title: Histologic grading of urothelial papillary neoplasms: impact of combined grading (two-numbered grading system) on reproducibility.
abstract: The clinical management of tumor patients is often strongly influenced by the tumor grade. The presence of heterogeneity is well recognized in a variety of tumors. Overall grade is based on highest grade area identified within a tumor. Urothelial carcinoma often contains different histological grades within the same tumor. This study investigates the impact of a combined grading system on the reproducibility of papillary urothelial neoplasms. A set prepared for an earlier study consisting of ten cases of each category (papillary urothelial neoplasm of low malignant potential (PUNLMP), LGPUC, and HGPUC) was used. Agreement between pairs of pathologists was evaluated using κ statistics for the combined scoring system. Interobserver agreement was fair to substantial as reflected by κ values ranging from 0.24 to 0.74 (mean κ = 0.43). The combined scores of 2 and 3 which included PUNLMP showed the lowest degree of agreement and when this category was excluded from the analysis, interobserver agreement increased significantly (mean κ = 0.65; ranging from 0.43 to 0.92) in terms of combined scores of 4, 5, and 6. PUNLMP has been shown to be the least reproducible component of a combined scoring system even among experienced observers. Exclusion of PUNLMP from grading scheme seems to improve interobserver variability.
authors.affiliation: Department of Pathology, School of Medicine, Dokuz Eylul University, Izmir, Turkey. burcin.tuna@deu.edu.tr
authors.forename: Burçin
authors.initials: B
authors.lastname: Tuna
authors.forename: Kutsal
authors.initials: K
authors.lastname: Yörükoglu
authors.forename: Ender
authors.initials: E
authors.lastname: Düzcan
authors.forename: Sait
authors.initials: S
authors.lastname: Sen
authors.forename: Nalan
authors.initials: N
authors.lastname: Nese
authors.forename: Banu
authors.initials: B
authors.lastname: Sarsık
authors.forename: Aysegul
authors.initials: A
authors.lastname: Akder
authors.forename: Sehnaz
authors.initials: S
authors.lastname: Sayhan
authors.forename: Uğur
authors.initials: U
authors.lastname: Mungan
authors.forename: Ziya
authors.initials: Z
authors.lastname: Kirkali
mesh_terms: D002291:Carcinoma, Papillary / Q000145:classification* / Q000175:diagnosis / Q000473:pathology*; D002965:Classification / Q000379:methods*; D006801:Humans; D015588:Observer Variation; D015203:Reproducibility of Results; D001749:Urinary Bladder Neoplasms / Q000145:classification* / Q000175:diagnosis / Q000473:pathology*; D019459:Urothelium / Q000473:pathology*; D014944:World Health Organization