Comparative pathological characteristics of papillary thyroid carcinoma with second primary non-thyroid malignancies in the region affected by the Chernobyl accident

xlomafota13 shared this article with you from Inoreader Comparative pathological characteristics of papillary thyroid carcinoma with second primary non-thyroid malignancies in the region affected by the Chernobyl accident Via radioactive iodine Pathol Res Pract. 2021 Oct 19;228:153658. doi: 10.1016/j.prp.2021.153658. Online ahead of print. ABSTRACT The aim was to study the pathological features of papillary thyroid carcinoma diagnosed with or before second primary malignancy in patients exposed to post-Chernobyl exposure. The patients selected (n = 6559) were those exposed to radiation at the age of ≤ 18 years old and developed papillary thyroid carcinoma during the years 1990-2020. Of these, 2.1% (n = 140) had second p rimary malignancies. To compare the histopathological characteristics of papillary thyroid carcinoma in the group under analysis, 91% (n = 128) with sufficient data were included in further analysis. The control group was formed by matching patients with age at exposure to radiation, age at surgery, gender, and place of residence. Median age at exposure was 14 years old for both groups. Besides, no difference in tumour extension and histological features of papillary thyroid carcinoma was noted between patients with synchronous or metachronous primary malignant tumours. Nevertheless, the time lag to the diagnosis of papillary thyroid carcinoma was shortened in the group with metachronous when compared to patients with synchronous second primaries (p < 0.001). Independent differences between patients with second primaries and their matched peers included tumour size {OR (95%CI) = 0.89 (0.45; 1.04)}, multiple tumours {OR (95% CI) = 1.46 (0.86; 2.42)}, lymphatic vessel invasion (OR (95%CI) 0.92 (0.61; 1.53)), blood vessel invasion (OR (95%CI) 0.41 (0.10; 1.23) and presence of numerous psammomas (OR (95%CI) 0.73 (0.39; 1.31)). The possible influence of radiative iodine treatment for development of second primaries was analysed for the group of patients with metachronous malignancies using the same approach (84 patients were compared to 252 matched patients). Independent differences also included tumour size {OR (95% CI) 0.77 (0.45; 1.30)}, lymphatic vessel invasion {OR (95%CI) 0.75(0.43; 1.28)}, blood vessel invasion {OR (95%CI) 0.17 (0.01; 0.87)}. Besides, multiple tumours were revealed more frequently in patients with metachronous primaries (OR (95%CI) 1.92 (1.0; 3.62)). To conclude, patients exposed to Chernobyl irradiation with the development of papillary thyroid carcinoma and second primary malignancy have less biological aggressive pathological characteristics of their thyroid cancers. Accordingly, these patients were less frequently treated with post-su rgical radioactive iodine. Thus, 131I-irradiation may have negligible impact on the development of second primaries. PMID:34749211 | DOI:10.1016/j.prp.2021.153658 View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.