Effectiveness of two ultrasound-guided transrectal biopsy schemes in the diagnosis of prostate cancer. A randomized study.
OBJECTIVE
To determine whether a 10-core prostate biopsy scheme is superior to the sextant scheme in diagnosing prostate cancer in patients programmed for a first biopsy, with negative rectal digital examination and PSA between 3.5-20 ng/ml.


METHODS
A randomized prospective study was performed comparing two prostate biopsy schemes, with randomization stratification according to prostate volume (< or = 50 ml and > 50 ml). Sample size predetermination yielded a minimum of 304 patients in order to achieve the primary objective. Statistical analysis was carried out on an intent-to-treat basis, using the chi-squared test and uni- and multivariate analysis via logistic regression.


RESULTS
Cancer was detected in 27.3% of the cases. A significant association was observed between cancer diagnosis and age (p=0.03), prostate volume (p=0.0001) and ultrasound nodule identification (p=0.0001). No correlation was observed with the total number of cores in the series (p=0.37) or with prostate volume < or = 50 ml (p=0.87) or > 50 ml (p=0.09). In the multivariate analysis, age > 70 years (p=0.005), prostate volume < or = 50 ml (p=0.001), and ultrasound nodule identification (p=0.003) were identified as independent variables associated to cancer diagnosis.


CONCLUSIONS
No statistically significant differences were found between the two prostate biopsy schemes. In glands over 50 ml in size, the sextant scheme may prove to be insufficient.
Herranz Amo
Felipe
F
Urology Department, Hospital General Universitario Gregorio Marañon, Madrid, Spain. felipeherranz@telefonica.net
Jara Rascón
José
J
Cancho Gil
María José
MJ
Tabares Jiménez
Juan
J
Molina Escudero
Roberto
R
Hernández Fernández
Carlos
C
D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D014463:Ultrasonography