Differentiated thyroid cancer in children and adults: same or distinct disease? Hormones (Athens)
ABSTRACT Differentiated thyroid cancer (Dtc) is a rare disease, especially in children. Differences in the biology and clinical course of Dtc in children, when compared with adults, may be related both to pathogenesis as well as to clinical outcome of the disease. In childhood, the thyroid gland exhibits higher susceptibility to the carcinogenetic effect of ionizating radiation than in adulthood. Papillary thyroid cancer (Ptc) is more prevalent in children in comparison to adult patients. Among molecular events known to occur in papillary thyroid carcinoma, rEt/Ptc rearrangements exhibit higher prevalence in younger patients, while brAF mutations are very rare in this age group. cancer disease presents at a more advanced stage: 1) primary tumour at diagnosis is larger, especially in relation to the volume of the whole gland; 2) neck lymph node involvement is more commonly observed; 3) distant metastases are detected 3-4 times more frequently than in adults. the lungs are almost the sole distant metastatic site in children and pulmonary metastases are nearly always functional. Additionally, recurrence rates tend to be higher in children; nevertheless, cause-specific cancer mortality remains low. Up to now, thyroid cancer guidelines have been formulated on the basis of experience gained in the general population of patients. the peculiarities in childhood disease raise the question of whether it should be considered a distinct subtype, with specifically tailored therapy recommendations. A definitive answer to this question is not possible with the present state of knowledge. In the opinion of the authors, molecular analyses of childhood thyroid cancer may be crucial, as the clinical data have not satisfactorily answered this question.
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ABSTRACT: Genetic alterations involving the mitogen-activated protein kinase (MAPK) pathway are frequently demonstrated in papillary thyroid cancer (PTC). BRAF(V600E), the most frequent mutation in adult patients, is present in approximately 50% of PTC. Most clinical studies have demonstrated an association of BRAF(V600E) mutation with aggressive clinicopathological characteristics and high tumour recurrence, although the results are controversial. In this study we present the preliminary results of BRAF mutation frequence in a group of 88 Polish patients with papillary thyroid cancer (PTC) and relate it to the outcome all DTC patients operated in 2004 and 2005. BRAF (V600E) mutation was diagnosed in 38 (43%) of cases. The presence of BRAF mutation was evaluated in 88 PTC tumours. DNA was isolated from tissue parafin blocks, and the mutation V600E was evaluated by sequence analysis with an AbiPrism 377 and 3130 xl genetic analyzer (Life Technologies). Statistical analysis was carried out with the use of SPSS 12 software. The chi² and Kaplan-Meyer survival analysis were performed. From all analyzed clinico-pathological factors, only older age positively correlated with BRAF mutation frequency (p = 0.0017). Lymph node/distant metastases, multifocality, and extra-thyroid extension did not correlate with BRAF status. One cancer related death and two reccurences were observed in the BRAF+ group while one relapse was diagnosed in the BRAF- group. Although many studies document BRAF mutation as a prognostic factor in PTC our results underline that it is too early to consider it as a routine clinical predictive factor.Endokrynologia Polska 61(5):462-6. · 1.21 Impact Factor
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ABSTRACT: Children present a higher susceptibility to developing thyroid cancer after radioiodine exposure and also a higher frequency of functional metastases than adults. To assess the mRNA expression of the sodium/iodide (Na(+)/I(-)) symporter (NIS), the Pendred syndrome gene (PDS), thyroperoxidase (TPO), thyroglobulin (Tg) and TSH receptor (TSH-R) in normal thyroid tissues (NTTs) and papillary thyroid carcinomas (PTCs) among different age groups. Analysis included 59 samples: 21 NTTs and 38 PTCs, of which 21 were the classic type (CPTC) and 17 the follicular variant (FVPTC). Patients were divided into three age groups: I (n = 16) 5-21 years, II (n = 13) 22-59 years, and III (n = 10) 60-91 years. The relative mRNA expression of the five target genes was determinate by quantitative reverse transcription polymerase chain reaction (QRT-PCR). Expression of all genes was significantly higher in NTTs than in PTCs, and it was not age dependent in the NTT group. Among PTCs, the mean expression of PDS, TPO and TSH-R was significantly lower in group II than in group I. PDS, TPO and Tg expression was significantly lower in classic PTCs than in FVPTCs. The difference was related to a higher frequency of the BRAF(V600E) mutation in the former group. The finding of higher PDS, TPO and TSH-R mRNA expression in paediatric vs. adult primary tumour tissues supports the hypothesis that this might contribute to the increased functional activity of metastases in the paediatric group. The finding that mRNA expression of the target genes in NTT was not age dependent does not provide an explanation for the higher susceptibility in the paediatric group.Clinical Endocrinology 09/2008; 70(4):629-35. DOI:10.1111/j.1365-2265.2008.03376.x · 3.35 Impact Factor
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ABSTRACT: Thyroid nodules are relatively rare in children and adolescents and have a prevalence between 0.2%-1.8%. They are more often malignant in children than in adults and thus an early diagnosis is extremely important. The aim of the study was to analyze the group of pediatric patients with nodular thyroid diseases. The authors processed the documentation of 66 pediatric patients with nodular thyroid disease who have been surgically treated at the Clinic of Otorhinolaryngology and Head and Neck Surgery, JFM CU and MFH in Martin during 2003-2007. Family history was positive in 32 patients (48.5%). Twenty-three patients (35%) had hyperfunction thyroid disease. Euthyroid status was found in 43 patients (65%). Ultrasonography examination was performed in all patients. Percutaneous aspiration biopsy was performed in 38 patients (58%) and peroperative histology in 40 patients (61%). Technecium (Tc)99m-scintigraphy was performed in 4 patients (6%). CT and MRI examination of the neck and upper mediastinum was indicated in one child. All patients were surgically treated with classical approach after achieving euthyroid stage. Total thyroidectomy was performed in 24 patients, hemithyroidectomy in 41 patients and isthmectomy was done in one patient. No severe postoperative complications were present. Thyroid diseases are the second most frequent endocrinopathy in children and adolescents with girls being more frequently affected. It is multidisciplinary problem requiring cooperation of specialists in different fields of medicine. In patients with thyroid diseases not responding to conservative treatment or with clinical signs of mechanical syndrom surgery is a causal therapy (Tab. 3, Ref. 20). Full Text (Free, PDF) www.bmj.sk.Bratislavske lekarske listy 02/2009; 110(1):31-4. · 0.45 Impact Factor