spot microcalcifications (P = .003) at thyroid ultrasound (US) were significantly associated with malignancy. A clinical score including cytology and US characteristics was calculated; the lowest value showed a high negative predictive value (83.9%) for the presence of malignancy and even higher (99.5%) for the presence of a more cumbersome cancer disease, and only 4 of the 29 patients who needed further treatment were included in the group with the lowest risk score. CONCLUSIONS: Patients with Thy 3 cytology and histology of thyroid cancer had an overall good prognosis. A clinical risk score including the results of cytology and US features is helpful in the management of patients with indeterminate thyroid nodules.

No adverse affect in clinical outcome using low preablation diagnostic (131)i activity in differentiated thyroid cancer: refuting thyroid-stunning effect.

CONTEXT: Published studies of thyroid stunning due to preablation (131)I scanning in the treatment of differentiated thyroid cancer after thyroidectomy had shown inconsistent clinical impact. OBJECTIVE: The objective of the study was to evaluate the clinical outcome in patients who were given a low diagnostic (131)I activity (1.1 mCi or 40 MBq) 6 days prior to radioiodine ablation (RAI). DESIGN/SETTING: Two cohorts of patients were treated in a cancer referral center in 2004-2011. The eligibility criteria were as follows: 1) diagnosis of differentiated thyroid cancer; 2) total or near total thyroidectomy; 3) no distant metastasis; and 4) receiving 82.4 mCi or greater (3050 MBq) therapeutic (131)I activity. PATIENTS/INTERVENTIONS: Three hundred five consecutive patients treated in 2004-2008 (group A) had a diagnostic activity 1.1 mCi of (131)I prior to RAI. The second cohort treated in 2009-2011 (group B) consisted of 237 patients who did not undergo diagnostic (131)I scanning prior to RAI. MAIN OUTCOME MEASURES: The tumor recurrence rate at 3 years and quantitative assessment using diagnostic whole-body radioiodine scans and TSH-stimulated thyroglobulin levels at 3-12 months after RAI were measured. RESULTS: The 3-year recurrence-free survival rates were 96.4% in both groups, with 4.3% in group A and 3.4% in group B having tumor recurrence (P = .91). The ablation success rates measured by diagnostic whole-body radioiodine scans were 97.6% and 100% and by stimulated thyroglobulin were 85.3% and 85.8% in group A and B, respectively (P = .62). CONCLUSIONS: The use of low diagnostic (131)I activity (1.1 mCi) given 6 days prior to RAI was safe and convenient without adversely affecting the long-term clinical outcome.

Increased risk of differentiated thyroid carcinoma with combined effects of homologous recombination repair gene polymorphisms in an Iranian population.

Homologous recombination (HR) repair has a crucial role to play in the prevention of chromosomal instability, and it is clear that defects in some HR repair genes are associated with many cancers. To evaluate the potential effect of some HR repair gene polymorphisms with differentiated thyroid carcinoma (DTC), we assessed Rad51 (135G>C), Rad52 (2259C>T), XRCC2 (R188H) and XRCC3 (T241M) polymorphisms in Iranian DTC patients and cancer-free controls. In addition, haplotype analysis and gene combination assessment were carried out. Genotyping of Rad51 (135G>C), Rad52 (2259C>T) and XRCC3 (T241M) polymorphisms was determined by PCR-RFLP and PCR-HRM analysis was carried out to evaluate XRCC2 (R188H) . Separately, Rad51, Rad52 and XRCC2 polymorphisms were not shown to be more significant in patients when compared to controls in crude, sex-adjusted and age-adjusted form. However, results indicated a significant difference in XRCC3 genotypes for patients when compared to controls (p value: 0.035). The GCTG haplotype demonstrated a significant difference (p value: 0.047). When compared to the wild type, the combined variant form of Rad52/XRCC2/XRCC3 revealed an elevated risk of DTC (p value: 0.007). It is recommended that Rad52 2259C>T, XRCC2 R188H and XRCC3 T241M polymorphisms should be simultaneously considered as contributing to a polygenic risk of differentiated thyroid carcinoma.

Evaluation of thyroid diseases and differentiated thyroid cancer in acromegalic patients.

Thyroid diseases are frequently seen in patients with acromegaly. The aim of this study is to evaluate thyroid diseases and thyroid cancer in acromegalic patients followed in a single institution. The data of 92 acromegalic (43 male, 49 female) patients followed over 12 years were retrieved retrospectively from the hospital recordings. All available data for gender, age, body weight and height, duration of acromegaly, age at diagnosis of acromegaly, treatment methods for acromegaly and history of thyroid disease, serum GH, IGF-1, thyroid function tests, thyroid ultrasonography (US), thyroid scintigraphy and thyroid fine needle aspiration biopsy (FNAB) results were recorded for the patients. The mean age of the patients was 43.9 ± 10.8 years and the mean disease duration was 12 ± 6.9 years. Thyroid US was performed in 64 patients who had nodular or diffuse goiter on palpation during the post-treatment follow-up and nodules were found in 44 (47.8 %) patients. Final diagnosis in 64 patients with thyroid US results and thyroid function tests including 26 patients with FNAB were as follows: 31 (48.4 %) benign multinodular goiter (MNG), 6 (9.4 %) simple nodular goiter, 1 (1.6 %) toxic MNG, 1 (1.6 %) Hurthle cell adenoma, and 5 (7.8 %) differentiated thyroid cancer. In addition, 9 (14.1 %) patients had diffuse goiter. One of the patients with diffuse goiter had amiodarone induced thyrotoxicosis. Eleven (17.1 %) patients had normal thyroid US and no other thyroid disease. Patients with nodules had longer disease duration than patients without nodules (14.2 ± 6.6 vs. 9.4 ± 3.4 years, p = 0.043). Thyroid volume was positively correlated with post-treatment GH and post-treatment IGF-1 levels (r = 0.309, p = 0.041 and r = 0.423, p = 0.004), respectively. We found that 7.8 % of our acromegalic patients with thyroid US results were diagnosed with thyroid cancer. Therefore, acromegalic patients must be considered as a high risk group for the development of thyroid cancer and must be closely followed for thyroid nodules and tumors.

Impact of early vs late postoperative radioiodine remnant ablation on final outcome in patients with low-risk well-differentiated thyroid cancer.

OBJECTIVE: Postoperative radioiodine remnant ablation (RRA) represents an adjunctive therapeutic modality in patients with differentiated thyroid cancer (DTC). The impact of late vs early RRA on the outcome of DTC is currently unclear. The aim of the study was to evaluate the outcome of patients with DTC according to RRA timing. DESIGN RETROSPECTIVE STUDY PATIENTS: A total of 107 TNM stage 1 DTC patients were divided into two groups. In group A (n = 50), RRA was administered in less than 4·7 months median 3·0 (range 0·8-4·7), while in group B (n = 57) in more than 4·7 months median 6 (4·8-30·3) after thyroidectomy. Remission was achieved when stimulated serum Tg levels were undetectable, in the absence of local recurrence or cervical lymph node metastases on the neck ultrasound. RESULTS: All patients underwent near-total thyroidectomy. The mean age at diagnosis was 49·3 years (range: 18-79 years). There were no statistically significant differences in the histological subtype, the TNM stage, the dose of radioiodine and the time of follow-up, between the two groups. After the RRA treatment, 44 group A patients (88%) were in remission and 6 (12%) in persistence; while in group B, 52 (91·2%) were in remission, 1 (1·8%) in persistence and 4 (7%) in recurrence. At their latest follow-up median 87·3 (23·3-251·6 months), all patients were in remission, either as a result of further iodine radioiodine therapy (in 11 patients) or watchful monitoring. CONCLUSIONS: The timing of RRA seems to have no effect on the long-term outcome of the disease. Therefore, urgency for radioiodine ablation in patients with low-risk thyroid cancer is not recommended.

[Comparative rate of regional metastasis of high differentiated carcinoma of the thyroid gland].

The rate of metastasis of high differentiated carcinoma of the thyroid glands to the neck lymph nodes was studied in people of Kemerovo Region. The metastatic lesions of pretracheal lymph nodes (VI group) were detected in 49.5% patients with papillary carcinoma and 21.0% of patients with follicular cancer. Metastases in jungular lymph nodes were revealed in 37.3% patients with papillary carcinoma. It was noted that an extension of metastatic lesions of regional lymph nodes was observed in the case of primary tumour foci spread beyond borders of the capsula glandularis in patients with papillary carcinoma. There wasn't such a relation in a case of follicular cancer. Metastases in regional lymph nodes were detected more often (67.6%) in the case of papillary carcinoma in uncontaminated zone of the thyroid gland compared with other thyroid pathology (31.7%).

Life expectancy is reduced in differentiated thyroid cancer patients ≥ 45 years old with extensive local tumor invasion, lateral lymph node, or distant metastases at diagnosis and normal in all other DTC patients.

OBJECTIVE: Differentiated thyroid carcinoma (DTC) generally has a good prognosis. As yet, however, it is unclear whether life expectancy is reduced in these patients and, if so, to what extent. The aim of this study was to determine how the all-cause mortality rate in DTC patients compares to that of the general population. DESIGN: A prospective database study was conducted. PATIENTS: The study included 2011 DTC patients treated in our hospital from 1980-2011. All patients received total thyroidectomy with subsequent (131)I ablation, except for those with an isolated papillary microcarcinoma. Survival data for the general German population were obtained from the German Federal Statistics Agency and matched to our DTC population for age and sex. RESULTS: Patients who were at least 45 yr old at diagnosis and had extensive perithyroidal invasion (UICC/AJCC TNM system, 7th edition, stages IVa and IVb), lateral cervical lymph node metastases (TNM stage IVa), or distant metastases (TNM stage IVc) showed a clearly reduced life expectancy [relative cumulative survival rate (observed:expected) for stage IVc after 20 yr, 0.295; 95% confidence interval, 0.033-0.556]. In patients over 60 yr of age at diagnosis, the loss of life expectancy was (much) greater than for those aged 45-59 yr in all groups. Life expectancy was not reduced in patients with TNM stages I, II, or III (86% of patients). CONCLUSION: Life expectancy is not significantly reduced in 86% of DTC patients; only patients at least 45 yr old with extensive local invasion, lateral lymph node metastases, and/or distant metastases (TNM stages IVa, IVb, and IVc) at diagnosis showed a clearly lower life expectancy.

New and old knowledge on differentiated thyroid cancer epidemiology and risk factors.

Differentiated thyroid cancer (DTC) represents 1-2% of all human malignancies. The annual incidence varies among countries and it is estimated that 1.2-2.6 men and 2.0-3.8 women/100,000 individuals are affected worldwide. This incidence has been increasing in the last decades, likely due to an "over-diagnosis" of small cancers that would have remained occult and that have been likely revealed because of an increased diagnostic scrutiny rather than a real increase of incidence. The annual mortality rate for DTC is 0.5/100,000 both in men and women. DTC is 2-4 times more frequent in females than in males. The mean age at diagnosis is 40-45 yr for papillary tumors (PTC) and 50-55 yr for follicular tumors (FTC). They are very rare in children. Ninety percent of DTC are represented by PTC hystotype, mainly follicular and classical variants. In the last years it has been observed an important change in the oncogenic pattern of PTC with a significant reduction of RET/PTC rearrangements and an increase of BRAFV600E mutation suggesting a change in pathogenic events. The unique well-demonstrated risk factor of DTC is the exposure to external radiation which is also correlated with the presence of RET/PTC rearrangements. Recently, other environmental factors (i.e. living in a volcanic area or in a iodine- either deficient or rich area) or some eating habits leading to obesity have been considered as potential DTC risk factors. However, at present, the favorite hypothesis is that a complex interaction between genetic and environmental factors is required to develop DTC.

Increasing diagnosis of thyroid papillary carcinoma follicular variant in south-east Anatolian region: comparison of characteristics of classical papillary and follicular variant thyroid cancers.

We aimed to compare ratios of thyroid cancers diagnosed in our regional reference hospital Pathology Center in Sanliurfa city located in southeast Anatolia, and evaluate the characteristics related with follicular variant papillary thyroid carcinoma (FVPTC). We re-evaluated the specimens of last 5 years thyroidectomies by same five pathologists, by same criteria and immunohistochemical evaluation. Chi-square test was used to compare characteristics of classical pure papillary thyroid carcinomas and FVPTC groups. Stepwise multiple regression analysis was used to evaluate the factors related with presence of FVPTC. Among 400 thyroidectomies, there were 105 papillary thyroid carcinoma, 42 of them with pure PTC, and 56 with FVPC, also seven with other variants. There was increase in ratios of FVPTC/PTC between 2010 and 2011 (68.4 vs 76.7%, p < 0.005). Radius, vascular invasion, and extrathyroidal invasion showed statistically significant difference between pure PTC and FVPTC. In regression analysis radius (p = 0.001, OR = 2.611; 95%CI, 2.010-3.391), age (p = 0.018, OR = 0.959; 95%CI, 0.927-0.993), and multicentricity (p = 0.044, OR = 0.403; 95%CI, 0.167-0.975) were related with presence of FVPTC. Besides, further need for studies to understand whether total prevalence of FVPTC is higher in this region, and the related factors, our study showed that the ratio of FVPTC/PTC is higher in our reference hospital. Age of the patients and the radius and multicentricity of the nodules could be alarming factors for us to suspect for FVPTC.

Dietary iodine and thyroid cancer risk in French Polynesia: a case-control study.

BACKGROUND: French Polynesia has one of the world's highest thyroid cancer incidence rates. Iodine is suspected to play a role in this high incidence. The objective of this study was to assess whether low dietary iodine is related to a higher risk of thyroid cancer in the French Polynesian population. METHODS: A case-control study was performed among native residents of French Polynesia. It included 229 cases of differentiated thyroid cancer diagnosed between 1979 and 2004 (203 women, 26 men) matched with 371 population controls (324 women, 47 men) on the date of birth. The current study is focused on dietary iodine intake and fish consumption (food rich in iodine) and analyzed by conditional logistic regression. RESULTS: Daily dietary iodine intake was insufficient (<150 µg/day) in 60% of both cases and controls. A decreased risk of thyroid cancer was observed with a higher consumption of fish (p(trend)=0.008) and shellfish (p(trend)=0.002), and also with a higher dietary iodine intake (p(trend)=0.03). There was no significant interaction between the effects of the thyroid radiation dose and the dietary iodine intake (p=0.2). CONCLUSION: French Polynesia is a mild iodine deficiency area in which a higher consumption of food from the sea and a higher dietary iodine intake are significantly associated with a decreased risk of thyroid cancer. The quantification of this reduction requires specific investigation of iodine intake in traditional Polynesian food.