Cribriform-morular variant of papillary thyroid carcinoma at pediatric age - case report and review of the literature.

Cribriform-morular variant of papillary thyroid carcinoma (CMV-PTC) is a rare tumor, which exceptionally occurs at pediatric age. CMV-PTC may develop in patients with familial adenomatous polyposis (FAP) or may be a sporadic tumor. The authors present a case of CMV-PTC in a 10-year-old girl patient without FAP history, who presented with a left neck mass. The patient underwent total thyroidectomy with central compartment neck dissection. Histopathological diagnosis was compatible with cribriform-morular variant of papillary thyroid carcinoma and Hashimoto's thyroiditis. Immunostaining was positive for thyroglobulin, β-catenin, CD10 and p53. Molecular test showed the absence of BRAF, K-RAS mutations, deletions or duplications of APC (adenomatosis polyposis coli) gene and showed the presence of RET÷PTC (rearranged during transfection÷papillary thyroid carcinoma) rearrangements. At 32 months follow-up, the patient was without signs of recurrence. This particular form of thyroid carcinoma should raise suspicion of a possible familial cancer syndrome, therefore early diagnosis and thoroughly evaluation, which includes colonoscopy and genetic screening are mandatory.