The hobnail variant of @entity3557 ( @entity3557 ) is a rare, aggressive variant in which > 30% of the @entity5 cells have hobnail features. The clinical behavior and pathologic characteristics of these @entity5 are still unclear due to the rarity of the entity. The present study aimed to investigate cytologic, clinical, pathological, and molecular features of the hobnail variant from our data and from the literature. We retrospectively retrieved 10 cases of hobnail variant from 2,904 consecutive @entity3557 @entity1 . Cytologic and histopathologic slides from those 10 @entity1 were reviewed. We performed molecular analysis for @entity817 , @entity7041 , and @entity2215 promoter mutations on paraffin blocks from surgical specimens, and further analyzed the clinicopathologic characteristics of all case reports published in the literature until now. Cytologically, all @entity5 were characterized by single cells with eccentric nuclei and tapering cytoplasm (comet-like cells), and syncytial or micropapillary clusters with apically placed nuclei resulting in a hobnail appearance in both conventional smears and liquid-based cytology. The @entity817 @entity8554 mutation was found in 8 cases (80%) whereas no cases had @entity7041 fusion or @entity2215 promoter mutations. In the literature review of 55 @entity1 including our cases, most @entity1 presented with advanced stage @entity5 , and disease-specific survival rates were 83%, 71%, and 54% at 5, 10, and 20 years after the initial surgery, respectively. Characteristic cytologic features can allow a preoperative diagnosis of the hobnail variant of @entity3557 based on cytology specimens. Further studies should be performed to identify the molecular genetics of the variant.

Cytologic, clinicopathologic, and molecular features of XXXX with prominent hobnail features: 10 case reports and systematic literature review.

@entity3557 :: ('MESH:C536915', 'Disease') :: ['papillary thyroid carcinoma', 'PTC'] @entity1 :: ('9606', 'Species') :: ['patients'] @entity7041 :: ('238', 'Gene') :: ['ALK'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'cancer', 'tumors'] @entity8554 :: ('p|SUB|V|600|E', 'ProteinMutation') :: ['V600E'] @entity817 :: ('673', 'Gene') :: ['BRAF'] @entity2215 :: ('7015', 'Gene') :: ['TERT']
@entity3557 :: (MESH:C536915,Disease) :: ['papillary thyroid carcinoma']
