IMP3 predicts aggressive superficial urothelial carcinoma of the bladder.
OBJECTIVE
In this study, we investigated whether an oncofetal protein, IMP3, can serve as a new biomarker to predict progression and metastasis of early-stage urothelial carcinoma of the bladder.


METHODS
The expression of IMP3 in 242 patients with primary superficial bladder urothelial carcinoma and metastatic urothelial carcinoma was evaluated by immunohistochemistry. Patients with primary superficial urothelial carcinoma of the bladder were further investigated by use of survival analysis.


RESULTS
Twenty percent (42 of 214) of primary superficial urothelial carcinomas and 93% (26 of 28) of metastatic urothelial carcinomas expressed IMP3. Kaplan-Meier plots and log-rank tests showed that patients with IMP3-positive tumors had a much lower progression-free survival (P = 0.0002) and disease-free survival rate (P = 0.0067) than did those with IMP3-negative tumors. The 5-year progression-free and disease-free survival rates were 91% and 94% in IMP3-negative patients versus 64% and 76% in IMP3-positive patients, respectively. Sixty percent of IMP3-positive patients with superficial invasive urothelial carcinoma at initial diagnosis went on to develop metastases, whereas no metastasis was found in IMP3-negative patients (P = 0.0017). In the multivariable Cox analysis, patients with IMP3 expression in their superficial urothelial carcinomas subsequently developed invasive tumors or metastasis at a rate that was about five times greater than cases without expression of IMP3 adjusting for other well-known clinical variables (tumor stage and grade, etc.).


CONCLUSIONS
Our findings indicate that IMP3 is an independent prognostic marker that can identify a group of patients with a high potential to develop progression and who might benefit from early aggressive therapy.
Sitnikova
Lioudmila
L
Department of Urology, University of Massachusetts Medical Center, Worcester, Massachusetts 01605, USA.
Mendese
Gary
G
Liu
Qin
Q
Woda
Bruce A
BA
Lu
Di
D
Dresser
Karen
K
Mohanty
Sambit
S
Rock
Kenneth L
KL
Jiang
Zhong
Z
D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D002291:Carcinoma, Papillary / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000378:metabolism* / Q000502:physiology; D011379:Prognosis; D016601:RNA-Binding Proteins / Q000378:metabolism* / Q000502:physiology; D016019:Survival Analysis; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D019459:Urothelium / Q000378:metabolism / Q000473:pathology
D014408:Biomarkers, Tumor; C498780:IGF2BP3 protein, human; D009363:Neoplasm Proteins; D016601:RNA-Binding Proteins