title: The micropapillary/hobnail variant of papillary thyroid carcinoma: A review of series described in the literature compared to a series from one southern Italy pathology institution.
abstract: Papillary thyroid carcinoma (PTC) has a good prognosis with a 10-yr survival greater than 90%. Recently, a micro-papillary pattern with hobnail appearance (MPHC) in PTC has been indicated as associated with poor prognosis, but this suggestion is based only on a few cases from geographical areas different from ours. Two-hundred ninety-nine consecutive PTC cases were collected between the years of 1992 and 2014 at our institution. The corresponding histologic sections (at least 6 for each case) were stained with hematoxylin and eosin and reviewed independently by two pathologists to reach a consensus on the identification and quantification of the MPHC. As done in other cohorts, parallel serial sections were stained with antisera for thyroglobulin, epithelial membrane antigen, thyroid-transcription-factor-1 and Ki 67. BRAF gene mutation at codon 600 and RET/PTC1 gene rearrangements were searched. A comparative statistical analysis was done between the present series and previously published series. Of the 295 PTC, 124 (42.5%) were follicular, 104 (35%) classic, 34 (11.5%) sclerosing, 15 (5%) tall cells, 10 (3.4%) Warthin-like, and 8 (2.7%) MPHC. Four MHPC cases (50%) harbored the BRAF V600E variant, while one was positive for RET/PTC1 rearrangement. Our rate of MPHC-PTC (2.7%) is 2X to 8X greater than those reported previously for cohorts from North America + North Italy, Korea and Mexico. MPHC prognosis appears to be better compared to other cohorts, probably due to not only to the lower rate of the vascular invasion, but also to the smaller size of the MPHC-PTC nodule.
authors.affiliation: Department of Human Pathology "Gaetano Barresi" - Section of Pathological Anatomy, A.O.U. Polyclinic G.Martino, 98125, Messina, Italy. aieni@unime.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Ieni
authors.affiliation: Department of Human Pathology "Gaetano Barresi" - Section of Pathological Anatomy, A.O.U. Polyclinic G.Martino, 98125, Messina, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Barresi
authors.affiliation: Department of Human Pathology "Gaetano Barresi" - Section of Pathological Anatomy, A.O.U. Polyclinic G.Martino, 98125, Messina, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Cardia
authors.affiliation: Department of Human Pathology "Gaetano Barresi" - Section of Pathological Anatomy, A.O.U. Polyclinic G.Martino, 98125, Messina, Italy.
authors.forename: Luana
authors.initials: L
authors.lastname: Licata
authors.affiliation: Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.|Master Program on Childhood, Adolescent and Women's Endocrine Health, University of Messina, Messina, Italy.|Interdepartmental Program of Molecular & Clinical Endocrinology and Women's Endocrine Health, University Hospital, A.O.U. Policlinico G. Martino, Messina, Italy.
authors.forename: Flavia
authors.initials: F
authors.lastname: Di Bari
authors.affiliation: Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.|Master Program on Childhood, Adolescent and Women's Endocrine Health, University of Messina, Messina, Italy.|Interdepartmental Program of Molecular & Clinical Endocrinology and Women's Endocrine Health, University Hospital, A.O.U. Policlinico G. Martino, Messina, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Benvenga
authors.affiliation: Department of Human Pathology "Gaetano Barresi" - Section of Pathological Anatomy, A.O.U. Polyclinic G.Martino, 98125, Messina, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Tuccari
mesh_terms: D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D002291:Carcinoma, Papillary / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D011379:Prognosis; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000378:metabolism / Q000473:pathology*
keywords: Hobnail; Micropapillary; Papillary carcinoma; Prognosis; Thyroid