TY - JOUR
T1 - Grading of clear cell renal cell carcinoma should be based on nucleolar prominence
AU - Delahunt, Brett
AU - Sika-Paotonu, Dianne
AU - Bethwaite, Peter B.
AU - William Jordan, Thomas
AU - Magi-Galluzzi, Cristina
AU - Zhou, Ming
AU - Samaratunga, Hemamali
AU - Srigley, John R.
PY - 2011/8
Y1 - 2011/8
N2 - Fuhrman grading of renal cell carcinoma focuses on features of nuclear size, nuclear shape, and nucleolar prominence. Despite the reported widespread usage of Fuhrman grading in clinical studies, there is debate as to the prognostic significance and reproducibility of its criteria. It has been noted that many pathologists rely on assessment of nucleolar prominence alone when grading renal cell carcinoma; however, the validity of this remains unconfirmed. This study was undertaken to determine the relationship of the 3 morphologic components of the Fuhrman grading system with one another and to determine which, if any of these, can be correlated with outcome for clear cell renal cell carcinoma. One hundred twenty-one organ-confined clear cell renal cell carcinomas were examined in this study. Parameters of nuclear size (area, major axis, perimeter) and nuclear shape (shape factor, nuclear compactness) were assessed by image analysis, whereas nucleolar prominence was assigned (grades 1 to 3) using the criteria of Fuhrman. On the basis of the predominant grade present, there were 17 nucleolar grade 1, 90 nucleolar grade 2, and 14 nucleolar grade 3 tumors. When the high-power field in each tumor with the worst nucleolar grade was assessed, there was 1 nucleolar grade 1, 68 nucleolar grade 2, and 52 nucleolar grade 3 tumors. Predominant and worst nucleolar grade correlated with all measures of nuclear size, but not nuclear shape. Worst nucleolar grade and all parameters of nuclear size were significantly associated with outcome. On multivariate analysis, worst nucleolar grade retained a significant association with survival when modeled with nuclear area. Neither worst nucleolar grade nor major nuclear axis/nuclear perimeter was significantly associated with survival when modeled together. In this study, we have shown that worst nucleolar grade and nuclear size are of prognostic significance for clear cell renal cell carcinoma. We have further shown the association of worst nucleolar grade with outcome to be independent of nuclear area, whereas it is a dependent variable when tested against other parameters of nuclear size. These findings indicate that worst nucleolar grading alone is a valid grading parameter for clear cell renal cell carcinoma.
AB - Fuhrman grading of renal cell carcinoma focuses on features of nuclear size, nuclear shape, and nucleolar prominence. Despite the reported widespread usage of Fuhrman grading in clinical studies, there is debate as to the prognostic significance and reproducibility of its criteria. It has been noted that many pathologists rely on assessment of nucleolar prominence alone when grading renal cell carcinoma; however, the validity of this remains unconfirmed. This study was undertaken to determine the relationship of the 3 morphologic components of the Fuhrman grading system with one another and to determine which, if any of these, can be correlated with outcome for clear cell renal cell carcinoma. One hundred twenty-one organ-confined clear cell renal cell carcinomas were examined in this study. Parameters of nuclear size (area, major axis, perimeter) and nuclear shape (shape factor, nuclear compactness) were assessed by image analysis, whereas nucleolar prominence was assigned (grades 1 to 3) using the criteria of Fuhrman. On the basis of the predominant grade present, there were 17 nucleolar grade 1, 90 nucleolar grade 2, and 14 nucleolar grade 3 tumors. When the high-power field in each tumor with the worst nucleolar grade was assessed, there was 1 nucleolar grade 1, 68 nucleolar grade 2, and 52 nucleolar grade 3 tumors. Predominant and worst nucleolar grade correlated with all measures of nuclear size, but not nuclear shape. Worst nucleolar grade and all parameters of nuclear size were significantly associated with outcome. On multivariate analysis, worst nucleolar grade retained a significant association with survival when modeled with nuclear area. Neither worst nucleolar grade nor major nuclear axis/nuclear perimeter was significantly associated with survival when modeled together. In this study, we have shown that worst nucleolar grade and nuclear size are of prognostic significance for clear cell renal cell carcinoma. We have further shown the association of worst nucleolar grade with outcome to be independent of nuclear area, whereas it is a dependent variable when tested against other parameters of nuclear size. These findings indicate that worst nucleolar grading alone is a valid grading parameter for clear cell renal cell carcinoma.
KW - Fuhrman grade
KW - clear cell renal cell carcinoma
KW - image analysis
KW - nuclear shape
KW - nuclear size
KW - nucleolar grade
KW - prognosis
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UR - http://www.scopus.com/inward/citedby.url?scp=79961023141&partnerID=8YFLogxK
U2 - 10.1097/PAS.0b013e318220697f
DO - 10.1097/PAS.0b013e318220697f
M3 - Article
C2 - 21716085
AN - SCOPUS:79961023141
SN - 0147-5185
VL - 35
SP - 1134
EP - 1139
JO - American Journal of Surgical Pathology
JF - American Journal of Surgical Pathology
IS - 8
ER -