title: Rhabdoid variant of urothelial carcinoma of the urinary bladder: a case report with emphasis on immunohistochemical analysis regarding the formation of rhabdoid morphology.
abstract: Various histological variants of urothelial carcinoma (UC) have been described. They are associated with different clinical outcomes and/or therapeutic approaches; in addition, recognition of these histological variants is also important in preventing diagnostic misinterpretations. Histological variants based on cytoplasmic features, such as plasmacytoid, rhabdoid, clear-cell, and lipoid-rich variants, have been described in invasive UC. Herein, we report an exceedingly rare case of a rhabdoid variant of UC arising in the urinary bladder of a 61-year-old man. Including UC, the presence of rhabdoid cells has been described in various types of malignant tumors. These tumors are regarded as more aggressive neoplasms than those without rhabdoid cells. It has been previously found that non-degraded aggregation of intermediate filaments and membrane proteins conjugated with ubiquitin and p62 is a noticeable finding in the formation of rhabdoid morphology. We have validated the existence of this mechanism in a rhabdoid variant of UC by extensive immunohistochemical analysis.
authors.affiliation: Department of Pathology, Shizuoka Saiseikai General Hospital Shizuoka, Japan ; Department of Pathology, Fujieda Municipal General Hospital Shizuoka, Japan ; Department of Pathology, Graduate School of Medicine, The University of Tokyo Tokyo, Japan.
authors.forename: Shogo
authors.initials: S
authors.lastname: Tajima
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D002295:Carcinoma, Transitional Cell / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D001749:Urinary Bladder Neoplasms / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor
keywords: Immunohistochemistry; p62; rhabdoid variant; ubiquitin; urinary bladder; urothelial carcinoma