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PubMed2006

Treatment for acute lymphoblastic leukemia in children is associated with papillary carcinoma of thyroid, but not with thyroid disfunction.

AIM: The treatment of acute lymphoblastic leukemia (ALL) in children may cause sequelae, some appearing only at long-term follow-up. We investigated the thyroid gland morphology and the function of the pituitary-thyroid axis in a group of patients treated for ALL in childhood. METHODS: A cohort study was conducted at a tertiary medical center. Thirty-three children (22 males and 11 females; age: 11.9+/-3 years; range: 6 to 18 years) were studied. The mean age at the time of chemotherapy and prophylactic cranial irradiation (12-24 Gy) was 5.5+/-2.6 years (range: 1 to 14 years). The average length of the follow-up was 6.1+/-3 years (range: 2 to 12 years). Thyroid morphology (n=33) was evaluated by palpation and ultrasonography. Thyroid function (n=30) was evaluated measuring total T3 and T4, and by the thyrotrophin-releasing hormone (TRH) test. Prolactin secretion was assessed before and after injection of TRH to evaluate the diagnostic test accuracy. RESULTS: One out of the 33 children (3%) was found to have a papillary carcinoma of thyroid four years after ALL treatment. Thyroid function was normal in all the patients, however one case (3%) showed high TSH (9.2 microU/mL) and prolactin (37.5 ng/mL) basal levels, but normal responses to TRH (TSH = 17.8 microU/mL; prolactin = 82.3 ng/mL). These hormonal alteration were not confirmed at follow-up: TSH = 1.6 microU/mL and prolactin = 13.7 ng/mL. CONCLUSIONS: In this cohort of patients, the treatment of ALL was associated with one case of thyroid carcinoma, but it did not produce adverse effect on the thyroid function, at least after a follow-up lasted on average 6 years.

Adolescent↗
PubMed1986

[Hashimoto's thyroiditis with intra-thyroid production of a monoclonal antithyroglobulin autoantibody].

A 46-year old man had an Hashimoto's thyroiditis. The disease was particular by the voluminous goiter, associated with pressure symptoms and by the presence of a monoclonal Ig.G Kappa. Because of a possibly associated lymphoma of the thyroid, a total thyroidectomy was performed. Post-operative course showed a rapid and total disappearance of monoclonal Ig.G and antithyroglobulin autoantibodies. There was no pathological feature of thyroid malignancy. We could show that the monoclonal Ig.G bore an antithyroglobulin activity and that this monoclonal antithyroglobulin autoantibody was produced with in the thyroid. This case demonstrate that a monoclonal proliferation can arise from autoreactive B lymphocytes infiltrating the thyroid during Hashimoto's thyroiditis. Such a mechanism could explain, in some cases, the well-known association between lymphomas of the thyroid and Hashimoto's thyroiditis.

Antibodies, Monoclonal↗
PubMed1985

Chronic thyroiditis as a risk factor of B-cell lymphoma in the thyroid gland.

In order to contribute to the etiological study of thyroid lymphomas, the development of lymphomas in pre-existing chronic thyroiditis was statistically investigated. A total of 5592 female patients (older than 25 years) with chronic thyroiditis diagnosed between 1965 and 1982 at Kuma Hospital in Hyogo Prefecture were followed up until December 31, 1984. From a total of 45623 person-years, 8 new cases of primary thyroid lymphoma were observed (O), all of which were judged to be B-cell type from their immunological or histopathological characteristics. Since the expected number of cases with malignant lymphomas (E1) and the expected number of cases with thyroid lymphomas (E2) were 2.45 and 0.10, respectively, the O/E1 and O/E2 ratios were 3.3 (P less than 0.01) and 80.0 (P less than 0.001), respectively. The average follow-up interval for the patients with thyroid lymphoma was 9.2 years. In the reference group, consisting of cases with Basedow's disease, an increased risk of thyroid lymphoma was not observed. The present results suggest that autoimmune reactions with a notable lymphocytic infiltrate may play an important role in the etiology of lymphomas in the thyroid gland.

Adult↗
PubMedDate not supplied

[Thyroglobulin biosynthesis and the content of thyroglobulin polyribosomes of the thyroid gland cells in the normal state and in various types of thyroid pathology].

The content of polyribosomes in human thyroid cells was studied in health and different forms of thyroid pathology. In thyroid pathology, thyroglobulin (TG) polyribosome content in thyroid cells diminished in the following order: diffuse toxic goiter greater than mixed euthyroid goiter greater than nodular toxic goiter greater than Hashimoto's goiter and complete absence of TG synthesizing polyribosomes in thyroid cancer and congenital goiter cells. No correlation was revealed between polyribosome TG content and thyroid function. It is inferred that impairment of TG biosynthesis in thyroid diseases is related to the decreased content of polyribosome TG in thyroid cells.

Humans↗
PubMedDate not supplied

Experimental studies concerning the mechanism of the thyroid-pineal interrelationship. I. The action of the pineal peptides on the thyroid gland.

Subcutaneous administration of a pineal polypeptide extract, "Crinofizin", to adult male Wistar rats having the thyroid function inhibited by prolonged administration of MTU, has important effects on both the whole organism (slightly correcting the weight increase rate, loweri g cholesterolemia) and the thyroid gland (reducing thyroid hyperplasia and playing a part in various stages of thyroid hormones metabolism). Thus under pineal treatment one can observe a clear tendency to return to the normal values of the thyroid parameters strongly modified by MTU, as RIC, intrathyroid proteic iodine, tissue thyroid hormones distribution, blood PBI and total T4. It appears that these effects of pineal peptides are induced directly on the thyroid and/or via the hypophyso-thyroid axis which they intercept and equilibrate (moderate).

Animals↗
PubMed1994

[Painful chronic thyroiditis. A rare cause of thyroid pain].

The usual clinical presentation of Hashimoto's chronic lymphocytic thyroiditis is a firm and painless goiter. We report two atypical observations with painful symptoms. Case 1: a 33 year old woman with a two months history of L-thyroxine treated primary hypothyroidism associated with elevated antithyroglobulin and antithyroperoxydase antibodies (respectively 36.000 and 7.000 U/l, normal values < 100 U/l) presents with anterior cervical pain. She is euthyroid, but displays biological inflammatory syndrome. Neck ultrasonography reveals low amplitude echoes of the thyroid gland. Antithyroid antibodies remain at high titers. After failure of NSAI drugs, prednisolone (oral 30 mg/day for 10 days, followed by degression) allows rapid disappearance of both pain inflammatory syndrome. When treatment was stopped pain recurred and required steroids for 3 months. After one year, the patient is painless and only receives L-thyroxine. Case 2: a 36 year old woman is referred for anterior neck pain, fever and hypothyroidism. Biological inflammation is also noted. High levels of antithyroglobulin and antithyroperoxydase antibodies are found. Thyroid uptake was maintained. L-thyroxine and prednisolone (oral 20 mg/day) therapies are associated with rapid pain relief. After two months, steroids are stopped. The patient remains normothyroid under L-thyroxine. Antithyroid antibodies persist at high levels. Other aetiological diagnosis of painful thyroid include acute infectious thyroiditis, cancers, intracystic hemorrhages and mainly subacute De Quervain's thyroiditis. Beyond clinical symptoms (revelation with hypothyroidism), persistent scintiscan uptake and prolonged elevated levels of antithyroglobulin and antithyroperoxydase antibodies remain the strongest arguments in favor of the 33 reported cases of painful Hashimoto's chronic lymphocytic thyroiditis. Eventually, among various therapies used, steroids in conjunction with thyroid hormones, seem the most efficient.

Adrenal Cortex Hormones↗
PubMed1996

Optimal laboratory testing for diagnosis and monitoring of thyroid nodules, goiter, and thyroid cancer.

Optimal use of laboratory tests to diagnose and monitor patients with goiter, thyroid nodules, or thyroid cancer requires an appreciation of the pathophysiologic factors implicated in thyroid hyperplasia and neoplasia: growth factors (especially thyrotropin, TSH), growth-stimulating immunoglobulins, activating mutations of the TSH receptor, and other oncogenic transformations. In patients with diffuse goiter and thyroid nodules, serum TSH measurement in a highly sensitive assay excludes both primary hypothyroidism and common causes of thyrotoxicosis. In selected patients, screening for anti-thyroid peroxidase with or without anti-thyroglobulin antibodies can confirm the diagnosis of autoimmune thyroiditis. Serum calcitonin measurement is appropriate only when medullary thyroid carcinoma (MTC) is clinically suspected. Laboratory testing is essential in management of thyroid carcinoma patients after primary surgical therapy. Serum TSH measurement is vital to ensure that thyroxine replacement and TSH suppression are adequate in treatment of epithelial cancers. Serial monitoring of serum thyroglobulin (Tg) can detect tumor recurrence and quantify tumor burden. Interpretation of serum Tg results requires an appreciation of certain technical considerations (e.g., anti-Tg antibody interference) and the patient's concurrent TSH status. Periodic serum Tg measurements and 131I scans are complementary monitoring techniques. Serum calcitonin measurement and screening for ret protooncogene mutations are both valuable for identifying individuals with MTC.

Diagnosis, Differential↗
PubMed1998

Thyroid volumetric measurement and quantitative thyroid scintigraphy in dogs.

Thyroid volumetric measurement combined with quantitative 99mTc-per-technetate thyroid scintigraphy was performed in 62 clinical canine patients having suspected thyroid abnormalities. Euthyroid dogs (n = 22) had a total thyroid size of 3.60 +/- 1.36 cm3, the thyroid/salivary gland region of interest (ROI) ratio was 2.01 +/- 0.55, the thyroid/background ROI ratio was 3.86 +/- 0.90, and 20-min thyroid radioactivity uptake was 1.17 +/- 0.71% of the injected dose (I. D.). By Student's unpaired test, thyroid size of the hypothyroid group (n = 36) was not statistically different from that of the euthyroid dogs, but all other quantitative data (e.g., thyroid/salivary gland ROI ratio = 1.08 +/- 0.56, thyroid/background ROI ratio = 2.32 +/- 0.70, and 20-min thyroid radioactivity uptake = 0.34 +/- 0.22% of the I. D.) were significantly (p < 0.001) lower in hypothyroid than in euthyroid dogs. Evaluating the above-listed quantitative data of separated thyroid lobes by Student's paired test, there was no significant difference between the left and the right lobe either in the euthyroid or in the hypothyroid group.

Animals↗
PubMed1991

Thyroid stimulating and thyrotrophin binding-inhibitory immunoglobulin activity in patients with systemic lupus erythematosus having thyroid function abnormalities.

In order to determine whether thyroid function abnormalities seen in patients with systemic lupus erythematosus (SLE) are associated with autoantibodies directed against the TSH receptor, 28 patients with SLE who demonstrated abnormal thyroid function tests were evaluated for the presence of anti-TSH receptor antibodies. Anti-TSH receptor antibody activity was evaluated by assessing cAMP production in vitro in FRTL-5 (rat thyroid) cells (TSI) and the ability of the subjects' IgG to block the binding of thyrotrophin to its receptor in vitro (TBII). Complete thyroid function tests, including TRH testing, also were performed. Ten of the 28 patients demonstrated TSI activity, ranging from 133% to 183% of control. Five patients also had evidence of TBII activity, ranging from 22% to 90% inhibition (of control TSH binding levels), with 2 patients having evidence of both types of antibodies. Neither the TSI nor TBII activity in these patients was associated with the abnormal thyroid function tests. However, there were significantly more patients with TBII activity who had elevated TSH levels (3 of 4 vs 1 of 24, p less than 0.05), suggesting a potential physiologic response to TSH receptor blockade. These results indicate that patients with SLE and thyroid function abnormalities can demonstrate TBII and TSI activity in their serum. However, these antibodies do not necessarily correlate with specific abnormalities of thyroid function.

Antibodies, Antinuclear↗
PubMed2005

Resistance to thyroid hormone in a patient with thyroid dysgenesis.

We report a patient with the unusual coincidence of two rare congenital disorders, lingual ectopy of the thyroid gland and resistance to thyroid hormone (RTH), resulting in impaired thyroid hormone production and action, respectively. The proposita had a positive thyrotropin (TSH) newborn screening test (350 mU/L, confirmed) with normal thyroxine (T4) and no clinical signs of hypothyroidism. A scintiscan revealed lingual but no orthotopic thyroid tissue. Levothyroxine (LT4) replacement failed to reduce TSH and was discontinued after four months owing to significantly elevated free T4. Her physical and mental development was unremarkable, and she was considered to be clinically euthyroid throughout childhood, even though she received either no T4 or a dose insufficient to lessen hyperthyrotropinemia. At the age of 15 years, T4 was gradually increased to a supraphysiological dose of 300 microg/d, resulting in the normalization of the serum TSH level, and subjective improvements in her ability to concentrate. The proposita's mother was clinically euthyroid, had a palpable diffuse goiter, and thyroid function tests consistent with RTH. This diagnosis was confirmed by detection of a heterozygous mutation (R320H) in the thyroid hormone receptor-beta (TR-beta) gene found in both the proposita and her mother. Under the high-dose T4 regimen, the patient's TSH and free T4 values resembled those of untreated patients with TRbeta R320H mutation, suggesting that a compensated state could be achieved, at least at the pituitary level. In the proposita, treatment of hyperthyrotropinemia is clearly mandatory because of potential complications inflicted by TSH-stimulated growth of the lingual tissue. To our knowledge, this represents the first report of congenital hypothyroidism secondary to thyroid dysgenesis complicated by coincidental RTH.

Adolescent↗
PubMed1988

Occurrence of thyrocyte HLA class II expression in a wide variety of thyroid diseases: relationship with lymphocytic infiltration and thyroid autoantibodies.

The proteins of the major histocompatibility system (HLA in humans) play an essential role in the regulation of immune responses due to their involvement in the presentation of antigen to T lymphocytes. Thyroid follicular cells (thyrocytes) from patients with Graves' disease and Hashimoto's thyroiditis demonstrate increased expression of HLA class I and aberrantly or inappropriately express class II antigens, a phenomenon that may play an important role in the pathogenesis of these autoimmune diseases. To establish if these changes in the expression of HLA molecules are characteristic of thyroid autoimmune disease, the immunopathological features (including class I and class II antigen expression) of 100 thyroidectomy specimens from patients with nonautoimmune thyroid disease were studied by indirect immunofluorescence, and the results compared with the findings in specimens from 14 patients with Graves' disease and 12 subjects undergoing laryngectomies for carcinoma. Increased class I product expression was found in 61% of all tissues studied, with maximal occurrence in papillary carcinomas (100%) and Graves' disease (86%), but it was also detected in 50% of the glands containing nodular lesions and in 16% of the control glands. Inappropriate class II molecule expression was found in Graves' disease (71%), hyperplastic nodules (53%), multinodular glands (44%), papillary carcinomas (38%), and 16% of the control glands. In summary, an increase in inappropriate HLA class I and class II expression was very common in nonautoimmune thyroid glands, but it generally occurred in the context of lymphocytic infiltration and thyroid autoantibodies (i.e. focal thyroiditis). Multiple correlation analyses of these 4 phenomena indicated heterogeneity in the mechanism leading to the inappropriate expression of thyrocyte class II antigens in the different conditions studied.

Adolescent↗
PubMed2005

[Thyroid transcription factors involved in the thyroid hormones biosynthesis].

The thyroid hormone biosynthesis is dependent on the level of the expression and the correct action of the basic proteins involved in this process: TSH receptor (TSH-R), sodium-iodine symporter (NIS), thyroglobulin (Tg), thyroid peroxidase (TPO) and iodothyronine deodinases type 1 (D1) and type 2 (D2). Transcription of the genes coding these proteins is regulated by TSH via cAMP cascade. Despite the thyroid-specific transcription factors are necessary for the transcription regulation of TSH-R, NIS, TG, TPO, DIO1 and DIO2 genes. Three thyroid transcription factors Titf1/Nkx2-1, Foxel and Pax8 seem to be essential for thyroid development, growth and function. Disturbances of the expression of these transcription factors and their co-operation could be responsible for the congenital thyroid gland disorders as well as in thyroid cancerogenesis.

Animals↗
PubMed1996

Immunohistochemical loss of thyroid peroxidase in papillary thyroid carcinoma: strong suppression of peroxidase gene expression.

It is believed that qualitative changes in thyroid peroxidase (TPO) cause decreased enzyme activity in differentiated thyroid carcinoma. To re-evaluate TPO expression in thyroid cancer, TPO mRNA expression was compared with TPO protein expression in 38 samples of thyroid tissue obtained from patients with various thyroid diseases. In Northern blot studies, while TPO mRNA was highly expressed in tissues from all 18 benign lesions, it was strongly suppressed in 14 tumours, including 12 out of 12 papillary carcinomas, one of seven follicular carcinomas, and one medullary carcinoma. TPO mRNA was not detected in six carcinomas, of which four were papillary, one follicular, and one medullary, by the usual Northern blot method. The 14 cases with strong underexpression of TPO mRNA were very weakly stained with anti-TPO monoclonal antibody 38E, whereas all 18 benign tissues were strongly stained. Moreover, a comparative study of TPO expression by Northern blot and immunohistochemical analysis revealed a positive correlation between TPO mRNA expression and the staining intensity of TPO protein. These results suggest that strong suppression of TPO mRNA transcription causes low TPO activity in papillary carcinoma; immunohistochemical loss of TPO may be a useful diagnostic marker. TPO mRNA expression in differentiated thyroid carcinomas did not always correlate with the mRNA expression of thyroglobulin, thyroid stimulating hormone receptor, and thyroid transcription factor 1.

Biomarkers, Tumor↗
PubMed1999

Ascidian homologs of mammalian thyroid peroxidase genes are expressed in the thyroid-equivalent region of the endostyle.

The endostyle is a pharyngeal organ for the internal filter feeding of urochordates, cephalochordates, and larval lamprey. This organ is also considered to be homologous to the follicular thyroid gland of higher vertebrates. Thyroglobulin (Tg) and thyroid peroxidase (TPO) are specifically expressed in the thyroid gland of higher vertebrates, and they play an important role in iodine metabolism for the synthesis of thyroid hormones. Previous histochemical observations showed that iodine-concentrating and peroxidase activities were detected in zones 7, 8, and 9 of the ascidian endostyle, suggesting that these zones contains cells that are equivalent to those in the vertebrate follicular thyroid. In order to investigate the molecular developmental mechanisms involved in the formation and function of the endostyle, with special reference to the evolution of the thyroid gland, in the present study, we isolated and characterized cDNA clones for TPO genes, CiTPO from Ciona intestinalis and HrTPO from Halocynthia roretzi. Northern blot and in situ hybridization analyses revealed that the expression of the ascidian TPO genes was restricted to zone 7, one of the elements equivalent to the thyroid. These results provide the first evidence at the gene expression level for shared function between a part of the ascidian endostyle and the vertebrate follicular thyroid gland. J. Exp. Zool. ( Mol. Dev. Evol. ) 285:158-169, 1999.

Amino Acid Sequence↗
PubMed1997

p53 mutations in childhood thyroid tumours from Belarus and in thyroid tumours without radiation history.

Mutations in the p53 tumour-suppressor gene (exons 5-8) were investigated in 31 Belarussian childhood thyroid tumours (24 cases of papillary thyroid carcinoma, 3 benign tumours and 2 cases each of thyroiditis and goiter); 33 thyroid tumours from juveniles and adults without radiation exposures (25 carcinomas of various histological types, including 11 papillary carcinomas and 8 adenomas) and 6 tumours from adults (4 papillary carcinomas, 1 adenoma, 1 goiter) served as controls. The mutational spectrum of p53 differed greatly between the childhood thyroid carcinomas from Belarus and the control groups. In the control groups of 29 malignant thyroid tumours, 7 different mutations were detected on exons 5-8, none of which occurred among the 15 papillary carcinomas in this group. Five mutations were found in tissue samples of the 24 childhood papillary carcinomas, and they were all the same p53 point mutation (CGA --> CGG) on codon 213 of exon 6. To determine whether this mutation is simply a polymorphism or whether it is specific to the tumour cells, laser-assisted microdissection was applied to collect various areas of tumorous and non-tumorous cells (10-20 cells per sample) from each paraffin-embedded tissue section of 8 of the papillary thyroid carcinomas. Using PCR-SSCP and sequence analysis on these cells, the very same p53 mutation on codon 213 was detected in various microdissected tumour samples of 2 cases, but it was not found in any microdissected non-tumorous sample. The exclusive occurrence of this p53 mutation in selective microdissected samples of tumour cells, even as homozygous mutation in 1 case, reflects a distinct tumour heterogeneity within papillary childhood thyroid carcinomas.

Adolescent↗
PubMed1992

HTLV-I infection in patients with autoimmune thyroiditis (Hashimoto's thyroiditis).

To investigate the possible relationship of HTLV-I virus infection to autoimmune thyroid disease, we examined, firstly, the frequency of HTLV-I seropositivity among patients with Hashimoto's thyroiditis and, secondly, the frequency of Hashimoto's thyroiditis in patients with HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP). Of 144 patients with Hashimoto's thyroiditis in the Tokushima and Kochi Prefectures, Japan, 9 (6.3%) were positive for serum HTLV-I virus antibody 2 of whom were confirmed histologically to have Hashimoto's thyroiditis. This percentage is significantly higher (P < 0.01) than the estimated prevalence (2.2%) of HTLV-I carriers among the general population in this region. Of 9 patients with HAM/TSP, 3 (33.3%), including 2 biopsy-proven cases, had evidence of Hashimoto's thyroiditis. This proportion is apparently much higher than the prevalence (1.7%) of Hashimoto's thyroiditis in the general population. These findings suggest that HTLV-I virus may be related to the development of Hashimoto's thyroiditis.

Adult↗
PubMed1996

Effect of melatonin on the anuran thyroid gland: follicle cell proliferation, morphometry, and subsequent thyroid hormone secretion in vitro after melatonin treatment in vivo.

The thyroid gland controls the progress of metamorphosis, although other hormones influence metamorphic rate, including melatonin, which may coordinate metamorphosis with seasonal and light conditions. Melatonin directly antagonized the action of thyroxine (T4) in promoting regression of tadpole tail tips in vitro, and this study sought to determine if it affects the thyroid axis of tadpoles as well. In an experiment sampling at 8-hr intervals for 24 hr, after melatonin treatment (15 micrograms/day for 12 days) of premetamorphic Rana pipiens tadpoles at approximately 1100 hr on 18L:6D, thyroid follicle cell height and lumen diameter were lowered by melatonin, but follicle cell proliferation was not significantly depressed. In a second experiment conducted under the same conditions, but sampling at 3-hr intervals for 24 hr, melatonin significantly lowered follicle cell labeling index and suppressed its ultradian (7.6 hr) rhythm, while shifting the peak of follicle lumen diameter to the dark instead of the light. Thus, melatonin tended to depress the thyroid of young tadpoles and suppress or shift its rhythms. Melatonin (10 micrograms/day for 5 days) injected into prometamorphic Rana catesbeiana tadpoles at 1930 hr on 18L:6D significantly altered subsequent in vitro thyroid function as determined by radioimmunoassay of media collected at intervals for 54 hr from cultured thyroids of injected control and melatonin groups, and a noninjected control group. Melatonin decreased T4 secretion during the first 30 hr, but not during the last 24 hr of culture, suppressed 3,5,3'-triidothyronine (T3) secretion for 12 hr, and then raised T3 output into the media above the control for the remainder of the culture period, increasing the T3:T4 ratio. Injection alone increased both T3 and T4 secretion for the first 30 hr, but did not change the T3:T4 ratio. The findings show that exogenous melatonin administered in vivo significantly modulated thyroid activity and morphometry directly and/or indirectly and comprise the first demonstration of an effect of melatonin on the amphibian thyroid gland.

Animals↗
PubMed1994

Thyroid dose assessment for the Chernigov region (Ukraine): estimation based on 131I thyroid measurements and extrapolation of the results to districts without monitoring.

Based on the results of 131I thyroid activity measurements in three districts of the Chernigov region (Ukraine), individual doses were calculated and an approach of the age dependence of the average thyroid exposure was derived. Using the relationships between the thyroid doses and the 137Cs deposition as well as the location relative to the Chernobyl Nuclear Power Plant (NPP), age-dependent average thyroid doses were extrapolated also for those settlements of this region where no monitoring measurements have been carried out. The highest doses were found in the west of the region with the lowest distance to the Chernobyl NPP. In this part, the highest mean of the thyroid dose in a settlement was 3.3 Gy for infants and 0.5 Gy for adults. The collective thyroid dose was 31,000 and 27,000 person-Gy for children and adults, respectively. Based on this assessment, 140 and 21 excess thyroid cancer cases are predicted for children and adults, respectively. In the years 1989 to 1991, in the whole contaminated territory of the Ukraine 0.4-1.2 cases per 100,000 children were observed. Although the absolute numbers are very small, this indicates the possibility of an increase in thyroid cancer morbidity among children. The same trend also seems to be indicated in the Chernigov region. A careful epidemiological study in the future is necessary to enable a final evaluation of radioinduced cancers in this region.

Adolescent↗