Publications by authors named "Valentina Drozd"

The Chernobyl accident on 26 April 1986 led to a sharp increase in thyroid cancer (TC) incidence in the individuals exposed to radiation in childhood. The major risk factor for TC was exposure to Iodine-131 (131I). Here, we estimated the thyroid doses due to 131I intake for 2041 participants of the genome-wide association study of TC in Belarusian people exposed to radioactive fallout from the Chernobyl accident.

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The incidence of differentiated thyroid cancer (DTC) is steadily increasing globally. Epidemiologists usually explain this global upsurge as the result of new diagnostic modalities, screening and overdiagnosis as well as results of lifestyle changes including obesity and comorbidity. However, there is evidence that there is a real increase of DTC incidence worldwide in all age groups.

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This single-center, observational case-control feasibility study sought to test key elements of a protocol for an eventual long-term international observational case-control study of a larger patient cohort, to evaluate the risk of breast cancer as a second primary malignancy in females with differentiated thyroid cancer (DTC) given radioiodine therapy (RAI) during childhood or adolescence. Females developing DTC after the Chernobyl accident in Belarus and ≤19 years old at the time of thyroid surgery were enrolled: patients given RAI ( = 111) and controls of similar age not given RAI ( = 90). One case of breast cancer was newly diagnosed among the RAI patients, but none in controls.

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The thyroid gland is among the organs at the greatest risk of cancer from ionizing radiation. Epidemiological evidence from survivors of radiation therapy, atomic bombing, and the Chernobyl reactor accident, clearly shows that radiation exposure in childhood can cause thyroid cancer and benign thyroid nodules. Radiation exposure also may induce hypothyroidism and autoimmune reactions against the thyroid, but these effects are less well-documented.

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Published studies on the risk of radiation-induced second primary malignancy (SPM) after radioiodine treatment (RAI) of differentiated thyroid cancer (DTC) refer mainly to patients treated as middle-aged or older adults and are not easily generalizable to those treated at a younger age. Here we review available literature on the risk of breast cancer as an SPM after RAI of DTC with a focus on females undergoing such treatment in childhood, adolescence, or young adulthood. Additionally, we report the results of a preliminary international survey of patient registries from academic tertiary referral centers specializing in pediatric DTC.

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In recent decades, differentiated thyroid cancer (DTC) incidence has been increasing worldwide. The important contributions to this phenomenon of "overdiagnosis" driven by wider use of improved ultrasound systems are amply documented, notwithstanding the "real" carcinogenic effects of ionizing radiation, e.g.

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Background: Several functional single-nucleotide polymorphisms (SNPs) at the FOXE1 locus on chromosome 9q22.33 have been associated with the risk for papillary thyroid carcinoma (PTC). This study set out to elucidate whether their effects are independent, using genotyping results in populations of Asian and European descent.

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Recently, radiofrequency ablation (RFA) has been increasingly used for the treatment of thyroid nodules. However, immediate morphological changes associated with bipolar devices are poorly shown. To present the results of analysis of gross and microscopic alterations in human thyroid tissue induced by RFA delivered through the application of the original patented device.

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One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I) thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk.

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Long-term management of patients with differentiated thyroid cancer (DTC) commonly includes TSH-suppressive therapy with L-T4 and, in case of postsurgical hypoparathyroidism, Calcium-D3 supplementation, both of which may affect skeletal health. Experience with female patients treated for DTC at a young age and who were then receiving long-term therapy with L-T4 and Calcium-D3 medication is very limited to date. This cross-sectional study set out to investigate effects of Calcium-D3 supplementation and TSH-suppressive therapy on bone mineral density (BMD) in 124 young female patients treated for DTC at a mean age of 14 years and followed-up for an average of 10 years.

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Context: After severe reactor emergencies with release of radioactive iodine, elevated thyroid cancer risk in children and adolescents is considered the main health consequence for the population exposed.

Design: We studied thyroid cancer outcome after 11.3 years' median follow-up in a selected, very high-risk cohort, 234 Chernobyl-exposed Belarusian children and adolescents undergoing postsurgical radioiodine therapy (RIT) in Germany.

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Background: Women with a history of differentiated thyroid carcinoma who are contemplating pregnancy may wish reassurance regarding apparent remission. However, the thyroid hormone withdrawal needed to obtain serum thyroglobulin testing (Tg) results in weeks-long biochemical and clinical hypothyroidism, which could increase miscarriage and fetal death rates if pregnancy occurred during withdrawal of thyroxine or soon thereafter. Recombinant human thyrotropin (rhTSH) elevates thyrotropin exogenously, allowing uninterrupted thyroid hormone therapy and avoids hypothyroidism.

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Purpose: The objective of this project was to systematically determine the prevalence and consequences of pulmonary fibrosis in youth with thyroid carcinoma and lung metastases from Belarus who were treated with radioiodine ((131)I).

Methods: A total of 69 patients treated for juvenile thyroid carcinoma and lung metastasis with (131)I were assessed. A group of 29 patients without lung metastases and prior (131)I treatment served as controls.

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Aim: Differentiated thyroid carcinoma (DTC) in children and young adults is rare, can be aggressive, and often presents at advanced stages. In a population of young Belarusian patients with advanced DTC after the nuclear reactor accident at Chernobyl, we determined the activities that are as high as safely administrable (AHASA).

Patients And Methods: In 180 children and adolescents, we studied 133 courses of I-131 thyroid remnant ablation (median age at ablation, 14.

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Purpose: Differentiated thyroid carcinoma (DTC) in children and young adults is rare but often aggressive and in an advanced stage at diagnosis. In a cohort of young Belarusian patients with advanced DTC after Chernobyl we retrospectively studied parameters influencing the success of the postoperative (131)I therapy.

Methods: Included in the study were 136 patients (83 female, 53 male; median age 14.

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Purpose: The aim of this study is to report on a collective of 20 children from Belarus who had developed papillary thyroid carcinoma with pulmonary metastases after the Chernobyl disaster. In all children fractionated radioiodine therapy (RIT) was ceased before achieving complete remission due to a lack of further effects of (131)I therapy and an increased risk of pulmonary fibrosis.

Methods: The 20 children (12 girls) were treated with (131)I using 50 MBq/kg body weight for thyroid remnant ablation and 100 MBq/kg for further therapy in intervals of 5-12 months.

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Papillary thyroid cancer (PTC) among individuals exposed to radioactive iodine in their childhood or adolescence is a major internationally recognized health consequence of the Chernobyl accident. To identify genetic determinants affecting individual susceptibility to radiation-related PTC, we conducted a genome-wide association study employing Belarusian patients with PTC aged 0-18 years at the time of accident and age-matched Belarusian control subjects. Two series of genome scans were performed using independent sample sets, and association with radiation-related PTC was evaluated.

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Background: The Chernobyl accident resulted in an unprecedented number of radiation-induced thyroid cancers in young individuals as detected by national and international screening programs. The vast majority of thyroid malignancies were papillary carcinomas that, despite being similar by histopathology, displayed large variability in clinical course. The correlations between ultrasound (US) and clinicopathological features in young patients with radiation-induced thyroid cancer, however, have not been well studied.

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Papillary thyroid carcinoma (PTC) etiologically occurs as a radiation-induced or sporadic malignancy. Genetic factors contributing to the susceptibility to either form remain unknown. In this retrospective case-control study, we evaluated possible associations between single-nucleotide polymorphisms (SNPs) in the candidate DNA damage response genes (ATM, XRCC1, TP53, XRCC3, MTF1) and risk of radiation-induced and sporadic PTC.

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One of the lessons from Chernobyl's legacy on health impact beyond 20 years is not only how to detect and treat the patients with radiation-associated thyroid cancers but how to follow up those who received radioactive iodine treatment repetitively after surgery in order to monitor any recurrence/worsening and also how to predict the risk of secondary primary cancers for their lifetime period. To evaluate the possibility of second primary tumors after radioactive iodine treatment, we reviewed the reports on risks from both external and internal radiation exposure, especially at high doses during childhood through an internet service of the National Library of Medicine and the National Institutes of Health, PubMed by the end of June, 2007, together with our own experience of Chernobyl childhood thyroid cancers. Children who were internally exposed after Chernobyl accident have a long-term risk of well differentiated thyroid cancers.

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Purpose: To prospectively analyze the accuracy of various diagnostic criteria for cancer in solid thyroid nodules in children on the basis of gray-scale and power Doppler ultrasonographic (US) findings.

Materials And Methods: The study protocol was approved by the institutional review board, and patient's parents gave full informed consent. One hundred three consecutive pediatric patients with solid thyroid nodules were included in the study.

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The aim of this study was to estimate accuracy, intraobserver variability, and repeatability of thyroid volume measurement by ultrasound using conventional two-dimensional ellipsoid model (2D US) and manual planimetry of three-dimensional images (3D US). The sonographic images of 47 children with thyroid nodular pathology who were referred for thyroid surgery in Belarus were evaluated prospectively. Two-dimensional images were acquired using the ultrasound scanner with 7.

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