Thyroid cancer in Belarus after Chernobyl

International Congress Series, 2002

The Chernobyl accident in April and May of 1986 promoted thyroid carcinomas in 1500 patients who were exposed to radiation at the age group under 18. The common type of malignancy was papillary cancer (93.5%). For the period from 1990 to 2000, thyroid carcinomas were diagnosed in 674 children (age group under 15), in 262 adolescents (age group between 15 and 19) and in 564 young adults (age group from 19 to 33). The highest number of thyroid malignancies in children and adolescents was diagnosed in Gomel and Brest oblasts located closer to the Chernobyl Nuclear Power Plant. For 15 years (1986 -2000), spontaneous (non-radiogenic) thyroid carcinomas appeared only in 17 children. Thyroid cancer promoted by radiation in children possesses the behavior to form the regional (73%) and distant (16.6%) metastases, mainly in lung. As a result of performed risk analysis for the cohort exposed at the age group under 18, the following values were obtained: 1.93 (1.79 -2.06) per 104 PYGy for the absolute risk coefficient, and 37.66 (35.06 -40.26) per Gy for the excess relative risk coefficient. D

Sozial- und Pr�ventivmedizin SPM, 1994

Journal of radiological protection : official journal of the Society for Radiological Protection, 2006

Our objective is to assess the regional and temporal dependences of the baseline cases contributing to thyroid cancer incidence among those exposed in childhood or during adolescence in Belarus and Ukraine after the Chernobyl accident. Data are analysed for Kyiv and Sevastopol City and the 25 oblasts (regions) in Ukraine, and for Minsk and Gomel City and the 6 oblasts in Belarus. Average thyroid doses due to the Chernobyl accident were assessed for every birth year in the period from 1968 to 1985. Case data pertain to people who underwent surgical removal of thyroid cancers during the period 1986 to 2001 and who were allocated to their place of residence at the time of the accident. The 35 oblasts/cities were subdivided into an upper, middle and lower group of baseline thyroid cancer incidence. Poisson regressions were performed to estimate age, time and gender dependences of the baseline incidence rates in the three groups. The majority of oblasts/cities with high average doses and...

Assessment of incidence and mortality for thyroid cancers carried out for the Belarusian population is described in the present report. It is found that in the period of 1987-2000 about 4,400 radiation-induced thyroid cancers appeared in Belarus: 692 cancers among children and 3,709 cancers among adolescents and adults. The number of lethal thyroid cancers in this period of time in Belarus was assessed as about 350 cases. The excessive absolute risk, EAR, of thyroid cancer incidence assessed for the period of 1987-2000 on the basis of given data on the morbidity and the assessed collective thyroid dose of irradiation is (2.5 – 5.0) per 10 4 PYGy. The EAR value of thyroid cancer mortality is assessed as (0.20 -0.40) per 10 4 PYGy. The excessive relative risk, ERR, of thyroid cancer incidence is assessed as (11.2 – 22.4)/Gy. The radiation risks of thyroid cancers found in the present report are higher than the risk coefficients established for atomic bomb survivors that were irradiate...

Radiation Research, 1998

The Journal of Clinical Endocrinology & Metabolism, 1997

After the Chernobyl nuclear accident (April 26, 1986), childhood thyroid carcinoma had a great increase in Belarus and Ukraine, as a consequence of the exposure to iodine radioactive fallout. The epidemiological and clinical features of the disease were studied in 472 patients less than 21 yr old at diagnosis, with differentiated thyroid carcinoma, representing 97.7% of all thyroid carcinomas diagnosed in Belarus between May, 1986, and December, 1995. The results were compared with those of 369 subjects of the same age group, with naturally occurring thyroid carcinoma, observed in Italy and France.

Arquivos Brasileiros de Endocrinologia & Metabologia, 2007

Thyroid cancer in children is usually rare, but in the individuals exposed to radiation risk of disease increases considerably. After the Chernobyl accident in 1986, an over 10-fold maximal elevation in the incidence of thyroid cancer was registered about a decade later, cumulatively resulting in more than a thousand of newly diagnosed cases in children who lived in the territories of Belarus, Russia, and Ukraine affected by radioactive fallouts. Experience from the epidemic substantially promoted knowledge in clinical pediatric oncology, pathology and basic sciences. This article overviews epidemiology, clinical features, results of treatment and followup of childhood patients with radiation-induced Chernobyl thyroid cancer in comparison to sporadic cases diagnosed at present. In addition, we discuss general issues of pathology and molecular findings in childhood thyroid carcinomas. (Arq Bras Endocrinol Metab 2007;51/5:748-762) RESUMO Câncer de Tiróide na Infância na Bielorússia, Rússia, e na Ucrânia, Após Chernobil e Atualmente.

STEM CELLS, 2009

Starting in 1990, an increasing number of children in regions adjacent to the site of the Chernobyl nuclear accident have been diagnosed as suffering from thyroid cancer. Using available data up to 1994, the geographical distribution, time and cohort trends, age distribution and other characteristics of this epidemic are reviewed. The results show that the geographical distribution is similar to that of iodine-131 after the nuclear accident. When looking at cohorts of children born in the same years, one can see that the incidence has been increasing steadily since 1990; deviations from this pattern might be explained by active case finding. A causal relationship with the Chernobyl accident appears the most likely interpretation of these results. Possible modifying factors should, however, be examined closely. Stem Cells I997;l S(suppl2):251-254

Histopathology, 1992

Recently, an impressive increase in malignant thyroid tumours has been observed among children less than 15 years of age living in the Republic of Belarus at the time of the nuclear accident of Chernobyl in 1986. More than half of these patients lived in the region of Gomel, nearest to Chernobyl. Because of the very short time interval between the accident and the tumour occurrence an independent review of the available histopathological material was done. Out of 101 cases diagnosed as thyroid cancers, we reviewed slides of 93 cases and agreed the diagnosis of malignancy in 92.5%. Of these tumours 96.5% were papillary carcinomas, 61.5% were moderately or poorly Merentiated. Extrathyroidal extension was observed in 60.5%, regional lymph node metastases in 74% and distant metastases in 7%. One of the patients died from lung metastases. Our results confirm that the neoplasms increasingly diagnosed between 1986 and 1991 among children of this region are thyroid carcinomas. In addition, we correlate several histopathological findings with sex and age of the patients and other parameters, and compare the results with data from other studies.

Journal of Radiological Protection, 1999

The paper presents the analysis of thyroid cancer incidence in the territories of Russia that were most contaminated after the Chernobyl accident. Incidence data in the Bryansk, Kaluga, Orel and Tula regions (5,298 thousand persons) are used. Information on incidence has been obtained from regional oncological dispensaries (state health institutions involved in diagnosis and treatment of malignant neoplasms). Altogether, 2,599 cases of thyroid cancer are considered from 1982 to 1995. Of them, 62 cases were among children and adolescents and 143 among the population who were children and adolescents at the time of the accident in 1986. The study is performed for both sexes. The study compares the distribution of thyroid cancer cases by age at diagnosis and age at exposure. It has been shown that since 1991 the age structure of the incidence has changed significantly with the growing proportion of cases among children and adolescents. The change in the structure occurred due to the radiation factor, specifically as a result of exposure of thyroid to incorporated 131 I. A dependence of risk of cancer on age at exposure has been derived. For children of 0-4 years at exposure the risk of induction of radiogenic thyroid cancer is 6-10 times higher than in adults. On the average, the risk coefficient in children and adolescents at the time of exposure is about 3 times higher than that in adults. The analysis of time trend in thyroid cancer incidence has shown that the incidence rate observed in the period from 1991 to 1995 in the age groups up to 25 years is expected to be maintained in the near future.