title: Cribriform-morular variant of papillary thyroid carcinoma: molecular characterization of a case with neuroendocrine differentiation and aggressive behavior.
abstract: We describe an especially aggressive case of cribriform-morular variant (C-MV) of papillary thyroid carcinoma (PTC) in a 42-year-old man with familial adenomatous polyposis who died with lung and brain metastases 17 months after thyroidectomy. The angioinvasive neoplasm combined a mixture of trabecular, solid, cribriform, and follicular patterns of growth with CD10+ morules. Follicles were devoid of colloid, and the nuclear features typical of PTC were present in some areas and missing in others. Tumor cells were positive for thyroid transcription factor-1 and, in 40% of the tumoral mass, also were positive for chromogranin and synaptophysin and were negative for thyroglobulin and calcitonin. Strong nuclear staining for beta-catenin was found in all tumor cells, as was positivity for p53 and cyclin D1. In addition to the germline heterozygous APC Ex 2-3 duplication mutation, a somatic homozygous silent p. Thr1493Thr gene variant was found in the neoplastic cells along with RET/PTC rearrangement. This tumor represents the first case of C-MV of PTC showing neuroendocrine differentiation.
authors.affiliation: Department of Pathology, Clinical University Hospital, Galician Health Service, University of Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Cameselle-Teijeiro
authors.forename: Lia P
authors.initials: LP
authors.lastname: Menasce
authors.forename: Beng K
authors.initials: BK
authors.lastname: Yap
authors.forename: Rovel J
authors.initials: RJ
authors.lastname: Colaco
authors.forename: Patricia
authors.initials: P
authors.lastname: Castro
authors.forename: Ricardo
authors.initials: R
authors.lastname: Celestino
authors.forename: Clara
authors.initials: C
authors.lastname: Ruíz-Ponte
authors.forename: Paula
authors.initials: P
authors.lastname: Soares
authors.forename: Manuel
authors.initials: M
authors.lastname: Sobrinho-Simões
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D011125:Adenomatous Polyposis Coli / Q000473:pathology; D000328:Adult; D001932:Brain Neoplasms / Q000556:secondary; D002291:Carcinoma, Papillary / Q000473:pathology*; D017809:Fatal Outcome; D006801:Humans; D008175:Lung Neoplasms / Q000556:secondary; D008297:Male; D013964:Thyroid Neoplasms / Q000473:pathology*