Clinical study of thyroid cancer among a pediatric population born after Chernobyl (first report)
6069 Background: To evaluate the clinical and patologic results of surgical treatment of children born after Chernobyl and to compare these findings with well-known data of the group of patients who were children at the time of Chernobyl. To compare the clinical and pathologic features of thyroid cancer of children born after the Chernobyl versus those born prior to 1986. Methods: Comparison of clinical and pathologic result of surgical treatment of 141 patients born after Chernobyl (Group 1) and 589 patients (Group 2) aged 0–18 at the time of the disaster (1986) among the single institution clinical cohort within years 1995–2005. Results: In Group 1 there were 31 cancers (22%) vs. 243 (41%) in Group 2 (p<0.05 between Group 1 and Group 2). The rate of extrathyroid invasion was 69% vs. 36% (p<0.05 between Group 1 and Group 2). In Group 1, 17/21(80%) patients with extrathyroid invasion were found to have regional neck metastases (8 unilateral, 9 bilateral).The mean age in this subgroup was 13.4 ± 2.11 years but in the “benign subgroup” of Group 1 the mean age is 16.2 ± 0.77 years.In Group 2, 49/88 (55%) patients with extrathyroid invasion only had regional metastases. The mean age in this subgroup is 31.1 ± 4.7 years (p<0.05 between Group 1 and Group 2). We found cancer multifocality in 1 patient (3%, Group 1) vs. 55 (23%, Group 2).There were 19 cases (13.5%) of atypical adenomas in Group 1 vs. 46 (8%) in Group 2 (p<0.05 between Group 1 and Group 2). Histological types: solid follicular variant of papillary carcinoma (typical for radiation-induced children carcinomas with short latency) was found in 3 cases in Group 1 (9.5%) vs. 76 (31%) in the Group 2 (p<0.05 between Group 1 and Group 2). There was only one case of follicular thyroid cancer in Group 1 (3%) vs. 9% in Group 2. We did not find any relationship of cases of cancer in Group 1 to the Chernobyl-polluted area (only 3 patients − 10% from the nearest to Chernobyl regions) vs. 192 patients (80%) in Group 2 (p<0.05 between Group 1 and Group 2). Among patients with tumors of uncertain malignant potential 9 patients (6%) were from Chernobyl-polluted area vs.72% in Group 2 (p<0.05 between Group 1 and Group 2). Conclusions: Our data demonstrates higher likelihood of aggressive well-differentiated thyroid cancer among a pediatric population independently from Chernobyl irradiation and connected with another etiological factors of genesis of tumor.The solid-follicular variant of papillary cancer and multifocality are typical for radiation-induced carcinoma in children. No significant financial relationships to disclose.