Cribriform - morular thyroid carcinoma: a rare entity.

We present a case report of a 51-year-old patient who underwent totalization of thyroidectomy - resection of the right thyroid lobe for growth progression of the largest nodule from which a fine needle aspiration biopsy (FNAB) was performed and was cytologically suspected of malignancy. Nodule was a graywhite colored tumor with a solid structure, histologically with an unusual morphology and immunoprofile, called cribriform morular thyroid carcinoma (CMTC). Usually, the tumor behaves indolently with a good prognosis. CMTC can be familial or sporadic, predominantly as a solitary or a multifocal lesion, often associated with autosomal dominant adenomatous polyposis syndrome (FAP), so it is necessary to point this out in the report. The syndrome of familial adenomatous polyposis was ruled out, the APC gene mutation was somatic.