Intraobserver and interobserver variability of Fuhrman and modified Fuhrman grading systems for conventional renal cell carcinoma.
The Fuhrman nuclear grade is the most widely used grading system for renal cell carcinoma. The aim of this study was to evaluate the intraobserver and interobserver variability of the Fuhrman and modified Fuhrman grading systems for conventional renal cell carcinoma. In this study, five pathologists independently classified 110 cases of conventional renal cell carcinoma according to the Fuhrman and modified (three- and two-tiered) Fuhrman grading systems. The intraobserver and interobserver variability of these systems were assessed using kappa statistics. The associations between the Fuhrman and modified Fuhrman grades, pathologic stage and tumor size were determined by correlation analysis. The intraobserver and interobserver combined mean kappa values for four-tiered Fuhrman grading were 0.48 and 0.41, respectively. The highest agreement was detected in two-tiered modification (including grades 1 + 2 and 3 + 4); the intraobserver and interobserver combined mean kappa values were 0.67 and 0.62, respectively. Correlations between pathologic stage and tumor size with two-tiered modification (including grades 1 + 2 and 3 + 4) were greater than those in three- and four-tiered Fuhrman grading. Collapsing the Fuhrman grading into a two-tiered scheme improved the intraobserver and interobserver reproducibility.
Department of Pathology, School of Medicine, Zonguldak Karaelmas University, Kozlu, Zonguldak, Turkey. sibel_bektas@yahoo.com
Sibel
S
Bektas
Burak
B
Bahadir
Nilufer Onak
NO
Kandemir
Figen
F
Barut
Aylin Ege
AE
Gul
Sukru Oguz
SO
Ozdamar
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000473:pathology*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015588:Observer Variation; D055815:Young Adult