Prognostic role of Fuhrman grade and vascular endothelial growth factor in pT1a clear cell carcinoma in partial nephrectomy specimens.
OBJECTIVE
Conventional renal cell carcinoma (RCC) is characterized by rich neovascularization and shows a fine vascular network around tumor cells. Nephron sparing surgery has been established as a method of choice or necessity for localized tumors. We investigated the importance of microvessel density (MVD), vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (Flk-1) immunohistochemical expression in a large series of small conventional clear cell renal carcinomas treated with partial nephrectomy and assessed the prognostic value of their expression in terms of patients survival at long-term followup.


METHODS
A total of 48 patients with a mean age +/- SD of 58.2 +/- 9.5 years who had conventional single RCC were considered. Median tumor diameter was 2.92 +/- 0.82 cm (range 1.3 to 5). Disease was grades 1 to 4 in 15, 29, 2 and 2 patients, respectively. Median followup was 92.9 months (range 17 to 186).


RESULTS
Four patients (3.9%) had died of metastatic renal cancer at a median followup of 23.5 months, of whom 1 had a grade 2, 1 had a grade 3 and 2 had grade 4 RCC. Patients with MVD expression higher than the median (44.4 vessels per mm) did not show a significant difference in survival compared to patients with MVD expression lower than the median. Patients with VEGF expression higher than 25% in the histological specimen showed worse survival than patients with VEGF expression lower than 25%. Different Flk-1 expression did not determine a significant difference in survival. On univariate analysis of patient survival in relation to the different considered factors Fuhrman grading was the most important factor for survival.


CONCLUSIONS
Our study shows that recurrence and death are possible even in patients with small renal tumors. MVD, VEGF and Flk-1 expression do not depend on tumor size in pT1a RCC. Therefore, to date Fuhrman grading appears to be the only factor predictive of survival even in small RCC. Thus, Fuhrman grading is predictive of mortality. While VEGF is not predictive of survival as a single parameter, based on its percent of expression (lower or higher than 25%) it can determine 2 groups that are different from the prognostic point of view.
Minardi
D
D
Institute of Urology, Polytechnic University of the Marche Region Medical School, Ancona, Italy.
Lucarini
G
G
Mazzucchelli
R
R
Milanese
G
G
Natali
D
D
Galosi
A B
AB
Montironi
R
R
Biagini
G
G
Muzzonigro
G
G
D018262:Adenocarcinoma, Clear Cell / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D000328:Adult; D000368:Aged; D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy; D011379:Prognosis; D016019:Survival Analysis; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism
D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2