INTRODUCTION AND OBJECTIVES: Epidermal Growth Factor
Receptor (EGFR) overexpression has been recognized as a marker
of biological aggressiveness in several malignant neoplasms. EGFR
studies on non-muscle invasive bladder cancer (NMIBC) are lacking.
Urothelial EGFR status after TUR could provide useful information
about the risk of recurrence and progression. The aim of our study was
to investigate the feasibility of EGFR evaluation in bladder washings of
patients affected by NMIBC correlating its expression to European
Association of Urology (EAU) risk classes.
METHODS: A prospective double-blinded study included patients
undergoing adjuvant intravesical therapy for NMIBC and age-matched
healthy controls. Acellular pelletwas obtained and stored at -80C. Isolation
of cellular RNA was performed using a miRNeasy Mini Kit (Qiagen) and
DNA derived from reverse transcription was used to perform gene expression
analysis by a Real Time PCR according to ??Ct method.
RESULTS: Fifty-eight patients and 21 controls entered the
study. One hundred fifty-three samples were collected. A useful pellet
was obtained in 50 patients (86.2%) and 18 controls (85.7%). The mean
EGFR expression in 50 NMIBC was 1.94 folds (range: 0.10-8.00).
Compared with healthy controls (EGFR¼1), 40 patients (80%) were
positive for EGFR. Particularly, in 18 patients (36%) EGFR was overexpressed
(EGFR>1.94) with a mean value of 3.61 folds (range: 2.00-
8.00). According to EAU risk groups, EGFR expression was evaluated
in low, intermediate and high risk patients respectively. In 20 high risk
NMIBC the mean EGFR expression resulted 2.45 folds and 10 of them
(50%) presented significant up-regulation with a mean value of 4.10
folds (range: 2.30-8.00). CONCLUSIONS: Our preliminary study demonstrates the
feasibility of EGFR determination in bladder washings of patients
affected by NMIBC after TUR, during adjuvant treatment and subsequent
follow-up. A useful pellet was available in more than 85% of
patients, with evidence of up-regulation in 36% of them. Within the high
risk category, a significant overexpression of EGFR, mean value of 4.16
folds, was detected. EGFR overexpression might identify a subgroup of
high risk tumors inclined to progression despite of intravesical therapy
and could represent an additional prognostic factor to select candidates
for early radical cystectomy
