Endocrine Abstracts

Thyroid cancer in children at the age of 0–14 year is a rare case and according to 2018 y. sta-tistics, it comprise 4% of total endocrine system cancer. This article describes clinical case of 14 years old boy with the solid form of thyroid carcinoma and the diagnosis was based on the surgical tissue examination. According to planned ultrasound investigation 2 cm nodule was revealed in the left lobe of thyroid gland without involvement in lymph nodules. Blood test of TSH,FT4 hormones was in normal range. Fine needle aspiration (FNA) of the nodules shows thyroid follicular neoplasia. Microscopic investigation revealed a well-surrounded nodule with vascular invasion in capsule. Tumor was composed of round solid nests resembling filled up follicules,surrounded by fibrous/hyaline stroma. Focally nuclear features of papillary carcinoma was presented. Normal follicular structures was revealed arroud the capsule, but in the center of the nodule there was atypical cells with brisk miotoc activity. In the center of the tumor a solid but focally papillary structures was marked. It was performed an additional immunohistochemically (IHC) investigation using ‘dako’ antibodies : CEA,Calcitonin,Chromogranin A was negative. TTF1, Thyroglobulin and AE1/AE3-positive. It should be signed that poor expression of of the markers is revealed in the mitotic active areas, HBME1 –negative, CD56(-)negative. According to IHC analysis the medullary carcinoma has been excluded, although due to high mitotic activity of tumor cells differntial diagnosis was still followed between poorly differentiated carcinoma vs solid form of papillary carcinoma. It should be noted thyroid papillary carcinoma diagnosed according to nuclear signs of folliculocytes, which is better shown in FNA investigation. The IHC marker with high specifi-city and sensitivity doesn’t exist. The morphological criteria performed during investigation, because the cancer was well-surrounded and necrotic areas was not revealed. As the tumor was well-surrounded, there was no necrosis nuclear features of papillary carcinoma detected and given the patient’s age, we suggested a solid form of papillary carcinoma. A solid variant of papillary carcinoma may misdiagnosed by FNA investigation which shown more normal cells than tumor cells in smear. That is the first choice of pathological investi gation rather than FNA.