P53 protein expression in transitional cell carcinoma of the bladder - experience of the University of Malaya Medical Centre.
OBJECTIVE
To study the incidence of p53 oncoprotein overexpression and its relationship to tumour grade, stage and clinical prognosis in a cohort of local Malaysian patients.


METHODS
All cases of transitional cell carcinoma (TCC) of the bladder diagnosed and treated at the University of Malaya Medical Centre from January 1995 to December 2000 were retrieved from the hospital records. Sections from paraffin-embedded tissues were retrieved and stained for p53 oncoprotein using immunohistochemistry techniques. P53 oncoprotein results were analyzed in relation to tumour grade, stage and clinical prognosis. Fisher's exact test was used to evaluate the relationship between categorical variables and the Kaplan-Meier procedure was used to assess survival outcomes. The Cox regression model was used for multivariate analysis.


RESULTS
A total of 64 cases were studied. The mean follow-up period was 23.7 months. The number of p53 positive cases was significantly higher in high-grade (G3) (p = 0.006) and muscle-invasive tumours ( summation operator T2, p = 0.035). The status of p53 expression had no significant association with recurrence-free (p = 0.594) or overall survival (p = 0.955). In multivariate analysis, a multiplicity of tumours at presentation (p = 0.004) and a history of cigarette smoking (p = 0.016) were independent predictors of recurrence. Tumour stage (p = 0.024) was the single independent predictor for poor overall survival.


CONCLUSIONS
Overexpression of p53 is associated with TCC of higher grade and tumour stage. It had no significant impact on prognosis in this cohort of TCC cases.
Ong
Teng A
TA
Division of Urology, Department of Surgery, University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
Peh
Suat C
SC
Goh
Kenny S K
KS
Naicker
Mala S
MS
Khan
Afzal F
AF
Chua
Beng C
BC
Razack
Azad
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002295:Carcinoma, Transitional Cell / Q000378:metabolism*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D001748:Urinary Bladder Neck Obstruction / Q000378:metabolism*
D016159:Tumor Suppressor Protein p53