21. Papillary thyroid carcinoma in children and adolescents: state-of-the art in post-chernobyl belarus

Abstract

<h3>Aims</h3> To present wide-ranging clinicopathological data of papillary thyroid cancer in children and adolescents who have no apparent link to previous irradiation or other aetiological cause (genetic predisposition or contact with any well-known canceri-genic agent). Ninety-four consecutive surgically treated patients aged 4–18 years were investigated. <h3>Results</h3> In the majority of patients the carcinoma had already broken through the organ's capsule and afflicted lymph nodes of both paratracheal (level VI) and parajugular (level II–IV, in a few cases level V) zones (pT3bN1bM0, <i>n</i>=27; 28.4%). Median tumour size was 12 (range 1–100)mm. Classical variant of papillary thyroid carcinoma was the most common subtype (43; 45.7%) followed by follicular (20; 21.3%) and tall cell (10; 10.7%) variants. Incidence of lymph node metastases at presentation was 71.3% (N1a 20.2%, N1b 51.1%) and 9.6% of patients had bilateral N1b involvement. Classical architectonic (<i>p</i> < 0.01), nodular type of lymphoid infiltration (<i>p</i> < 0.01), lymph vessels invasion (<i>p</i> < 0.01) and infiltrative growth or diffuse (diffuse sclerosing or diffuse sclerosing-like) involvement were associated (<i>p</i> < 0.01) with lymph node metastases. <h3>Conclusion</h3> Papillary thyroid carcinoma in childhood and adolescence was most commonly diagnosed in patients aged 12–17 years and was usually >10mm in size (53; 56.4%). Infiltration of soft tissues (36; 38.3%) and intrathyroid lymphatic vessels by tumour complexes and psammoma bodies (59; 62.8%) was common. It is also typical that the tumour undergoes secondary scarring located mostly in central parts (massive fibrosis involves 30–70% of neoplasm volume observed in 25 cases; 26.6%). The tumours spread regionally. Finally, autoimmune thyroiditis appears to play a role in the background pathology (26; 27.6%).