Histopathological characteristics of childhood thyroid cancer in Gomel, Belarus

Abstract

We reviewed histopathologically I 9 cases of childhood thyroid cancer occurring between 1991 and 1994 among 14,396 screening subjects in Gomel, Republic of Belarus, the region most severely radio-contaminated by the Chernobyl nuclear power plant accident in 1986. The patients were I3 girls and 6 boys with a mean age of 10.6 years. The mean age at the time of the accident was 3.2 years. Mean tumor diameter was I 6 mm, and all cases were papillary carcinoma with various amounts of solid component. Psammoma bodies and stromal fibrosis were encountered to some extent in almost all cases. The tumors were highly prone to local invasion and regional lymph-node metastasis. No morphological evidence for radiation-induced cancer was obtained in these cases. I3'Cs levels were relatively high in the patients' bodies and in the soil at the places of domicile. However, there was no dose-response relationship between cancer prevalence and radioactivity. These facts suggest that the incidence of aggressive pediatric thyroid cancer is extremely high in Gomel, where most of the children were exposed to a low level of radioactivity over a long time after the accident. At present, however, no definite conclusion can be drawn on the relationship between cancer occurrence and radioactive contamination.

Pediatric Thyroid Cancer in Europe: An Overdiagnosed Condition? A Literature Review

“…The histological changes found were similar to those reported in the literature, with predominant cases of papillary thyroid cancer [5,11,[22][23][24]31].…”

“…After the April 1986 nuclear accident, pediatric thyroid cancer presented an increased incidence, especially in countries adjacent to Chernobyl. This increase in incidence is not determined by a more intensive initial screening but the emergence of more new cases, most likely determined by external factors (nuclear radiation) [22,24]. The new cases were found to be more aggressive, with significant local invasion and distant metastases [5,22,38].…”

“…Most radiation-induced cases have occurred in children who were under 5 years of age at the time of exposure to radiation [22][23][24]. These tumors were much more aggressive than those that appeared spontaneously, with a short latency period between the time of exposure and their onset, and histologically they were almost exclusively papillary thyroid carcinomas (predominantly follicular variants but pure papillary forms are present), but also cases of follicular thyroid cancer, medullary thyroid cancer, and rare cases of anaplastic thyroid cancer [5,[22][23][24]26,29,31,40,41]. Medullary thyroid cancer occurs especially in patients with MEN2B syndrome [8,16].…”

Thyroid Cancer: Molecular Characteristics of Radiation-Associated Papillary Thyroid Cancer, with a Special Reference to of Atomic Radiation Exposure

“…In addition, adult-onset PTC among A-bomb survivors included infrequent follicular variants and no solid variants, which are subtypes of PTC. For children internally exposed in Chernobyl, however, malignant thyroid tumors are principally PTC, and include frequent follicular variants and solid variants [9][10][11], but these morphologic characteristics may have been related to low dietary iodine levels and childhood cancer types [12].…”