Molecular grade (FGFR3/MIB-1) and EORTC risk scores are predictive in primary non-muscle-invasive bladder cancer.
BACKGROUND
The European Organization for Research and Treatment of Cancer (EORTC) risk scores are not validated in an independent patient population. Molecular grade (mG) based on fibroblast growth factor receptor 3 (FGFR3) gene mutation status and MIB-1 expression was proposed as an alternative to pathologic grade in bladder cancer (BCa) [1].


OBJECTIVE
To validate the EORTC risk score and to determine its relation to mG in a series with long-term follow-up as well as to determine reproducibility of pathologic grade and mG.


METHODS
In this multicenter study, we included 230 patients with primary non-muscle-invasive BCa (NMIBC).


METHODS
Four uropathologists reviewed the slides. FGFR3 mutation status was examined by two assays. MIB-1 was assessed by immunohistochemistry. The EORTC risk scores for recurrence and progression were determined. Multivariable analyses were used to find prognostic factors.


CONCLUSIONS
Median follow-up was 8.62 yr (interquartile range: 6.6-11.8). FGFR3 mutations were significantly related to favorable disease parameters, whereas altered MIB-1 was frequently seen with pT1, high grade, and high EORTC risk scores. EORTC risk scores were significant in multivariable analyses for recurrence and progression. In multivariable analyses for progression and disease-specific survival, the mG had independent significance. The addition of mG to the multivariable model for progression increased the predictive accuracy from 74.9% to 81.7% (p<0.001; Mantel-Haenszel test). The mG (89%) was more reproducible than the pathologic grade (41-74%).


CONCLUSIONS
We validated the EORTC risk scores for primary NMIBC in a clinical and biomarker setting. Next to EORTC risk score, mG proved highly reproducible and predictive. Our long-term results justify an independent prospective analysis of mG and EORTC risk scores.
van Rhijn
Bas W G
BW
Department of Urology, Erasmus MC, Rotterdam, The Netherlands. basvanrhijn@hotmail.com
Zuiverloon
Tahlita C M
TC
Vis
André N
AN
Radvanyi
François
F
van Leenders
Geert J L H
GJ
Ooms
Bert C M
BC
Kirkels
Wim J
WJ
Lockwood
Gina A
GA
Boevé
Egbert R
ER
Jöbsis
Adriaan C
AC
Zwarthoff
Ellen C
EC
van der Kwast
Theo H
TH
D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D009361:Neoplasm Invasiveness; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000473:pathology*